RS virus (RSV): Symptoms and therapy

Brief overview

  • What is the RS virus? The respiratory syncytial virus (RSV) is the causative agent of seasonal, acute respiratory infections that particularly affect young children.
  • Symptoms: runny nose, dry cough, sneezing, sore throat; if the lower respiratory tract is involved: fever, accelerated breathing, rales when breathing, wheezing, cough with sputum, dry, cold and pale to bluish skin, sunken fontanel (children under 18 months)
  • Adults: In healthy adults, usually mild or asymptomatic course. Older adults and chronically ill people can become more seriously ill.
  • Course of the disease and prognosis: In children, there are sometimes severe courses with involvement of the lower respiratory tract (bronchiolitis), a fatal course is possible; in adults, an RSV infection is usually uncomplicated.
  • Treatment: No causative therapy possible; symptomatic treatment: hydration, nasal rinsing, decongestant nasal sprays, antipyretic medication, bronchodilators, home remedies, ventilation if necessary
  • Diagnosis: Medical history, physical examination including lung examination, detection of the pathogen (smear test)
  • Prevention: Hygiene measures (washing hands, sneezing and coughing in the crook of the arm, regular and thorough cleaning of children’s toys), passive vaccination for children at risk, active vaccination for people aged 60 and over and pregnant women

RS virus (RSV): Description

The RS virus (RSV, respiratory syncytial virus) is a pathogen that causes acute respiratory diseases. Infants – especially premature babies – and young children are most frequently affected. RSV disease can cause severe respiratory infections in them. Across Europe, around 50 out of every 1,000 children fall ill with RSV in their first year of life, five of them seriously. In rare cases, the disease is fatal in babies and toddlers.

In principle, however, RSV can lead to upper and lower respiratory tract disease at any age. Adults are particularly at risk of becoming seriously ill with the RS virus if they are older than 60 or chronically ill.

What does RSV do in the body?

The RS virus consists of a protein coat (protein envelope) and the genetic information enclosed in it (in the form of RNA). It multiplies in the superficial cells of the mucous membranes that line the airways (epithelial cells). A special protein is anchored in the viral envelope: the fusion (F) protein. It causes the infected mucosal cells to fuse (syncytia formation). These syncytia and the migrating defense cells of the immune system damage the mucous membranes – the cells die and then obstruct the airways.

There are two subgroups of RS viruses: RSV-A and RSV-B. They normally circulate simultaneously, with RSV-A usually predominant.

RSV in babies and small children

In principle, people of any age can become ill from the RS virus. However, young children are particularly frequently affected. The reason for this is that there is no complete nest protection for RS viruses. This means that babies in the first few months of life are not or not sufficiently protected against an RSV infection by maternal antibodies. This particularly affects premature babies – they generally have too few antibodies against the viruses.

An infection with the RS virus is also the most common reason why infants and young children have to be treated in hospital for a respiratory illness. RSV disease can be particularly severe in premature babies and other infants. In premature babies with lung damage and children with heart defects, RSV infection is even fatal in one in 100 cases.

Girls and boys are equally affected by RS infection. However, severe RSV-related illnesses associated with hospitalization occur twice as often in boys as in girls.

RSV during pregnancy

For healthy expectant mothers, an RSV infection usually poses no danger. It usually remains a harmless respiratory infection. Some pregnant women may not even notice that they have an infection.

RS virus (RSV): Symptoms

RSV infections can manifest themselves in different ways. Depending on the age and previous illness of the patient, an infection with RS viruses can develop into either a harmless respiratory infection or – especially in children – a serious, sometimes life-threatening illness.

Sometimes those affected – especially healthy adults – have no symptoms at all. In medical terms, this is referred to as an asymptomatic or clinically silent RSV infection.

Signs of RSV

The first signs of RSV infection are cold-like symptoms. Those affected initially develop harmless symptoms of the upper respiratory tract (mouth, nose, throat) such as a cold, dry cough or sore throat.

Symptoms in babies and small children

The infection can spread to the lower respiratory tract (lungs and bronchi) within 1 to 3 days, particularly in newborns, infants and other high-risk patients. The small branches of the bronchial tree are particularly affected; doctors refer to this as RSV bronchiolitis.

You can find out more about this topic in the article Bronchiolitis.

  • fever
  • Accelerated breathing
  • audible rales and wheezing (whistling noise) when breathing
  • Cough with sputum
  • Difficult breathing with use of auxiliary breathing muscles (support of the arms, retraction of the skin on the chest)
  • shortness of breath
  • Dry, cold and pale skin
  • Blue coloration of the skin and/or mucous membranes (cyanosis) due to lack of oxygen
  • sunken fontanel in children under 18 months of age
  • In around five percent of cases, affected children develop a cough that sounds similar to whooping cough.

In addition, there are general signs of illness such as weakness, feeling ill, lack of appetite and refusal to drink. Problems with eating and drinking sometimes lead to gastrointestinal complaints such as reflux, vomiting, abdominal pain and diarrhea.

A rash on the skin is not typical of RSV infections, unlike other viral diseases in children.

