ﺑﺎﺯﮔﺸﺖ ﺑﻪ ﺻﻔﺤﻪ ﻗﺒﻠﯽ
خرید پکیج
تعداد آیتم قابل مشاهده باقیمانده : 3 مورد
نسخه الکترونیک
medimedia.ir

Immunizations for health care providers

Immunizations for health care providers
Literature review current through: May 2024.
This topic last updated: Dec 13, 2022.

INTRODUCTION — Health care providers are at risk for exposure to and acquisition of vaccine preventable diseases. This risk can be minimized by:

Strict adherence to handwashing [1]

Rapid institution of appropriate isolation for patients with known or suspected communicable diseases [2]

Maintaining up to date immunizations in health care providers

Additional precautions should be taken by personnel working in the microbiology or pathology laboratory, such as no eating or drinking in areas where specimens are processed and use of protective equipment when culturing pathogens such as Mycobacterium tuberculosis [3-5].

Health care providers are also susceptible to nosocomial exposure to tuberculosis from hospitalized patients. This risk is even greater in certain regions of the world where admission rates for TB are extremely high [6]. Issues related to TB screening in health care workers are discussed separately. (See "Tuberculosis infection (latent tuberculosis) in adults: Approach to diagnosis (screening)", section on 'Health care workers in some settings'.)

The use of immunizations to prevent infection in health care providers will be reviewed here. The value of handwashing and isolation guidelines is discussed separately. (See "Infection prevention: Precautions for preventing transmission of infection".)

WHICH HEALTH CARE PROVIDERS SHOULD BE IMMUNIZED AGAINST VACCINE-PREVENTABLE DISEASES?

Immunization policies — The Centers for Disease Control and Prevention (CDC) recommends that immunization programs be provided for all health care providers in hospitals, health departments, private clinician offices, nursing homes, schools and laboratories, and emergency medical personnel (figure 1 and figure 2) [7]. All medical facilities or health departments that provide direct patient care are encouraged to formulate and implement a comprehensive immunization policy for all health care providers. This policy should describe exactly what the risk of exposure to vaccine preventable diseases is, according to job description.

Recommendations for immunization should be based upon the risk of exposure. All new employees should receive a prompt review of their immunization status prior to starting to care for patients; in addition, all employees should have an annual review to ensure that immunizations remain up to date.

Medical documentation — Immunization is recommended when prior vaccine administration cannot be documented, unless the health care provider has a contraindication to vaccine administration. Serologic screening for immunity is generally not considered cost-effective. All vaccine-related information should be documented in the health care provider's medical record [8].

Failure to immunize — Despite these recommendations, large numbers of health care providers lack immunity to hepatitis B, influenza, measles, mumps, and rubella [9-15]. There are two major reasons for failure of the recommendations.

Some health care providers refuse to be immunized. In one study of medical school clinical employees, for example, only 77 percent completed the hepatitis B vaccine series [9]. Reasons why health care providers refuse vaccines for these diseases include: desire to avoid medications, concern about side effects, belief that the vaccine is ineffective (influenza), and belief that the risk of acquiring disease is low (hepatitis B) [14,16]. Factors that predict acceptance of the influenza vaccine included older age, higher economic status, and prior work absenteeism [17].

A second reason for failure to immunize health care providers is inadequate policies and inconsistent enforcement of policies. In a community-wide outbreak of measles that occurred in 1996, only 47 percent of medical facilities had an immunization policy and only 21 percent of facilities met Advisory Committee on Immunization Practices (ACIP) recommendations and enforced their policy [15]. There has also been wide variability in immunization policies for health care providers. In a national survey of children's hospitals, more than 90 percent of the institutions surveyed reported cases of each of the following diseases in their institution in the last five years: measles, tuberculosis, hepatitis B, varicella, and influenza [18]. Education and interventions such as the use of mobile carts that facilitate access to immunization increases immunization rates, but levels remain sub-optimal [19].

WHICH VACCINES SHOULD BE PROVIDED TO HEALTH CARE PROVIDERS? — General recommendations regarding immunization of immunocompetent health care providers have been published by the United States Centers for Disease Control and Prevention (CDC) [7,20], the Association for Professionals in Infection and Epidemiology, Inc (APIC) [21], the American College of Physicians [22], and infectious diseases experts [23-27].

The general approach to immunization is as follows:

All health care providers should be up to date with recommended vaccines and boosters for COVID-19, unless there is a contraindication to vaccination. (See 'COVID-19 vaccine' below.)

All health care providers with potential exposure to blood or body fluids should be immune to hepatitis B virus. (See 'Hepatitis B vaccine' below.)

All health care providers should be offered annual immunization with influenza vaccine. (See 'Influenza vaccine' below.)

All health care providers should be immune to measles, mumps, rubella, and varicella. (See 'Measles, mumps, and rubella vaccine' below.)

All health care workers should receive a one-time dose of Tdap as soon as possible, unless they are certain that they have received Tdap. (See 'Pertussis vaccine' below.)

All health care providers should either be offered immunizations that are routinely recommended for adults, such as tetanus, diphtheria, and pneumococcal vaccine, or be referred to their primary care provider. (See 'Vaccines for other preventable diseases' below.)

Selected health care providers and laboratory personnel should be offered certain vaccines depending upon their specific risk. These may include vaccines to prevent Ebola virus disease, smallpox, mpox, polio, meningococcal disease, rabies, plague, typhoid, and hepatitis A.

Special considerations for immunocompromised health care providers are discussed separately. (See "Immunizations in adults with cancer" and "Immunizations in persons with HIV".)

COVID-19 vaccine — Vaccination with one of the available coronavirus disease 2019 (COVID-19) vaccines is indicated for all health care workers unless there is a contraindication (eg, allergic reactions to the vaccines or their components). Observational data from several health systems support the efficacy of vaccination in reducing SARS-CoV-2 infections in health care workers. A detailed discussion of vaccination to prevent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is presented elsewhere. (See "COVID-19: Vaccines".)

Hepatitis B vaccine — In 2004, there were an estimated 304 hepatitis B virus infections that occurred among health care providers in the United States, a substantial decrease from the estimated 10,000 annual infections that occurred in the early 1980s [7]. This decrease is due, in large part, to vaccination of health care providers [28].

HBV is more transmissible than hepatitis C virus (HCV) or human immunodeficiency virus (HIV) (table 1). The risk of developing HBV infection is greatest after a needlestick injury. However, infection with HBV has also occurred in health care providers who cannot recall any percutaneous exposure. In this setting, infection has been attributed to breaks in the skin or inoculation through mucous membranes [29-31].

