RSV is in the news
What do you need to know?
You may have heard that children’s hospitals are filling with kids with respiratory issues already this season. One of the many viruses going around is RSV (respiratory syncytial virus), which can cause bronchiolitis.
Bronchiolitis is an infection of the respiratory tract that leads to wheezing and difficulty breathing, most often in infants and children under 2 years of age. It's often called simply "RSV" but not all cases of bronchiolitis are from RSV and RSV doesn’t always cause bronchiolitis.
Most older kids and adults simply have symptoms of the common cold when they get RSV, but they can spread this virus to others who may get seriously ill from it, such as the very young or elderly.
Below I’ll go through causes of bronchiolitis, the kids who are at most risk, symptoms to watch for, testing options, treatments, and prevention measures. I’ll end with when you should have your child seen by a healthcare professional.
Causes of bronchiolitis
Bronchiolitis can be caused by many of the viruses that cause upper respiratory tract infections. RSV, rhinovirus, metapneumovirus, adenovirus, influenza, parainfluenza, and coronavirus are some of the main culprits.
We don’t usually run tests to see which virus is the culprit because it doesn’t change management and the tests can be expensive.
RSV is a common cause, which is why the condition is often simply called RSV.
RSV (respiratory syncytial virus) gets its name because it causes epithelial cells that line our airways to fuse together and form giant cells called syncytia. Syncytia then die and slough off into the airways. The mucus production with RSV is considerable for many people and really plugs the narrow airways of infants.
Most of us have had RSV by the time we're 3 years old. It doesn't always cause the symptoms of bronchiolitis. Sometimes it just looks like a common cold, especially in older kids and adults. This is why it's really important to protect young infants around people who are just a little sick.
Recently I’ve seen accusations that so many kids are getting sick now because of the “lockdowns” and masks. There are many possible reasons why we’re seeing an early and significant season of RSV, but it is unlikely to be due to preventions used during the pandemic. This is a great thread on why we don’t need to be infected with viruses for our immune system to work - click on it to see the whole thread:
Previous infection with RSV does not protect against another infection. People can be infected with RSV multiple times in the same season. This is not the kind of infection that herd immunity helps. At all. You can get and spread it many times.
I tend to lean toward the theory that post-COVID infection immunosuppression and over (but inappropriate) reactions of the immune system can make people at risk for subsequent infections, but this is not yet known to be the cause of this season’s respiratory outbreaks. The latest CDC data indicates that 86% of children have had COVID - in Kansas, the number is 89%. If only a fraction of these people have abnormal immune system function, that’s still a LOT of people at risk for getting and sharing all sorts of infections.
Who's at risk?
Age and underlying conditions matter. Infants under 6 months of age, those who were born prematurely, those with chronic lung disease or certain heart defects, and those with other chronic conditions are at risk for more significant illness with an RSV infection. (Elderly are also at risk, but as a pediatrician, my focus is on the young ones.)
More exposure = more risk. All viral illnesses are more common among those who are around lots of people. The more people, the more likely they'll be exposed to a person sharing germs. If family members have exposures, risk increases because infections may be brought into the home.
Smoke is irritating. Those who are around cigarette smoke are also more at risk because of the chronic airway irritation caused by smoke. Even infants and children who are around people who smoke prior to being with them can get third hand smoke exposure from hair and clothing.
Symptoms of RSV and bronchiolitis
An RSV infection often starts off just like a common cold, with a runny nose or congestion.
In older children and adults it progresses just like a cold. Because it is.
In infants and young children symptoms can progress to make them more significantly sick. Day 3-5 of illness often is the worst but symptoms can last 2-3 weeks.
Symptoms of an RSV infection can include:
Runny nose
Sneezing
Fever
Ear pain and infections
Rapid heavy breathing (more than 60 breaths per minute - always count for a full minute in babies because they can pant or hold their breath, which throws the count off)
Wheezing (tight breathing with a whistling sound)
Crackling sounds in the lungs
Retractions (the skin between ribs suck in during inspiration)
Nasal flaring (where the nostrils widen with breathing)
Belly breathing (the abdomen moves up and down more than usual)
Cough (which can occasionally cause vomiting)
Lots of mucus from the nose and mouth (lots!)
