Tag: bronchiolitis

Does Your Child Need an RSV Test?

A lot has changed since this Kansas City RSV outbreak back in 2013.
A lot has changed since this Kansas City RSV outbreak back in 2013.

Your toddler has a cough and runny nose and there is a notice that RSV is going around at daycare…

Do you need to rush to your pediatrician?

Does your child need an RSV test?

Like many things, it depends on who you ask.

For example, the folks at your child’s daycare might push for a visit and an RSV test, thinking it will help them keep the virus from spreading to other kids.

It won’t.

Does Your Child Need an RSV Test?

If an RSV test is available, why not do it?

“Our study showed that a simple nasal swab, while less painful for infants than NPA, failed to detect about one third of cases that were RSV positive by nasopharyngeal aspirate.”

Macfarlane et al on RSV testing in bronchiolitis: which nasal sampling method is best?

For one thing, the test isn’t that accurate, especially when done with a nasal swab, the most commonly used method. And while less invasive than a nasopharyngeal aspirate, if done correctly, sticking a nasal swab up your child’s nose, rotating it around a few times, and then getting a sample isn’t exactly something kids enjoy.

Mostly though, since there is no treatment for RSV, what are you going to do with those test results, whether or not they are positive?

Remember, RSV is a very common respiratory virus that can cause a cold, bronchiolitis, or pneumonia. But testing positive for RSV doesn’t mean that your child has bronchiolitis or pneumonia. Those are typically diagnosed clinically, based on the signs and symptoms that your child has, such as wheezing and trouble breathing.

Similarly, testing negative for RSV doesn’t mean that your child doesn’t have bronchiolitis or pneumonia.

“Clinicians should diagnose bronchiolitis and assess disease severity on the basis of history and physical exam.

When clinicians diagnose bronchiolitis on the basis of history and physical examination, radiographic or laboratory studies should not be obtained routinely.”

AAP on the Clinical Practice Guideline: The Diagnosis, Management, and Prevention of Bronchiolitis

Is there ever a role for RSV testing?

RSV testing might be a good idea when an infant has apnea or other uncommon symptoms.

And if a child is getting monthly Synagis injections and has a suspected case of RSV, it is a good idea to confirm that they actually have RSV.

Why?

If they really do, then you can stop getting Synagis injections, as they are unlikely to get RSV again in the same season.

“In the event an infant receiving monthly prophylaxis is hospitalized with bronchiolitis, testing should performed to determine if RSV is the etiologic agent. If a breakthrough RSV infection is determined to be present based on antigen detection or other assay, monthly palivizumab prophylaxis should be discontinued because of the very low likelihood of a second RSV infection in the same year. Apart from this setting, routine virologic testing is not recommended.”

AAP on the Clinical Practice Guideline: The Diagnosis, Management, and Prevention of Bronchiolitis

That’s pretty clear.

The American Academy of Pediatrics guidelines say that routine RSV testing is not recommended.

Need another good reason to avoid routine RSV testing?

Do you know how long kids with RSV shed the virus or can test positive after having an RSV infection?

“People infected with RSV are usually contagious for 3 to 8 days. However, some infants, and people with weakened immune systems, can continue to spread the virus even after they stop showing symptoms, for as long as 4 weeks.”

CDC on RSV Transmission

Apparently, it is a long time, which means that your child might have a new respiratory infection, but still test positive for RSV because they had it a month ago.

You might actually be “diagnosing” an old infection and not the virus that is causing your child’s current symptoms.

Do you still want an RSV test anyway? Talk to your pediatrician.

Did someone order an RSV test, but you are now wondering if it was necessary? Talk to your pediatrician.

Remember that an RSV test won’t change your child’s treatment (breathing treatments and steroids are no longer routinely recommended when infants have RSV), won’t help predict how sick your child might get, and won’t tell you if your child can return to daycare.

What To Know About RSV Tests

You likely won’t be able to avoid RSV season, especially if your kids are in daycare, but you can avoid RSV testing season.

More on RSV Tests

It’s Not Always the Flu When You Get Sick During Cold and Flu Season

We hear a lot about flu season.

It typically starts in late fall, peaks in mid-to-late winter, and can continue through early spring.

Cold and Flu Season Viruses

It’s important to understand that a lot more is going on, and going around, during flu season than just the flu.

