Headache diarrhea fever. Viral Gastroenteritis: Symptoms, Causes, and Treatment of Stomach Flu

31.08.202327.06.2023 by alexxlab

What are the common symptoms of viral gastroenteritis. How is the stomach flu transmitted. What are the most effective treatments for viral gastroenteritis. Who is at higher risk of contracting stomach flu. How long do symptoms of viral gastroenteritis typically last.

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Understanding Viral Gastroenteritis: The Stomach Flu Explained

Viral gastroenteritis, commonly known as the stomach flu, is a highly contagious intestinal inflammation caused by various viruses. Despite its name, it’s not related to influenza. This condition affects millions worldwide annually, causing significant discomfort and disruption to daily life.

The most common culprits behind viral gastroenteritis are norovirus and rotavirus, although adenoviruses and astroviruses can also be responsible. These viruses spread rapidly, especially in close-quarter environments such as schools, daycare centers, nursing homes, and cruise ships.

How does viral gastroenteritis spread?

Viral gastroenteritis spreads through multiple routes:

Close contact with infected individuals
Consuming contaminated food or water
Touching contaminated surfaces and then touching your mouth
Sharing utensils or personal items with infected people
Poor hand hygiene, especially among food handlers

The highly contagious nature of these viruses means outbreaks can occur quickly in communal settings, making prevention and proper hygiene crucial.

Recognizing the Symptoms of Stomach Flu

Symptoms of viral gastroenteritis typically appear within 12 to 48 hours after exposure, though some viruses like adenoviruses may have a longer incubation period of 3 to 10 days. The onset of symptoms is often sudden, developing over 1 to 2 hours.

What are the primary symptoms of viral gastroenteritis?

The main symptoms include:

Watery diarrhea (more than 3 times per day)
Nausea and vomiting
Abdominal cramps and pain
Fever or chills
Headache
Muscle aches or joint pain
Loss of appetite
Sweating or clammy skin

It’s important to note that while diarrhea is a common symptom, it usually isn’t bloody. The presence of blood in stool could indicate a more severe infection and requires immediate medical attention.

How long do symptoms of viral gastroenteritis typically last?

The duration of symptoms can vary depending on the specific virus causing the infection. Generally, symptoms last anywhere from 1 to 14 days. For instance, norovirus symptoms typically improve within 1 to 3 days, while other viruses may cause longer-lasting symptoms.

Identifying the Culprits: Common Viruses Causing Gastroenteritis

Several viruses can cause viral gastroenteritis, each with its own characteristics and patterns of infection. Understanding these can help in prevention and management of the illness.

Norovirus: The Leading Cause of Gastroenteritis

Norovirus is the most common cause of viral gastroenteritis worldwide. It’s highly contagious and can affect people of all ages. In the United States, norovirus outbreaks are most common between November and April.

Key facts about norovirus:

Spreads rapidly in crowded spaces
Causes sudden onset of nausea, diarrhea, fever, and body aches
Symptoms typically improve within 1 to 3 days
Responsible for about 21 million cases of acute gastroenteritis in the US annually

Rotavirus: A Major Threat to Young Children

Rotavirus primarily affects infants and young children, although it can spread to adults who come into contact with infected children. It’s usually contracted and transmitted orally.

Important points about rotavirus:

Symptoms appear within 2 days of infection
Can cause severe diarrhea in children, leading to dehydration
Vaccination has significantly reduced its prevalence in many countries

Adenovirus and Astrovirus: Less Common but Significant Causes

While less prevalent than norovirus and rotavirus, adenoviruses and astroviruses can also cause viral gastroenteritis.

Adenoviruses:

Can cause respiratory symptoms alongside gastrointestinal issues
Have a longer incubation period (3 to 10 days)
More common in children under 2 years old

Astroviruses:

Typically cause milder symptoms compared to other gastroenteritis viruses
Most common in young children and the elderly
Can spread through contaminated food and water

Risk Factors: Who’s Most Vulnerable to Viral Gastroenteritis?

While viral gastroenteritis can affect anyone, certain groups are at higher risk of contracting the illness or experiencing more severe symptoms.

Which populations are more susceptible to stomach flu?