Decreased appetite (which can lead to dehydration, so offer frequent liquid feedings)
Apnea in infants. This means they stop breathing. It is a reason we often admit very young or high risk infants to the hospital when they have RSV.
Testing
Bronchiolitis is a clinical diagnosis, meaning there are no special tests or imaging studies needed.
Sometimes testing is done, so let’s run through the options and when to use them.
Viral testing
There are tests that can be done on mucus from the nose to see which virus is the culprit, but they aren't usually required.
Knowing if it's RSV or another virus doesn't make the symptoms change. We treat symptoms.
Testing can be used for infection control measures when babies are admitted to the hospital, but aren't always necessary.
Tests can be expensive, and unless they change something we'll do, they aren't generally recommended. Why waste your money? (Even if you think insurance will cover it, the money comes from somewhere... we'll all pay more in premiums if we spend more.)
Oxygen levels
It is common to check oxygen levels when kids (and adults) are sick.
Pulse oximeters are an inexpensive tool to help us assess how well a person is compensating when having trouble breathing.
The ones sold for adult use can be used in older children, but they aren’t reliable when used on infants. Physician offices and hospitals have oximeters made for infants.
Chest x-ray
Most infants and children with bronchiolitis do not need a chest x-ray, but they are sometimes used to assess for pneumonia or foreign bodies (such as a swallowed coin) that can cause wheezing.
Blood work
Blood tests are not usually needed to diagnose or treat bronchiolitis but they can help to identify if there's a need for antibiotics due to a bacterial infection. Sometimes we check blood if we're worried about dehydration.
Treatments
The virus must run its course and symptoms can last several weeks, so what can you do to help ease symptoms?
Home treatments
Comfort measures for pain and discomfort
You can use fever reducers if your baby is uncomfortable. These include acetaminophen if your baby is over 2-3 months and ibuprofen or acetaminophen if your baby is over 6 months.
I don't recommend fever reducers before babies get their 2 month vaccines because you can mask symptoms of serious disease. See your physician if your unimmunized child has a fever!
Remember that a fever is the body's immune system at work, so your goal is comfort, not getting rid of the fever.
More on how to recognize if a fever is too high and the scary facts of fever.
Suck out the snot!
Babies with bronchiolitis often seem as if their nose is a faucet. All that mucus interferes with breathing and feeding. They can't blow their nose, but you can suck it out!
I'm not a fan of bulb syringes as a nasal aspirator. I find that they have too narrow of a tip to get an effective seal in the nostril until you force it up so far that it causes trauma in the nose. They also run out of suction power before the mucus is all out, which means you must break the seal, empty it out, and resume. This gives your child a chance to suck back some of the mucus you brought forward. Not to mention some of the really gross photos I've seen of what grows inside those things if they can’t be opened and cleaned!
Here's a review of various nasal aspirator types and brands. Find one that fits your needs and budget and have it on hand for the inevitable runny nose in your little one.
Use one of the aspirators to suction your infant's nose as they need it. It's especially helpful before feeding and before they go to sleep, but think of how often you blow your nose when you're sick. It can be necessary quite often!
Use saline
Saline can help thin out mucus and decrease the swelling of nasal tissues.
It can be used with or without sucking afterward. I talk a bit more about the benefits of saline in How to use nose sprays correctly.
Fluids
Encourage your baby or child to drink fluids frequently. This can be breast milk or formula for infants, or water for infants over 6 months and children.
Many babies tire out drinking, so they need to drink more frequently than normal to get in a decent volume.
If your baby isn't drinking well and looks dehydrated, talk to your physician.
Humidify the air
A cool mist vaporizer or humidifier can help your child breathe easier during the dry months. (If your AC is on, adding water to the air isn’t needed. The AC will pull it out to help cool the area.)
Change the water every day.
Clean the machine per the manufacturer recommendations to prevent it being a source of germs.
Things to avoid
Never use menthol products around infants. They have been shown to increase mucus production and worsen symptoms, especially in children under 2 years.