There are a variety of sources of HBV other than blood-containing specimens in the health care environment. These include: contaminated medical instruments [32-37], environmental surfaces [38], and contaminated file cards among laboratory technicians [39]. In dialysis units, transmission of HBV has been associated with the use of common-dose medications and shared equipment [40,41].

A more detailed discussion of transmission of HBV transmission in health care providers is presented elsewhere. (See "Prevention of hepatitis B virus and hepatitis C virus infection among health care providers", section on 'Epidemiology of bloodborne exposures'.)

Recommendations — The Occupational Safety and Health Act of 1991 mandates that hepatitis B vaccine be made available at the employer's expense to all health care providers who are occupationally exposed to blood or other infectious materials or sharps [42]. This recommendation is supported by the CDC [43,44] and the Advisory Committee on Immunization Practices (ACIP) [7]. Vaccination is both safe and effective with seroprotection being achieved in 92 percent of health care providers aged <40 years and 84 percent aged ≥ 40 years [7,43,45-47]. In a study of 159 health care providers who were vaccinated between the ages of 18 and 60 years, approximately 75 percent of individuals had protective hepatitis B surface antibody (anti-HBs) levels 10 to 31 years after they received their initial vaccine series [48].

Assessing immunity

Individuals at risk for prior HBV — For most health care providers, serologic testing prior to immunization is not recommended. However, individuals who are at high risk of having a history of HBV infection should be tested for anti-HBs, hepatitis B core antibody (anti-HBc), and hepatitis B surface antigen (HBsAg), even if they have been previously vaccinated [43]. This includes individuals who:

Are born in geographic regions where the HBsAg prevalence is ≥2 percent (see "Epidemiology, transmission, and prevention of hepatitis B virus infection", section on 'Epidemiology of chronic HBV')

Are born in a region where the HBsAg prevalence is <2 percent, but were not vaccinated as an infant and had parents that were born in a region where the HBsAg prevalence is ≥8 percent (see "Epidemiology, transmission, and prevention of hepatitis B virus infection", section on 'Epidemiology of chronic HBV')

Have behavioral exposures (eg, men who have sex with men, injection drug users) (see "Epidemiology, transmission, and prevention of hepatitis B virus infection", section on 'Transmission of HBV')

Are HIV or HCV positive

Are receiving hemodialysis

Individuals previously vaccinated — Many health care institutions require documentation of anti-HBs >10 milli-international units/mL in those who were previously vaccinated.

Booster doses of vaccine are not recommended for immunocompetent health care providers who have a documented response (ie, anti-HBs >10 milli-international units/mL) to the initial vaccine series (figure 3). Repeat testing is not needed in previous responders, since such individuals remain protected against clinical hepatitis and chronic infection, even when their anti-HBs levels become low or undetectable [7,43,49].

For those with an anti-HBs <10 milli-international units/mL after receiving an initial vaccine series, a booster dose of vaccine should be given to assess immunity (figure 3). Health care providers with a response ≥10 milli-international units/mL one to two months following a challenge dose are considered protected and do not need to be retested in the future [43]. The approach to individuals with an anti-HBs <10 milli-international units/mL is summarized in the figure (figure 3) and discussed in greater detail below. (See 'Follow-up testing after immunization' below.)

Vaccines and dosing schedules — There are three different vaccine preparations available:

Recombinant hepatitis B vaccines (conventional)

Recombivax HB (10 mcg HBsAg/mL)

Engerix-B (20 mcg HBsAg/mL)

Recombinant hepatitis B vaccine (CpG-adjuvanted)

Heplisav-B (20 mcg HBsAg/0.5 mL)

For most patients, the conventional recombinant hepatitis B vaccines (Engerix-B, Recombivax HB) are used, since there is extensive experience with these vaccines and they are safe and immunogenic in most healthy adults. The dosing regimens are summarized in the table (table 2).

The recombinant hepatitis B vaccine that uses a novel immunostimulatory adjuvant (HepB-CpG) was approved for use in the United States in November of 2017 [50]; the optimal use of this vaccine is still to be determined given some outstanding safety concerns. However, this could be considered for health care providers who do not respond to the standard doses of vaccine or who have failed a second single- or double-dose revaccination attempt. In this setting, the potential risks and benefits should be discussed and the decision to vaccinate with HepB-CpG should be made on a case-by-case basis. This vaccine is discussed in detail in a separate topic review. (See "Hepatitis B virus immunization in adults".)

Follow-up testing after immunization — Health care providers should be tested for hepatitis B surface antibody (anti-HBs) one to two months after receiving their final dose of vaccine. Unfortunately, 5 to 21 percent of health care providers do not develop a protective level of anti-HBs after three doses of vaccine [51,52]. Lower rates of seroconversion are associated with increasing age, greater immunocompromise, current smoking, and higher body mass index [51-54].

Anti-HBs should be measured using a quantitative test, and further management depends upon the antibody level [43].

If the anti-HBs level is ≥10 milli-international units/mL, the individual is considered a vaccine responder and is felt to be protected against HBV infection.

If the anti-HBs titer is <10 milli-international units/mL, the individual should receive a single additional dose of vaccine and have anti-HBs titers repeated in one to two months. An adequate antibody response is seen in 15 to 25 percent after one additional dose of vaccine [55].

If, after this additional dose, the anti-HBs titer is still <10 milli-international units/mL, two additional doses should be given, followed by repeat post-vaccination serologic testing at one to two months. An adequate antibody response is seen in 50 percent after three additional doses [55].

If the anti-HBs is still <10 milli-international units/mL, the health care provider is considered a vaccine nonresponder and should receive hepatitis B immune globulin (HBIG) if post-exposure prophylaxis is required. (See "Prevention of hepatitis B virus and hepatitis C virus infection among health care providers", section on 'Post-exposure management'.)

Nonresponders should be tested for anti-HBc and HBsAg to determine their HBV status.

Influenza vaccine — Influenza virus is primarily spread from person to person by large-particle droplet transmission (eg, through coughing or sneezing) [56]. Transmission by fomites or contaminated hands is another potential way the virus can be nosocomially acquired. Patients with influenza have led to nosocomial transmission of disease [57,58], and infected staff have transmitted the virus to patients and other staff [59].

Acquisition of influenza in medical staff results in absenteeism and disruption of health care [60,61]. In addition, nosocomial outbreaks have been responsible for significant morbidity and mortality in nursing homes and other long-term facilities [62-68]. These problems can be reduced by vaccination [69,70]. This was illustrated in a study in which patients in facilities where influenza immunization rates of staff were greater than 60 percent had less influenza-related morbidity and mortality than patients in facilities where less than 60 percent of the staff were vaccinated [69].

