Detección de virus entéricos en un sistema piloto de tratamiento de aguas residuales municipales / Detection of Enteric Viruses in a Pilot System for Municipal Wastewater Treatment

Se evaluó un sistema piloto de tratamiento de aguas residuales municipales para verificar su capacidad de remoción de patógenos virales. La presencia de Adenovirus, Calicivirus, Enterovirus, Virus de Hepatitis A y Virus de Hepatitis E. Se determinó mediante RT-PCR (Reacción en Cadena de la Polimerasa con Transcriptasa Reversa). Además se examinó la eficacia de los colifagos como indicadores y se verificó la presencia de indicadores bacterianos clásicos. Se obtuvo un 100% de positividad para la presencia de todos los virus en la entrada y salida del sistema, por lo que el sistema no es capaz de eliminarlos. Los colifagos no fueron removidos por este sistema, pero sirvieron como indicadores para la presencia de virus entéricos en el mismo. Los indicadores bacterianos redujeron su número a su paso por el sistema, pero aún al final del sistema, los coliformes se encontraban en números por encima de los límites establecidos por las leyes venezolanas. Por lo tanto, sería necesario agregar otros pasos al sistema, para poder obtener un efluente que cumpla las leyes y que garantice la ausencia de virus entéricos.

A pilot system for treating municipal waste was evaluated to verify its ability to remove viral pathogens. The presence of Adenovirus, Calicivirus, Enterovirus and Hepatitis A and E was determined using RT-PCR. The efficiency of coliphages as indicators and the presence of classic bacterial indicators were also investigated. A 100% positivity was obtained for the presence of all viruses at the entrance and exit of the system; therefore, the system was not able to remove them. Coliphages weren’t removed by the system, but they were effective as indicators of enteric viral presence in it. Bacterial indicators reduced their number going through the system, but even at the end of the system, coliforms had numbers above the limits dictated by Venezuelan law. Therefore, it would be necessary to add additional steps to the system in order to obtain an effluent that meets the laws and to ensure the absence of enteric viruses.

Seroepidemiología de la toxoplasmosis en una comunidad indígena Yucpa de la Sierra de Perijá, Estado Zulia, Venezuela / Seroepidemiology of toxoplasmosis in a Yucpa Amerindian community of Sierra de Perijá, Zulia State, Venezuela

BACKGROUND: There is a high rate of Toxoplasma gondii infection worldwide. In Latin America the rate is as high as 65% in some populations. AIM: To measure the prevalence of antibodies against Toxoplasma gondii in a native Yucpa community in Venezuela. SUBJECTS AND METHOD: Total serum antibodies measured by indirect hemagglutination and IgM antibodies by ELISA were measured in 94 Yucpa subjects (49 males), aged from 3 months to 100 years. RESULTS: The overall prevalence of infection was 63%. Fifty nine subjects had total antibodies and 14 had IgM antibodies. No significant differences by age or sex, were observed in the proportion of subjects with positive total or IgM antibodies. CONCLUSIONS: The studied individuals had a high prevalence of Toxoplasma gondii infection.

[Seroepidemiology of toxoplasmosis in a marginal community of the Municipality of Maracaibo, Zulia State, Venezuela]. / Seroepidemiología de la toxoplasmosis en una comunidad marginal del Municipio Maracaibo, Estado Zulia, Venezuela.

The goal of this study was to determine the prevalence of anti-Toxoplasma gondii antibodies in a marginal community of the Municipality of Maracaibo, Zulia State, Venezuela and if there was a relationship between risk factors and infection. An epidemiological survey of personal data, living sanitary conditions and contact with cats was performed. A collection of 254 blood samples from male and female individuals, with ages ranging from 8 months to 76 years, was studied. Anti-Toxoplasma gondii reaction was determined by indirect hemaglutination using a commercial kit. A positive reaction at a dilution > or = 1:64 was considered positive. Statistical analysis was performed using the Chi-squared test. The prevalence of infection was found to be 36.6%. It was observed that 21.5% of the seropositive presented titers not considered significant (< or = 1:64), 51.6% had intermediate titers (1:128 to 1:512), 24.8% high titers (1:1024 to 1:4096) and 2.1% very high titers (> or = 1:8192). The highest percentage of positivity (50%) was observed in the group > or = 46 years of age. No statistically significant association was observed between prevalence and risk factors (living together with cats and poor sanitary conditions of living) or infection when the chi-square test was used. Toxoplasma gondii infection was often found in the community of Puerto Caballo and probably cats and poor living conditions have a role in the transmission of infection.