Study Traces Spread of Delta Variant in Liberia

In June 2021, a surge in cases of COVID-19 in Liberia led researchers to investigate its cause. The subsequent analysis of 267 nasopharyngeal swab samples collected from hospitalized patients across the country from March to July 2021, revealed that the Delta variant was already circulating in Liberia in early March after which it went on to become the dominant strain by June. Mutations and deletions suggest that SARS-CoV-2 Delta was introduced from multiple sources. The findings appear in the journal Emerging Infectious Diseases.

The research study was performed under and supported by an ongoing partnership to build infectious disease surveillance capacity around the world including Liberia, as part of a larger Global Alliance for Pandemic Prevention (GAPP) under the leadership of W. Ian Lipkin at the Center for Infection and Immunity (CII), Columbia University Mailman School of Public Health.

The study was led by Nischay Mishra, PhD, assistant professor of epidemiology within CII, and Bode Shobayo, deputy director for research at the National Public Health Institute of Liberia.

“Liberia should continue surveillance for SARS-CoV-2 variants of concern to determine whether additional vaccination or public health measures are needed to curb severe disease and future case surges in the country,” the authors write.

Co-authors include Mitali Mishra, Stephen Sameroff, Alexandra Petrosov, James Ng, Alper Gokden, Komal Jain, Thomas Briese, and W. Ian Lipkin (Columbia University); Jane MaCauley (National Public Health Institute of Liberia); Courtney Renken, James Tanu Duworko, Moses Badio, Lisa Hensley (U.S. National Institutes of Health, Partnership for Research on Infectious Diseases in Liberia); Wilhemina Jallah (Liberia Ministry of Health).

Financial support was provided by the Skoll Foundation for the Global Alliance for Pandemic Prevention (GAPP grant 20-45017), the Tong Tsung and Wei Fong Chao Foundation (grant GT007457), and the Chau Hoi Sheun Foundation (grant GT007457).