Detection frequency of SARS-CoV-2 over the different waves of COVID-19 between 2020 and 2022 in Cameroon

Cameroon faced several waves of COVID-19 epidemics between 2020 and 2022. The epidemic peaks were characterized by variations in the number of positive cases and major variants. The aim of this study was to determine the frequency of COVID-19 in Cameroon during the different epidemic waves.

nasopharyngeal samples were collected in different regions of Cameroon between 2020 and 2022. The Daan Gene kit (DaAn Gene, Guangzhou, Guangdong Province, China) was used to detect SARS-CoV-2 in the samples by RT-PCR assay. Excel 2013 software was used to record participants´ sociodemographic characteristics (age, sex, sampling date) and SARS-CoV-2 test results. Statistical analyses were performed using IBM SPSS version 25 software.

from 16 March 2020 to 31 December 2022, 142,850 samples were tested. Participants ranged in age from 1 to 99 years with a M/F sex ratio of 1.32. Of the participants tested, 17,463 (12.2%) were positive for SARS-CoV-2. The SARS-CoV-2 detection rate decreased over time and was highest in 2020 (15.6%; 7255/46466) as opposed to 2021 (12.7%; 8859/69867) and 2022 (5.1%; 1349/26383). Four peaks of COVID-19 circulation were identified: May 2020, March 2021, September 2021 and December 2021. Risk factors for increased detection of SARS-CoV-2 were being older than 65 years and being from the Littoral region.

the SARS-CoV-2 positivity rate in Cameroon decreased over the years, probably due to compliance with the barrier measures implemented by the Cameroonian government to reduce transmission rates.