Respiratory syncytial virus (RSV) is a serious cause of respiratory infection that can affect people of all ages. But it’s most serious in babies.

A baby’s airways aren’t as well-developed, so a baby isn’t able to cough up mucus as well as an older child. In most people, RSV causes cold symptoms, often with a cough.

In babies, RSV can cause a more serious illness called bronchiolitis. Babies with bronchiolitis have wheezing along with their cough.

RSV can lead to other severe infections, including pneumonia. In some cases, babies may need to receive treatment at a hospital.

RSV is a virus, so unfortunately there are no medications that can cure it in order to shorten its course of infection. Here’s what you need to know.

In older children, RSV can cause symptoms similar to that of a cold. But in babies, the virus causes more severe symptoms.

RSV is most commonly transmitted from November to April, when cooler temperatures bring people indoors and when they’re more likely to interact with each other.

RSV tends to follow a timeline of symptoms. Symptoms peak around the 5th day of the illness, but they may start experiencing symptoms earlier or later.

Initial symptoms may not be all that noticeable, such as decreased appetite or a runny nose. More severe symptoms may appear a few days later.

Symptoms a baby may have with RSV include:

  • breathing that’s faster than normal
  • difficulty breathing
  • cough
  • fever
  • irritability
  • lethargy or behaving sluggishly
  • runny nose
  • sneezing
  • using their chest muscles to breathe in a way that appears labored
  • wheezing

Some babies are more vulnerable to the symptoms of RSV. This includes children who were born prematurely, or babies with lung or heart problems.

RSV cases can range from mild cold symptoms to those of severe bronchiolitis. But if you suspect your baby has RSV, it’s important to call your pediatrician or seek emergency medical care.

Symptoms to watch out for include:

  • your baby appears dehydrated, such as sunken fontanels (soft spots) and no tear production when they cry
  • coughing up thick mucus that’s gray, green, or yellow in color making it hard to breathe
  • fever greater than 100.4°F (38°C), rectally obtained, in babies younger than 3 months
  • fever greater than 104.0°F (39.4°C) in a child of any age
  • thick nasal discharge that makes it tough for baby to breathe

Seek immediate medical care if your baby’s fingernails or mouth are blue in color. This indicates your baby isn’t getting enough oxygen and is in severe distress.

In the most severe cases, RSV may require the help of a breathing machine known as a mechanical ventilator. This machine can help to inflate your baby’s lungs until the virus has had time to go away.

Doctors used to (and some still do) routinely treat most cases of RSV with bronchodilators. But this is no longer recommended.

Examples of bronchodilator medications include albuterol, which is under the brand names:

  • ProAir HFA
  • Proventil-HFA
  • Ventolin HFA

These are medications used for people with asthma or COPD to help open up the airways and treat wheezing, but they don’t help the wheezing that comes with RSV bronchiolitis.

If your little one is dehydrated, their doctor may also provide intravenous fluid (IV).

Antibiotics won’t help your baby’s RSV because antibiotics treat bacterial infections. RSV is a viral infection.

If your doctor gives you the OK to treat RSV at home, you’ll likely need a few tools. These will keep your baby’s secretions as thin as possible so they don’t affect their breathing.

A bulb syringe

You can use a bulb syringe to clear thick secretions from your baby’s nose. Get one here.

To use the bulb syringe:

  1. Compress the bulb until the air is out.
  2. Place the tip of the bulb in your baby’s nose and let the air out. This will pull mucus in.
  3. When you remove the bulb, squeeze it onto a cloth or paper towel to clear the bulb.

You should especially use this tool before your baby’s feeding. A clear nose makes it easier for your baby to eat.

This can also be combined with over-the-counter saline drops, which can be placed into each nostril followed right afterward with suctioning.

Cool mist humidifier

A humidifier can introduce moisture into the air, helping to thin your baby’s secretions. You can purchase cool mist humidifiers online or in stores. Make sure to clean and care for the humidifier properly.

Hot water or steam humidifiers could be harmful to your baby because they can cause scalding.

You can also talk to your child’s doctor about treating any fevers with acetaminophen (Tylenol). Your doctor will give you a suggested dose based on your baby’s weight. Do not give your baby aspirin, as this can be dangerous to their health.

Providing fluids, such as breast milk or formula, can be important to preventing dehydration in your baby. You can also ask your doctor if you should give your baby an electrolyte-replacing solution.

Keep your baby in an upright position, which makes it easier for them to breathe. You can keep your baby more upright in a stable and secure car seat or baby seat while they are awake at times during the day.

At night, you can raise your child’s mattress by about 3 inches. You can place an object underneath your baby’s mattress to keep it higher up. Always place your baby on their back to sleep.

Limiting your baby’s exposure to cigarette smoke is also vital to keeping them healthy. Cigarette smoke can make your baby’s symptoms worse.

When an otherwise healthy baby has RSV, they’re typically contagious for three to eight days. The child who is contagious should be kept separate from other siblings or children to prevent transmission.

The disease is spread from direct and indirect contact with an infected person. This could include touching the hand of an infected person after they sneeze or cough, then rubbing your eyes or nose.

The virus can also live on hard surfaces, such as a crib or toys, for several hours.

Babies can make a full recovery from RSV in one to two weeks. Most babies can recover from RSV without having to receive treatment in a hospital setting. But if you think your baby is dehydrated or in moderate to severe distress, seek emergency medical care.

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