'Strong increase' of newest omicron variants in Amsterdam

The latest omicron variants of the coronavirus appear to be responsible for 7 percent of the infections in Amsterdam. In a random sample, 13 of the 181 analyzed tests contained the so-called BA.4 and BA.5 variant, the Amsterdam UMC and the GGD Amsterdam report. This is still few in an absolute sense, but it is a "strong increase," said Chantal Bleeker-Rovers, professor of infectious diseases at Radboud UMC, on Twitter.

A week ago, one test in the sample contained the BA.4 or BA.5 variant. The National Institute for Public Health and the Environment (RIVM) previously announced that the new variant had appeared in the Netherlands. At the time, the variant did not seem to have spread further in the Netherlands. The other analyzed tests in the samples indicated the BA.2 variant, the omicron variant that is currently dominant in the Netherlands.

According to the World Health Organization (WHO), the variant does not appear to be more pathogenic or contagious than the current omicron variant. The BA.4 and BA.5 variants have been previously identified by the WHO in Germany, Denmark and southern Africa.

Due to the changes in the genetic material of the variants, it is possible that BA.4 and BA.5 can break through the immune system more easily, despite the fact that someone may have been vaccinated or previously infected with the coronavirus. The RIVM is still investigating this.

The figures appeared on the Twitter account of the partnership ARGOS, which stands for Amsterdam Regional Genomic Epidemiology and Outbreak Surveillance. These are positive results from coronavirus tests that were done at the GGD Amsterdam. The GGD region covers Amsterdam, Amstelveen, Uithoorn, Aalsmeer, Diemen and Ouder-Amstel.

Due to the adjusted testing advice, only healthcare employees, vulnerable people or people who need a recovery certificate are currently taking a test at the GGD. The latter group are often people who are unvaccinated or have not received a booster shot. The sample therefore does not say everything about the distribution of the BA.4 and BA.5 variant in Amsterdam. In earlier variants, Amsterdam was often ahead of the rest of the country, and the sample was an indicator for the course of the variant.