Groups at increased risk include:

Young children, especially those under 5 years old
Older adults, particularly those in nursing homes or assisted living facilities
People with weakened immune systems due to medical conditions or treatments
Individuals in group settings like schools, dormitories, or daycare centers
Those who travel to developing countries

What factors can increase the risk of viral gastroenteritis?

Several factors can elevate the risk of contracting or experiencing more severe viral gastroenteritis:

Malnutrition, especially low levels of vitamin A or zinc
Recent antibiotic or antacid use
Engaging in anal intercourse
Frequent exposure to group settings or crowded environments
Poor hygiene practices

Understanding these risk factors can help individuals take appropriate precautions and seek timely medical attention when necessary.

Diagnosis and Treatment: Managing Viral Gastroenteritis

Diagnosing viral gastroenteritis typically involves a clinical assessment of symptoms and, in some cases, laboratory tests to identify the specific virus. Treatment focuses on managing symptoms and preventing complications, particularly dehydration.

How is viral gastroenteritis diagnosed?

Diagnosis usually involves:

Physical examination and symptom evaluation
Review of medical history
In some cases, stool sample analysis to identify the virus
Blood tests to check for signs of dehydration or electrolyte imbalances

What are the primary treatment approaches for stomach flu?

Treatment for viral gastroenteritis typically includes:

Oral rehydration: Consuming fluids and electrolytes to prevent dehydration
Rest: Allowing the body to recover and fight off the infection
Gradual reintroduction of food: Starting with bland, easily digestible foods
Over-the-counter medications: To manage symptoms like fever and nausea
In severe cases, intravenous fluids may be necessary to combat dehydration

It’s important to note that antibiotics are not effective against viral infections and are not used in the treatment of viral gastroenteritis.

Prevention Strategies: Reducing the Risk of Viral Gastroenteritis

Given the highly contagious nature of viral gastroenteritis, prevention plays a crucial role in controlling its spread. Implementing proper hygiene practices and taking precautions can significantly reduce the risk of infection.

What are effective ways to prevent stomach flu?

Key prevention strategies include:

Frequent and thorough handwashing, especially before handling food and after using the bathroom
Proper food handling and storage practices
Avoiding close contact with infected individuals
Disinfecting surfaces, especially in shared spaces
Not sharing personal items like utensils or towels
Getting vaccinated against rotavirus (for infants)
Drinking clean, safe water and avoiding potentially contaminated food sources

In group settings like schools or nursing homes, implementing strict hygiene protocols and isolating infected individuals can help prevent outbreaks.

When to Seek Medical Attention: Recognizing Severe Symptoms

While most cases of viral gastroenteritis resolve on their own, certain symptoms warrant immediate medical attention. Recognizing these signs is crucial for preventing serious complications.

What symptoms indicate a need for emergency medical care?

Seek immediate medical attention if you or someone you’re caring for experiences:

Diarrhea lasting more than 2 days without improvement
Blood in the stool
Signs of severe dehydration (dry lips, dizziness, reduced urination)
Inability to keep fluids down due to persistent vomiting
High fever (above 102°F or 39°C)
Severe abdominal pain

For infants and young children, additional warning signs include:

Sunken eyes or fontanelle (soft spot on the head)
Lack of tears when crying
Excessive sleepiness or irritability
Significant decrease in wet diapers

Prompt medical attention in these cases can prevent complications and ensure proper treatment, especially for vulnerable populations like young children and the elderly.

The Global Impact: Viral Gastroenteritis as a Public Health Concern

Viral gastroenteritis is not just an individual health issue; it has significant implications for public health worldwide. Understanding its global impact can help in developing effective strategies for prevention and control.

How does viral gastroenteritis affect global health?

The impact of viral gastroenteritis on global health is substantial:

It’s a leading cause of morbidity and mortality in children, especially in developing countries
Norovirus alone causes an estimated 685 million cases worldwide annually
Rotavirus is responsible for approximately 215,000 child deaths each year globally
Outbreaks can strain healthcare systems and lead to significant economic losses
It contributes to malnutrition in areas with repeated infections and limited resources

The global burden of viral gastroenteritis highlights the need for improved sanitation, access to clean water, and vaccination programs in many parts of the world.

What are the economic implications of viral gastroenteritis?

