Many of us have had it before without knowing it. France has been observing for a year an epidemic of parvovirus B 19 infections, a virus that is mostly harmless but can occasionally give rise to serious complications, and this has recently accelerated, reported Public Health France. “An epidemic of Parvovirus B19 infections is currently affecting France, having started in May 2023 and affecting all age categories and in particular children,” summarized the public health agency in a press release published Monday evening. “Its intensity increased in the last quarter of 2023 and it continues its rise in 2024 with a peak which has not yet been reached in March,” she added.
Parvovirus B 19 is transmitted by the respiratory route. It most often causes infections that are not serious, or even asymptomatic. In children, it causes mild general symptoms and rash starting on the cheeks and mainly spreading to the hands and feet. They may resemble those caused by measles or simply cause red cheeks. In children, this infection is called the “fifth disease” because it occurs after measles, rubella, chickenpox and roseola.
These infections can nevertheless be dangerous for immunocompromised or anemic people (especially children with sickle cell disease), as well as for pregnant women due to the vulnerability of the fetus. Infection with this virus carries a risk of miscarriage and fetal death. Not all pregnant women share the same level of risk since almost half of them are immunized by a previous infection. Studies show that 50 to 80% of adults have already been in contact with this virus.
Before the Covid-19 pandemic, between one and five people died each year from this infection, mainly adults. But since the start of the year, five deaths have been recorded, all of infants and, for four of them, after an infection of their mother during pregnancy. For the fifth death, an 8-month-old baby, there was no comorbidity or immunosuppression. This number is “unusually high”, according to Public Health France. Although it remains “low”, “it should be monitored because it has increased significantly since 2022 in connection with the more active circulation of the virus and affects children more,” notes the agency.
The agency asks health professionals to inform vulnerable people about the risks and the need to avoid any contact with a person affected or suspected of being affected. Easier said than done, in a context where Parvovirus B 19 infection is not subject to specific surveillance in France. This diagnosis must be mentioned “when faced with a case of measles not confirmed by biological tests”. Pregnant women are also advised to consult a specialized service in the event of decreased fetal movements.
This epidemic, also observed in other European countries such as Denmark, Ireland, Norway and the Netherlands, is part of a broader context of an increase in several infections. Public Health France recently reported a rebound in whooping cough cases, and similar observations have been made for measles or meningococcal infections. These upsurges are generally explained as a consequence of health restrictions taken during the Covid crisis in the early 2020s, then their lifting. These measures have in effect reduced people’s exposure to many pathogens, thereby temporarily reducing the opportunity to build immune responses to them.
