Prevalence of SARS-CoV-2 among high-risk populations in Lomé (Togo) in 2020

Halatoko, W. A.; KONU, Y. R.; Gbeasor-Komlanvi, F. A.; Sadio, A. J.; Tchankoni, M. K.; Komlanvi, K. S.; Salou, M.; Dorkenoo, A. M.; Maman, I.; Agbobli, A.; Wateba, M. I.; Adjoh, K. S.; Goeh Akue, E.; Kao, Y.-b.; Kpeto, I.; Pana, P.; Kinde-Sossou, R.; Tamakloe, A.; Nayo-Apetsianyi, J.; Assane, S.-P. H.; Prince-David, M.; Awoussi, S. M.; Djibril, M.; Mijiyawa, M.; Dagnra, A. C.; Ekouevi, D. K.

Objective: This survey aims at estimating the prevalence of SARS-CoV-2 in high risk populations in Lomé. Methods: From April 23rd to May 8th 2020, we recruited a sample of participants from five sectors: healthcare, air transport, police, road transport and informal. We collected oropharyngeal swab for direct detection through real time reverse transcription polymerase chain reaction (rRT-PCR), and blood for antibodies detection by serological tests. The overall prevalence (current and past) of infection was defined by positivity for both tests. Results: A total of 955 participants with a median age of 36 (IQR 32-43) were included and 71.6% (n=684) were men. Around 22.1% (n=212) were from the air transport sector, 20.5% (n=196) in the police, and 38.7% (n=370) in the health sector. Seven participants (0.7%, 95% CI: 0.3-1.6%) had a positive rRT-PCR at the time of recruitment and nine (0.9%, 95% CI: 0.4-1.8%) were seropositive for IgM or IgG against SARS-CoV-2. We found an overall prevalence of 1.6% (n=15), 95% CI: 0.9-2.6%. Conclusion: The prevalence of the SARS-CoV-2 infection among high-risk populations in Lomé was relatively low and could be explained by the various measures taken by the Togolese government. Therefore, we recommend targeted screening.