The economic impact of viral gastroenteritis is considerable:

Lost productivity due to illness and absenteeism
Healthcare costs associated with treatment and hospitalization
Economic losses in the food service and tourism industries due to outbreaks
Costs associated with outbreak control measures in institutional settings

These economic factors underscore the importance of prevention and effective management strategies at both individual and community levels.

Emerging Research and Future Directions in Viral Gastroenteritis

As our understanding of viral gastroenteritis evolves, researchers continue to explore new avenues for prevention, diagnosis, and treatment. Staying informed about these developments can help in better managing and potentially preventing this common illness.

What are some promising areas of research in viral gastroenteritis?

Current and future research directions include:

Development of new vaccines, particularly for norovirus
Improved diagnostic tools for rapid and accurate virus identification
Understanding the role of the gut microbiome in susceptibility and recovery
Exploring antiviral therapies specific to gastroenteritis-causing viruses
Investigating the long-term effects of repeated viral gastroenteritis infections
Studying the potential for viral mutations and emerging strains

These research efforts aim to enhance our ability to prevent outbreaks, improve treatment outcomes, and reduce the global burden of viral gastroenteritis.

How might future developments change the management of stomach flu?

Potential future advancements could include:

More effective and broader-spectrum vaccines
Personalized treatment approaches based on individual risk factors and gut microbiome composition
Advanced preventive measures for high-risk environments like cruise ships and healthcare facilities
Improved global surveillance systems for early detection and control of outbreaks
Novel therapies that can shorten the duration and severity of symptoms

As research progresses, we may see a shift towards more targeted and efficient strategies for managing viral gastroenteritis, potentially reducing its impact on individual and public health.

Viral Gastroenteritis (Stomach Flu): Symptoms and Treatment

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Norovirus

Norovirus is highly contagious and can affect anyone at any age. It spreads through contaminated food, water, and surfaces, or by people who have the virus. Norovirus is common in crowded spaces.

Norovirus is the leading cause of gastroenteritis in the United States and worldwide. Most outbreaks in the United States occur between November and April.

Symptoms include:

nausea
diarrhea
fever
body aches

According to the Centers for Disease Control and Prevention (CDC), most people who become ill with norovirus start to feel better within 1 to 3 days of symptom onset.

Rotavirus

Rotavirus commonly affects infants and young children. Those who contract it can then pass the virus to other children and adults. It’s usually contracted and transmitted via the mouth.

Symptoms typically appear within 2 days of infection and include:

vomiting
loss of appetite
watery diarrhea that lasts anywhere from 3 to 8 days

A rotavirus vaccine was approved for infants in 2006. Early vaccination is recommended to prevent severe rotavirus illnesses in infants and small children.

Adenovirus

The adenovirus affects people of all ages. It can cause several types of illness, including gastroenteritis. The adenovirus can also cause common cold-like symptoms, bronchitis, pneumonia, and pink eye (conjunctivitis).

Children in daycare, especially those under 2 years of age, are more likely to get adenovirus.

Adenovirus is passed through the air via sneezing and coughing, by touching contaminated objects, or by touching the hands of someone with the virus.

Symptoms associated with adenovirus include:

sore throat
pink eye
fever
coughing
runny nose

Most children will feel better within a few days of experiencing adenovirus symptoms. However, symptoms such as pink eye may last longer than a few days.

Astrovirus

Astrovirus is another virus that commonly causes gastroenteritis in children. Symptoms associated with astrovirus include:

diarrhea
headache
mild dehydration
stomach pain

The virus most often affects people in late winter and early spring. It’s transmitted through contact with a person who has the virus or via an infected surface or food.

Symptoms usually appear within 2 to 3 days after initial exposure, and the virus will usually go away within 1 to 4 days.

The main complication of viral gastroenteritis is dehydration, which can be quite severe in babies and young children. Viral gastroenteritis accounts for over 200,000 childhood deaths worldwide per year.

Other complications of viral gastroenteritis include:

nutritional imbalances
body weakness or fatigue
muscle weakness

Dehydration can be life threatening. Call your doctor if you or your child have these symptoms:

diarrhea lasting more than a few days
blood in the stool
confusion or lethargy
dizziness or feeling like you’re going to faint
nausea
dry mouth
an inability to produce tears
no urine for more than 8 hours or urine that is dark yellow or brown
sunken eyes
sunken fontanel on an infant’s head

Dehydration that accompanies viral gastroenteritis can lead to several complications of its own. These include:

brain swelling
coma
hypovolemic shock, a condition that occurs when your body doesn’t have enough fluid or blood
kidney failure
seizures

To prevent complications, get immediate medical attention if you or your child have symptoms of dehydration.

