Seroprevalence, spatial dispersion and factors associated with flavivirus and chikungunya infection in a risk area: a population-based seroprevalence study in Brazil

Abstract

Background The State of Ceará, in Northeastern Brazil, suffers from a triple burden of arboviruses (dengue, Zika and chikungunya). We measured the seroprevalence of chikungunya, dengue and Zika and its associated factors in the population of Juazeiro do Norte, Southern Ceará State, Brazil. Methods A cross-sectional study of analytical and spatial analysis was performed to estimate the seroprevalence of dengue, Zika and chikungunya, in the year 2018. Participants were tested for IgM and IgG against these three viruses. Those with IgM and/or IgG positive tests results were considered positive. Poisson regression was used to analyze the factors associated with positive cases, in the same way that the spatial analysis of positive cases was performed to verify whether the cases were grouped. Results Of the 404 participants, 25.0% (103/404) were positive for CHIKV, 92.0% (373/404) for flavivirus (dengue or Zika) and of these, 37.9% (153/404) samples were classified as probable dengue infection. Of those who reported having had an arbovirus in the past, positive CHIKV cases had 58.7% arthralgia (PR = 4.31; 95% CI: 2.06–9.03; p = 0.000) mainly in the hands, ankles and feet. Age over 60 years had a positive association with cases of flavivirus (PR = 1.29; 95% CI: 1.09–1.54; p = 0.000). Fever, muscle pain, joint pain and skin rash were the most reported symptoms (46.1, 41.0, 38.3 and 28.41%, respectively). The positive cases of chikungunya and dengue or Zika were grouped in space and the city center was most affected area. Conclusions Four years after the introduction of CHIKV, where DENV has been in circulation for over 30 years, 1/4 of the population has already been exposed, showing the extent of the epidemic. The measured prevalence was much higher than that reported by local epidemiological surveillance.

Chikungunya virus seroprevalence in asymptomatic blood donors during an outbreak in the Federal District of Brazil

“…For instance, the overall CHIKV seroprevalence varies from 20.00% to 57.14% in studies from Bahia State [14][15][16] and from 25.49% and 70.66% in studies from Ceara State. 17,18 The isolated IgG seroprevalence in an urban slum from Salvador (Bahia State) was 11.79%. 19 In Rio de Janeiro city (Southeastern of Brazil), which is distantly located from CHIKV endemic regions, the estimated CHIKV seroprevalence was also higher (17.50%) 20 Lastly, blood donors represent a specific population group, the seroprevalence of which is useful to estimate the dissemination of a given infectious agent but cannot be extrapolated to the general population.…”

Peculiarities of Zika Immunity and Vaccine Development: Lessons from Dengue and the Contribution from Controlled Human Infection Model

“…These numbers are not far from those reported in Brazil, where a serological survey estimated that ZIKV seroprevalence exceeded 60% in Salvador (state of Bahia) [ 18 ]. Likewise, the prevalence of flavivirus infections was estimated to be around 92% in the state of Ceará in 2018, of which only 37% were considered to be associated with DENV [ 19 ].…”

Seroepidemiological survey on chikungunya in endemic zones for arboviruses in Brazil, 2019

“…In Brazil, there are few seroprevalence studies. In a recent study conducted in the city of Juazeiro do Norte, Southern Ceará State, Brazil, the seroprevalence of CHIKV was 25.5% (Barreto et al, 2020). A survey carried out in 2015 in the city of Feira de Santana and Riachão do Jacuípe, both located in the state of Bahia, Brazil, resulted in a CHIKV seroprevalence of 51.0%.…”