During the COVID-19 pandemic there has been an increased emphasis on influenza immunization, including immunization of health care workers, because of the anticipated continued circulation of SARS-CoV-2. Symptoms of influenza cannot be distinguished from SARS-CoV-2 without specific testing for both viruses. Influenza immunization should reduce influenza-like symptoms in health care workers, as well as the risk of simultaneous coinfection with SARS-CoV-2.

Recommendation — Since influenza infection in staff and patients is common, ranging between 25 and 80 percent, the CDC has published guidelines for the prevention and control of nosocomial influenza [71]. A central part of the prevention strategy is annual immunization of health care providers (ideally before the end of October), particularly clinicians, nurses, employees of nursing homes or other long-term health facilities who have contact with patients or residents, and providers of home care to high-risk patients [7,56,71]. In both adults and pediatric health care providers, influenza vaccine is cost effective and, in one study, reduced absenteeism by 28 percent [72].

In general, inactivated quadrivalent vaccines are preferred in health care settings. High-dose influenza vaccination is recommended for health care workers over age 65.

The intranasal live attenuated influenza vaccine (LAIV) is also an option for healthy nonpregnant adults up to 49 years of age; however, the ACIP recommends that health care providers caring for severely immunosuppressed individuals not receive the LAIV [71]. If a health care provider did receive intranasal vaccine, they should not have contact with severely immunosuppressed patients for seven days after vaccination. From 2016 through 2018, the ACIP recommended against the use of the intranasal LAIV for all persons, given its poor effectiveness against H1N1 in children in the 2013 to 2016 seasons, but subsequent vaccines have resulted in higher H1N1 antibody titers than the earlier strain [73].

If the inactivated quadrivalent vaccine formulation is not available and the health care worker is ineligible for LAIV, the inactivated trivalent formulation of the influenza vaccine should be used rather than delay vaccination.

More detailed discussions of the different vaccine formulations and the approach to vaccination in different populations (eg, older adults, pregnant persons, immunocompromised patients) are found elsewhere. (See "Seasonal influenza vaccination in adults", section on 'Formulations'.)

Measles, mumps, and rubella vaccine — There continue to be outbreaks of measles, mumps, and rubella cases globally, although the numbers vary from year to year. As an example, in the United States, there were 1282 cases of measles reported to the CDC in 2019, when there was an outbreak, but from January 1 to August 19, 2020, there were only been 12 cases reported [74]. (See "Measles: Epidemiology and transmission" and "Mumps", section on 'Epidemiology' and "Rubella", section on 'Epidemiology'.)

These diseases are a major health hazard for hospital personnel. All three are transmissible by the air-droplet route (and measles can also be transmitted by the airborne route) before the infected person has clinically recognizable illness. The risk of acquiring measles in hospital personnel is estimated to be 13 times greater than that of the general population [75]. In addition, nosocomial outbreaks of all three diseases have been reported [15,76-78]. Transmission of measles has occurred after visits to the emergency department [79] and in outpatient areas, even if the patient with measles had left the area more than one hour earlier [80,81]; there have also been reports of rubella being transmitted from children with congenital rubella [82].

Based upon these observations, health care providers are considered at high risk of exposure to measles, mumps, and rubella and need full immunity to these diseases (see "Measles, mumps, and rubella immunization in adults"). Although people born before 1957 have been considered immune to measles, 4 to 9 percent of health care providers born before 1957 were found to be susceptible to measles in outbreak investigations [78,83-85]. Similarly, approximately 6 percent of health care providers born before 1957 are susceptible to rubella [86].

Recommendation — All health care providers (medical with and without patient care responsibilities, non-medical, paid, volunteer, full-time, part-time, student) should have a formal assessment of immunity to measles and mumps regardless of year of birth and those who are susceptible should be immunized [7,20]. The same recommendation is made for all female health care providers with respect to rubella immunity and immunization [20]. Strict definitions of evidence of measles, mumps, and rubella immunity should be used. Serologic screening before immunization is generally not considered necessary for people who have documentation of appropriate vaccination or other acceptable evidence of immunity to measles, mumps, and rubella, such as laboratory confirmation of disease. Most individuals born prior to 1957 were likely infected naturally and can generally be presumed immune. However, for unvaccinated health care providers born before 1957 who lack laboratory evidence of measles or mumps immunity or laboratory confirmation of disease, vaccination with two doses of MMR given at least 28 days apart should be considered [7]. During outbreaks of measles or mumps, such individuals should receive two doses of MMR vaccine. (See "Measles, mumps, and rubella immunization in adults", section on 'Who should be immunized'.)

Two doses of the trivalent MMR vaccine are needed for full immunity. However, bivalent or monovalent vaccines can be used in health care providers who have acceptable evidence of immunity to one or two of the viruses. (See "Measles, mumps, and rubella immunization in adults".)

Since 1978, M-M-R II has been the only MMR vaccine available in the United States. In June 2022, the Advisory Committee on Immunization Practices (ACIP) recommended approval of a second MMR vaccine (sold as PRIORIX), which can be used interchangeably with M-M-R II [87]. However, completing the immunization series with the same vaccine is preferred, if possible. (See "Measles, mumps, and rubella immunization in adults", section on 'Vaccine formulations'.)

Pertussis vaccine — Pertussis is highly contagious with secondary attack rates among susceptible household contacts of more than 80 percent [88]. Despite widespread use of diphtheria, pertussis, and tetanus immunization of children, the incidence of pertussis has been increasing. There were 25,827 cases reported in 2004 (the largest number since 1959) and 16,858 cases in 2009, with localized outbreaks in California, Michigan and Ohio [89]. In addition, it is likely that the cases reported to the CDC are an underestimate, because many cases of pertussis are not diagnosed.

Although the highest attack rate of pertussis occurs in children under one year of age, approximately 60 percent of cases now occur in adults [90]. Survey data from the CDC found that Tdap coverage was less than 6 percent in adults [91,92]. In June 2012, the ACIP recommended that all adults, including those aged 65 and older, receive a dose of Tdap, regardless of the time since their last Td dose [93]. This recommendation is applicable to health care personnel, but health care personnel should receive Tdap as soon as feasible, if they have not previously received this vaccine. Two Tdap vaccines are approved in the United States for adults under age 65: Boostrix™ and ADACEL™. Because data are not available to evaluate the effectiveness of a single dose of Tdap for the prevention of secondary cases of pertussis, it is still recommended that exposed adults receive prophylaxis, as discussed elsewhere. (See "Pertussis infection in adolescents and adults: Treatment and prevention".)

