House-level risk factors for triatomine infestation in Colombia.

BACKGROUND: Chagas disease, transmitted domestically by triatomine bugs, is the most important vector-borne disease in Latin America. The association between triatomine infestation and housing characteristics was investigated based on a standardized survey in 41 971 houses in 15 Departments in Colombia. METHODS: Multivariate logistic regression was used to test for associations of two highly correlated infestation measures of infestation (householders reporting having seen triatomines inside the house, and sending triatomines to the survey team), with 15 household-level risk factors. Risks were measured relative to a reference category of houses with up to three inhabitants, area up to 50 m(2), unplastered adobe walls, thatch roof and no outbuildings or domestic animals. RESULTS: The probability of seeing triatomines was highest for households with over seven inhabitants (OR = 1.24, 95% CI 1.11-1.39), overhead storage space (OR = 1.16, 95% CI 1.03-1.32), grain shed (OR = 1.25, 95% CI 1.02-1.52), cats (OR = 1.27, 95% CI 1.14-1.42) and pigs (OR = 1.16, 95% CI 1.03-1.30). Lowest risks were in houses with wooden walls (OR = 0.46, 95% CI 0.34-0.61), fully plastered walls (OR = 0.78, 95% CI 0.68-0.88), roofs made of tiles (OR = 0.51, 95% CI 0.33-0.78) and flagstone floors (OR = 0.57, 95% CI 0.42-0.76). Results for householders returning triatomines support this set of risk factors, but with wider confidence intervals. CONCLUSIONS: Surveillance of a few easily assessed household characteristics provides an accurate, rapid assessment of house-level variation in risk. Measured effect sizes for specific structural characteristics could be used to maximize the cost-effectiveness of programmes to reduce vector infestation and interrupt Chagas disease transmission by improving house quality

An Outbreak of Dengue Fever in St. Croix (US Virgin Islands), 2005

BACKGROUND: Periodic outbreaks of dengue fever occur in the United States Virgin Islands. In June 2005, an outbreak of dengue virus (DENV) serotype-2 with cases of dengue hemorrhagic fever (DHF) was detected in St. Croix, US Virgin Islands. The objective of this report is to describe this outbreak of DENV-2 and the findings of a case-control study examining risk factors for DHF. METHODOLOGY/PRINCIPAL FINDINGS: This is the largest dengue outbreak ever recorded in St. Croix, with 331 suspected dengue cases reported island-wide during 2005 (62.2 cases/10,000 population); 54% were hospitalized, 21% had at least one hemorrhagic manifestation, 28% had thrombocytopenia, 5% had DHF and 1 patient died. Eighty-nine laboratory-positive hospitalized patients were identified. Of these, there were 15 (17%) who met the WHO criteria for DHF (cases) and 74 (83%) who did not (controls). The only variable significantly associated with DHF on bivariate or multivariable analysis was age, with an adjusted odds ratio (95% confidence interval) of 1.033 (1.003,1.064). CONCLUSIONS/SIGNIFICANCE: During this outbreak of DENV-2, a high proportion of cases developed DHF and increasing age was significantly associated with DHF

Serum Proteome and Cytokine Analysis in a Longitudinal Cohort of Adults with Primary Dengue Infection Reveals Predictive Markers of DHF

10.1371/journal.pntd.0001887PLoS Neglected Tropical Diseases611

Frequency and clinical features of dengue infection in a schoolchildren cohort from medellin, Colombia.

To determine the incidence of dengue infection, we established active surveillance of febrile episodes in a cohort of schoolchildren from three schools in Medellin, Colombia. We followed a cohort of 2,379 schoolchildren in 2010 and followed 1,840 of these children the following year. During the follow-up time, 264 schoolchildren displayed 297 febrile episodes; of these, 23 episodes (7.7%) were caused by acute dengue infection. All four dengue serotypes were found, and all of the cases were mild. The most common symptoms in the dengue cases compared with those in other febrile illness were asthenia (96% versus 87%), anorexia (78% versus 57%), rhinorrhea (65.2% versus 58%), abdominal pain (56.5% versus 47.8%), arthralgia (43% versus 33%), and positive tourniquet test (13% versus 3%). This difference was not statistically significant. Pulse was elevated, and systolic arterial pressure was lower in dengue cases compared with other febrile illness (P 0.05). Mosquito indexes were determined in 8 children's houses and in the schools. Aedes aegypti adults were found in both households and in schools, whereas Aedes aegypti larvae were found only in schools. These results showed an elevated dengue frequency in children, with symptoms similar to those of other febrile illness and transmission risk in households and [email protected]