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

Abstract

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 Aedes (Ae.) 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 Ae. albopictus 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 Ae. aegypti), it carries the A226V mutation, indicating an independent adaptive mutation in response to vector replacement (Ae. albopictus vs Ae. aegypti).

Seroprevalence and associated risk factors of chikungunya, dengue, and Zika in eight districts in Tanzania

“…Recent DENV outbreaks have been reported in Tanzania (Vairo et al, 2012;Ward et al, 2017;Chipwaza et al, 2020), Mozambique (Mugabe et al, 2018), Ghana (Amoako et al, 2018), Sudan (Elaagip et al, 2020), Benin, Cote d'Ivoire, and Mauritius (WHO, 2019). Outbreaks of chikungunya have been reported in Kenya (Kariuki Njenga et al, 2008), the Republic of Congo (Vairo et al, 2020), and the Reunion Islands (Vazeille et al, 2007). Zika infections have been reported in Cape Verde (Kindhauser et al, 2016;Lourenço et al, 2018), Guinea Bissau (Gulland et al, 2016), Mozambique (Gudo et al, 2016), and Angola (Hill et al, 2019).…”

COVID-19, Chikungunya, Dengue and Zika Diseases: An Analytical Platform Based on MALDI-TOF MS, IR Spectroscopy and RT-qPCR for Accurate Diagnosis and Accelerate Epidemics Control

“…The American continent is a hotspot for dengue, with ongoing resurface in annual peaks [ 32 ]. A recent upsurge of chikungunya virus (CHIKV) cases has been reported in Africa (Democratic Republic of Congo, 2019), Europe (Italy, 2017), and America (Brazil) [ 33 ].…”

Epidemiology and Laboratory Diagnostics of Dengue, Yellow Fever, Zika, and Chikungunya Virus Infections in Africa

“…These countries include Angola, Benin, Burundi, Cameroon, Central African Republic, Chad, Comoros, Cote d’Ivoire, Democratic Republic of the Congo, Djibouti, Equatorial Guinea, Eritrea, Ethiopia, Gabon, Guinea, Kenya, Madagascar, Malawi, Mauritius, Mayotte, Mozambique, Nigeria, Republic of the Congo, Réunion, Senegal, Seychelles, Sierra Leone, South Africa, Somalia, Sudan, Tanzania, Uganda, and Zimbabwe [ 160 , 161 , 162 ] ( Figure 6 ). During the period from 2004 to 2020, CHIKV was reported in Kenya, Comoros, La Réunion, Mauritius, Seychelles, Madagascar, Mayotte, Cameroon, Tanzania, Gabon, Republic of the Congo, Senegal, and Angola [ 94 , 96 , 98 , 102 , 103 , 163 , 164 , 165 , 166 , 167 , 168 ]. Despite CHIKV being discovered in East Africa seventy years ago, there is still a lack of data on the prevalence of the infection and the disease burden in Africa.…”