Varicella vaccine — Control of varicella in the health care environment is important for two reasons: varicella is highly contagious, with secondary attack rates in susceptible household members varying from 61 to 87 percent [94]; and adults are at high risk of developing complications (see "Prevention and control of varicella-zoster virus in hospitals"). Immunocompromised adults and pregnant women are at particular risk of morbidity and mortality caused by varicella. (See "Immunizations in adults with cancer" and "Varicella-zoster virus infection in pregnancy".)

Person-to-person, droplet, and airborne transmission from either primary varicella or herpes zoster may be the way in which health care providers are exposed to the virus [95]. Nosocomial outbreaks continue to be reported [96-99], with source patients including those who did not have evidence of clinical disease at the time of transmission [100]. Even if patients with varicella can be promptly placed in negative pressure rooms, as recommended by the CDC [2], susceptible health care providers remain at risk of acquiring disease that is transmitted before clinical disease is apparent.

An estimated 14 to 40 percent of health care providers are susceptible to varicella. While 97 to 99 percent of those who have a positive history of varicella are seropositive, variable percentages of those with an unclear or no history of varicella are seropositive [86].

Recommendation — The CDC and many infectious diseases experts recommend the varicella vaccine for health care providers [86], because of the risk of serious complications of natural disease in adults, the risk of further transmission in health care facilities, and immunization is cost-effective [101]. The CDC and the American Academy of Pediatrics recommend that susceptible employees be removed from work beginning 8 to 10 days after exposure through day 21 after exposure [23,86]. Varicella control strategies other than immunization are reviewed elsewhere [2,86]. (See "Prevention and control of varicella-zoster virus in hospitals".)

Health care providers should be screened for varicella immunity. Those with a laboratory or health care provider confirmation of prior disease or written documentation of two varicella vaccine doses can be considered immune, but all others should have serologic testing, ideally with the latex agglutination test. Those who are seronegative who do not have a contraindication to immunization should be immunized with two doses of the varicella vaccine administered at least four weeks apart. (See "Prevention and control of varicella-zoster virus in hospitals", section on 'Prevention of varicella among health care personnel'.)

Post-immunization serology is not cost-effective because commercial tests lack the sensitivity to detect lower antibody levels associated with immunization and because more sensitive assays (such as the gpELISA test that is not commercially available) show that 99 percent of adults seroconvert after immunization. Secondary transmission of varicella after immunization has not yet occurred in the absence of a vesicular post-immunization rash [102]. Health care providers who develop an injection site rash may continue to work only if the lesions are covered. Employees who develop a generalized rash must be furloughed, since the rash may be caused by natural varicella, coincidentally associated with immunization.

Unfortunately, seroconversion does not always result in full protection against varicella. The management of health care providers following varicella exposure is discussed in detail elsewhere. (See "Prevention and control of varicella-zoster virus in hospitals", section on 'Management of exposed previously vaccinated health care workers' and "Prevention and control of varicella-zoster virus in hospitals", section on 'Management of exposed susceptible health care personnel'.)

Vaccines that may be indicated in specified settings

BCG vaccine — Since the risk of infection with M. tuberculosis is low and the efficacy of the Bacille Calmette-Guerin (BCG) vaccine is uncertain, routine immunization of health care providers is not recommended [86]. Another problem is that BCG vaccination interferes with the use of the tuberculin skin test that is used to detect infection with M. tuberculosis. (See "Prevention of tuberculosis: BCG immunization and nutritional supplementation".)

BCG vaccination may be considered in the following situations and only as a secondary prevention strategy after instituting comprehensive infection control practices [86]:

A high percentage of patients are infected with M. tuberculosis strains that are resistant to isoniazid and rifampin.

Transmission of drug-resistant strains of M. tuberculosis to health care providers is considered likely.

Comprehensive infection control precautions have been unsuccessfully implemented.

BCG vaccination is not recommended for health care providers in low-risk settings and is contraindicated in immunocompromised persons. (See "Immunizations in adults with cancer".)

Hepatitis A vaccine — Hepatitis A is highly endemic in the United States. The incidence appears to have been decreasing in recent years with 10,777 cases reported to the CDC in 2001 (provisional data) [103] compared with 31,582 cases in 1995. However, both reports underestimate the true burden of disease because of underreporting of symptomatic infection and lack of recognition of asymptomatic disease.

Even though hepatitis A is common, with 11 to 22 percent of symptomatic patients requiring hospitalization [104], nosocomial outbreaks are rare when proper infection control practices are followed [86,105]. Nosocomial outbreaks have been associated with contaminated blood transfusions [106,107], contaminated food [108,109], and poor infection control practices, particularly when caring for patients with fecal incontinence or unrecognized hepatitis A infection [110-113].

The primary strategy for preventing hepatitis A infection in health care providers is strict infection control practices. The hepatitis A vaccine is not routinely recommended for any group of health care providers. It may be provided on an individual basis for health care providers who have other risk factors for acquiring hepatitis A. (See "Hepatitis A virus infection: Treatment and prevention".)

Meningococcal vaccine — Nosocomial transmission of Neisseria meningitidis is rare, although direct contact with respiratory secretions of infected persons has resulted in transmission to health care providers [86]. The primary approach to prevention of acquisition of meningococcal disease is to adhere to precautions that prevent exposure to respiratory droplets [2,86]. (See "Treatment and prevention of meningococcal infection", section on 'Prevention'.)

Routine meningococcal vaccination of health care providers is not recommended. However, vaccination with the quadrivalent meningococcal conjugate vaccine and/or meningococcal serogroup B vaccine should be administered to those with other indications, such as complement component deficiencies or anatomic or functional asplenia (figure 1 and figure 2) [7]. Both vaccines should also be administered to laboratory personnel who work with N. meningitidis. (See "Meningococcal vaccination in children and adults", section on 'Immunization of persons at increased risk'.)

Meningococcal vaccination should also be used during outbreaks to reduce the number of secondary cases when there is an appropriate vaccine available for the outbreak serogroup [114]. In addition, those who have had extensive contact with oropharyngeal secretions of infected patients should receive antimicrobial prophylaxis. (See "Treatment and prevention of meningococcal infection", section on 'Antimicrobial chemoprophylaxis' and "Meningococcal vaccination in children and adults", section on 'Outbreak control'.)

Vaccines for other preventable diseases — Some immunizations are only warranted for selected health care providers who are at high risk of exposure to a specific pathogen (eg, Ebola virus, monkeypox virus). The approach to vaccination for such health care providers is discussed separately. (See "Treatment and prevention of Ebola virus disease", section on 'Ebola vaccines' and "Treatment and prevention of mpox (monkeypox)", section on 'Persons with occupational risk'.)

