Acute viral gastroenteritis in children in resource-abundant countries: Management and prevention

INTRODUCTION — The prevention and treatment of viral gastroenteritis in children in resource-abundant countries will be reviewed here. The epidemiology, clinical features, and diagnosis of acute viral gastroenteritis in children in resource-abundant countries; acute diarrhea in children in resource-limited countries; and chronic diarrhea in children are discussed separately.

●(See "Acute viral gastroenteritis in children in resource-abundant countries: Clinical features and diagnosis".)

●(See "Approach to the child with acute diarrhea in resource-limited settings".)

●(See "Overview of the causes of chronic diarrhea in children in resource-abundant settings" and "Approach to chronic diarrhea in children >6 months in resource-abundant settings" and "Persistent diarrhea in children in resource-limited settings".)

DEFINITION — Acute gastroenteritis is a clinical syndrome often defined by increased stool frequency (eg, ≥3 loose or watery stools in 24 hours or a number of loose/watery bowel movements that exceeds the child's usual number of daily bowel movements by two or more), with or without vomiting or fever [1-4]. It usually lasts less than one week and not longer than two weeks. Diarrhea that lasts >14 days is "persistent" or "chronic." Diarrhea that recurs after seven days without diarrhea is "recurrent."

Acute viral gastroenteritis is caused by a viral pathogen. Acute gastroenteritis also may be caused by bacteria and parasites. (See "Acute viral gastroenteritis in children in resource-abundant countries: Clinical features and diagnosis", section on 'Etiology' and "Acute viral gastroenteritis in children in resource-abundant countries: Clinical features and diagnosis", section on 'Bacterial or parasitic gastroenteritis'.)

MANAGEMENT — Acute viral gastroenteritis usually is self-limited. It is treated with supportive measures (eg, fluid repletion and unrestricted diet) [1,3]. Antimicrobial agents are not indicated in the management of acute viral gastroenteritis. No specific antiviral agents are available, and other antimicrobial agents are ineffective and associated with increased costs and potential for antimicrobial resistance.

The recommendations provided below are generally consistent with those provided by the Centers for Disease Control and Prevention (CDC), the Infectious Diseases Society of America (IDSA), the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN), the European Society for Pediatric Infectious Diseases, and other professional organizations [1-3,5,6].

Severity assessment

Degree of volume depletion — The severity of acute gastroenteritis is determined by the degree of volume depletion (table 1) [1,3]. Weight loss, dry mucous membranes, prolonged capillary refill time, loss of skin turgor, and increased and deep respiratory pattern are the best individual signs of hypovolemia. Other important signs that require immediate attention include increased pulse, diminished systolic and/or diastolic blood pressure, and sunken fontanel (in children whose fontanel remains open) (table 1). Fever is common in viral gastroenteritis and can aggravate loss of fluids, particularly if high (eg, ≥39°C [102.2°F]). (See "Clinical assessment of hypovolemia (dehydration) in children", section on 'Clinical assessment'.)

Laboratory studies to evaluate the severity of hypovolemia are discussed separately. (See "Clinical assessment of hypovolemia (dehydration) in children", section on 'Laboratory testing'.)

Indications for hospitalization — Indications for hospitalization of children with acute viral gastroenteritis include [1,2,7,8]:

●Shock (see "Initial evaluation of shock in children" and "Shock in children in resource-abundant settings: Initial management")

●Severe volume depletion (table 1)

●Moderate volume depletion with refusal of oral fluids

●Clinical deterioration

●Intractable or bilious vomiting

●Failure of oral rehydration

●Neurologic abnormalities (eg, lethargy, seizures)

●Possibility of severe illness or condition other than acute gastroenteritis that requires specific therapy (eg, bowel obstruction (table 2)) (see "Acute viral gastroenteritis in children in resource-abundant countries: Clinical features and diagnosis", section on 'Differential diagnosis')

●Inability to assure adequate home management and outpatient follow-up

Supportive treatment — Acute viral gastroenteritis usually is self-limited. It is treated with supportive measures [1,3]. Fluid repletion and replacement of ongoing fluid losses are the goals of therapy, whether the child is managed at home, in the emergency department, or in the hospital.