Viral gastroenteritis can spread easily. However, there are some steps you can take to lower your risk of contracting the virus or passing it to others.

Prevention tips

Wash your hands often, especially after using the bathroom and before food preparation. If necessary, use hand sanitizer until you can access soap and water.
Don’t share kitchen utensils, plates, or towels if someone in your household is sick.
Don’t eat raw or undercooked foods.
Wash fruits and vegetables thoroughly.
Take special precautions to avoid contaminated water and food when traveling. Avoid ice cubes and use bottled water whenever possible.
Ask your doctor if you should have your infant vaccinated against rotavirus. There are two vaccines, and they’re generally started around 2 months old.

Was this helpful?

Viral gastroenteritis is an inflammation and irritation of your intestines caused by one of several types of viruses.

Vomiting and diarrhea are among the most common symptoms. You can get viral gastroenteritis from other people or through contaminated foods, drinks, or surfaces.

Generally, viral gastroenteritis symptoms come on suddenly and pass quickly. If diarrhea lasts longer than 48 hours, be sure to follow up with your doctor.

It’s also a good idea to get medical attention if your infant or young child develops diarrhea because it can lead to serious complications due to dehydration.

What Are They and How Long Does a Stomach Flu Last?

Also known as the stomach flu or bug, norovirus often triggers painful gastrointestinal symptoms as well as fever, aches and headaches within days of exposure.
Symptoms may last up to 72 hours after they begin, but this timeline may vary and depends on how you choose to recover at home.
While there isn’t a specific medication for norovirus, frequently washing your hands and cleaning common areas in your home — including the bathroom and kitchen — are essential to keep it from spreading.

Federal health agents are warning Americans that annual cases of norovirus have recently been on a surge here in the United States, per data released by the Centers for Disease Control and Prevention (CDC). Highly viral, norovirus can trigger painful bouts of nausea, vomiting and diarrhea in those who touch contaminated surfaces or share direct contact with someone who is sick, highlighting the need once more for stringent handwashing.

According to CDC figures, more than 200 outbreaks of norovirus — which is sometimes referred to as the stomach flu or stomach bug, though it has no official ties to influenza — have occurred between August 1, 2022 and early January 2023. This is an increase compared to just 172 outbreaks during the same period last year, per the CDC; and positive norovirus cases continued to spike well into the end of February. And it’s likely that total norovirus cases are well underreported given that medical testing is required for a formal diagnosis, as CDC figures place real-time norovirus cases closer to 20 million each year.

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Norovirus tends to surge in the wintertime as more people head indoors, spending time at home fighting off other seasonal illnesses. And because norovirus is spread silently via microscopic virus particles — largely when people accidentally touch an infectious surface and put fingers inside their mouth, or share food or drinks with sick individuals — it can easily rip through whole households at once, explains Ali Alhassani, M.D., pediatrician at Boston Children’s Hospital and head of clinical at Summer Health, a digital pediatric care platform.

“Norovirus is highly contagious and only takes a small amount of virus to infect, [so] it makes sense that all of these factors combined have led to an uptick in cases recently,” Dr. Alhassani tells Good Housekeeping.

You may end up being unlucky enough to come into contact with norovirus by eating or drinking something that’s contaminated, prompting foodborne illness soon after. But one important aspect of preventing this one-off case from affecting loved ones in your household lies in disinfecting high-touch surfaces in your bathroom and in the kitchen, explains Carolyn Forté, the Good Housekeeping Institute‘s Home Care & Cleaning Lab Executive Director.

Read on to learn more about common norovirus warning signs, treating the illness effectively and how you may work to prevent others in your family from getting sick, too.

Common norovirus symptoms

Many associate the stomach flu with gastrointestinal issues that can make everyday life (and even eating!) feel impossible, causing immense pain for days on end. But federal health experts are keen to note that norovirus may also cause other flu-like symptoms, which should clue you into speaking with your doctor to see if norovirus may be to blame. If you’re experiencing headaches or body aches alongside stomach discomfort for days on end, there’s a chance that norovirus is at play.