There are also many routine vaccine preventable diseases that are not related to occupational exposures, such as pneumococcal infection. Health care providers should receive these immunizations according to the schedule recommended for healthy adults (figure 1 and figure 2). (See "Standard immunizations for nonpregnant adults".)

APPROACH TO POST-EXPOSURE PROPHYLAXIS — Post-exposure prophylaxis is indicated for susceptible health care providers who are exposed to certain infections, such as hepatitis A, hepatitis B, HIV, influenza, measles, meningococcus, mpox, pertussis, and varicella. The indications and approach to post-exposure prophylaxis are discussed elsewhere.

(See "Prevention of hepatitis B virus and hepatitis C virus infection among health care providers".)

(See "Management of health care personnel exposed to HIV".)

(See "Hepatitis A virus infection: Treatment and prevention".)

(See "Prevention and control of varicella-zoster virus in hospitals".)f

(See "Measles, mumps, and rubella immunization in adults".)

(See "Seasonal influenza vaccination in adults".)

(See "Pertussis infection in adolescents and adults: Treatment and prevention".)

(See "Treatment and prevention of meningococcal infection".)

(See "Vaccines to prevent smallpox, mpox (monkeypox), and other orthopoxviruses".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Immunizations in adults".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

Basics topics (see "Patient education: Vaccines for adults (The Basics)" and "Patient education: What you should know about vaccines (The Basics)")

Beyond the Basics topic (see "Patient education: Vaccines for adults (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

All medical facilities or health departments that provide direct patient care are encouraged to formulate and implement a comprehensive immunization policy for all health care providers (figure 1 and figure 2). (See 'Immunization policies' above.)

Unless the health care provider has a contraindication to vaccine administration, immunization is recommended when prior vaccine administration cannot be documented. (See 'Medical documentation' above.)

Failure to immunize is often related to either refusal of the health care provider (because of concerns regarding side effects or failure to recognize risk) or because of inadequate enforcement of immunization policy. (See 'Failure to immunize' above.)

The introduction of hepatitis B immunization among health care providers in the 1980s has resulted in substantial decrease in the number of hepatitis B infections. Protective titers (anti-HBs >10 milli-international units/mL) develop in approximately 90 percent of healthy adults who receive three intramuscular doses of hepatitis B vaccine. All health care providers should have serologic testing one to two months after immunization. (See 'Hepatitis B vaccine' above.)

All health care providers should be immune to measles, mumps, and rubella, which have been associated with nosocomial outbreaks. Based upon these observations, health care providers are considered at high risk of exposure to measles, mumps, and rubella and need full immunity to these diseases. Serologic screening before immunization is generally not considered necessary for people who have documentation of appropriate vaccination, prior serologic testing, or laboratory confirmation of prior infection. (See 'Measles, mumps, and rubella vaccine' above.)

Influenza vaccination of health care providers reduces absenteeism and transmission of infection to hospitalized patients and is recommended annually for all health care providers. (See 'Influenza vaccine' above.)

Health care providers can acquire varicella infection through person-to-person, droplet, or airborne transmission from a patient with either primary varicella or herpes zoster. Varicella vaccine is recommended for non-immune health care providers because of the risk of serious complications of natural disease in adults and the risk of further transmission in health care facilities. Those with a history of varicella infection can be considered immune, but all others should have serologic testing. (See "Measles, mumps, and rubella immunization in adults".)

Pertussis is highly contagious; transmission occurs by direct contact with respiratory secretions or large aerosol droplets. Due to the recognition of waning immunity in adults, documented nosocomial outbreaks, and the availability of a safe and effective vaccine, health care personnel who have direct patient contact should receive a single dose of Tdap (tetanus-diphtheria-acellular pertussis) as soon as feasible, if they have not previously received this vaccine. (See 'Vaccines that may be indicated in specified settings' above.)