Fluid repletion and maintenance — Initial therapy is directed toward correcting fluid deficit and electrolyte imbalance. Fluid repletion is based upon the degree of hypovolemia (dehydration) (table 1). Intravenous (IV) fluids should be administered if dehydration is severe or if the patient is unable to take oral solutions. (See "Clinical assessment of hypovolemia (dehydration) in children".)

●Severe dehydration – Severe hypovolemia requires rapid isotonic fluid resuscitation, which is discussed separately. (See "Treatment of hypovolemia (dehydration) in children in resource-abundant settings".)

●Mild to moderate dehydration – Oral rehydration therapy (ORT) is the preferred first-line treatment for fluid and electrolyte losses in children with mild to moderate dehydration from acute gastroenteritis. (See "Oral rehydration therapy", section on 'Clinical management'.)

Diet — We recommend resumption of an age-appropriate diet as tolerated as soon as rehydration is complete, in agreement with the CDC, IDSA, ESPGHAN, and other professional organizations [1-3,5,6,8]. Breastfeeding can continue during diarrhea.

Within the age-appropriate diet, complex carbohydrates, lean meats, yogurt, fruits, and vegetables are better tolerated than foods containing high levels of fats and simple sugars [3]. Foods high in simple sugars (eg, sugar sweetened beverages, some fruit juices) may increase stool output and the risk of hyponatremia because they increase the osmotic load and contain low concentrations of sodium and potassium [2,3,9]. Although commonly recommended in the past, the clear liquid and "BRAT" (bananas, rice, applesauce, and toast) diets are unnecessarily restrictive and provide suboptimal nutrition [1,3].

A meta-analysis of randomized trials of early versus late refeeding (within 12 hours of the start of rehydration or after 12 hours from the start of rehydration) in children with diarrhea found no difference between the groups in the number of children who needed unscheduled IV fluids, had episodes of vomiting, or developed persistent diarrhea [10]. Breastfeeding during oral rehydration appears to reduce the number, volume, and duration of diarrheal stools [11].

The lactose intolerance associated with acute viral gastroenteritis usually is mild and self-limiting [12,13], although a lactose-free diet may reduce the duration of diarrhea and the risk of treatment failure among children who are not breastfed. In a 2013 meta-analysis of 16 randomized and quasi-randomized trials from high- or middle-income countries (1467 patients), a lactose-free diet reduced the mean duration of diarrhea by 17.7 hours (95% CI 10.2-25.3 hours) [14]; however, most of the trials were inadequately blinded, and there was significant heterogeneity in patient populations. In pooled analysis of 18 trials (1470 patients), lactose-free diets also appeared to reduce the risk of treatment failure, which was variably defined as continued or worsening diarrhea/vomiting, need for additional rehydration, or continued weight loss (relative risk [RR] 0.52, 95% CI 0.39-0.68). Although not routinely recommended, a lactose-free diet may be warranted for severe cases requiring hospitalization. Breastfeeding and infant formula can be resumed as tolerated when severe dehydration is corrected and can continue without change as tolerated for the child with mild to moderate dehydration.

Symptomatic therapy — Viral gastroenteritis is usually an acute and self-limited disease that does not require pharmacologic therapy.

Antidiarrheal agents — We suggest that antidiarrheal agents not be routinely administered in the treatment of acute viral gastroenteritis. High-quality evidence of efficacy is lacking for most antidiarrheal agents and there is a potential for serious side effects, as discussed below [1,3,7].

●Antimotility drugs – Opiate receptor agonists, such as loperamide and diphenoxylate-atropine combinations, reduce intestinal motility. These drugs have potentially severe side effects, including lethargy, paralytic ileus, toxic megacolon, central nervous system depression, coma, and even death in less than 1 percent [15-18]. In addition, because they delay transit time, they can prolong the course of bacterial diarrheas, such as that caused by Shigella and Escherichia coli [19,20]. Whether this also is true in viral gastroenteritis is unknown.

