COVID-19 Variants and Vaccines’ Effectiveness



Day 304: Stay Safe Minnesota

Based on the limited current vaccine studies against two dominant COVID-19 variants suggests that Moderna and Pfizer vaccines may work against the British variant but little concern with the South African variant.

Dr David Kennedy, Professor of Evolutionary Biology at the Penn State writes in an article in The Conversation that he “studies the link between the transmission and evolution of infectious diseases especially the effects of vaccines on pathogen evolution and the effects of pathogen evolution on the impact of vaccines“. Explaining the COVID-19 mutations in spike regions and its effect on current vaccines, Dr Kennedy writes:

” .. the spike protein enables the virus to enter human cells, and it is a key target of our immune response, both in fighting off the virus during infection and in protecting us from disease following vaccination with the Pfizer and Moderna vaccines. [..] These mutations may also alter how well the host’s immune system combats the virus, potentially reducing the efficacy of the current vaccines.”

Citing vaccine experts, The New York Times reporter Apoorva Mandavilli writes “all viruses mutate, and it’s no surprise that some of those mutations sidestep the body’s immune defenses. Some mutations don’t improve on the original, and fade away. Others add to the pathogen’s power, by making it more contagious — like the variant first identified in Britain — more fit, or less susceptible to immunity”.

Dr. Francis S. Collins, director of the U.S. National Institutes of Health, said on MSNBC on Saturday that “the Pfizer and Moderna vaccines hold up against the British-affiliated variant, but he said the variant first found in South Africa, called B.1.351, is ‘more of a concern‘.”

(The British variant) seems to have a somewhat more significant effect on the vaccine response, although it still looks like it would be protected. Fortunately we have not yet seen that variant in the U.S., but it would not surprise me if it appears.”

Dr. Francis S. Collins, director of the U.S. National Institutes of Health (source: The New York Times)

Vaccine Effectiveness to COVID Variants

Most vaccines by stimulating the body to produce antibodies against the coronavirus, like seasonal flu, SARS-2 or CIVID-19. “Both the Pfizer and Moderna vaccines work by training our immune systems to recognize a specific version of the viral spike protein. The version of the spike protein used by the vaccines was designed to match that of the old virus, not that of the B.1.1.7 virus. This means that the vaccines might become less effective than expected should this new virus spread widely” explains Dr Kennedy.

Vaccine-virus mismatch is an ongoing challenge for scientists charged with developing the seasonal flu vaccine. But even with a virus-vaccine mismatch, the flu vaccine reduces the likelihood, and the severity, of disease. [..] it’s too early to say whether and how this new variant will influence the overall effectiveness of the Pfizer and Moderna vaccines.

Dr David Kennedy in The Conversation

Dr. Michel Nussenzweig, an immunologist at Rockefeller University in New York, who is studying effectiveness COVID vaccines against variants told the New York Times “Existing vaccines will still prevent serious illness, and people should continue getting them. But the vaccines may not prevent people from becoming mildly or asymptomatically infected with the variants.”

“The mRNA technology on which the Pfizer and Moderna vaccines rely can be altered in a matter of weeks, and far more easily than the process used to produce flu vaccines. But it would be wise to prepare for this eventuality now and think through not just the technical aspects of updating the vaccines, but the testing, approval and rollout of those vaccines,” vaccine experts told the Times.

COVID-19 Vaccination Watch

According to the US Centers for Disease Control and Prevention (CDC) COVID vaccination tracker page (as of Jan 26, 9 a.m.) 44,394,075 doses have been distributed and 23,540,994 doses administered. According MDH COVID-19 Response vaccine data (as of Jan 24) a total of 353,113 doses of Covid-19 (Pfizer & Moderna) vaccines have been administered in Minnesota. According to the MDH latest tally (as of Jan 26, 11 a.m.) the confirmed COVID-19 cases in Minnesota are 456,490 (out of 6,399,553 tested) with 6,106 deaths.