Preventing re-infections, more variants, and a prolonged pandemic
By Daniel R. Lucey MD, MPH, FIDSA
Emerging data since mid-January from South Africa and northern Brazil signal it is imperative to develop multivalent COVID vaccines (bivalent, trivalent, quadrivalent) for international use.
An alternative strategy that is unlikely to succeed internationally is monovalent “booster” vaccines containing either the variant 501Y.V2 (found first in South Africa) or the P.1 variant (found first in Menaus, Brazil) or the B.18.104.22.168 variant (found first in the UK). Each of these multiple variants continue to be found in increasing numbers of nations on different continents. More variants are emerging and more surely exist.
How many of these monovalent variant “booster” vaccines will cross-protect at a high level against other variants, or the current global virus (with the D614G mutation) causing most of the pandemic today?
Importantly, the perspective must be kept in mind of the great majority of the world’s population that has never received a single dose of any COVID-19 vaccine. For them such a “booster” dose vaccine with a single variant virus will not be a “booster” at all. Instead, it will be their first dose of a COVID-19 vaccine.
The Jan. 28 Novavax synopsis of its 4,400-person adjuvanted protein vaccine study in South Africa included the statement (in boldtype below) that 1/3 of those enrolled had antibody evidence of a prior non-variant SARS-CoV-2 infection, and that some had been re-infected with the variant 501Y.V2:
“Importantly in this trial, approximately 1/3 of the patients enrolled (but not included in the primary analyses described above) were seropositive, demonstrating prior COVID-19 infection at baseline. Based on temporal epidemiology data in the region, the pre-trial infections are thought to have been caused by the original COVID-19 strain (i.e., non-variant), while the subsequent infections during the study were largely variant virus. These data suggest that prior infection with COVID-19 may not completely protect against subsequent infection by the South Africa escape variant…”
As noted here Jan. 28 Novavax stated they will begin work on a booster and/or combination-bivalent vaccine.
Similarly, as commented on here Jan. 26, Moderna and Pfizer/BioNTech are also assessing moving forward with a vaccine that would include this variant in South Africa.
Also, this past week PAHO/WHO reported in the city of Manaus, in northern Brazil, variant P.1 was found in 85% of sequenced viruses compared with zero percent from March through November and 52% in December. As noted here Jan. 30. Although only one case of re-infection has been reported with P.1 so far, more should be anticipated. The reason is that the current overwhelming epidemic in Manaus is occurring despite an earlier overwhelming epidemic that was estimated to have reached an attack rate of 76% by last October, as reported in print Jan. 15 in Science.
Daniel Lucey, M.D. MPH, FIDSA, FACP, is a Clinical Professor of Medicine at Dartmouth Geisel School of Medicine, Infectious Disease adjunct Professor at Georgetown Medical Center, senior scholar at Georgetown Law, Anthropology Research Associate at the Smithsonian Museum of Natural History and a member of the Infectious Diseases Society of America Global Health Committee. He served as a volunteer to outbreaks overseas including hands-on Ebola patient care in Sierra Leone and Liberia (Doctors without Borders) 2014, MERS 2013, SARS 2003, as well as HIV, H5N1, Zika, yellow Fever, and pneumonic plague 2017 (with WHO/USAID/CDC). Since Jan. 6, 2020 he has contributed over 75 posts to Science Speaks on COVID-19 and traveled to China in February 2020. He initially proposed, then fundraised and helped design the content for 2018-2022 Smithsonian Exhibition on Epidemics due to zoonotic viruses. From 1982-1988 he trained at University of California San Francisco and Harvard and was an attending physician at the NIH (NIAID) in the 1990s while in the US Public Health Service.