●Antisecretory drugs – Antisecretory drugs include bismuth subsalicylate and racecadotril (acetorphan).

•Bismuth subsalicylate requires frequent dosing with limited efficacy [21] and has potential toxicity from salicylate absorption [22]. It should not be routinely used in the management of children with gastroenteritis [1].

•Racecadotril is an enkephalinase inhibitor with antisecretory actions. Whether it is beneficial in the management of acute viral gastroenteritis in children is uncertain. Although racecadotril appears to be safe, meta-analyses of randomized and quasi-randomized trials have inconsistent findings related to benefit, which may be related to inclusion of different trials [18,23,24]. The overall quality of the evidence is limited by inconsistent results, heterogeneity in patient populations and outcome measures, and methodologic shortcomings (eg, lack of concealment or blinding) [18,23,24].

The European guidelines suggest that racecadotril "can be considered" in the management of acute gastroenteritis [1]. Racecadotril is not available in the United States.

●Adsorbents – Adsorbents (eg, hydrated aluminomagnesium silicates such as smectite/diosmectite and attapulgite, and kaolin-pectin) have the potential to bind digestive mucus and toxins, and reduce water loss [25,26].

Smectite/diosmectite is an adsorbent that is commonly used in several European countries. A network meta-analysis of randomized and quasi-randomized trials comparing interventions for acute diarrhea and gastroenteritis found low-quality evidence that smectite reduced the duration of diarrhea by 23.9 hours (95% CI 17.0-30.8), without increased risk of adverse effects, compared with standard care or placebo [18]; however, another meta-analysis found it had no effect on hospitalization rate or need for intravenous therapy [27]. Combined therapy with smectite and zinc is discussed below. (See 'Zinc' below.)

The European guidelines suggest that diosmectite "can be considered" in the management of acute gastroenteritis [1].

There is no evidence from high-quality trials that attapulgite or kaolin-pectin is effective in the treatment of acute gastroenteritis in children [1,5,18].

Antiemetic agents

●Ondansetron

•Children who are not dehydrated – For the routine management of children with acute viral gastroenteritis who are not dehydrated, we suggest against ondansetron and other antiemetics. The benefits are unproven [28].

•Children with mild to moderate dehydration and vomiting that interferes with ORT – For children ≥6 months of age with suspected viral gastroenteritis, mild to moderate dehydration, and vomiting that interferes with ORT, we suggest ondansetron. Compared with placebo and other antiemetic agents, ondansetron stops vomiting and facilitates ORT; it also reduces the need for IV fluids [29-32]. (See "Oral rehydration therapy".)

The typical regimen is a single oral dose of ondansetron 0.15 mg/kg (maximum dose of 8 mg). Multiple doses and IV administration can increase the risk of diarrhea and other adverse effects (eg, arrhythmia) [33-35]. Repeated doses have not proven beneficial [29,36].

In a systematic review comparing a single dose of oral ondansetron with placebo, ondansetron increased cessation of vomiting within eight hours (82 versus 66 percent, RR 1.41, 95% CI 1.19-1.68; nine trials, 1748 participants), reduced ORT failure (19 versus 45 percent, RR 0.43, 95% CI 0.34-0.55; five trials, 679 participants), reduced the need for IV fluid (8 versus 19 percent, RR 0.44, 95% CI 0.34-0.57; eight trials, 1662 participants), and reduced rates of hospitalization within eight hours (7 versus 14 percent, RR 0.49, 95% CI 0.32-0.75; five trials, 823 participants) [32]. In a network meta-analysis of 24 randomized trials (3482 participants), ondansetron was superior to other antiemetics (domperidone, dexamethasone, dimenhydrinate, granisetron, metoclopramide) and placebo in relieving vomiting and preventing the need for IV fluids and hospitalization in children with acute gastroenteritis [31].

