Low seroprevalence of Zika virus in Cameroonian blood donors

Abstract

A Zika virus seroepidemiology study was performed in 1084 blood donors collected from August to October 2015 in six sites of Cameroon representing a large panel of eco-environments. Samples were tested using an anti-NS1 IgG ELISA detection kit and positives were further confirmed by seroneutralization. The observed global seroprevalence was low (around 5%, peaking at 10% and 7.7% in Douala and Bertoua, respectively) with risk factors associated with seropositivity pointing to the existence of a local (peri-)sylvatic cycle of transmission. These results call attention to the potential introduction and subsequent spread in African urban areas of Asian genotype Zika virus currently circulating in the Americas and adapted to transmission by peri-domestic mosquitoes. They should leverage reinforced surveillance efforts in Africa.

Zika virus seroprevalence in blood donors from the Northeastern region of São Paulo State, Brazil, between 2015 and 2017

“…In Bolivia the ZIKV seroprevalence among blood donors was 39.0% in Beni and 25.1% in Santa Cruz departments, 20 in Suriname it was 35.1% 21 (urban and rural population), in Nicaragua: 36.1%, 45.8% and 56.4% in pediatric, household and adult cohorts 22 respectively, while in Northeast Brazil (63.3%) (total ZIKV seroprevalence for HIV-infected, tuberculosis patients and pregnant women). 23 On the other hand, in other regions of the world the ZIKV seroprevalence among blood donors was lower or similar to our results, examples being Rwanda (1.4%) 24 , Cameroon (5%) 25 and Laos (4.5 −9.9%). 26 The difference in ZIKV seroprevalence can be explained on one Our study demonstrated a significant difference between the obtained ZIKV seroprevalence by ELISA and PRNT tests.…”

High Zika Virus Seroprevalence in Salvador, Northeastern Brazil Limits the Potential for Further Outbreaks

“…However, the majority of studies aiming at test validation investigated patients with acute febrile illness and included only a few or no sera from individuals living in areas where DENV is endemic, limiting the ability to extrapolate results from those studies to our study population. Recent studies investigating asymptomatic blood donors from Martinique and Cameroon suggested applicability of the NS1-based ELISA, despite a high DENV burden in these areas ( 45 , 46 ). Furthermore, our NS1-based ELISA results were largely congruent with PRNT-based analyses conducted within subpopulations.…”

Different populations of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) from Central Africa are susceptible to Zika virus infection

“…In Central Africa, ZIKV circulation in human populations was confirmed in Cameroon, Central African Republic (CAR), and Gabon [18]. As an example, in Cameroon, 2 to 10% blood donors were ZIKV-positive [27]. In Central Africa, exposure to ZIKV has also been confirmed in animals, monkeys and bats [18], and ZIKV was detected in two mosquito species in CAR (Ae.…”

“…aegypti has never been found naturally infected with ZIKV in the Central African region. However, from a study with blood donors showing that ZIKV is circulating in Cameroon, nearly 5-10% of people from six towns have been exposed to ZIKV infections [27]. The vector competence of natural Aedes populations from Central Africa has remained unclear.…”