• The University of Hong Kong issues a press release detailing the work of researchers from its Faculty of Medicine, who used lung tissue samples to look at how Omicron infects the respiratory tract. They discovered that Omicron multiplies 70 times faster than the Delta variant in human bronchus, which may explain its rapid transmission. Notably, they found lower levels of Omicron infection in the lungs (versus the original version of SARSCoV-2), which may indicate milder disease; their research is currently under peer review for publication. Source

• The European CDC issues an assessment of the emergence and potential impact of Omicron in the context of ongoing transmission of the Delta variant in the EU/EEA. Overall, 66.8 percent of the region’s population is fully vaccinated, and booster campaigns for adults are accelerating.

The ECDC assesses the probability of Omicron’s further spread in the region as very high. During the week ending on 15 December, an increasing number of Omicron cases were acquired locally, rather than from travel, with a rapid increase of cases anticipated during the next two months. Although Delta is still predominant, Omicron is likely to become dominant within the first two months of 2022 – and even if it causes milder illness than Delta, Omicron’s increased transmissibility will outweigh the benefits of potentially reduced severity. The report calls for “…strong and immediate reductions in contact rates are also required to avoid a high spike in cases caused by the Omicron VOC….even with an immediate acceleration of vaccine roll-out,” and recommending that “…non-pharmaceutical interventions should continue to be implemented by all countries, and given the impending probably dominance of the Omicron VOC, these need to be further strengthened without delay,” warning that without these measures and boosters, levels of transmission “…could rapidly overwhelm EU/EEA healthcare systems.” Source

• In the US, where the prevalence of the Omicron variant has increased by sevenfold in just a week, top government health officials warn of a massive wave of infections that may peak in January. The US CDC described two scenarios; the worst-case predicts a potential “triple whammy” from simultaneous surges of Omicron, Delta and influenza, which could overwhelm healthcare systems and pose a huge threat to communities with low vaccination rates. Source

• WHO holds a consultation on the evidence that Omicron is evading immunity, which includes leading researchers and global experts on data synthesis. Presenters noted that vaccines may be less effective against symptomatic Omicron infections and transmission, although vaccine-induced T cell responses are likely to remain protective against severe disease – which appears to be the case in South Africa; that healthcare systems could be quickly overwhelmed by Omicron, since it has a doubling time of 2.5 days, resulting in a 50-fold increase in cases in just two weeks, and that boosters might provide a short-term benefit, but development of Omicron-specific vaccines should be considered. Source

• Britain reported a record-breaking daily total of 78,610 new cases of coronavirus – an increase of over a third in just one day. Source

• An internal review by the US CDC found that the coronavirus testing kits it developed in early 2020 were contaminated – and they had a basic design flaw that caused false positive results. Source

• Pre-print research assesses the neutralization susceptibility of vaccine-induced antibodies to the Omicron variant, using samples from 50 people who received two doses of coronavirus vaccines from Pfizer/BioNTech or Sinovac, collected within 56 days of their first dose. They found no detectable neutralizing antibodies among recipients of Coronavac, and significantly reduced titers against Omicron as compared with the original SARS-Cov-2 virus, and the Beta and Delta variants. The authors suggest development of newer-generation vaccines, noting that “…before the availability of these next generation vaccines, booster doses of currently available vaccines will likely render most people having protective levels of neutralizing antibody titers.” Source

• The International Organization for Migration announces that it will vaccinate around 7,500 of the estimated 36,000 people stranded in Yemen, where only 1.3 percent of the population has been fully vaccinated. Source

• Sanofi and GSK issue a press release to announce preliminary data from two phase III trials of their experimental recombinant adjuvanted coronavirus vaccine. In the 521-person booster trial, a booster dose of the Sanofi/GSK vaccine increased neutralizing antibodies by 9 – 43 percent among people fully vaccinated with shots from Astra/Zeneca, J & J, Moderna or Pfizer/BioNTech.

Results from another phase III trial of the vaccine, which are assessing safety and efficacy against symptomatic and severe COVID-19, are expected in Q1, 2022. Source

• In Germany, where 69.8 percent of the population has been fully vaccinated, Health Minister Karl Lauterbach announces a shortage of coronavirus vaccines that he is working to remedy, adding that it “…surprised many when we did the inventory, myself included.” Source

New England Journal of Medicine publishes results from a 29,582-person, phase III trial of the safety and efficacy of NVX-CoV2373, an adjuvanted, recombinant spike protein nanoparticle coronavirus vaccine. The trial’s objective was to assess efficacy against COVID-19 at least seven days after the second dose of vaccine; it also assessed efficacy against moderate-to-severe disease.

During three months of follow-up, 77 COVID-19 cases occurred, 14 among vaccine recipients versus 63 among placebo recipients, yielding vaccine efficacy of 90.4 percent. There were ten moderate and 4 severe cases of COVID-19, all among placebo recipients, yielding a vaccine efficacy of 100 percent against moderate-to-severe disease. Side effects were mainly mild-to-moderate, and more frequent after the second dose. Source

• Nepal initially faced shortages of coronavirus vaccines, but now it has asked that deliveries be delayed due to a lack of adequate cold storage for them. This week, the country received 2.1 million doses of the J & J vaccine from Germany, and 1.8 million doses of Covishield, which is manufactured by India’s Serum Institute and it expects 2.4 million doses of Vero Cell from China, and 676,000 doses of Pfizer from the US, via COVAX in the coming days. Badebabu Thapa, a government official dealing with logistical management of Nepal’s vaccination campaign, noted that unpredictable deliveries made planning difficult, adding, “If vaccines keep coming at the present rate, arranging warehouses for sensitive vaccines will be a herculean task.” Source

• UN Secretary General António Guterres announces that 98 countries will not achieve WHO vaccination targets – that at least 40 percent of people in all countries would be vaccinated by the end of the year, reaching 70 percent by mid-2022, adding “Vaccine inequity is giving variants a free pass to run wild — ravaging the health of people and economies in every corner of the globe,” he said. “We cannot defeat the pandemic in an uncoordinated way.”

Although over 85 billion doses of the vaccine have been administered globally, covering 43 percent of the world’s population, only eight percent of Africa’s population has been vaccinated – and it may not be able to reach the 70 percent target until Q3 of 2024. “If things do not improve – and improve fast – we face even harder times ahead,”said Mr. Guterres. Source

New England Journal of Medicine publishes results from a 29,582-person phase III trial of NVX-CoV2373, an adjuvanted, protein-based coronavirus vaccine, which has been studied against the Alpha, Beta, Epsilon, Gamma, and Iota variants. Study participants were given two injections of vaccine or placebo, 21 days apart, between 27 December 2020 and 18 February 2021, and followed until 20 April 2021.

Overall, the vaccine was 89.3 percent effective against COVID-19, and 100 percent effective against moderate-to-severe cases. All of the 14 COVID-19 cases among vaccine recipients were mild, while there were 10 moderate and 4 severe cases among the placebo group. Most adverse events were mild to moderate, and transient, with the most common being tenderness or pain at the injection site, headache, muscle aches, fatigue and weakness. Source

Return to the timeline