What Are the Symptoms of RSV in Babies? What to Know About This Contagious Virus

COVID-19 has dominated headlines for months, but there's another respiratory virus that's gaining national attention: respiratory syncytial virus, aka RSV. Adult can get RSV, but it typically hit very young kids the hardest, with an estimated 58,000 children under age five hospitalized with it every year.

While RSV cases are usually low during warmer months, doctors are reporting spikes across the country right now. After seeing a handful of cases in the winter, data from the Centers for Disease Control and Prevention (CDC) now show that there have consistently been more than 2,000 cases of RSV a week in the US in July. During this time in August last year, there were less than 200 cases a week in the country.

RSV disproportionately affects children, and it can be serious in babies. "Infants less than 6 months and especially less than 3 months old are the most susceptible to severe infection," Seuli Bose Brill, MD, a pediatrician and internist at The Ohio State University Wexner Medical Center, tells Health.

If you have a baby, it's understandable that you might be concerned about RSV. Here's how to spot RSV symptoms in babies, and what to do next.

First, what is RSV?

RSV is a common respiratory virus, according to the CDC. It usually causes mild, cold-like symptoms, but the virus can be serious—especially in infants and older adults. However, most people get better within a week or so of catching the virus. RSV is so common that nearly all children in the US will have been infected by the virus by the second birthday, the CDC says.

How do babies get RSV?

RSV can spread to babies (and anyone) the following ways, per the CDC:

• When an infected person coughs or sneezes
• When virus droplets from a cough or sneeze land in your eyes, nose, or mouth
• When you touch a surface that has the virus on it, like a toy or doorknob, and then touch your face before washing your hands
• When you have direct contact with the virus, like being kissed by someone with RSV

Babies can also get RSV when they're around other kids, including when they're at daycare, Danelle Fisher, MD, a pediatrician and chair of pediatrics at Providence Saint John's Health Center in Santa Monica, California, tells Health.

What are RSV symptoms in babies?

People—including babies—usually show symptoms of RSV within four to six days after they're exposed, the CDC says. RSV may not be severe when it first starts but it can become more serious a few days into the illness. Early symptoms include:

• Runny nose
• Decrease in appetite
• Coughing
• Sneezing
• Fever
• Wheezing

"It starts out looking like a bad cold—a heavy runny nose and a tight, wet cough," John Brancato, MD, an emergency medicine physician at Connecticut Children's, tells Health. "Babies can wheeze and have visible signs that they're having difficulty breathing." That can include their ribs showing on the sides when they breathe and the chest or neck sinking in when they breathe, he says.

How to treat RSV in babies

There is no specific treatment for RSV, but the CDC says there are a few things you can do, including managing your baby's fever with over-the-counter fever reducers and pain relievers like acetaminophen or ibuprofen. (You'll need to talk to your baby's pediatrician for dosing advice before administering any meds.) You also want to make sure that your baby is taking in enough fluids, Dr. Brancato says.

"You'll want to monitor your child for respiratory difficulty or distress—their chest really moving in and out when they breathe or wheezing, which is a high-pitched sound," Dr. Fisher says. "Then it's definitely time to call the pediatrician." Trouble eating, drinking, and sleeping should also be a red flag, Dr. Brill says.

Why are some babies hospitalized with RSV?

Each year, an estimated 58,000 children under the age of five in the US are hospitalized due to an RSV infection, according to the CDC. But some babies are at a higher risk than others for developing severe RSV that can lead to hospitalization. Those include:

• Premature babies
• Very young infants, especially those 6 months and younger
• Children younger than 2 years old with chronic lung disease or congenital heart disease
• Children with weakened immune systems
• Children who have neuromuscular disorders, including those who have difficulty swallowing or clearing mucus secretions

"Sometimes babies do need hospitalization if things get really bad," Dr. Brill says. "Some are just more susceptible to more severe infection."

If your baby is at higher risk or symptoms seem serious, and you're worried or unsure of what to do, Dr. Brill says you should definitely call the doctor. "I always tell parents to call if they have any concerns," she says. Your doctor can help determine if a child needs to be hospitalized.