HEALTH OFFICIALS REPORTED last month that some new cases of Covid-19 variants of concern already identified in Ireland had not been linked to international travel.

Minutes from a meeting of the National Public Health Emergency Team on 4 March state that “complex” contact tracing of clusters, where unnamed variants of concern were prevalent, found no evidence that some cases were brought into the country from abroad.

All reported cases of the B1351 strain from South Africa, the P1 and P2 strains from Brazil and the B1525 strain from Nigeria had previously been associated with international travel.

The minutes suggest that there has now been a level of community transmission of these variants, which are linked to more severe illness and lower vaccine efficacy.

They also state that the Health Protection Surveillance Centre was continuing to follow-up such cases within clusters where new variants are “probable”.

To date, health officials have reported 32 cases of the B1351, 12 cases of P1, 14 cases of P2 and 15 cases of B1525.

Assistant Professor of Virology at University College Dublin Gerald Barry described the development reported by NPHET last month as “worrying”.

“It suggests that these variants are now circulating in the community,” he told RTÉ’s Saturday with Katie Hannon programme.

“It’s also important to remember that we’re only sequencing a small fraction of the total number of cases [of these variants] in the country every week. So really it probably isn’t even a full reflection on the number of the cases in the country.

“These numbers are probably lower than the actual number of variants in the country at the moment. We don’t really have a full handle on exactly what every case is and where it’s coming from.

“So it is concerning that these are now beginning to spread and we don’t really seem to be able to track where they’re coming from.”

Director of the National Virus Reference Laboratory Cillian De Gascun previously said that public heath experts believe the Brazilian variants of Covid-19 are “likely” to be more transmissible than other strains, although vaccines remain effective against them.

However, studies have shown that the AstraZeneca vaccine is less effective against the South African variant, which is also more transmissible than previous strains.

Information is still being gathered about the Nigerian variant, although it is shown to have similar mutations to the Brazilian and South African variants, as well as the B117 strain which is now dominant in Ireland.