A single dose of oral ondansetron appears to be safe in children without risk factors for arrhythmia [34]. In meta-analyses of randomized trials, the adverse effects of ondansetron generally were similar to those of placebo, although cases of urticaria and increased frequency of diarrhea have been reported [30,31]. When used for other indications, common adverse effects of ondansetron include headache and constipation [37-40].

Ondansetron does not appear to mask the diagnosis of serious causes of vomiting. In large retrospective studies, receipt of ondansetron or a prescription for ondansetron in the emergency department was not associated with increased rates of hospitalization or return visit within 72 hours for a diagnosis other than acute gastroenteritis (eg, appendicitis, intussusception, bacteremia, pyelonephritis, small bowel obstruction, intracranial tumor, meningitis) [41-43].

Ondansetron should not be used in patients who have congenital long QT syndrome or who are at risk for malignant hyperthermia. Serious potential adverse effects of first-generation selective serotonin 5-HT₃ antagonists such as ondansetron include excessive serotonergic effect and arrhythmia [44-46]. Electrocardiogram monitoring may be warranted for children at risk for corrected QT interval (QTc) prolongation, including those with hypokalemia or hypomagnesemia, heart failure, or bradyarrhythmias, and in patients taking other medications that increase the risk of QTc prolongation (table 3) [34,47].

•Children with severe dehydration – Children with severe dehydration require IV hydration. (See "Treatment of hypovolemia (dehydration) in children in resource-abundant settings", section on 'Emergency fluid repletion phase'.)

Society guideline recommendations for ondansetron are inconsistent. The IDSA guidelines for the management of infectious diarrhea indicate that ondansetron may reduce the need for hospitalization for rehydration but increase stool volume [6]. They do not routinely recommend ondansetron for children younger than four years. The European Guidelines indicate that ondansetron (oral or IV) may be effective in young children with vomiting related to acute gastroenteritis, but additional safety information is necessary [1]. The Canadian Paediatric Society recommends that a single dose of oral ondansetron be considered for children ≥6 months age who present to the emergency department with vomiting related to suspected acute gastroenteritis who have mild to moderate dehydration or have failed ORT [48]. (See 'Society guideline links' below.)

●Other antiemetics – We avoid other antiemetics (eg, phenothiazines, antihistamines, dopamine receptor antagonists, glucocorticoids) in the treatment of acute gastroenteritis in children. Evidence to support their use is lacking and they may have adverse effects [31,49-51].

Phenothiazines (eg, promethazine, metoclopramide, prochlorperazine) have the potential to cause extrapyramidal reactions, including dystonic reaction and oculogyric crisis [52]. Promethazine is associated with an increased risk of respiratory depression. It should not be used in children younger than two years and should be used with caution in older children; concomitant administration of other drugs with respiratory depressant effects should be avoided [53].

Antihistamines (eg, dimenhydrinate) may be associated with adverse effects (eg, sedation, dizziness, restlessness). In a network meta-analysis of antiemetics for acute gastroenteritis in children, dimenhydrinate was the only antiemetic that had more side effects than placebo, predominantly somnolence [31].

Domperidone (a dopamine receptor antagonist) has been associated with serious ventricular arrhythmias and sudden cardiac death [54,55].

Probiotics and prebiotics — Probiotics are live microbes that have the potential to benefit the host by altering intestinal flora. Prebiotics are substrates that are selectively utilized by host microorganisms conferring a health benefit [56]; examples of prebiotics include fructooligosaccharides and inulin.

Probiotics have been considered as an adjunct to rehydration therapy [57]. Although we generally discourage probiotics and prebiotics, we make decisions on a case-by-case basis in children with acute viral gastroenteritis after discussing the potential benefits and harms with the patient's caregivers.

The evidence of benefit for specific strains is inconsistent and generally of low certainty [57,58]. A systematic review of randomized trials comparing a specified probiotic with placebo or no probiotic concluded that it was uncertain whether probiotics reduced the mean duration of diarrhea and that probiotics probably make little difference in the number of people who have diarrhea for ≥48 hours [58]. Although meta-analyses of randomized trials of specific probiotic strains suggest potential benefit in reducing the duration of diarrhea (by approximately one day) without increasing the risk of adverse effects [59-61], the included trials had marked heterogeneity (eg, dose, age, severity, geographic region) and most had high risk of bias [58,62]. In meta-analyses that included only trials of Lactobacillus rhamnosus GG at low risk of bias, no benefit was detected [59,63].

