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U.S. Government Supports COVID-19 Vaccine Effectiveness Study
September 13, 2022

LUSAKA – On September 12, Zambia published findings from a COVID-19 vaccine effectiveness study in the American Journal of Tropical Medicine and Hygiene (AJTMH).  The study, which was led by the Field Epidemiology Training Program (FETP) under the Zambian National Public Health Institute (ZNPHI), provides real-world evidence of vaccine effectiveness.  The findings showed that COVID-19 vaccination demonstrated a 65 percent effectiveness against COVID-19 infection and 73 percent effectiveness against symptomatic COVID-19 infection.  The U.S. government, through the U.S. Centers for Disease Control and Prevention (CDC), helped establish the Zambian FETP in 2014 to increase the number of field epidemiologists in Zambia.

Dr. John Simwanza, an FETP resident, led the investigation in December 2021 after learning of a COVID-19 outbreak in a Zambian prison shortly after Zambia detected the Omicron variant.  Dr. Simwanza said “These findings are important for Zambia because most clinical trials were done outside Africa.”  Zambia shared the results with the World Health Organization in January and subsequently released as a preprint in May on medRxiv here.  The peer-reviewed publication is available from AJTMH here.

The study demonstrates the importance of rapid outbreak investigation in a closed setting to demonstrate COVID-19 vaccine effectiveness.  Vaccination remains a critical tool in decreasing COVID-19 transmission and severity, especially when coupled with prevention measures such as using well-fitting facemasks when in crowded settings, good hand washing hygiene, holding gatherings in outdoor settings when possible, and ensuring adequate ventilation for gatherings indoors.

This study also demonstrates the U.S. government’s partnership with ZNPHI to strengthen the public health sector in Zambia.  To date, CDC has helped mentor over 40 advanced FETP residents through a a two-year training and mentorship program and more than 250 frontline FETP participants through a three-month training program.  Since 2000, CDC has partnered with the Ministry of Health, ZNPHI, and provincial health offices in Zambia to address HIV, tuberculosis, malaria, and other infectious diseases like COVID-19.