Risk factors for dengue infection during the 1997 Cuban epidemic

Because no vaccine and no specific treatment exist for dengue virus infection, Aedes aegypti control is the only way to reduce the incidence of dengue. Its eradication is unlikely in the near future; Consequently, dengue control will depend on integrating mosquito vector management and directing efforts towards areas at higher risk for dengue transmission. In the past few years, little research has been conducted to identify those factors increasing the risk for dengue, particularly, individual practices and household factors. Their analysis is essential to implement dengue control strategies, since most of the infections occur at home and are determined by human behavior. We therefore, conducted a case control study evaluating these factors during a dengue epidemic in Santiago de Cuba in 1997.; The study included 350 laboratory confirmed recently infected dengue cases and 350 controls aged 15 years or older, who were residents of the 1 to 4 Santiago de Cuba districts with the highest transmission during the 1997 epidemic. Data were collected through face to face interviews. 97 percent of eligible cases and 95 percent of a first and 92 percent of a second serosurvey of eligible controls were interviewed.; The study results are presented in two manuscripts. In the first, positive adjusted associations were observed between dengue and: presence in the premise of containers of small/medium capacities (200 L or less) and large capacity (more than 200 L); place of the water filled container inside the home and both, inside and outside of the home; water replacement with container interval between cleaning longer than a week; presence of animal water pans, religious and/or flower vases and a mixture of several potential breeding sites in the premises, another dengue case at home and in the neighborhood, and low perception that the household conditions were supportive for Aedes aegypti or dengue risk. A highly significant linear trend was detected for categories of risk perception (Trend test: p < 0.001).; In the second paper negative adjusted associations were found between dengue and: use of inside home insecticide sprays several times per week or every day, burning herbs inside home every day during day and night, use of air conditioner and/or fan day and night; and, self perception about the need for protection against dengue infection.; In addition, using logistic regression the authors found the determinants of the Santiago epidemic. The factors independently (p < 0.05) and positively associated with dengue infection during the 1997 Cuban epidemic were: Educational level 13 years or more, spending daytime at home, presence in the premise of containers of both capacities, less than 200 L or less and more than 200 L, water replacement with container cleaning at intervals longer than a week, presence of animal water pans and a mixture of different potential breeding site types at home, other dengue cases at home or in the neighborhood and self perception of dengue risk. The factors negatively associated were: Use of fan and/or air conditioners day and night and self-perception of the degree of protection they had during the epidemic. The self-perception variables had highly significant linear trend tests with categories of perception.