Danish mink mutation ‘could have affected vaccine effectiveness’: study

The coronavirus mutation that led Denmark's government to order the cull of the country's 15m mink -- cluster 5 -- showed resistant to both naturally attained antibodies and those generated by the Pfizer vaccine, a new study by Denmark's infectious diseases agency SSI has concluded.

Danish mink mutation 'could have affected vaccine effectiveness': study
A mink farm on Jedingø, Jutland, before the cull. Photo: Asger Ladefoged/Ritzau Scanpix

The study, published last week in the scientific journal Frontiers in Microbiology, goes some way towards excusing the mink cull, which has been seen as the Danish government’s biggest misstep during the pandemic.

“Blood samples have been taken from people who have recovered from covid-19 infection with cluster 5 and we looked at how well their antibodies could neutralize this virus,” Tyra Grove Krause from the SSI, told the Ritzau newswire.

“You can see that cluster 5 is more resistant to these antibodies than the other virus variants that were in circulation at the time. So on that basis, one can say that this raises concerns about whether the same could apply to vaccine antibodies.”

In an independent study, the SSI researchers also found that the Cluster 5 spike changes were associated with a more than threefold decrease in “neutralization titres” in people immunized with the Pfizer vaccine, indicating a lower antibody response.

“Ultimately, the combination of spike changes in the Cluster 5 variant conferred a degree of resistance to neutralizing antibodies in a proportion of convalescent COVID-19 people,” the article concluded.

In a press release issued on Monday, the SSI said that the virus had continued to evolve rapidly in the mink population, an observation also made in the article. 

“Following the Cluster 5 discovery, a mink-associated SARS-CoV-2 variant with six spike protein changes appeared (L5F, ΔH69/V70, Y453F, D614G, N751Y, and C1250F),” the authors wrote.  “Thus, the virus continued to acquire spike protein changes through its passage in mink.” 

Krause said that it had been this continuing evolution which had made the development in mink so worrying.

The SSI does not, however, recommend a total cull, if coronavirus is identified among herds of farm animals, advising that the infection instead be closely monitored, controlled and limited.

Almost all Denmark’s mink were killed during the last months of 2020. In February this year, the Danish Veterinary and Food Administration confirmed that all the country’s mink had been slaughtered.

The parliament has since made it illegal to keep mink in Denmark until 2022.

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Covid face mask rule on flights in Europe set to be eased

The mandatory EU-wide mask requirement for air travel is set to be dropped from Monday, May 16th, but airlines may still require passengers to wear masks on some or all flights

Covid face mask rule on flights in Europe set to be eased

Europe-wide facemask rules on flights are set to be ditched as early as next week in light of new recommendations from health and air safety experts.

The European Union Aviation Safety Agency (EASA) and European Centre for Disease Prevention and Control (ECDC) dropped recommendations for mandatory mask-wearing in airports and during flights in updated Covid-19 safety measures for travel issued on Wednesday, May 11th.

The new rules are expected to be rolled out from Monday, May 16th, but airlines may still continue to require the wearing of masks on some or all of flights. And the updated health safety measures still say that wearing a face mask remains one of the best ways to protect against the transmission of the virus.

The joint EASA/ECDC statement reminded travellers that masks may still be required on flights to destinations in certain countries that still require the wearing of masks on public transport and in transport hubs.

It also recommends that vulnerable passengers should continue to wear a face mask regardless of the rules, ideally an FFP2/N95/KN95 type mask which offers a higher level of protection than a standard surgical mask.

“From next week, face masks will no longer need to be mandatory in air travel in all cases, broadly aligning with the changing requirements of national authorities across Europe for public transport,” EASA executive director Patrick Ky said in the statement. 

“For passengers and air crews, this is a big step forward in the normalisation of air travel. Passengers should however behave responsibly and respect the choices of others around them. And a passenger who is coughing and sneezing should strongly consider wearing a face mask, for the reassurance of those seated nearby.”  

ECDC director Andrea Ammon added: “The development and continuous updates to the Aviation Health Safety Protocol in light of the ongoing Covid-19 pandemic have given travellers and aviation personnel better knowledge of the risks of transmission of SARS-CoV-2 and its variants. 

“While risks do remain, we have seen that non-pharmaceutical interventions and vaccines have allowed our lives to begin to return to normal. 

“While mandatory mask-wearing in all situations is no longer recommended, it is important to be mindful that together with physical distancing and good hand hygiene it is one of the best methods of reducing transmission. 

“The rules and requirements of departure and destination states should be respected and applied consistently, and travel operators should take care to inform passengers of any required measures in a timely manner.”