Dutch public health institute RIVM has identified a further 18 cases of the Omicron variant of coronavirus, taking the total known cases in the Netherlands so far to 36.

The first 18 cases were identified in people arriving on two flights from South Africa on November 26, the day on which new regulations were introduced.

In 14 of the new cases, the variant was found in samples taken from people arriving on flights from southern Africa at Schiphol airport or a regional health board centre.

The remaining four cases were also tested in a regional health board centre but have, as yet, no known connection to southern Africa.

Three specialist test labs in the Netherlands have the facilities to detect the new variant and they are currently checking older samples which may contain Omicron, the RIVM said. These four have been found so far.

No cases of Omicron have yet been found via contact tracing, and it has not been isolated in sewage research or pathogen surveillance.

The RIVM says it expects the Omicron variant will be detected in more samples in the next few weeks. ‘Targeted research looking for the Omicron variant also increases the likelihood it will be found more often,’ the agency said.

‘Reports from other countries, including South Africa and the United Kingdom, suggest it is possible that the Omicron variant will supplant the Delta variant, becoming the dominant version in the Netherlands.’