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Many kids spent much of the 2020-2021 school year remote because of the pandemic. This year, although covid-19 is still a risk, many people are vaccinated and children are physically back in most schools.

But as anyone who cares for a child knows, when kids are together, they spread germs. That means that kids are coming down with a number of different bugs.

Unfortunately, most symptoms, “mild or severe, from vomiting and diarrhea to congestion or runny nose, can be found in any cold, the flu and covid-19,” says Claire Boogaard, a pediatrician at Children’s National Hospital in D.C.

Because it’s so hard to distinguish one virus from another in a home setting, “what we’re recommending is that anybody with these symptoms be tested for covid,” says Sean O’Leary, a professor of pediatrics at the University of Colorado School of Medicine and an infectious-disease specialist at Children’s Hospital Colorado. Some schools even require it.

While you should never send a kid to school sick with anything contagious, it’s especially important to keep your child home until you know they don’t have covid-19. Anyone exposed should get a polymerase chain reaction test three to five days after exposure, says Syeda Amna Husain, a pediatrician based in New Jersey and spokesperson for the American Academy of Pediatrics.

In general, “it’s been a remarkable respiratory [virus] season,” O’Leary says. Last winter, with many people hunkered down at home, there was little circulation of respiratory viruses such as the flu and RSV (respiratory syncytial virus, which typically spreads in winter and can be dangerous for very young children and for older people). But last summer, there was a significant out-of-season RSV spike, along with infections from the delta variant of the coronavirus.

Traits of various bugs

It’s important to reiterate that because covid-19 shares symptoms with a long list of other illnesses, anyone with symptoms should be tested to rule out covid-19. But there are some traits of various bugs that you can use to try to distinguish one virus from another.

Pre-pandemic, many pediatricians would have said it’s not really important to know which pathogen a kid has, unless they are very sick, Boogaard says. Generally, home treatment for most circulating viruses is the same: rest, hydration, and alleviating fever and discomfort. If it’s flu season and a pediatrician realizes early on that a kid has the flu, they could prescribe the antiviral Tamiflu, which may help people recover faster if given early enough, Husain says.

Here are some of the things you’ll typically see with respiratory viruses spreading right now:

Covid-19: The one symptom that’s far more common with covid-19 than with other respiratory viruses is the loss of taste and smell, O’Leary says. Other viruses can affect these senses, but right now, most pediatricians will consider that symptom a pretty telltale sign of a covid-19 case — and it may be the only one that shows up in kids that are otherwise asymptomatic.

Generally, symptomatic covid-19 cases come on gradually, over a period of a few days, but there may then be a sudden escalation of symptoms. Some other common symptoms include fever and cough. Gastrointestinal symptoms such as diarrhea, nausea and vomiting sometimes occur. Some kids may experience trouble breathing — a sign that should prompt a call to the pediatrician or in serious cases a trip to the ER. Symptoms can last for several weeks.

Respiratory syncytial virus: RSV tends to start mild, but it can escalate suddenly. In pediatric cases, the biggest concerns are for kids under 6 months, or those under 2 years of age with lung or heart disease. (In older children, RSV infections usually cause a cold-like illness.) Fevers are common, as are coughs, sore throats, runny noses and sneezing. Pediatricians can generally identify an RSV cough from down the hall, O’Leary says — and can quickly diagnose the virus with a test if needed.

Influenza: The flu can be severe for children, and it’s important to get flu shots now that flu season has started. Boogaard says the flu is often characterized by its abrupt onset: Symptoms tend to appear much more quickly than with other respiratory diseases. Sore throats, fevers, fatigue, coughs, headaches and body aches are all common symptoms, and gastrointestinal symptoms also sometimes occur.

Colds: Colds are caused by many different viruses, including other coronaviruses and rhinoviruses, Boogaard says. Because of this, time of onset and typical symptoms vary, she says. But symptoms typically peak after about three to five days. Most kids are better within seven to 10 days, although a cough may linger for a couple of weeks.

Allergies: Allergies can cause a number of symptoms seen with respiratory viruses, including runny nose, congestion, sneezing and watery eyes. But if your child develops a fever, or is on allergy medication but develops new symptoms, they should be checked out, Boogaard says.

Treatment, emergency signs

In most cases, kids can be treated at home for a respiratory virus, Husain says. Rest is essential, and hydration is important, too. Let them drink what they want — warmer fluids such as soups may be helpful, she says. Saline drops can help with cough or congestion.

It’s fine to give kids medication to reduce fever, such as children’s acetaminophen or ibuprofen, Husain says. But doctors don’t recommend any cough medicines for kids 6 and under, since these can cause changes in heart rate and pose a serious risk.

It’s always a good idea to get in touch with your pediatrician when your child is sick, Husain says, so they can give you some guidance on red flags to look out for.

Some emergency signs include the inability to get water down or stay hydrated. Young kids should have three to five wet diapers, kids should be able to make tears, and their tongues should not look dry. If kids appear to be having trouble breathing, they should be seen by a pediatrician — or at the hospital if it’s clear they are struggling. Signs of breathing trouble include wheezing or seeing their ribs or chest working hard to get air in. If it’s hard to wake kids up, beyond normal tiredness, or to keep them awake, that lethargy is also an emergency sign, Boogaard says.

If your child does test positive for the coronavirus that causes covid-19, you’ll want to provide the same supportive care at home. Doing so will be much easier if you are vaccinated, Boogaard says. As much as you can, try to isolate a sick person and to wear masks while interacting with them, she says.

Returning to school

Many schools have policies in place that determine when kids can return after testing positive for the coronavirus or being exposed to the virus. Because of these policies, kids may also need a negative coronavirus test and a pediatrician’s note to return after having any symptoms.

For other bugs, you should make sure kids have been fever-free for 24 hours without medication before taking them back to class. If they have been vomiting or having diarrhea, that should also be resolved before they return.

A cough can last for two weeks after a cold, although it may last longer in kids with allergies or asthma. Kids can generally go back to school with that lingering cough — just get a note from their pediatrician if you need one.

Getting your child vaccinated against the flu and covid-19 if they are eligible will make navigating this confusing time easier, says Boogaard, who is also the medical director of the Covid-19 Vaccine Program at Children’s National Hospital. And if your child is not caught up on their other vaccinations such as those for measles because of the pandemic, it’s important to do that as soon as possible. “A lot of those diseases are more severe in kids than covid,” O’Leary says.

 Copyright 2021, Consumer Reports Inc.

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