I’ve felt that while the winter is going to be bad from a Covid perspective – rising cases, including breakthrough cases, underboosted population – that we have the tools to end the pandemic. Booster shots restore vaccine protection and Pfizer’s Paxlovid is incredibly effective when taken within 3 days of symptom onset.
While we’ve seen virus variants, we haven’t seen rapid mutation that escapes immunity and also involves greater fitness – so that the virus spreads faster and in vaccinated and previously infected populations. Indeed, vaccines remain protective even though we’re still vaccinating against the original Wuhan strain of the virus and haven’t permitted updated vaccines to be used.
However the Nu variant is concerning.
— Eric Topol (@EricTopol) November 25, 2021
This new South African variant was discovered on Tuesday, based on samples taken mid-month. It’s been found around the world in travelers originating in South Africa and surrounding countries. The U.K. has shut down flights from South Africa, Namibia, Zimbabwe, Botswana, Lesotho and Eswatini. Some other countries in Europe have taken similar steps, along with Israel.
That’s not going to stop it if it is indeed a more fit variant of the virus. It’ll spread beyond the countries where it is currently most prevalent and from there it will sneak into the countries blocking flights. Only island nations in true lockdown can block it, as we learned throughout the pandemic. And as the virus continues to spread wildly travel restrictions don’t stop the spread of mutation because the virus continues to mutate within countries where it’s already spreading.
This variant has multiple spike protein mutations that could help it become more transmissible and also evade immunity. Whether this variant becomes dominant or not, it’s suggestive that there are more mutations in the virus that are possible – countering prevailing wisdom that significant mutation wouldn’t be possible while continuing to infect humans. Indeed, this variant even evades identification in current testing – PCR tests amplify three virus genomes but these tests can amplify just two of the genomes with this variants. So when we talk about having identified fewer than 100 cases that’s because we weren’t really looking for it. But when researchers went looking for cases that had only genomes amplified that corresponded with case spikes.
Regeneron monoclonal antibodies are likely less effective against the Nu strain, though it appears that AstraZeneca’s cocktail will fare better. Meanwhile Pfizer’s Paxlovid was so effective its phase 3 trial was cut short, because it was deemed unethical to give anyone a placebo when they could have the real thing. Yet the FDA hasn’t indicated when anyone will be permitted to have it, since they haven’t yet deemed it safe and effective. It seems like we may need it…
Update: WHO has named this variant “Omicron” rather than Nu in the Greek alphabet which was next. That also means they’ve skipped over Greek letter Xi. Heh.