That’s why it is likely more appropriate to think of flu season as just a part of the overall cold and flu season that we see during the late fall to early spring.

During cold and flu season, in addition to the multiple strains of the flu, we see diseases caused by:

  • respiratory adenovirus – can cause bronchitis, colds, croup, viral pneumonia, pink eye, and diarrhea
  • Human metapneumovirus (HMPV) – can cause bronchiolitis, colds, and viral pneumonia
  • Human parainfluenza viruses (HPIVs) – can cause bronchiolitis, bronchitis, colds, croup, or viral pneumonia
  • rhinovirus – the classic common cold
  • Respiratory syncytial virus (RSV) – can cause wheezing and bronchiolitis in younger children, but colds in older kids and adults
  • seasonal coronavirus – can cause colds, bronchitis, and viral pneumonia
  • norovirus – diarrhea and vomiting
  • rotavirus – diarrhea and vomiting, was much more common in the pre-vaccine era

That there are so many different respiratory viruses that can cause bronchiolitis, colds, croup, and flu-like illnesses helps explain why some kids get sick so many times during cold and flu season.

It also helps explain why some folks think they might have gotten the flu despite having been vaccinated, especially in a year when the flu vaccine is very effective.

Is It a Cold or the Flu?

So how do you know if you have the flu or one of these flu viruses during cold and flu season?

Signs and symptoms of the flu vs a cold.
Signs and symptoms of the flu vs a cold.

While the symptoms can be similar, flu symptoms are usually more severe and come on more suddenly.

Can’t you just get a flu test?

While rapid flu tests are fast and easy to do, they are likely not as accurate as you think.

“This variation in ability to detect viruses can result in some people who are infected with the flu having a negative rapid test result. (This situation is called a false negative test result.) Despite a negative rapid test result, your health care provider may diagnose you with flu based on your symptoms and their clinical judgment.”

CDC on Diagnosing Flu

If your pediatrician is going to diagnose your child with the flu because of their symptoms, even if they have a negative flu test, then why do the test?

Rapid flu tests are usually invalid if they are positive for A and B, but many folks are told that they have both.
Rapid flu tests are usually invalid if they are positive for A and B, but many folks are told that they have both flu virus strains.

Can you test for all of the other viruses that are going around during cold and flu season?

Tests can be done to detect most cold and flu viruses.
Tests can be done to detect most cold and flu viruses.

Sure.

The real question is should you.

Like the rapid flu test, many pediatricians can do an RSV test in their office. But like many other viruses, there is no treatment for RSV and the American Academy of Pediatrics actually recommends against routine RSV testing. Whether your child’s test is positive or negative, it is not going to change how he or she is treated.

And the other viruses? Not surprisingly, there are respiratory panels that can test for most or all of these viruses. They also usually include flu and RSV.

The problem with these tests is cost. They are not inexpensive, and again, in most cases, the results aren’t going to change how your pediatrician treats your child.

And they all involve sticking a nasal swab far up your child’s nose…

What About Strep?

While strep throat can occur year round, it does seem to be more common in the winter and spring.

And while you can certainly have two different infections at the same time, such as strep throat and the flu, it is important to remember that the rate of strep throat carriers is fairly high. These are kids who regularly test positive for strep, even though they don’t have an active group A strep infection.

During cold and flu season, if kids routinely get a “strep/flu” combo test, it is possible, or even likely, that many of the positive strep tests are simply catching these carriers.

Remember that a cough, runny nose, hoarse voice, and pink eye are not typical symptoms of strep throat and are more commonly caused by cold viruses. Adenovirus is especially notorious for causing a sore throat, fever, pink eye, runny nose, with swollen lymph nodes = pharyngoconjunctival fever.

Kids who are likely to have strep throat usually have a sore throat, with red and swollen tonsils, and may have swollen lymph nodes, fever, stomach pain, and vomiting, but won’t have typical cold symptoms.

Why does it matter?

Viral causes of a sore throat don’t need antibiotics, while a true strep infection does.

And remember that none of the other cold and flu viruses need antibiotics either, unless your child gets worse and develops a secondary bacterial infection.

What to Know About Cold and Flu Season Viruses

Flu isn’t the only virus that is going around during cold and flu season. Many others can cause flu-like illnesses, croup, bronchiolitis, or just a cold.

More on Cold and Flu Season Viruses