  1. Larson EL. APIC guideline for handwashing and hand antisepsis in health care settings. Am J Infect Control 1995; 23:251.
  2. Garner JS. Guideline for isolation precautions in hospitals. The Hospital Infection Control Practices Advisory Committee. Infect Control Hosp Epidemiol 1996; 17:53.
  3. National Committee for Clinical Laboratory Standards. Protection of laboratory workers from infectious diseases transmitted by blood, body fluids, and tissue: Tentative guideline. NCCLS Document M29-T2, 1991; 11(No. l4):l.
  4. Centers for Disease Control. Biosafety in microbiological and biomedical laboratories. HHS Publication No. 93-8595. Government Printing Office, Washington, DC, 1995.
  5. Flemming DO, Richardson JH, Tulis JJ, Vesley D. Laboratory Safety, Second Edition, ASM Press, Washington, DC 1995.
  6. Corbett EL, Muzangwa J, Chaka K, et al. Nursing and community rates of Mycobacterium tuberculosis infection among students in Harare, Zimbabwe. Clin Infect Dis 2007; 44:317.
  7. Advisory Committee on Immunization Practices, Centers for Disease Control and Prevention (CDC). Immunization of health-care personnel: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep 2011; 60:1.
  8. Centers for Disease Control (CDC). Pilot study of a household survey to determine HIV seroprevalence. MMWR Morb Mortal Wkly Rep 1991; 40:1.
  9. L'Ecuyer PB, Miller M, Winters K, Fraser VJ. Tuberculosis, hepatitis B, rubella, rubeola, and varicella infection and immunity among medical school employees. Infect Control Hosp Epidemiol 1998; 19:915.
  10. Shapiro CN, Tokars JI, Chamberland ME. Use of the hepatitis-B vaccine and infection with hepatitis B and C among orthopaedic surgeons. The American Academy of Orthopaedic Surgeons Serosurvey Study Committee. J Bone Joint Surg Am 1996; 78:1791.
  11. Panlilio AL, Shapiro CN, Schable CA, et al. Serosurvey of human immunodeficiency virus, hepatitis B virus, and hepatitis C virus infection among hospital-based surgeons. Serosurvey Study Group. J Am Coll Surg 1995; 180:16.
  12. Agerton TB, Mahoney FJ, Polish LB, Shapiro CN. Impact of the bloodborne pathogens standard on vaccination of healthcare workers with hepatitis B vaccine. Infect Control Hosp Epidemiol 1995; 16:287.
  13. McArthur MA, Simor AE, Campbell B, McGeer A. Influenza and pneumococcal vaccination and tuberculin skin testing programs in long-term care facilities: where do we stand? Infect Control Hosp Epidemiol 1995; 16:18.
  14. Nichol KL, Hauge M. Influenza vaccination of healthcare workers. Infect Control Hosp Epidemiol 1997; 18:189.
  15. Steingart KR, Thomas AR, Dykewicz CA, Redd SC. Transmission of measles virus in healthcare settings during a communitywide outbreak. Infect Control Hosp Epidemiol 1999; 20:115.
  16. Christian MA. Influenza and hepatitis B vaccine acceptance: a survey of health care workers. Am J Infect Control 1991; 19:177.
  17. Doebbeling BN, Edmond MB, Davis CS, et al. Influenza vaccination of health care workers: evaluation of factors that are important in acceptance. Prev Med 1997; 26:68.
  18. Lane NE, Paul RI, Bratcher DF, Stover BH. A survey of policies at children's hospitals regarding immunity of healthcare workers: are physicians protected? Infect Control Hosp Epidemiol 1997; 18:400.
  19. Adal KA, Flowers RH, Anglim AM, et al. Prevention of nosocomial influenza. Infect Control Hosp Epidemiol 1996; 17:641.
  20. Bolyard EA, Tablan OC, Williams WW, et al. Guideline for infection control in healthcare personnel, 1998. Hospital Infection Control Practices Advisory Committee. Infect Control Hosp Epidemiol 1998; 19:407.
  21. DeCastro MG, Denys GA, Fauerbach LL, et al. APIC position paper: immunization. Association for Professionals in Infection and Epidemiology, Inc. Am J Infect Control 1999; 27:52.
  22. American College of Physicians Task Force on Adult Immunization and Infectious Disease Society of America. In: Guide for Adult Immunization, Third Edition, American College of Physicians, Philadelphia p.1994.
  23. American Academy of Pediatrics. Health care personnel. In: Red Book: 2009 Report of the Committee on Infectious Diseases, 28th Edition, Pickering LK (Ed), American Academy of Pediatrics, Elk Grove Village, IL 2009. p.94.
  24. Krause PJ, Gross PA, Barrett TL, et al. Quality standard for assurance of measles immunity among health care workers. The Infectious Diseases Society of America. Infect Control Hosp Epidemiol 1994; 15:193.
  25. Poland GA, Haiduven DJ. Adult immunizations in the health-care worker. In: APIC Infection Control and Applied Epidemiology, Olmsted R (Ed), Mosby, St. Louis 1996. p.24.
  26. Beekmann SE, Doebbeling BN. Frontiers of occupational health. New vaccines, new prophylactic regimens, and management of the HIV-infected worker. Infect Dis Clin North Am 1997; 11:313.
  27. Weber DJ, Rutala WA, Weigle K. Selection and use of vaccines for healthcare workers. Infect Control Hosp Epidemiol 1997; 18:682.
  28. Mahoney FJ, Stewart K, Hu H, et al. Progress toward the elimination of hepatitis B virus transmission among health care workers in the United States. Arch Intern Med 1997; 157:2601.
  29. Kew MC. Possible transmission of serum (Australia-antigen-positive) hepatitis via the conjunctiva. Infect Immun 1973; 7:823.
  30. Snydman DR, Hindman SH, Wineland MD, et al. Nosocomial viral hepatitis B. A cluster among staff with subsequent transmission to patients. Ann Intern Med 1976; 85:573.
  31. Ingerslev J, Mortensen E, Rasmussen K, et al. Silent hepatitis-B immunization in laboratory technicians. Scand J Clin Lab Invest 1988; 48:333.
  32. Centers for Disease Control (CDC). Hepatitis B associated with jet gun injection--California. MMWR Morb Mortal Wkly Rep 1986; 35:373.
  33. Morris IM, Cattle DS, Smits BJ. Letter: Endoscopy and transmission of hepatitis B. Lancet 1975; 2:1152.
  34. Oren I, Hershow RC, Ben-Porath E, et al. A common-source outbreak of fulminant hepatitis B in a hospital. Ann Intern Med 1989; 110:691.
  35. Centers for Disease Control (CDC). Nosocomial transmission of hepatitis B virus associated with a spring-loaded fingerstick device--California. MMWR Morb Mortal Wkly Rep 1990; 39:610.
  36. Polish LB, Shapiro CN, Bauer F, et al. Nosocomial transmission of hepatitis B virus associated with the use of a spring-loaded finger-stick device. N Engl J Med 1992; 326:721.
  37. Centers for Disease Control and Prevention (CDC). Nosocomial hepatitis B virus infection associated with reusable fingerstick blood sampling devices--Ohio and New York City, 1996. MMWR Morb Mortal Wkly Rep 1997; 46:217.