Don't demand antibiotics. Viruses cannot be cured with antibiotics. Antibiotics carry risks.
Decongestants thicken mucus and can lead to more difficulty breathing, sleep disturbances and irritability. They are not recommended.
Medically prescribed treatments
Historically we have tried many medical treatments when infants present with bronchiolitis, but there is no treatment that makes anyone better faster. The best treatment is prevention.
Treatments that have been tried include breathing treatments with bronchodilators or saline, oral and inhaled steroids, and more.
A single treatment with a bronchodilator (such as albuterol) can be used to see if there's response to decrease wheezing, but should not be continued if there's no benefit.
Steroids have not been shown to help unless there's a history of asthma.
Oxygen is a standard treatment that can help if the oxygen level is low or to ease the work of breathing.
Intravenous (iv) fluids are often required if hydration from feedings is not successful.
Suctioning is a primary treatment in the hospital setting, much like at home.
Prevention
Standard infection control protocols can help avoid spread.
RSV can survive on hard surfaces for up to 6 hours, on rubber gloves for 90 minutes, and on skin for 20 minutes. This prolonged survival highlights the need for hand washing and surface disinfecting as an essential (and cost-effective) way to limit the spread of infection.
The incubation period ranges from 2 to 8 days.
Once infected, the virus for up to 3 weeks in immunocompetent people. Immunocompromised individuals can continue to spread the virus for several months. (With the recent studies showing COVID-19 infections causing immune system dysfunction, I am curious how much this will affect viral shedding in our communities.)
Wash hands frequently or use hand sanitizer. Teach kids to get all parts of their hands clean. Wash hands frequently even when you're not feeling sick... we share germs before we know we have them and we need to protect ourselves from catching new ones!
When you're sick, wear a quality mask when you’re around others! Your mask can help protect the vulnerable. Don’t bring your mild cold to a co-worker or store clerk who has an infant at home.
Have separate towels (or disposable towels) in the bathroom. After brushing your teeth, you don't want to wipe on a towel that was used by someone who's brewing germs!
Don't kiss babies on their face, hands, or feet. The top of the head is best!
Avoid cigarette smoke - even second hand and third hand smoke (on surfaces) can cause airway irritation. This irritation makes it harder to fend off germs, which leads to more infections.
Clean your child's toys often with soap and water, especially if they share toys with others or bring them out of the home. Kids put everything in their mouth!
Run HEPA filters and ventilate the air by opening windows when possible. Although it is not thought that RSV is primarily spread through the air, there are many viruses (and smoke in some areas) that can contribute to illness, so cleaning the air is a good idea.
If your infant is in one of the high risk groups named above, ask their physician if they qualify for RSV prophylaxis with an injection called Synagis (Palivizumab). This injection is given monthly during the RSV season.
Remember that your little cold can cause serious illness in others, so be kind and stay home with significant symptoms and wear a well fitted mask around others if you have any symptoms of a cold and after symptoms resolve for a few weeks.
When should kids be seen?
Infants and children should be seen relatively quickly if the following criteria are met:
Infants under 2 months of age should be assessed by a clinician who is comfortable assessing young infants. These young infants often require hospitalization because of the risk of apnea. As mentioned above, apnea is when they stop breathing and is a risk of very young infants with bronchiolitis.
Respiratory rate over 60 breaths/minute consistently. It's common to breathe faster with a fever, so if you can bring it down and their breathing is less labored, that's okay. They also temporarily breathe faster after eating or crying. Again, if it slows within a few minutes, that's okay. If they consistently breathe this fast, they may tire out. It can also be a sign that they have low oxygen levels and need help.
Dehydration. Signs of dehydration include no tears, thick/pasty or no saliva, or fewer than 3-4 wet diapers in 24 hours.
The color of the child's lips or skin looks blue.
The infant or child is uncomfortable even after pain relievers are given.
Infants under 3 months (or an under-vaccinated child) with a temperature over 100.4F.
If your child simply isn't getting better after several days or if earache develops, make an appointment during regular office hours.