Emergence of the East-Central-South-African genotype of Chikungunya virus in Brazil and the city of Rio de Janeiro may have occurred years before surveillance detection

Abstract

Brazil, which is hyperendemic for dengue virus (DENV), has had recent Zika (ZIKV) and (CHIKV) Chikungunya virus outbreaks. Since March 2016, CHIKV is the arbovirus infection most frequently diagnosed in Rio de Janeiro. In the analysis of 1835 syndromic patients, screened by real time RT-PCR, 56.4% of the cases were attributed to CHIKV, 29.6% to ZIKV, and 14.1% to DENV-4. Sequence analyses of CHIKV from sixteen samples revealed that the East-Central-South-African (ECSA) genotype of CHIKV has been circulating in Brazil since 2013 [95% bayesian credible interval (BCI): 03/2012-10/2013], almost a year before it was detected by arbovirus surveillance program. Brazilian cases are related to Central African Republic sequences from 1980’s. To the best of our knowledge, given the available sequence published here and elsewhere, the ECSA genotype was likely introduced to Rio de Janeiro early on 2014 (02/2014; BCI: 07/2013-08/2014) through a single event, after primary circulation in the Bahia state at the Northestern Brazil in the previous year. The observation that the ECSA genotype of CHIKV was circulating undetected underscores the need for improvements in molecular methods for viral surveillance.

Inactivation of yellow fever virus with amotosalen and ultraviolet A light pathogen‐reduction technology

“…PR technology with high inactivation capacity is particularly important to safeguard the blood supply in areas impacted by emerging arboviruses. Not only such viruses can emerge in the human population months to years before surveillance detects them, [22][23][24][25] but most infections are commonly asymptomatic. 26,27 In 45% of the YF cases, symptoms may develop 3 to 6 days after infection.…”

Desenvolvimento de insumos para diagnóstico e/ou vacina do vírus chikungunya (CHIKV)

“…Hoje, destaca-se três linhagens de CHIKV, sendo elas a linhagem África Ocidental, Asiática e Leste/Central/ Sul Africano. Cada linhagem tem uma ligação específica com o vetor, tendo assim, diferentes graus e consequentemente, causando diferentes respostas imunes e o período de incubação do vírus perdura de 4 a 12 dias (SOUZA et al 2019. LUMSDEN, 1955.…”