The benefit, if any, appears to be affected by the strain(s), dose, possibly the pathogen, and combination with prebiotics or other agents [5,7,18,64-66]. In pathogen-specific secondary analysis of patient-level data from two randomized trials in North America, neither L. rhamnosus GG nor a combination of L. rhamnosus/R0011 and Lactobacillus helveticus R0052 was found to decrease the severity of diarrhea due to the most common pathogens in children age 3 to 48 months; among children with adenovirus diarrhea, combination L. rhamnosus/R0011/L. helveticus R0052 appeared to reduce the number of diarrheal episodes [67]. The benefit also may be related to the source of the particular preparation, which affects quality control and shelf-life [65].

Safety is another factor to consider in the decision to use probiotics. The US Food and Drug Administration does not evaluate probiotic products, which may contain unlabeled ingredients or species that differ from those indicated on the label or be contaminated with fungi or other pathogens; the reporting of harms in randomized trials is often inadequate or lacking [3,68-72]. In addition, probiotics and prebiotics are not typically covered by insurance.

The optimal timing for administration is uncertain. The suggestion that effectiveness is increased with early administration is not supported by randomized trials [73-75].

If clinicians and caregivers decide to use probiotic/prebiotics, the ESPGHAN Working Group on probiotics/prebiotics suggests one of the following strains [57,76]:

●Saccharomyces boulardii 250 to 750 mg (10⁹ to 10¹⁰ colony-forming units [CFU])/day (typically for five to seven days) [18,60]

Combined therapy with S. boulardii and zinc is discussed below. (See 'Zinc' below.)

●L. rhamnosus GG >10¹⁰ CFU/day for five to seven days [59]

●Limosilactobacillus reuteri DSM 17938 1 to 4 x 10⁸ CFU/day for five days [61]

●L. rhamnosus 19070-2 combined with L. reuteri DSM 12246 2 x 10¹⁰ CFU of each strain/day for five days

The ESPGHAN makes a strong recommendation against L. helveticus R0052 combined with L. rhamnosus R0011 based on moderate certainty evidence that the combination has no effect on duration of diarrhea and a weak recommendation against Bacillus clausii strains based on low certainty evidence [57,77].

The IDSA guidelines suggest that probiotics may be offered to reduce symptoms' severity in children with infectious diarrhea [6]. The 2014 European guidelines suggest that administration of effective probiotic strains "may be considered" in children admitted with acute gastroenteritis [1]. Other professional groups acknowledge the low-quality evidence suggesting a benefit to probiotics (specifically L. rhamnosus GG ) early in the course of acute viral gastroenteritis, but do not make recommendations for or against their use [5,7,64].

Zinc — We suggest not using zinc (alone or in combination with other agents) in the management of acute viral gastroenteritis in children in resource-abundant countries, where zinc deficiency is rare and no benefit from zinc is expected [1]. In a network meta-analysis of randomized and quasi-randomized trials comparing interventions for acute diarrhea and gastroenteritis, zinc was not found to be effective in reducing the duration of diarrhea in children in high-income countries [18]. Although there was moderate-quality evidence that the combination of zinc and S. boulardii or zinc and smectite reduced the duration of diarrhea by >35 hours, all of the included trials were performed in low- and middle-income countries.

Zinc supplementation for the treatment of children with acute diarrhea in resource-poor countries is discussed separately. (See "Zinc deficiency and supplementation in children", section on 'Treatment of acute or persistent diarrhea'.)

