Disseminated Histoplasmosis Seasonal Incidence Variations: A Supplementary Argument for Recent Infection?

Abstract

International audienceBackground: In French Guiana, a recent study has shown that a major part of the histoplasmosis incidence temporal fluctuations could be explained by climatic factors and thus postulated that disseminated histoplasmosis cases could be in a large proportion due to new infections. The description of the seasonal pattern of histoplasmosis could potentially help to test this new hypothesis. Patients and methods: A study using prospective data from the French Hospital Database for HIV was conducted in order to determine seasonal variations of the incidence of first cases of disseminated histoplasmosis in HIV persons in Cayenne, French Guiana. Single failure Cox proportional hazards models were used. Results: After adjusting for CD4 counts and antiretroviral treatment, the incidence of disseminated histoplasmosis was significantly higher during the Short Wet Season-Long Dry Season than during the Short Dry Season-Long Wet Season (Adjusted Hazard ratio 1.7 (1.1-2.5), P= 0.01). Conclusion: This result gives both valuable epidemiologic information to clinicians and a supplementary argument in favour of the hypothesis that an important proportion of cases were due to recent exposure. Therefore, the use of a primary prophylaxis must be discussed in French Guiana

Hospitalisations for mycoses as an indicator of socio‐environmental vulnerability in the Brazilian Amazon‐Savanna transition region

“…32 The ideal conditions for the development of Histoplasma capsulatum and its subsequent dispersion in the environment can be favoured by climatic variables, and the higher incidence of histoplasmosis in HIV patients can be significantly associated to seasonal cycles. 33 Our data support several studies that affirm the strong influence of rain on the incidence of mycoses. 6,7,14,30,31,34,35 Climatic variables, such as precipitation and temperature, are known to affect the incidence of coccidioidomycosis.…”

“…The decreasing maximum temperature is an environmental factor that can be associated to a high‐risk to hospitalisation owing to blastomycosis . The ideal conditions for the development of Histoplasma capsulatum and its subsequent dispersion in the environment can be favoured by climatic variables, and the higher incidence of histoplasmosis in HIV patients can be significantly associated to seasonal cycles …”

Typical Facial Lesions: A Window of Suspicion for Progressive Disseminated Histoplasmosis—A Case of Asian Prototype

“…Further, his residence was close to Ganges belt from where cases of Histoplasma have been reported frequently [ 6 ]. There are not many studies to prove seasonal variation, but one French study showed a peak of infection during a long dry season [ 9 ]. Similar to our case that has been symptomatic in July 2014, there was another case presented in July 2012 as reported from Southern India [ 10 ].…”

Primary or secondary prevention of HIV-associated histoplasmosis during the early antiretrovirals for all era

“…In a cohort of HIV-infected persons living in endemic French Guiana, where the prevalence of positive skin tests is around 30%, we found that the incidence rate of disseminated histoplasmosis increased sharply as CD4 counts dropped below 100 per μL exceeding 10 per 100 person years, with a significant seasonal effect and a risk difference of 0.7 per 100 person years between dry and wet seasons [ 7 , 8 ]; the attributable risk percent in the overall HIV cohort (61%) implies that, overall, 61% of cases were attributable to the dry season and, arguably, to newly acquired infections. Hence, for patients in our HIV cohort, and presumably most cohorts in endemic Latin America [ 9 ], there is regular exposure to a major pathogen for most patients and thus possibility of prevention of infection and dissemination.…”