This web-page is intended for English speaking caregivers and parents in Sweden.

En kvinna och en bebis

What is RSV?

Ett virus

RSV Overview

RSV stands for Respiratory Syncytial Virus. It's a very common virus that can be easily passed from person to person. 

In babies, RSV generally causes mild to moderate cold-like symptoms. But in babies with certain risk factors, it can cause serious lung infections that need to be treated at a hospital. 

When is RSV season?

RSV outbreaks can happen any time of year. They usually happen during colder, wintry months, and last for an average of 5 months. Since RSV seasons can vary by region, it's always best to ask your doctor about when it occurs in your area. 

Every week between October and May, Folkhälsomyndigheten (The Public Health Agency of Sweden) compiles an overview of the number of reported cases of RS virus in each county. At their website you can find the weekly report (although only in Swedish) and follow the current situation in your area. The numbers are based on laboratories' and pediatric clinics' voluntary reports to the authority. It gives a good picture of the virus' spread across Sweden during the season.


North of the equator

Every year, RS viruses appear as epidemics across the globe. In Sweden, we have the spread of RS virus, especially during the cold season. The season can start already in September and last well into the spring. The intensity and length of the RS virus season varies from year to year and local differences across the country are common.

Near the equator

RSV occurs year-round with some increase in the rainy season.

South of the equator

RSV season begins sometime between March and June.

How does RSV spread?

RSV is spread easily through sneezing, coughing, or by touching something that might have the virus on it.

Två händer som rör varandra

Person-to-person contact

Person-to-person contact, such as kissing or sharing cups/ eating utensils.

Två otvättade händer

Unwashed hands

RSV can survive 30 minutes or more on unwashed hands.


Objects or surfaces

RSV can survive up to 6 hours on surfaces such as toys, keyboards, or doorknobs.

What are the symptoms of an RSV infection?

It takes three to six days from being infected with the RS virus to getting symptoms. At first, symptoms of an RSV infection may resemble those of a cold. A milder infection passes in one to two weeks, but those who get a more serious lower respiratory tract infection get a more prolonged illness with difficulty breathing and cough for up to a couple of weeks. Symptoms include:

  • Low-grade fever
  • Dry cough
  • Mild headache
  • Runny nose
  • Sore throat

Most children do not experience serious RSV infections. But for those who do, the RSV infection can spread to the lungs, causing pneumonia or bronchiolitis. Symptoms can include fever, shallow or rapid breathing, coughing, wheezing, decrease in appetite, and a blue colour to the skin. 

If your child is showing more serious symptoms or is considered to be at high risk for serious complications from an RSV infection, do call 1177 (Vårdguiden) for medical information and advice. (1177, Vårdguiden, is Sweden's gathering place for information and services in health and care throughout Sweden).

If your infant is tired and exhausted, has difficulty breathing and/or has a high fever contact a pediatric clinic or a primary care center (vårdcentral). After closing time, contact the nearest emergency department. In case of acute illness call emergency number 112  for ambulance transport.

When should you call a doctor?

While not common, these symptoms may worsen and could indicate a serious RSV infection:

Blåa lungor

Short, shallow, rapid breathing, or difficulty breathing; chest muscles and skin pull inward with each breath.

Ett barn som nyser

Wheezing: you can hear a high-pitched noise when baby is breathing out.




Decrease in appetite.

En hand som vinkar

Irritability or unusual tiredness; bluish colour to the skin.


How are RSV infections treated?

There is no cure for RSV. Antibiotics are only helpful for infections caused by bacteria, not viruses. However, your doctor can recommend ways to make your baby more comfortable and can let you know what signs to watch for that may mean the infection is becoming more serious and may require hospital care. 

Currently, there is no vaccine available to prevent RSV, but there are medicines that might help if your child is at risk for serious RSV infections.