The symptoms of an RSV infection can worsen considerably within a few hours. In premature babies, respiratory arrest (apnea) can occur repeatedly.

RS virus (RSV): Adults

The reason for this is that the immune system functions well in healthy people. It successfully fights the RS viruses and thus prevents them from spreading to the lower respiratory tract.

Severe cases of RSV disease occur mainly in older people aged 60 and over. Adults with heart or lung disease and people with a weakened immune system, transplanted organs or severe blood disorders are particularly at risk.

RSV infections are equally common in women and men. In contrast to children, where boys are often more severely ill, there are no gender differences in the severity of the disease in adults. The same applies to the treatment of RS virus infections in adults: It does not differ from treatment in children.

RS virus (RSV): course of the disease and prognosis

Severe cases mainly affect small children. Premature babies in particular have a high risk of contracting a severe RSV infection in the first six months of life. How good the chances of recovery are and how long babies with a severe RS virus infection have to stay in hospital always depends on the severity of the disease and the general condition of the child.

In rare cases, severe RSV-related respiratory disease in children under two years of age is fatal. Evaluations of several studies show that the disease ends in death in around five percent of children with congenital heart defects and in around four percent of all children with bronchopulmonary dysplasia (BPD). The risk of premature babies dying from the RS virus is around one percent.

Risk factors for a severe course of the disease

The risk of a severe RS virus infection is particularly high for

  • premature babies
  • Children with chronic lung diseases, e.g. bronchopulmonary dysplasia, cystic fibrosis, congenital respiratory anomalies
  • Children with neurological and muscular diseases that restrict lung ventilation
  • People with severe immunodeficiencies
  • immunosuppressive therapy (therapy that suppresses the immune system, e.g. after an organ transplant)
  • Chromosomal abnormalities (such as trisomy 21 = “Down syndrome”)

Other risk factors for a severe RSV disease are

  • Age under six months
  • multiple birth
  • Male gender
  • Siblings in infancy
  • Attendance at a community facility (daycare center, nursery)
  • Smoking household
  • Malnutrition
  • Cases of atopic diseases (such as hay fever, neurodermatitis) or asthma in the family
  • Cramped domestic conditions

When to see a doctor or go to hospital?

Parents should consult a doctor as soon as the child’s symptoms go beyond those of a harmless cold. This is the case, for example, if there is a fever or changes in breathing (rapid breathing, distended nostrils, breathing noises). Bluish discolored skin or lips are also a warning sign. Also pay attention to your child’s eating and drinking habits.

In older children and adults, caution is advised if high fever or breathing difficulties occur after an initially harmless infection. These can be signs of an RS-related infection of the lower respiratory tract.

RS virus: re-infection possible

A past infection offers no long-term protection against the RS virus. A new infection (reinfection) is possible at any age. This lack of immunity is due to the fact that the body hardly forms any antibodies against the RS virus. Reinfections are therefore common – especially in adults with regular contact with small children.

In children, reinfection is often less severe than the initial infection. In adults, reinfection with the RS virus often manifests itself without any symptoms or only as an uncomplicated upper respiratory tract infection. A more pronounced clinical picture with flu-like symptoms is mainly observed in adults with close contact to infected infants.

RS virus: complications and late effects

Complications of an RSV infection occur particularly in premature babies, infants, young children and adults at risk.

There is often a co-infection with other viruses that also affect the respiratory tract. An additional infection with bacteria, on the other hand, is rather rare with an RSV infection.

Pneumonia caused by RSV is another possible complication. People whose immune system is weakened due to illness or therapy are particularly at risk.

An existing asthma condition or other pre-existing illness (such as heart disease) can be exacerbated by an acute RSV infection. On the other hand, the infection can also lead to persistent hypersensitivity (hyperresponsiveness) of the respiratory tract, possibly resulting in early childhood asthma.

In addition, infection with the RS virus is associated with neurological late effects in previously infected children: laboratory experiments with mice have shown that the viruses can enter the brain during infection. One month after an infection, the animals showed neurological abnormalities such as seizures, perceptual and coordination disorders. Learning impairments also occurred.

The spread of RS viruses from the respiratory tract to the central nervous system can be prevented by RSV vaccination.

RS virus (RSV): Treatment

General measures

Adequate fluid intake is helpful to facilitate breathing. This liquefies the mucus in the airways and makes it easier to cough up.

For better nasal breathing, experts recommend nasal rinses or saline nasal drops. A nasal douche with saline solution thoroughly rinses the nasal cavity and removes germs, mucus and other secretions. Nasal drops with saline also keep the nasal cavity clear.

Home remedies

Simple household remedies can also help to alleviate the symptoms:

  • Raise the upper body: Breathing is easier if the upper body is positioned higher than the rest of the body, for example with the help of a pillow.
  • Inhalations: Inhalation helps to relieve symptoms such as coughs and colds. The simplest method involves holding your head over a pot of hot water and breathing in the rising steam. However, this is not recommended for babies and small children – to be on the safe side, only an inhaler should be used for inhalation. Seek advice from your doctor or pharmacy!