Response to therapy

Monitoring response — The child must be evaluated to ensure the volume status is correcting properly. Response to fluid therapy is assessed by measuring body weight with a goal of:

●Return to premorbid body weight for children with acute viral gastroenteritis complicated by volume depletion

●Maintenance of body weight for children with acute viral gastroenteritis without volume depletion

Serum electrolytes should be monitored in children with hypernatremia or hyponatremia. It is important to correct these electrolyte abnormalities at the proper rate. Monitoring response to therapy for children receiving IV fluids is discussed separately. (See "Treatment of hypovolemia (dehydration) in children in resource-abundant settings" and "Acid-base and electrolyte abnormalities with diarrhea" and "Hypernatremia in children", section on 'Rate of correction'.)

Expected response — With appropriate fluid repletion, maintenance of hydration, and timely reintroduction of an age-appropriate diet, most children with acute viral gastroenteritis recover completely. Parents and caregivers should understand that diarrhea may last for ≥7 days and may continue after discharge from medical care.

Failure to respond or worsening — Conditions other than acute viral gastroenteritis must be considered in children who fail to respond to fluid therapy or whose clinical condition worsens despite fluid therapy. The extent and pace of the evaluation for these conditions depends upon the clinical status of the child. It is particularly important to consider life-threatening conditions that can mimic acute viral gastroenteritis, including those listed below (see "Acute viral gastroenteritis in children in resource-abundant countries: Clinical features and diagnosis", section on 'Differential diagnosis' and "Diagnostic approach to diarrhea in children in resource-abundant settings" and "Approach to the infant or child with nausea and vomiting"):

●Intestinal obstruction (eg, appendicitis, intussusception, pyloric stenosis, malrotation) (see "Acute appendicitis in children: Clinical manifestations and diagnosis" and "Intussusception in children" and "Infantile hypertrophic pyloric stenosis" and "Intestinal malrotation in children")

●Metabolic disease (including diabetic ketoacidosis) (see "Diabetic ketoacidosis in children: Clinical features and diagnosis", section on 'Clinical features')

●Clostridioides difficile colitis and/or pseudomembranous colitis (see "Clostridioides difficile infection in children: Clinical features and diagnosis")

●Enterocolitis and toxic megacolon (which may occur as a complication of Hirschsprung disease, inflammatory bowel disease, and infectious colitis) (see "Toxic megacolon")

●Congenital secretory and osmotic diarrheas (see "Approach to chronic diarrhea in neonates and young infants (<6 months)")

Persistent symptoms — Conditions that cause persistent, recurrent, or chronic diarrhea should be considered in children who continue to have diarrhea for longer than seven days. Causes of chronic diarrhea and the approach to the evaluation of chronic diarrhea in children in resource-abundant countries are discussed separately. (See "Overview of the causes of chronic diarrhea in children in resource-abundant settings" and "Approach to chronic diarrhea in children >6 months in resource-abundant settings".)

Discharge from the medical setting — For children who are admitted to the hospital for IV fluid repletion or cared for in a medical setting (eg, emergency department, office), minimum criteria for discharge to home include [1]:

●Repletion of fluid status, indicated by weight gain and improvement in clinical status

●Ability to meet maintenance fluid needs with oral intake (eg, volume of oral intake equals or surpasses output) (see "Maintenance intravenous fluid therapy in children")

●Follow-up (in person or by phone) is arranged

●Parents/caregivers understand indications to return to medical care

PREVENTION

Vaccines — Administration of rotavirus vaccine is the most effective way to prevent rotavirus gastroenteritis in children (figure 1). (See "Rotavirus vaccines for infants".)

Several norovirus vaccines are in clinical trials [78-81].

General measures

●Handwashing – Handwashing with soap by caregiver and child, especially after diaper changes or contact with vomitus, may decrease the spread of the viruses that cause acute gastroenteritis [82-85]. Commonly used alcohol-based hand sanitizers have little effect on norovirus, the most commonly detected pathogen in children hospitalized for acute gastroenteritis in the United States [86-89]. A meta-analysis, not limited to viral gastroenteritis, suggested that handwashing with soap reduces diarrheal risk by 47 percent [83].