  38. Lauer JL, VanDrunen NA, Washburn JW, Balfour HH Jr. Transmission of hepatitis B virus in clinical laboratory areas. J Infect Dis 1979; 140:513.
  39. Pattison CP, Boyer DM, Maynard JE, Kelly PC. Epidemic hepatitis in a clinical laboratory. Possible association with computer card handling. JAMA 1974; 230:854.
  40. Tanaka S, Yoshiba M, Iino S, et al. A common-source outbreak of fulminant hepatitis B in hemodialysis patients induced by precore mutant. Kidney Int 1995; 48:1972.
  41. Centers for Disease Control and Prevention (CDC). Outbreaks of hepatitis B virus infection among hemodialysis patients-- California, Nebraska, and Texas, 1994. MMWR Morb Mortal Wkly Rep 1996; 45:285.
  42. Department of Labor. Bloodborne pathogens: the standard. Federal Register 1991; 60:64175.
  43. Schillie S, Murphy TV, Sawyer M, et al. CDC guidance for evaluating health-care personnel for hepatitis B virus protection and for administering postexposure management. MMWR Recomm Rep 2013; 62:1.
  44. Schillie S, Vellozzi C, Reingold A, et al. Prevention of Hepatitis B Virus Infection in the United States: Recommendations of the Advisory Committee on Immunization Practices. MMWR Recomm Rep 2018; 67:1.
  45. Beltrami EM, Williams IT, Shapiro CN, Chamberland ME. Risk and management of blood-borne infections in health care workers. Clin Microbiol Rev 2000; 13:385.
  46. Cleveland JL, Cardo DM. Occupational exposures to human immunodeficiency virus, hepatitis B virus, and hepatitis C virus: risk, prevention, and management. Dent Clin North Am 2003; 47:681.
  47. Beekmann SE, Henderson DK. Protection of healthcare workers from bloodborne pathogens. Curr Opin Infect Dis 2005; 18:331.
  48. Gara N, Abdalla A, Rivera E, et al. Durability of antibody response against hepatitis B virus in healthcare workers vaccinated as adults. Clin Infect Dis 2015; 60:505.
  49. Hadler SC, Margolis HS. Hepatitis B immunization: vaccine types, efficacy, and indications for immunization. In: Current topics in infectious diseases, Remington JS, Swartz MN (Eds), Blackwell Science, Boston 1992. p.282.
  50. Schillie S, Harris A, Link-Gelles R, et al. Recommendations of the Advisory Committee on Immunization Practices for Use of a Hepatitis B Vaccine with a Novel Adjuvant. MMWR Morb Mortal Wkly Rep 2018; 67:455.
  51. Havlichek D Jr, Rosenman K, Simms M, Guss P. Age-related hepatitis B seroconversion rates in health care workers. Am J Infect Control 1997; 25:418.
  52. Louther J, Feldman J, Rivera P, et al. Hepatitis B vaccination program at a New York City hospital: seroprevalence, seroconversion, and declination. Am J Infect Control 1998; 26:423.
  53. Lemon SM, Thomas DL. Vaccines to prevent viral hepatitis. N Engl J Med 1997; 336:196.
  54. Alimonos K, Nafziger AN, Murray J, Bertino JS Jr. Prediction of response to hepatitis B vaccine in health care workers: whose titers of antibody to hepatitis B surface antigen should be determined after a three-dose series, and what are the implications in terms of cost-effectiveness? Clin Infect Dis 1998; 26:566.
  55. Hepatitis B virus: a comprehensive strategy for eliminating transmission in the United States through universal childhood vaccination. Recommendations of the Immunization Practices Advisory Committee (ACIP). MMWR Recomm Rep 1991; 40:1.
  56. The Centers for Disease Control and Prevention. Prevention Strategies for Seasonal Influenza in Healthcare Settings http://www.cdc.gov/flu/professionals/infectioncontrol/healthcaresettings.htm (Accessed on October 10, 2018).
  57. Balkovic ES, Goodman RA, Rose FB, Borel CO. Nosocomial influenza A (H1N1) infection. Am J Med Technol 1980; 46:318.
  58. Van Voris LP, Belshe RB, Shaffer JL. Nosocomial influenza B virus infection in the elderly. Ann Intern Med 1982; 96:153.
  59. Centers for Disease Control (CDC). Suspected nosocomial influenza cases in an intensive care unit. MMWR Morb Mortal Wkly Rep 1988; 37:3.
  60. Pachucki CT, Pappas SA, Fuller GF, et al. Influenza A among hospital personnel and patients. Implications for recognition, prevention, and control. Arch Intern Med 1989; 149:77.
  61. Hammond GW, Cheang M. Absenteeism among hospital staff during an influenza epidemic: implications for immunoprophylaxis. Can Med Assoc J 1984; 131:449.
  62. Patriarca PA, Weber JA, Parker RA, et al. Risk factors for outbreaks of influenza in nursing homes. A case-control study. Am J Epidemiol 1986; 124:114.
  63. Gross PA, Rodstein M, LaMontagne JR, et al. Epidemiology of acute respiratory illness during an influenza outbreak in a nursing home. A prospective study. Arch Intern Med 1988; 148:559.
  64. Cartter ML, Renzullo PO, Helgerson SD, et al. Influenza outbreaks in nursing homes: how effective is influenza vaccine in the institutionalized elderly? Infect Control Hosp Epidemiol 1990; 11:473.
  65. Arroyo JC, Postic B, Brown A, et al. Influenza A/Philippines/2/82 outbreak in a nursing home: limitations of influenza vaccination in the aged. Am J Infect Control 1984; 12:329.
  66. Christie RW, Marquis LL. Immunization roulette: influenza occurrence in five nursing homes. Am J Infect Control 1985; 13:174.
  67. Atkinson WL, Arden NH, Patriarca PA, et al. Amantadine prophylaxis during an institutional outbreak of type A (H1N1) influenza. Arch Intern Med 1986; 146:1751.
  68. Centers for Disease Control (CDC). Outbreak of influenza A in a nursing home--New York, December 1991-January 1992. MMWR Morb Mortal Wkly Rep 1992; 41:129.
  69. Potter J, Stott DJ, Roberts MA, et al. Influenza vaccination of health care workers in long-term-care hospitals reduces the mortality of elderly patients. J Infect Dis 1997; 175:1.
  70. Ahmed F, Lindley MC, Allred N, et al. Effect of influenza vaccination of healthcare personnel on morbidity and mortality among patients: systematic review and grading of evidence. Clin Infect Dis 2014; 58:50.
  71. Grohskopf LA, Alyanak E, Broder KR, et al. Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices - United States, 2020-21 Influenza Season. MMWR Recomm Rep 2020; 69:1.
  72. Saxén H, Virtanen M. Randomized, placebo-controlled double blind study on the efficacy of influenza immunization on absenteeism of health care workers. Pediatr Infect Dis J 1999; 18:779.
  73. Grohskopf LA, Sokolow LZ, Fry AM, et al. Update: ACIP Recommendations for the Use of Quadrivalent Live Attenuated Influenza Vaccine (LAIV4) - United States, 2018-19 Influenza Season. MMWR Morb Mortal Wkly Rep 2018; 67:643.
  74. Centers for Disease Control and Prevention. Measles (Rubeola): Measles Cases and Outbreaks. http://www.cdc.gov/measles/cases-outbreaks.html (Accessed on May 07, 2015).
