RIVM confirms flu epidemic in the Netherlands; Other respiratory viruses circulating

The number of people with the flu has risen to such an extent that it is now officially an epidemic, the RIVM announced. "The flu virus is found in more and more throat and nose samples from people with flu-like complaints," said the national health institute on Wednesday.

Laboratories, hospitals and general practitioners have increasingly encountered the influenza virus in recent weeks, and the GPs said they are also seeing more patients with flu-like symptoms. The RIVM is monitoring the situation together with research institute Nivel and Erasmus MC. Together they run the National Influenza Center.

The institutes are not using the same pre-coronavirus criteria to determine whether there is a flu epidemic. Previously, an epidemic was first named when more than 58 out of 100,000 people went to their GP with complaints reminiscent of the flu, and 10 percent of the samples examined actually contained the flu virus. In the past week, the number of symptomatic people was below the per capita threshold at 52 per 100,000 inhabitants.

However, of the samples examined in the lab, 21 percent contained the flu virus.

"Just like in the winter of 2021/2022, it is now also difficult to determine whether there is a flu epidemic based solely on these figures," the RIVM explained. "The symptoms of flu are very similar to those of Covid-19. Many people with flu-like symptoms are now doing a coronavirus self-test and may go to the doctor less often." Considering all the information, the scientists determined that the word epidemic is appropriate.

In addition to the flu, several other respiratory viruses are also circulating. Even more often than the flu, laboratories encounter the human metapneumovirus, which can cause approximately the same symptoms. This virus can also vary greatly in severity; Just like the flu, it can remain with a cough and fever, but people can also get pneumonia. The human metapneumovirus was present in 23 of 102 samples examined last week. The RS virus and the rhinovirus are also circulating. The coronavirus is also observed, but not as often at the moment. In addition to the SARS-CoV-2 coronavirus, a regular seasonal coronavirus is also circulating.

Nivel called the rising trend in the number of respiratory infections "appropriate for the time of year." What is also striking is that GPs are seeing a relatively large number of children who are ill due to one of the viruses.

It is the second flu epidemic of 2022. The first wave of flu started in March and was over after thirteen weeks. The fact that the previous flu epidemic only started late in the season was most likely because the flu virus barely had a chance to spread in the previous period due to all the measures against the coronavirus.