Bronchiolitis: the epidemic sets in, later than usual

Usually, the outbreak of bronchiolitis occurs in early winter, starting in November or December.

The epidemic was underway in six regions of metropolitan France between March 1 and 7, against four the previous week, and five regions are in the pre-epidemic phase, according to the weekly bulletin of the public health agency France.

The “surveillance indicators” however fell compared to the last week of February, with a drop of 21% in emergency visits, to 1,413 children under two years old, and a decline of 10% in hospitalizations, to 551.

The overwhelming majority (about 9 out of 10) of these little patients were less than one year old.

Bronchiolitis is a common respiratory disease, most commonly caused by the respiratory syncytial virus, which affects 30% of babies under 2 years of age each winter.

Hospital indicators are usually much higher than this year, with around 6,000 emergency room visits and 2,000 hospitalizations during the peak of the epidemic in winter 2018-2019, and around 5,000 and 1,800 respectively for 2019-2020.

That winter, the saturation of emergency and pediatric resuscitation services in Île-de-France even required transfers of children to the provinces.

Public Health France does not explicitly make the link between the more moderate and later epidemic (of this year) and the application of barrier measures due to the Covid-19 epidemic.

“In the current context of the circulation of Sars-CoV-2 in France, monitoring of infant bronchiolitis for the winter season 2020-21” will allow “monitor the impact of the barrier measures currently in force on the transmission of the respiratory syncytial virus, the main cause of bronchiolitis in infants” and “to study the possible contribution of Sars-CoV-2 to the incidence of this pathology“, she emphasizes, however.

On the other hand, on the seasonal flu side, there is always “no circulation of influenza viruses identified”, underlines the health agency.