This year’s norovirus outbreaks have proved consistent with years past, meaning Americans can continue to look for these two particular subsets of symptoms if they’re concerned they’re experiencing a norovirus illness.

“Norovirus symptoms [primarily] include nausea, vomiting, diarrhea, stomach cramping, and sometimes fever, headache and body aches,” Dr. Alhassani explains. “These symptoms are relatively consistent with other strains of years past.”

Diarrhea and vomiting can be particularly concerning, as they may easily lead to dehydration, which can prompt a worsening condition due to things like dizziness and dry mouth. Younger children may not be able to express their thirst at this time, either, and caregivers will see a lack of tears during frustrated cries if this is the case as well.

Since someone can experience a few of the hallmark symptoms of norovirus infections as standalone issues, you may be wondering if your GI discomfort is norovirus-related or something more fleeting. There isn’t a bonafide way to tell, but doctors say that the easiest way to distinguish between norovirus and lesser gastrointestinal distress is how long the issue persists.

“Norovirus symptoms usually appear 12 to 48 hours after exposure, but temporary upset stomach symptoms appear much faster — within a couple of hours,” Dr. Alhassani adds. “However, symptoms from an upset stomach will subside within 24 hours at most, which isn’t the case for norovirus infections.”

To recap, this is the full list of potential norovirus symptoms as noted by CDC officials:

Fever
Headache
Body aches
Stomach pain
Nausea
Vomiting
Diarrhea

It’s crucial to remember that norovirus — which is just one example of enterovirus, a group of viruses that may impact the gastrointestinal tract — may require hands-on medical care and, in some cases, hospitalization if symptoms are severe and left unchecked.

How long does norovirus last?

Unlike other discomforting issues like food sensitivity or poor food quality, norovirus illness doesn’t usually produce immediate symptoms; it may be a few days before the symptoms listed above present in impacted individuals. Dr. Alhassani says most cases of norovirus cause symptoms to become apparent between 12 and 48 hours after exposure.

Not all illnesses caused by norovirus are the same, meaning some individuals may have more severe symptoms based on their own exposure as well as any preexisting health conditions. If you are currently experiencing norovirus sickness, you should expect to feel extremely ill and to experience continuous gastrointestinal issues throughout the day. Feeling continuously nauseous or experiencing chronic diarrhea is expected, for example, until the sickness has run its course.

How does norovirus spread?

Put simply, norovirus can spread through feces, vomit and other bodily excretions — and more often, through small virus particles that remain transmissible on a contaminated surface. CDC officials note that those who are impacted can “shed billions of norovirus particles” that are naked to the eye, and only a relatively small amount of these viral particles can infect another otherwise healthy individual.

People are most contagious when they are experiencing symptoms, as well as during the first few days of recovery when symptoms have largely subsided, according to published research.

Because viral norovirus particles may easily contaminate surfaces — including food that may be placed on sullied surfaces in the kitchen — keeping your hands properly washed if you are sick is crucial. Your family will also need to keep an eye on the rest of your home; both Clorox and Lysol make products that can effectively kill traces of norovirus on surfaces when used according to manufacturer’s directions, our Good Housekeeping Cleaning Lab experts say.

“Food prep and food contact surfaces are important as are most high-touch areas in both the bathroom and the kitchen, including faucet handles, appliance handles, cabinet and drawer pulls, light switches, and shower knobs,” explains Forté. “And most of these products recommend rinsing after using them on food contact surfaces, like countertops and a baby’s high chair tray. Make sure you check the usage directions about food contact surfaces.”

Using a cleaning product versus a disinfectant spray requires different approaches — but whichever product you use at home to keep norovirus from spreading, be sure you thoroughly clean the surfaces first, then keep them wet with the disinfectant for the required time. For example, Purell’s Multi-Surface Disinfectant requires a surface to remain wet with cleaner for 30 seconds to one minute to fully disinfect.

“Follow the usage directions on products by keeping the surface wet for the required time to be sure the product is completely killing germs,” Forté adds.

Lastly, it’s important to note that hand sanitizer doesn’t always work to eliminate norovirus risk, and shouldn’t be substituted for handwashing, according to the CDC.

