The Omicron vaccine race is on: Researchers at Moderna, BioNTech, Johnson & Johnson and AstraZeneca are racing to test the efficacy of their vaccines against Omicron, reports the Financial Times. The number of mutations in the virus’ spike protein means existing vaccines are less likely to recognise it, putting previously vaccinated or infected individuals at risk. Because of their structure, mRNA vaccines should be the easiest to adapt to the new variant and to scale up, experts said. Shares in mRNA vaccine companies rose on Friday as news of the new variant spread, with Moderna jumping 21%, BioNTech jumping 17% and Pfizer rising 7%. Experts have noted that antivirals will likely be key should vaccines prove ineffective against the new strain as their efficacy is not affected by mutations in the spike protein, though drugmakers have yet to test them against Omicron.

The UK brings back mandatory face masks + post-travel isolation measures to stop the spread of Omicron: Visitors to the UK will now be required to take a PCR within two days of arriving and self-isolate until they receive a negative result, the UK government announced yesterday. Contacts of suspected Omicron cases — even those who are vaccinated — will have to isolate for 10 days. Face mask requirements will be reintroduced in shops and on public transport but not in restaurants or pubs. So far, the UK has detected two cases of Omicron linked to travel to southern Africa. The UK relaxed travel restrictions less than a week ago after its removed quarantine requirements for travelers who have taken Sinovac, Sinopharm and India’s Covaxin.

Omicron is already sidelining possible progress: The World Trade Organization's biennial ministerial conference has been postponed after Switzerland tightened travel restrictions amidst the spread of the variant, according to a statement. The irony is that one of the key topics to be discussed in meetings was how to improve the availability of vaccines in the developing world, the FT reported. The conference was meant to run from 30 November- 3 December and a new date has yet to be set.

Now imagine how bad things would be right now if China had tried to “coexist” with covid-19: China could see over 600k covid-19 cases daily if it were to abandon its “Covid Zero” strategy in favor of reopening its borders and loosening its restrictions, according to a study by the Chinese Center for Disease Control and Prevention. Critically, this study was conducted and published pre-Omicron. Under a US-style reopening, which would see China fully reopen its borders and do away with strict curbs like quarantines and lockdowns, the study forecasts severe cases would surge to nearly double the peak of the initial outbreak in early 2020. This would have “a devastating impact on the medical system of China and cause a great disaster within the nation,” the researchers wrote in the study. China has been facing pressure from analysts and economists to open its borders to avoid an economic crisis for months, but has so far only considered partially opening its borders with financial hub Hong Kong.

Meanwhile, back in regular covid-19 land: Merck’s antiviral molnupiravir was shown to be less effective than previously reported, reducing risk of infection by 30% not 50%, the Financial Times noted. A full analysis of the company’s trial results showed that the oral pill, previously promised to reduce relative risk by 50%, is less effective than preliminary data from initial trials on a small sample of patients indicated. Merck’s shares lost 4% in New York on Friday. Molnupiravir was approved in the UK earlier this month and is still under review in Europe.