Omicron: Keep calm with vaccination

At least we’re learning. Remember when the early reaction to the outbreak of a deadly virus in Wuhan was to discourage people from changing their travel plans?
South Africa’s government didn’t sit on information about a new worrying variant of Sars-CoV-2, which the World Health Organization (WHO) has now dubbed omicron. It didn’t downplay it. On the contrary, authorities shared detailed slides so that countries could develop their responses. Now it’s up to governments and local authorities to adapt to a fast-changing viral picture — one that remains blurry in places.
Genomic sequencing of infections in South Africa found that the variant B.1.1.529 contained many more mutations than the dominant Delta variant. More worrying, some of the mutations occur in the area of the spike protein that is targeted by antibodies. That could mean existing vaccines will be less effective, something we should know with more certainty in the coming weeks.
The WHO dubbed the variant omicron (not “nu,” which seemed to be the Twitter consensus; and, in some conversations, a previous mutation designated “mu”). It’s also been called a “variant of concern,” which signifies it contains genetic changes that are known to affect transmissibility, disease severity or evade vaccines and therapies. Certainly, omicron’s transmissibility seems extremely high. The WHO was alerted and says the variant was identified from a specimen collected. It is already in evidence in most of South Africa’s provinces, along with Botswana, and cases have been found in Hong Kong, Israel and Belgium. The UK government said two cases of omicron have been found in Britain. It’s quite likely it has spread elsewhere, too.
While South African officials are unhappy with it, travel restrictions are the obvious first response. The UK government announced a temporary travel ban on several countries. However, when a flight from Gauteng — the South African province that includes Johannesburg — arrived in London, some 300 passengers were released into the wild with only an advisory message to self-isolate and take some tests.
Pfizer Inc says it can deliver a vaccine that would counter the new variant within 100 days of sequencing. That’s fast. Regulators like the US Food and Drug Administration are likely to speed approval processes for vaccines that are just tweaked for new variants. Pfizer estimates it could make 4 billion doses in the first 12 months. Another 8 billion doses of the Moderna Inc and AstraZeneca Plc vaccines are likely to be available in a similar time frame.
Even so, testing will need to be done on the updated vaccine. Getting it into enough arms will take many months, even with delivery systems primed by the current vaccine roll-out.
Other lines of defense will be important, too. There are questions about whether the new variant may change the effectiveness of monoclonal antibody treatments, proteins that attach to a specific target in the spike protein of the virus and can be a key tool in treating early infection and even as a prophylaxis in those vulnerable to serious illness.
Maybe we’ll get lucky. The authors of a study published in the journal Nature in September found the presence of “abundant” neutralising antibody targets on the spike protein of the Sars-Co-V-2 virus; it apparently takes a lot of mutations to escape vaccines or natural infection.
Then again, omicron has around 50 mutations and more than 30 in the spike protein, far more than the delta variant. Ten of the mutations are in the so-called receptor binding domain (RBD), which is the part of the virus that makes contact with cells first; that’s compared to two with Delta.

—Bloomberg