Chikungunya Outbreak in the Republic of the Congo, 2019-Epidemiological, Virological and Entomological Findings of a South-North Multidisciplinary Taskforce Investigation

• Published in: Viruses Vol. 12; no. 9; p. 1020
• Main Authors: Vairo, Francesco, Aimè Coussoud-Mavoungou, Martin Parfait, Ntoumi, Francine, Castilletti, Concetta, Kitembo, Lambert, Haider, Najmul, Carletti, Fabrizio, Colavita, Francesca, Gruber, Cesare E M, Iannetta, Marco, Messina, Francesco, Lanini, Simone, Ulrich Judicaël, Biez, Giombini, Emanuela, Montaldo, Chiara, Portella, Chantal, Diafouka-Diatela, Steve, Rueca, Martina, Kock, Richard, Bartolini, Barbara, Mboera, Leonard, Munster, Vincent, Fischer, Robert, Seifert, Stephanie, Muñoz-Fontela, César, Escudero-Pérez, Beatriz, Gomez-Medina, Sergio, Nelson, Emily V, Kjia Tungu, Patrick, Nicastri, Emanuele, Puro, Vincenzo, Di Caro, Antonino, Capobianchi, Maria Rosaria, Mikolo, Jacqueline Lydia, Zumla, Alimuddin, Ippolito, Giuseppe, On Behalf Of The Pandora-Id-Net Consortium Chikungunya Outbreak Group Taskforce
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 13.09.2020; MDPI
• Subjects: Adolescent; Adult; Aedes - virology; Aedes aegypti; Aedes albopictus; Aedes spp; Animal bites; Animals; arbovirus; Bayes Theorem; Bayesian analysis; chikungunya; Chikungunya Fever - epidemiology; Chikungunya Fever - virology; Chikungunya virus; Chikungunya virus - classification; Chikungunya virus - genetics; Chikungunya virus - physiology; Child; Child, Preschool; Congo - epidemiology; Disease; Disease Outbreaks; Ebola virus; Epidemics; Epidemiology; Female; Genomes; Genotype & phenotype; Humans; Laboratories; Larva; Male; Middle Aged; mosquito; Mosquito Vectors; Mosquitoes; Mutation; outbreak; Patients; Pest outbreaks; Phylogenetics; Phylogeny; Polymerase chain reaction; Republic of Congo; Software; Trees; Young Adult; Zoonoses; Congo; Indian Ocean; Gabon; Aedes spp; ONE-HEALTH; outbreak; chikungunya; Republic of Congo; arbovirus; mosquito
• ISSN: 1999-4915; 1999-4915
• DOI: 10.3390/v12091020

The Republic of Congo (RoC) declared a chikungunya (CHIK) outbreak on 9 February 2019. We conducted a ONE-Human-Animal HEALTH epidemiological, virological and entomological investigation. Methods: We collected national surveillance and epidemiological data. CHIK diagnosis was based on RT-PCR and CHIKV-specific antibodies. Full CHIKV genome sequences were obtained by Sanger and MinION approaches and Bayesian tree phylogenetic analysis was performed. Mosquito larvae and 215 adult mosquitoes were collected in different villages of Kouilou and Pointe-Noire districts and estimates of mosquitos' CHIKV-infectious bites obtained. We found two new CHIKV sequences of the East/Central/South African (ECSA) lineage, clustering with the recent enzootic sub-clade 2, showing the A226V mutation. The RoC 2019 CHIKV strain has two novel mutations, E2-T126M and E2-H351N. Phylogenetic suggests a common origin from 2016 Angola strain, from which it diverged around 1989 (95% HPD 1985-1994). The infectious bite pattern was similar for 2017, 2018 and early 2019. One pool was RT-PCR positive. The 2019 RoC CHIKV strain seems to be recently introduced or be endemic in sylvatic cycle. Distinct from the contemporary Indian CHIKV isolates and in contrast to the original Central-African strains (transmitted by ), it carries the A226V mutation, indicating an independent adaptive mutation in response to vector replacement ( vs ).