Home remedies have their limits. If the symptoms persist over a longer period of time and do not improve or even get worse despite treatment, you should always consult a doctor.

Medication for RSV

If you have a high temperature, your doctor may prescribe antipyretics such as paracetamol or ibuprofen.

A decongestant nasal spray can make breathing easier if you have a severe cold.

Bronchodilators such as salbutamol widen the airways and make breathing easier. They are inhaled and thus reach their destination directly. In severe cases, adrenaline may be administered via the inhaler to dilate the bronchial tubes. It also has an anti-inflammatory effect.

Antibiotics are not effective against the RS virus, as they only help against bacteria and not viruses. They are only prescribed if a bacterial infection (secondary infection) is present in addition to the RS virus infection.

Until a few years ago, severe infection with the RS virus in children was treated with the antiviral drug (antiviral agent) ribavirin. However, studies have shown that it is not effective.

Ventilation

If the oxygen level in the blood drops dangerously, ventilation is necessary. At the doctor’s or hospital, for example, those affected are given oxygen via a breathing mask. Ventilation via a so-called CPAP mask (continuous positive airway pressure) or a tube may also be necessary. The latter is a flexible “tube” that is inserted into the airways and connected to a ventilator.

If an infection with the RS virus leads to respiratory arrest (apnea) in infants, the children must be monitored as inpatients.

RS virus (RSV): Transmission

The RS virus is considered highly infectious. Infection with RSV usually occurs from person to person. However, it is also possible to become infected via contaminated objects or surfaces.

Infection with the RS virus

However, infection is also possible via contaminated hands, objects or surfaces. RSV survives on hands for around 20 minutes, on paper towels or cotton clothing for 45 minutes and on disposable gloves or examination devices such as a stethoscope for several hours.

People infected with RSV can transmit the virus to others just one day after infection – even before they have symptoms themselves. They then remain infectious for three to eight days. Premature babies, newborns and people with severely weakened immune systems sometimes excrete the virus for several weeks and can therefore be infectious to others for a long time.

Incubation period for RSV

The time between infection and the outbreak of an infectious disease is called the incubation period. In the case of the RS virus, it is two to eight days. On average, infected people develop the first signs of illness five days after infection.

RS virus (RSV): Diagnosis

Medical history

First, the doctor takes a medical history (anamnesis). To do this, he will ask about the symptoms and how long they have been present. He will ask you the following questions, among others:

  • How long have the symptoms been present?
  • Does your child have a fever?
  • Has your child had difficulty breathing since becoming ill?
  • Is your child drinking and eating enough?
  • Does your child suffer from an underlying illness, for example a heart defect or cystic fibrosis?

Physical examination

The doctor will then examine your child thoroughly. He will shine a light into the mouth and ears to detect any redness in the throat or ears. He will feel the lymph nodes in the neck for possible enlargement and listen to the lungs with a stethoscope.

RSV bronchiolitis can be heard in the stethoscope as crackling and wheezing.

The doctor will also check whether the fingernails or lips are bluish in color (cyanosis) – a sign of too little oxygen in the blood (hypoxemia).

Pathogen detection

Blood tests that detect antibodies against RS viruses are not usually carried out in the case of an acute RSV infection. The reason for this is that only a few antibodies are produced in RSV-related illnesses. A single blood test therefore does not provide a meaningful result. Repeated antibody tests (at intervals of two to four weeks) are helpful to confirm an RSV infection retrospectively. However, this procedure is usually only used in the context of studies.

RS virus (RSV): Prevention

The most important measure to protect yourself from RSV is hygiene. However, as RS viruses are highly contagious, infection cannot be ruled out.

RSV vaccinations offer good protection against infection and a severe course of the disease. Doctors differentiate between passive vaccinations for children at risk and active vaccinations for adults.

Hygiene

In order to protect yourself in the best possible way within the family and in public life, you should adhere to appropriate hygiene rules. This can counteract the spread of the pathogen:

  • Make sure you wash your hands regularly and properly.
  • Sneeze and cough into the crook of your elbow and not into your hands.
  • People with the disease should not attend communal facilities (daycare centers, schools, etc.).
  • Refrain from smoking – especially around children.

Breastfeeding is also beneficial for infants: Breastfed children are less likely to suffer from respiratory diseases than bottle-fed children.

Vaccination

A passive vaccination against the RS virus is available for children with risk factors. It contains artificially produced, so-called monoclonal antibodies against the RS virus and is injected into a muscle once a month during the RSV season. A total of five vaccine doses are planned, which are administered at four-week intervals from October/November. Ideally, immunization should always take place on the same day of the week.

Passive RSV vaccination is recommended for the following children:

  • Children born before or during the 35th week of pregnancy who are younger than six months at the start of the RSV season.
  • Children under two years of age with congenital heart defects
  • Children under two years of age who have been treated for bronchopulmonary dysplasia (BPD) in the last few months.

On 25.08.2023, the EU Commission granted approval for the first active vaccine for pregnant women. This protects the newborn against the RS virus in the first months of life. It can also be administered to older people aged 60 and over.

You can read more about vaccinations against the respiratory syncytial virus in our article RSV vaccination.