How to treat norovirus at home

The only way to confirm if you are experiencing a norovirus infection is to seek out medical care from your doctor or a qualified urgent care clinic, where a PCR test will confirm the virus’ presence. There isn’t a particular medication used to treat norovirus alone, but further medical attention may be necessary to treat severe dehydration caused by chronic vomiting and diarrhea.

Staying well hydrated while you are recovering is essential, working in plenty of water and other fortifying beverages to help your body recover, Dr. Alhassani adds. Using over-the-counter products like Tylenol or Advil may ease non-gastrointestinal issues as you recover.

“Eating foods that are easier to digest — think items like crackers, toast, rice, and potatoes, for example — are helpful with GI distress,” he says. “Most importantly, practicing good hand hygiene will help prevent illness and keep other people inside the home from catching it as well.”

How to Completely Disinfect Your Toilet

Zee Krstic

Health Editor

Zee Krstic is a health editor for Good Housekeeping, where he covers health and nutrition news, decodes diet and fitness trends and reviews the best products in the wellness aisle. Prior to joining GH in 2019, Zee fostered a nutrition background as an editor at Cooking Light and is continually developing his grasp of holistic health through collaboration with leading academic experts and clinical care providers. He has written about food and dining for Time, among other publications.

Coronavirus disease 2019 (COVID-19) – Criteria

This section is available free of charge

World Health Organization: Severity of COVID-19[79]World Health Organization. COVID-19 clinical management: living guidance. 2021 [internet publication].
https://www.who.int/publications/i/item/WHO-2019-nCoV-clinical-2021-1

Mild disease

Symptomatic patients who meet the COVID-19 case definitionwithout signs of hypoxia or pneumonia.
Symptoms include fever, cough, fatigue, anorexia, shortness of breath and myalgia. Other non-specific symptoms include sore throat, nasal congestion, headache, diarrhea, nausea/vomiting, and loss of smell/taste. The following additional neurological manifestations have also been reported: dizziness, agitation, weakness, convulsions, or signs of a stroke. Fever or cough may not be as common in children as in adults.
Atypical symptoms (eg, fatigue, decreased alertness, decreased mobility, diarrhoea, loss of appetite, delirium, absence of fever) may occur in the elderly and those with immunosuppression.
Symptoms of physiological adjustments during pregnancy and adverse effects of pregnancy (eg, shortness of breath, fever, gastrointestinal symptoms) or other illnesses (eg, malaria) may overlap with symptoms of COVID-19.

Moderate illness

Adolescents or adults: Clinical signs of pneumonia (fever, cough, shortness of breath, rapid breathing) but no signs of severe pneumonia, including oxygen saturation in room air (SpO₂) ≥ 90%.
Children: Clinical signs of mild pneumonia (eg, cough or difficulty breathing plus rapid breathing and/or retraction of the intercostal spaces) and no signs of severe pneumonia. Rapid breathing is defined as:
- Age <2 months: ≥ 60 bpm
- Age 2-11 months: ≥ 50 bpm
- Age 1-5 years: ≥ 40 bpm 900 03
Diagnosis can be based on clinical findings, but chest imaging can help diagnose and identify or rule out pulmonary complications.

Severe illness

Adolescents or adults: clinical signs of pneumonia (fever, cough, shortness of breath, rapid breathing) plus one of the following:
- Respiratory rate > 30 bpm.
- Severe respiratory distress
- SpO₂ ≤90% when breathing room air.
Children: clinical signs of pneumonia (cough or panting) plus at least 1 of the following: 6 Severe respiratory distress (eg, rapid breathing, snoring , very pronounced retraction of the intercostal spaces)
General warning signs: inability to breastfeed or drink, lethargy or unconsciousness, or convulsions
5 years: ≥40 breaths per minute).

Diagnosis can be made on clinical grounds, but chest imaging can help diagnose and identify or rule out pulmonary complications.

Critical illness

Acute respiratory distress syndrome (ARDS), sepsis, septic shock, acute thrombosis, or multisystem inflammatory syndrome in children.

National Institutes of Health: Clinical Classification of COVID-19[479] National Institutes of Health. Coronavirus disease 2019 (COVID-19) treatment guidelines. 2021 [internet publication].
https://covid19treatmentguidelines.nih.gov

Asymptomatic and subsymptomatic infection