  75. Williams WW, Preblud SR, Reichelderfer PS, Hadler SC. Vaccines of importance in the hospital setting. Problems and developments. Infect Dis Clin North Am 1989; 3:701.
  76. Fischer PR, Brunetti C, Welch V, Christenson JC. Nosocomial mumps: report of an outbreak and its control. Am J Infect Control 1996; 24:13.
  77. McGrath D, Swanson R, Weems S, et al. Analysis of a measles outbreak in Kent County, Michigan in 1990. Pediatr Infect Dis J 1992; 11:385.
  78. Rivera ME, Mason WH, Ross LA, Wright HT Jr. Nosocomial measles infection in a pediatric hospital during a community-wide epidemic. J Pediatr 1991; 119:183.
  79. Miranda AC, Falcão J, Dias JA, et al. Measles transmission in health facilities during outbreaks. Int J Epidemiol 1994; 23:843.
  80. Remington PL, Hall WN, Davis IH, et al. Airborne transmission of measles in a physician's office. JAMA 1985; 253:1574.
  81. Bloch AB, Orenstein WA, Ewing WM, et al. Measles outbreak in a pediatric practice: airborne transmission in an office setting. Pediatrics 1985; 75:676.
  82. Centers for Disease Control (CDC). Nosocomial rubella infection - North Dakota, Alabama, Ohio. MMWR Morb Mortal Wkly Rep 1981; 29:630.
  83. Watkins NM, Smith RP Jr, St Germain DL, MacKay DN. Measles (rubeola) infection in a hospital setting. Am J Infect Control 1987; 15:201.
  84. Braunstein H, Thomas S, Ito R. Immunity to measles in a large population of varying age. Significance with respect to vaccination. Am J Dis Child 1990; 144:296.
  85. Smith E, Wong VK. Measles susceptibility of hospital personnel. Arch Intern Med 1993; 153:1011.
  86. Immunization of health-care workers: recommendations of the Advisory Committee on Immunization Practices (ACIP) and the Hospital Infection Control Practices Advisory Committee (HICPAC). MMWR Recomm Rep 1997; 46:1.
  87. Measles, Mumps, Rubella Vaccine (PRIORIX): Recommendations of the Advisory Committee on Immunization Practices — United States, 2022. Centers for Disease Control and Prevention. Available at: https://www.cdc.gov/mmwr/volumes/71/wr/pdfs/mm7146-h.pdf. (Accessed on December 11, 2022).
  88. Mortimer EA Jr. Pertussis and its prevention: a family affair. J Infect Dis 1990; 161:473.
  89. http://www.cdc.gov/pertussis/outbreaks.html (Accessed on July 06, 2011).
  90. http://www.cdc.gov/vaccines/pubs/pinkbook/downloads/pert.pdf (Accessed on July 06, 2011).
  91. Centers for Disease Control and Prevention (CDC). National, state, and local area vaccination coverage among adolescents aged 13-17 years --- United States, 2009. MMWR Morb Mortal Wkly Rep 2010; 59:1018.
  92. Centers for Disease Control and Prevention (CDC). Tetanus and pertussis vaccination coverage among adults aged ≥ 18 years --- United States, 1999 and 2008. MMWR Morb Mortal Wkly Rep 2010; 59:1302.
  93. Centers for Disease Control and Prevention (CDC). Updated recommendations for use of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine in adults aged 65 years and older - Advisory Committee on Immunization Practices (ACIP), 2012. MMWR Morb Mortal Wkly Rep 2012; 61:468.
  94. Josephson A, Karanfil L, Gombert ME. Strategies for the management of varicella-susceptible healthcare workers after a known exposure. Infect Control Hosp Epidemiol 1990; 11:309.
  95. Weber DJ, Rutala WA, Parham C. Impact and costs of varicella prevention in a university hospital. Am J Public Health 1988; 78:19.
  96. Josephson A, Gombert ME. Airborne transmission of nosocomial varicella from localized zoster. J Infect Dis 1988; 158:238.
  97. Varicella and zoster in hospitals. Lancet 1990; 335:1460.
  98. Friedman CA, Temple DM, Robbins KK, et al. Outbreak and control of varicella in a neonatal intensive care unit. Pediatr Infect Dis J 1994; 13:152.
  99. Faoagali JL, Darcy D. Chickenpox outbreak among the staff of a large, urban adult hospital: costs of monitoring and control. Am J Infect Control 1995; 23:247.
  100. Krasinski K, Holzman RS, LaCouture R, Florman A. Hospital experience with varicella-zoster virus. Infect Control 1986; 7:312.
  101. Nettleman MD, Schmid M. Controlling varicella in the healthcare setting: the cost effectiveness of using varicella vaccine in healthcare workers. Infect Control Hosp Epidemiol 1997; 18:504.
  102. Prevention of varicella. Update recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep 1999; 48:1.
  103. wonder.cdc.gov/mmwr/mmwr_reps.asp?mmwr_table=3A&mmwr_year=2001&mmwr_week=52 (Accessed on October 14, 2011).
  104. Centers for Disease Control. Hepatitis Surveillance Report No. 56. Public Health Service, Centers for Disease Control. Atlanta, US Department of Health and Human Services, 1996.
  105. Papaevangelou GJ, Roumeliotou-Karayannis AJ, Contoyannis PC. The risk of nosocomial hepatitis A and B virus infections from patients under care without isolation precaution. J Med Virol 1981; 7:143.
  106. Rosenblum LS, Villarino ME, Nainan OV, et al. Hepatitis A outbreak in a neonatal intensive care unit: risk factors for transmission and evidence of prolonged viral excretion among preterm infants. J Infect Dis 1991; 164:476.
  107. Lee KK, Vargo LR, Lê CT, Fernando L. Transfusion-acquired hepatitis A outbreak from fresh frozen plasma in a neonatal intensive care unit. Pediatr Infect Dis J 1992; 11:122.
  108. EISENSTEIN AB, AACH RD, JACOBSOHN W, GOLDMAN A. AN EPIDEMIC OF INFECTIOUS HEPATITIS IN A GENERAL HOSPITAL. PROBABLE TRANSMISSION BY CONTAMINATED ORANGE JUICE. JAMA 1963; 185:171.
  109. Meyers JD, Romm FJ, Tihen WS, Bryan JA. Food-borne hepatitis A in a general hospital. Epidemiologic study of an outbreak attributed to sandwiches. JAMA 1975; 231:1049.
  110. Watson JC, Fleming DW, Borella AJ, et al. Vertical transmission of hepatitis A resulting in an outbreak in a neonatal intensive care unit. J Infect Dis 1993; 167:567.
  111. Doebbeling BN, Li N, Wenzel RP. An outbreak of hepatitis A among health care workers: risk factors for transmission. Am J Public Health 1993; 83:1679.
  112. Burkholder BT, Coronado VG, Brown J, et al. Nosocomial transmission of hepatitis A in a pediatric hospital traced to an anti-hepatitis A virus-negative patient with immunodeficiency. Pediatr Infect Dis J 1995; 14:261.
  113. Hanna JN, Loewenthal MR, Negel P, Wenck DJ. An outbreak of hepatitis A in an intensive care unit. Anaesth Intensive Care 1996; 24:440.
  114. Centers for Disease Control and Prevention. Guidance for the Evaluation and Public Health Management of Suspected Outbreaks of Meningococcal Disease version 2.0. September 2019. https://www.cdc.gov/meningococcal/downloads/meningococcal-outbreak-guidance.pdf (Accessed on October 21, 2020).
Topic 3889 Version 30.0

References

آیا می خواهید مدیلیب را به صفحه اصلی خود اضافه کنید؟