Protecting an infant from RSV involves two main strategies: immunization (either before or after birth) and everyday precautions that reduce exposure. RSV season in the United States typically starts in the fall and peaks in winter, and nearly all children catch it by age two. For most, it’s a bad cold. For infants under six months, it can become serious fast. Here’s what actually works to lower that risk.
Immunization: The Most Effective Protection
The single biggest thing you can do is make sure your baby receives nirsevimab, an antibody injection given to infants before or during RSV season. It’s not a vaccine in the traditional sense. Instead of training the immune system to make its own antibodies, it delivers ready-made antibodies that go to work immediately. CDC data from the 2024-2025 season found nirsevimab was 80% effective at preventing RSV-related ICU admissions and 83% effective at preventing acute respiratory failure in infants during their first RSV season.
Timing matters. The CDC recommends the injection during October through March for most of the continental United States. The ideal window is shortly before RSV season begins, typically October or November. Babies born during the season (October 1 through March 31) should receive it within their first week of life, ideally before leaving the hospital.
Maternal RSV Vaccination During Pregnancy
If you’re pregnant, there’s a second option: a maternal RSV vaccine (Abrysvo) given between weeks 32 and 36 of pregnancy. The vaccine prompts your body to produce antibodies that cross the placenta and reach your baby before birth, providing roughly six months of protection, covering the period when infants are most vulnerable.
The CDC recommends this vaccine if you’re 32 to 36 weeks pregnant during September through January in most of the U.S. Your baby does not need both the maternal vaccine and nirsevimab. If you received the vaccine during pregnancy, your newborn typically won’t need the antibody injection unless they’re at higher risk for severe disease. Talk with your OB or pediatrician about which approach fits your timeline.
Breastfeeding Reduces Severity
Breastfeeding won’t prevent RSV infection, but it meaningfully reduces how severe it becomes. In a multicenter study of hospitalized infants with RSV, babies who were exclusively breastfed needed oxygen therapy only 4.3% of the time, compared to 13.5% for those fed exclusively with formula. That’s roughly a fourfold difference in the odds of needing oxygen support. Separate research has found that exclusive breastfeeding for more than four months reduces the risk of hospitalization for lower respiratory infections by about 72% in the first year of life.
Breast milk contains antibodies and immune factors that coat the lining of your baby’s airways. Even partial breastfeeding offers some benefit over none, so if exclusive breastfeeding isn’t possible, a combination still helps.
Everyday Habits That Lower Exposure
RSV spreads through respiratory droplets and contaminated surfaces. The virus survives on hard countertops for up to six hours, on rubber or plastic surfaces for about 90 minutes, and on fabric or paper tissues for 30 to 45 minutes. It can transfer from a contaminated surface to your hands and remain infectious on skin for up to 25 minutes. That means a quick touch of a doorknob or grocery cart followed by touching your baby’s face is a realistic route of infection.
Practical steps that make a real difference:
- Handwashing before handling your baby. Every caregiver, every time. This is the single most effective everyday precaution because the virus travels so easily on hands.
- Limiting close contact with sick people. Anyone with cold symptoms, even mild ones, should stay away from your infant. Adults and older children often carry RSV as a regular cold without realizing it.
- Cleaning high-touch surfaces regularly. Countertops, changing tables, and toys benefit from a simple wipe-down with soap and water or a household disinfectant, especially during RSV season.
- Avoiding crowded indoor spaces. Shopping malls, waiting rooms, and large gatherings during peak season (December through February) increase your baby’s exposure risk. When possible, keep your infant out of these settings during their first winter.
- Keeping older siblings’ germs in check. Daycare-age siblings are the most common source of RSV in a household. Have them wash hands and change clothes when they get home before interacting closely with the baby.
Recognizing RSV Symptoms Early
RSV usually starts looking like a standard cold: runny nose, cough, mild fever, decreased appetite. In most babies, it stays that way. The concern is when it moves into the lower airways, which can happen within a few days of the first symptoms. Babies under six months and premature infants are at the highest risk for this progression.
Watch for these specific signs of respiratory distress:
- Retractions. The skin between or below the ribs visibly pulls inward with each breath. This means your baby is working harder than normal to breathe.
- Nasal flaring. The nostrils widen noticeably with each inhale.
- Fast breathing. Count breaths for a full minute. Anything consistently above 60 breaths per minute in a newborn, or a noticeable jump from their normal rate, is a red flag.
- Grunting or wheezing. A small “ugh” sound at the end of each breath, or a whistling noise, suggests the lower airways are involved.
- Pale or bluish color. Check around the lips, fingernails, and under the eyes. Any blue tint means oxygen levels are dropping and requires emergency care immediately.
- Clammy skin. Skin that feels cool and sweaty at the same time signals the body is under significant stress.
If your baby shows retractions, grunting, or any color changes, don’t wait to see if it improves. Bluish lips or face, or any sense that your baby is struggling to breathe, warrants a call to 911 or an immediate trip to the emergency room.
When Your Baby’s Timing Affects the Plan
The protection strategy that makes sense depends largely on when your baby is born relative to RSV season. A baby born in July or August, for instance, will be a few months old when the season starts and should receive nirsevimab in October or November, right before RSV activity picks up. A baby born in December should get the injection before leaving the hospital.
If you’re due in October or November, the maternal vaccine given a few weeks before delivery can transfer antibodies to your baby in time. If you’re due in the spring or summer, the maternal vaccine is less useful because RSV season will have passed by the time your baby arrives, and the antibodies would wane before the next season starts. In that case, nirsevimab in the fall is the better route.
Your pediatrician can help you map out the timing. The key point is that one form of immune protection, whether from the maternal vaccine or the infant antibody injection, should be in place before your baby’s first RSV season begins.