Aspects cliniques et biologiques des arboviroses

Risk factors for Zaire ebolavirus--specific IgG in rural Gabonese populations

BACKGROUND

In Gabon, several Ebolavirus outbreaks have occurred exclusively in the northeastern region. We conducted a large serosurvey to identify areas and populations at risk and potential demographic, clinical, and behavioral risk factors.

METHODS

Blood samples and clinical and sociodemographic data were collected from 4349 adults and 362 children in a random sample of 220 villages in the 9 provinces of Gabon. An enzyme-linked immunosorbent assay was used to detect Zaire ebolavirus (ZEBOV)-specific IgG, and thin blood smears were used to detect parasites. Logistic regression was implemented using Stata software (Stata), and a probability level of <.05 was considered to be statistically significant.

RESULTS

The prevalence of ZEBOV-specific IgG was 15.3% overall, increasing to 32.4% (P< .001) in forest areas. No sociodemographic risk factors were found, but the antibody prevalence increased linearly up to 20 years of age. Chronic arthralgia and amicrofilaremia were the only factors associated with ZEBOV seropositivity.

CONCLUSIONS

These findings confirm the endemicity of ZEBOV in Gabon and its link to the ecosystem. Human antibody positivity would appear to be to the result of exposure to contaminated fruits.

Chikungunya : un syndrome algo-éruptif fébrile au retour de l’Océan Indien

A 40-year-old woman presented with invalidating polyarthritis associated with high fever and diffuse macular exanthema after returning from a two-week visit to Reunion Island. In this paper, we discuss the different diagnoses to be considered in a case of fever with pain and rash and we examine the epidemiology, clinical features, diagnostic methods and management of Chikungunya virus.