RESUMEN
The control and management of malaria are linked to the quality of diagnosis. We sought to estimate the performance of routine microscopy for malaria diagnosis and assess the prevalence of submicroscopic Plasmodium (P.) falciparum infection among febrile patients in two healthcare facilities in Mossendjo, the Republic of the Congo. A cross-sectional study was conducted between January and December 2022. A total of 650 and 234 patients with signs of uncomplicated malaria were enrolled at the Centre de Sante Intégré (CSIMSJ) and Hôpital de Base (HBMSJ), respectively. Two thick blood smears were performed for each patient, one analyzed by routine microscopists and the other by an expert. The msp-1 and msp-2 genes were genotyped to detect submicroscopic P. falciparum infection. At the CSIMSJ, the sensitivity was 49.5% and the specificity was 88.6%. The positive and negative predictive values were 77.7% and 68.7%, respectively. At the HBMSJ, the sensitivity was 32.9% and the specificity was 79.4%. The positive and negative predictive values were 44.8% and 69.5%, respectively. P. falciparum was the only species detected by routine microscopists, while experts identified some cases with P. malariae and P. ovale. The proportion of submicroscopic infections was 35.75%. Children under 5 years old had higher rates of parasitemia. However, submicroscopic infections were more pronounced in the adult group. The performance of routine malaria microscopists at Mossendjo was inaccurate at both sites. With the large proportion of submicroscopic infection, malaria management at Mossendjo requires the improvement of microscopists' skills and the concomitant use of RDTs.
RESUMEN
Following the emergence of SARS-CoV-2, cases of pets infected with variants circulating among humans were reported. In order to evaluate the occurrence of SARS-CoV-2 circulation among pets in the Republic of the Congo, we conducted a ten-month study of dogs and cats living in COVID-19-positive households in Brazzaville and neighboring localities. Real-time PCR and the Luminex platform were used to detect SARS-CoV-2 RNA and antibodies to SARS-CoV-2 RBD and S proteins, respectively. Our results show for the first time the simultaneous circulation of several variants of SARS-CoV-2, including viruses from clades 20A and 20H and a putative recombinant variant between viruses from clades 20B and 20H. We found a high seroprevalence of 38.6%, with 14% of tested pets positive for SARS-CoV-2 RNA. Thirty-four percent of infected pets developed mild clinical signs, including respiratory and digestive signs, and shed the virus for about one day to two weeks. These results highlight the potential risk of SARS-CoV-2 interspecies transmission and the benefits of a "One Health" approach that includes SARS-CoV-2 diagnosis and surveillance of viral diversity in pets. This approach aims to prevent transmission to surrounding wildlife as well as spillback to humans.