High prevalence of malaria infection in Amazonas state, Venezuela Incidencia de malaria en una región endémica del estado Amazonas, Venezuela

• Published in: Revista do Instituto de Medicina Tropical de São Paulo
• Main Authors: Hectorina Rodulfo, Marcos de Donato, Isaurea Quijada, Ada Peña
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidade de São Paulo (USP) 2007
• Subjects: Epidemiology; Malaria; PCR; P. falciparum; P. vivax; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic; Azar; San Fernando
• Online Access: https://doi.org/10.1590/S0036-46652007000200003; https://doaj.org/article/e6ec9a42391c4606bed63f9ab17689ea

This study was carried out to determine the incidence of malaria in an endemic region of Amazonas State, Venezuela. For this, 200 random samples were collected from symptomatic and asymptomatic individuals from San Fernando de Atabapo and Santa Barbara. Epidemiological factors were related to malaria infection, which was diagnosed by microscopy observation and amplification of the 18S rDNA sequence by PCR. Malaria prevalence in these populations was 28.5%, whilst P. vivax and P. falciparum prevalences were 12 and 17%, respectively. No infection by P. malariae was found. A mixed infection was found on an asymptomatic individual. Prevalence patterns differed between age groups depending on the Plasmodium species. We found that 34.8% of the P. vivax and 15.2% of the P. falciparum infections were asymptomatic. The use of nets was helpful to prevent P. vivax infection, but did not protect against P. falciparum infection. The results suggest the presence of more than one mosquito vector in the area, displaying a differential pattern of infection for each Plasmodium species. There appear to be risk factors associated with malaria infections in some individuals. The population based approach and PCR diagnosis improved the accuracy of the statistical analysis in the study. Este estudio fue llevado a cabo para determinar la incidencia de malaria en una región endémica del estado Amazonas, Venezuela. Doscientas muestras tomadas al azar fueron colectadas de individuos sintomáticos y asintomáticos de San Fernando de Atabapo y Santa Bárbara. Factores epidemiológicos fueron relacionados con la infección de malaria, diagnosticada por observación microscópica y por la amplificación por PCR de la secuencia del ADNr 18S. La prevalencia de malaria en estas poblaciones fue 28.5%, en tanto que las prevalencias para P. vivax y P. falciparum fueron 12 y 17%, respectivamente. No se encontró infección por P. malariae. Se encontró una infección mixta en un individuo asintomático. Los patrones de prevalencia difirieron entre los grupos de ...