●Diaper changing – Diaper changing areas should be separate from food preparation areas. Diapers should be disposed of directly in the changing area and put in occlusive bags before moving outside the home. A wipe-down fluid for the changing area should be used; a reasonable choice is diluted household bleach prepared in a spray bottle – alcohol solutions have little effect on norovirus.

●Water purification – Disinfection of water obtained from unsafe water sources is an important means of prevention of gastroenteritis [90]. Methods suitable in the home for disinfection include boiling water for 10 minutes or addition of chlorine-containing tablets or solutions. Application of these interventions may be limited by cost or acceptability [91].

Return to child care or school — Resolution of diarrhea and absence of vomiting are the major factors that determine when the child can return to child care, including church nurseries and similar settings, or school. In general, more restrictive exclusion recommendations are associated with decreased risk to other children.

The American Academy of Pediatrics (AAP) Committee on Infectious Diseases provides the following guidance for returning to child care or school [92,93]:

Children with diarrhea may attend child care or school, provided that:

●Stools are contained in the diaper (for infants)

●The child has no accidents using the toilet (for older children)

●Stool frequency is less than two stools greater than the child's normal stool frequency

Children who have had ≥2 episodes of vomiting related to acute gastroenteritis in the previous 24 hours should be excluded until vomiting has resolved.

The National Institute for Health and Care Excellence (NICE) recommends that children should be excluded from child care or school until ≥48 hours after the last episode of diarrhea or vomiting [2,94].

Return to water recreation — Children with diarrhea should avoid swimming and other water-related activities when they have diarrhea [2,6,94-96]. The AAP recommends that children with acute viral gastroenteritis who are not toilet trained avoid swimming for one week after diarrhea resolves [96]. NICE recommends that children should not swim in swimming pools for two weeks after the last episode of diarrhea [2].

Cohorting patients — Cohorting patients refers to grouping patients with a particular type of viral gastroenteritis (eg, rotavirus) or the clinical syndrome of acute gastroenteritis according to hospital room (for multipatient rooms) or according to caregivers in the hospital. We suggest cohorting children admitted to the hospital with acute gastroenteritis to reduce secondary transmission of viral gastroenteritis pathogens [88,89,97,98]; cohorting generally continues until the last child with acute viral gastroenteritis is discharged. Other experts discourage cohorting, even if based on etiology, because of the possibility of coinfection with another pathogen [1,99]. (See "Acute viral gastroenteritis in children in resource-abundant countries: Clinical features and diagnosis", section on 'Etiology'.)

Contact isolation — For most children hospitalized with acute viral gastroenteritis, standard and contact precautions are recommended [1]. For children with suspected viral gastroenteritis, contact precautions are recommended throughout the duration of illness for children who are in diapers or are incontinent [92,100]. For children with suspected norovirus gastroenteritis, contact precautions should be extended until 48 hours after symptoms resolve [93]. (See "Infection prevention: Precautions for preventing transmission of infection", section on 'Standard precautions' and "Infection prevention: Precautions for preventing transmission of infection", section on 'Contact precautions'.)

In the community, preventive measures to reduce contact with infected persons are, at best, partially effective. Asymptomatic infections play an important role in the spread of infection [88,101,102]. Virus excretion at levels below detection by conventional assays is well established for enteric viruses. In addition, virus excretion can begin before symptoms occur and persist after symptoms resolve. This combination of factors often obscures the source of exposure in individual cases or outbreaks.

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: Acute diarrhea in children".)

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 5^th to 6^th 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 10^th to 12^th 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 email these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient education" and the keyword[s] of interest.)

●Basics topics (see "Patient education: Viral gastroenteritis in adults (The Basics)" and "Patient education: Diarrhea in children (The Basics)" and "Patient education: Giving your child over-the-counter medicines (The Basics)" and "Patient education: Rotavirus infection (The Basics)")

●Beyond the Basics topics (see "Patient education: Acute diarrhea in children (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Supportive treatment – Acute viral gastroenteritis usually is self-limited. It is treated with supportive measures (eg, fluid repletion and unrestricted diet). No specific antiviral agents are available for the treatment of acute viral gastroenteritis. (See 'Management' above.)

