Pregnancy and prevention of infections with parvovirus B19

Parvovirus B19 is a small-sized virus which only infects humans. Transmission occurs via respiratory secretions (coughs, sneezes, spit or nasal mucus) from young children. It is a common, minor illness also known as fifth disease or megalerythema epidemicum. If a pregnant woman not previously immune is infected during pregnancy, there can be implications for the foetus.
In spring 2024, a significant outbreak occurred, but such epidemics are generally rare and tend to follow seasonal patterns, appearing approximately every 2–3 years. As of 2025, the situation has returned to normal, with no epidemic peak reported so far. 

Usually, the illness goes unnoticed (in approximately 50% of adult cases) or causes very vague symptoms (slight fever, headaches). When symptoms do occur, these usually appear in two phases: first, the face is affected, with red cheeks (making you look like you have been slapped on both cheeks), and then the rash spreads to the skin on the limbs and torso. On rare occasions, joint pain can occur. 

A viral infection can lead to fetopathy, which may present as cardiac damage and, notably, anemia, which may be severe. The risk is low and depends on when the infection occurs during pregnancy. Talk to your healthcare professional for more detailed information. The risk is higher if the infection happens during the second trimester. 

​​​​​​Women at risk are those who are exposed to the virus for the first time during pregnancy. The immune status regarding the virus can be evaluated with a blood test (parvovirus serology).
If you come into contact with an infected individual, or if you are displaying clinical signs, talk to your health professional. Follow-up blood tests and/or ultrasounds may be recommended.

Avoid close contact with respiratory secretions from infected individuals.

Wash your hands regularly. As the virus can cause small outbreaks in community venues frequented by children, pay attention to information provided by educational staff.