Dutch say 14 air passengers from South Africa with Omicron were vaccinated

Dutch health authorities on Thursday said most of the 62 people who tested positive for Covid-19 after arriving on two flights from South Africa last week had been vaccinated, lending weight to a call for pre-flight testing regardless of vaccination status.

In addition, all 14 passengers who were later found to have been infected with the Omicron variant were vaccinated, health officials said on Thursday.

Under rules in place at the time, more than 600 passengers were able to board the KLM airline flights from Johannesburg and Cape Town on Nov. 26 with either proof of vaccination or recent negative Covid-19 test results.

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A spokesman for the health authority for Kennemerland, in which Schiphol airport is situated, said "around 90%" of those that tested positive were vaccinated.

A spokesperson for the Netherlands' Institute for Health (RIVM) confirmed on Thursday that this included all of the passengers with Omicron.

KLM did not keep track of how individual passengers had met their preflight health requirements.

The infection rate among the passengers from South Africa sparked calls from Dutch health authorities for testing to replace vaccination status for flying.

"By a combination of requiring tests before departure ... and retesting five days after arrival, and knowing what happened, you can make flight safer," Jaap van Dissel, RIVM's head of infectious diseases, said in testimony to parliament on Wednesday.

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He also recommended quarantine for travellers from high-risk areas.

The RIVM's advice, not yet adopted by the Dutch government, is that only a PCR test taken 48 hours before arrival in the Netherlands be accepted, and that it be required regardless of vaccination status.

Countries around the world are tightening flight rules after the discovery of Omicron, dubbed a "variant of concern" by the World Health Organisation, due to worries it could resist vaccinations and prolong the pandemic.

The Dutch government has said it is considering the RIVM's recommendations but it wants any decision to be made at the EU level. France, Portugal and Ireland have already adopted similar policies.

Health authorities in Kennemerland also said on Thursday they were releasing more than half of the infected passengers, who had been kept in isolation at a hotel near the airport, after subsequent tests showed they were no longer carrying the virus.

The authorities did not say whether any of the 14 passengers infected with the Omicron variant were released, citing privacy reasons.