•Fluid repletion and maintenance – Fluid repletion and replacement of ongoing fluid losses are the goals of therapy for acute viral gastroenteritis, whether the child is managed at home, in the emergency department, or in the hospital. Fluid repletion is based upon the degree of hypovolemia (dehydration) and presence of hyper- or hyponatremia (table 1). Severe hypovolemia requires rapid intravenous isotonic fluid resuscitation. Oral rehydration therapy (ORT) is the preferred first-line treatment for children with mild to moderate hypovolemia. (See "Clinical assessment of hypovolemia (dehydration) in children" and "Treatment of hypovolemia (dehydration) in children in resource-abundant settings" and "Oral rehydration therapy".)

•Diet – We recommend resumption of an age-appropriate diet, as tolerated, as soon as rehydration is complete (Grade 1B). Breastfeeding can continue during diarrhea. Within the age-appropriate diet, complex carbohydrates, lean meats, yogurt, fruits, and vegetables are better tolerated than foods containing high levels of fats and simple sugars. (See 'Diet' above.)

●Symptomatic therapy – Viral gastroenteritis is usually an acute and self-limited disease that does not require pharmacologic therapy.

•Antidiarrheal agents – We suggest not using antidiarrheal agents (eg, antimotility drugs, antisecretory drugs, adsorbents) in the treatment of acute viral gastroenteritis (Grade 2C). Evidence of efficacy is weak and there is potential for serious side effects. (See 'Antidiarrheal agents' above.)

•Antiemetic agents – For the routine management of children with acute viral gastroenteritis who are not dehydrated, we suggest against ondansetron and other antiemetics (Grade 2C).

For children ≥6 months of age with suspected or confirmed viral gastroenteritis, mild to moderate dehydration (table 1), and vomiting that interferes with ORT, we suggest oral ondansetron rather than other antiemetic agents (Grade 2B). Ondansetron is superior to other antiemetics in stopping vomiting facilitating ORT. The typical regimen is a single oral dose of ondansetron 0.15 mg/kg (maximum dose of 8 mg). (See 'Antiemetic agents' above.)

•Probiotics/prebiotics – Although we generally discourage probiotics and prebiotics, we make decisions on a case-by-case basis. The evidence of benefit is inconsistent. (See 'Probiotics and prebiotics' above.)

•Zinc – We suggest not using zinc in the management of acute viral gastroenteritis in children in resource-abundant countries (Grade 2B). (See 'Zinc' above.)

●Criteria for discharge from the medical setting – For children who are admitted to the hospital for intravenous (IV) fluid repletion or cared for in a medical setting (eg, emergency department, office), minimum criteria for discharge to home include (see 'Discharge from the medical setting' above):

•Repletion of fluid status, indicated by weight gain and improvement in clinical status

•Ability to meet maintenance fluid needs with oral intake (eg, volume of oral intake equals or surpasses output) (see "Maintenance intravenous fluid therapy in children")

•Follow-up (in person or by phone) is arranged

•Parents/caregivers understand indications to return to medical care

●Failure to respond or worsening condition – Conditions other than acute viral gastroenteritis must be considered in children who fail to respond to fluid therapy or whose clinical condition worsens despite fluid therapy. (See "Acute viral gastroenteritis in children in resource-abundant countries: Clinical features and diagnosis", section on 'Differential diagnosis' and "Diagnostic approach to diarrhea in children in resource-abundant settings" and "Approach to the infant or child with nausea and vomiting".)

●Prevention – Measures to prevent acute viral gastroenteritis include rotavirus vaccine, handwashing with soap and water, proper diaper disposal, disinfection of water obtained from unsafe water sources, exclusion of symptomatic children from child care or school, cohorting sick children, and contact precautions for hospitalized children. (See 'Prevention' above.)

ACKNOWLEDGMENT — The editorial staff at UpToDate acknowledge David O Matson, MD, PhD, who contributed to an earlier version of this topic review.