Herewith three items of pandemic news you may have missed recently: Two more Russian vaccines; a primer on T-cell immunity; and fabulous results from a real-world study of vaccine effectiveness. Plus news briefs and two fripperies.
90% effective in the real world
By now you have heard that a study of vaccine effectiveness outside of a formal trial concluded that the two mRNA vaccines provide 90% protection against infection after two shots.
Note the italics. The vaccines were all designed to prevent severe outcomes of Covid-19: hospitalization, ICU admission, death. This they do splendidly. What couldn’t be guaranteed is sterilizing immunity against infection with the SARS-CoV-2 virus. And, in line with earlier indications out of Israel and the UK, the vaccines do indeed provide that.
Volunteers enjoyed 80% protection even after a single shot of the two-dose vaccines.
Helen Branswell of Stat News summarized the results this way:
The implications are vast and all positive. Herd immunity might be reachable. As this news spreads, more of the vaccine hesitant may be convinced to roll up their sleeves.
The study subjects were nearly 4,000 front-line and essential workers — teachers, firefighters, police, health-care staff — in six states. During the worst of the winter pandemic peak, from mid-December to mid-March, they took nasal swabs or saliva samples at home and sent them for processing. This methodology caught asymptomatic and pre-symptomatic infections — 58% of the total — as well as symptomatic Covid-19, which was the basis of most previous studies.
The study so far has nothing to say about the impact of viral variants. The researchers are sequencing samples and will have a follow-up on the subject in a month or so.
T-cell immunity 101
On the most recent This Week in Virology podcast, TWiV #736, guest Alessandro Sette of the La Jolla Institute for Immunology discourses on T cells, the aspect of the immune system of which he has made a career. Sette and his team at La Jolla recently released a preprint, now in peer review, which reports:
This is excellent news, and should put to rest the minds of all those (like me) who have been hearing news of decreased efficacy of antibody responses in the presence of the viral variants. Antibodies are but one arm of the human immune system; in fact they represent the one that is the easiest to study.
Another reason why I wanted to commend this TWiV episode to you: In it Sette gives the most comprehensible explanation of what happens when the immune system encounters SARS-CoV-2 that I have yet heard. If you have any interest at all in bolstering your understanding of the role of T cells in human immunity, devote 8-1/2 minutes of your time to this video beginning at 0:07:30.
And the final reason for linking this TWiV: the host reads a letter I wrote to the podcast (not my first letter but first time on-air). In fact what I wrote to them was a poem, to be sung to the tune of Mister Sandman.
Vincent Raciniello’s dramatic reading (none of the hosts wanted to sing it) starts at 1:45:23. I got a public pat on the back for mentioning T cells.
Two more Russian vaccines
Like the US and China, Russia has a number of vaccines in the development pipeline (reports indicate upwards of 20). The German broadcaster Deutsche Welle is running a profile of the next two to advance after the widely covered Sputnik V.
In a Russian tradition that hasn’t changed since the Soviet era, not much news has emerged from the country about these vaccines, which are called EpiVacCorona and CoviVac. (Confusingly, another vaccine under development, by Codagenix of New York, is named Covi-Vac. Even more confusingly, sometimes the Russian offering is spelled with the hyphen.) Also in the Russian tradition, both Sputnik V and the emerging vaccines have been authorized by government authorities long before Phase III trials have produced results.
EpiVacCorona was authorized last October, a month before its Phase III began. (Sputnik had gotten the nod in August.) CoviVac’s authorization came in February. These three vaccines make up the backbone of Russia’s plan to vaccinate the majority of its citizens by the fall.
EpiVacCorona was developed by the Vector Institute in Siberia, which is an organ of Russia’s consumer protection agency. The Phase III trial is registered with ClinicalTrials.gov; results are expected in August. Outcome of the Phase I/II trial was published in a somewhat obscure Russian journal and Western experts have questioned its methodology. The Tass news agency promises publication soon in “foreign scientific journals.”
The vaccine was developed on a “protein subunit” platform, the first such to achieve any nation’s authorization. (Novavax is built on a similar technology.) EpiVacCorona seems to use an aluminum hydroxide adjuvant.
CoviVac was developed by the Chumakov Centre, part of the Russian Academy of Sciences. It is an inactivated whole-virus vaccine. For this reason Chumakov says it may be more effective against viral variants. Little more is known about the vaccine.
See the Brief below about Russia’s export of vaccines motivated by diplomacy.
- GSK signs up to manufacture Novavax for UK — Novavax should get the green light soon in the UK, after a successful Phase III in that country and in South Africa. (We are still waiting for a readout from the larger US Phaase III.) The company has been cranking up manufacturing in anticipation of authorizations in multiple countries, and the GlaxoSmithKline hookup is the latest manifestation. See this updated chart of the deals vaccine makers have inked with manufacturing partners.
- Vaccine diplomacy — The Atlantic has a piece that throws light on China’s and Russia’s geopolitical aspirations in distributing their vaccines around the world. Russia has sent over 4 million doses abroad, and China over 100 million. These countries’ actions contrast with the vaccine nationalism being played out in the US and Europe. But the funny thing is, our adversaries’ conspicuous generosity works to our advantage too. We all benefit when more of the world is protected.
- Equity of the worldwide vaccine rollout — This dashboard (click on “Distribution”) reports on how the global distribution of vaccines is coming. In a word: slowly. The page has a useful interactive table in which you can choose up to five vaccines, from those approved somewhere in the world, to compare across multiple dimensions. Of interest is the vaccines’ score on the ONE Vaccine Access Test, a rating of how friendly the product is for distribution in less developed and undeveloped countries.
Now as a reward for your persistence in getting this far, we have two fripperies on offer. The first harks back to the Ever Given, the massive container ship that spent a week blocking the Suez Canal (pictured top left). Between the previous Update and now, that ship has sailed. But in case you miss it as much as I do: enjoy this interactive map that lets you place a scaled-to-fit Ever Given so as to block any waterway or street of your choice anywhere in the world.
Our second frippery is a political guessing game. The NY Times runs this engaging quiz in which you are dropped into a Google Street View of some random neighborhood in the US and you have to guess whether that district voted for Biden or for Trump. Much more difficult than you might think. I scored at the 71st percentile on a first attempt and 96th percentile on the next. Let me know in the comments how you make out. (The Times’s quiz owes a debt of gratitude to the venerable Geoguessr, in which you must suss out your location somewhere in the world of Street View.)