By Daniel R. Lucey MD, MPH, FIDSA
In its weekly COVID-19 epidemiology update this week the World Health Organization stated that the “Lambda” was designated a variant of interest “based upon evidence of continued emergence and suspected phenotypic implications” (boldtype below was added).
“Authorities in Peru reported that 81% of COVID-19 cases sequenced since April 2021 were associated with Lambda. Argentina reported increasing prevalence of Lambda since the third week of February 2021, and between 2 April and 19 May 2021, the variant accounted for 37% of the COVID-19 cases sequenced.
“In Chile, prevalence of Lambda has increased over time, accounting for 32% of sequenced cases reported in the last 60 days – co-circulating at similar rates to variant Gamma (33%), but outcompeting variant Alpha (4%) over the same period.”
Although further studies are required to assess whether Lambda will become a Variant of Concern e.g., if it indeed outcompetes the Gamma variant of concern that has spread across much of Brazil and neighboring nations in 2021, WHO noted:
“Lambda carries a number of mutations with suspected phenotypic implications, such as a potential increased transmissibility or possible increased resistance to neutralizing antibodies.”
Studies of the multiple vaccines in use across South America to determine the degree of protection after one and two doses against this Lambda variant are urgently needed as well as risk of reinfection.
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 more than 100 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 U.S. Public Health Service.