RESUMEN
Hepatitis A virus (HAV) has shown intermediate endemicity in Argentina, but its incidence has decreased since vaccine introduction in 2005. Environmental surveillance was conducted in five rivers from Argentina from 2005 to 2012, complementing clinical information. HAV detection decreased since 2005, although its circulation continues, maintaining viral diversity but not undergoing antigenic drift. Most sequences belonged to subgenotype IA, closely related to Argentinean clinical sequences, but one belonged to proposed subgenotype IC, previously undetected in the country. Environmental surveillance might contribute to monitoring the single-dose vaccination schedule, representing not only strains causing disease but also the circulating population and the viral introductions.
Asunto(s)
Vacunas contra la Hepatitis A/administración & dosificación , Virus de la Hepatitis A/aislamiento & purificación , Hepatitis A/epidemiología , Adolescente , Adulto , Argentina/epidemiología , Niño , Preescolar , Femenino , Genotipo , Hepatitis A/virología , Humanos , Lactante , Masculino , Datos de Secuencia Molecular , ARN Viral/genética , Ríos/virología , Análisis de Secuencia de ADN , Adulto JovenRESUMEN
In the province of Salta, in the Northwest region of Argentina, almost two-thirds of the population live in absolute poverty, and diseases associated with poverty are rampant. Almost 12% of the total population of the province are children below 5 years of age; almost half of these infants are living in situations where the basic necessities are not available. Primitive sanitary conditions, including widespread contamination of available water supplies with pathogens, contribute to a major public health problem. Infant mortality was 17% higher for Salta than for Argentina as a whole in 2001. A major cause of death for these children is infectious disease, especially respiratory and intestinal diseases. In Salta, more than half of the total population of infants is affected by diarrhoea annually. The infectious pathogens are diverse: bacteria (predominantly in spring and summer), viruses (especially in the winter) and parasites (endemic in some situations). This paper evaluates current methods used to test for the presence of pathogens in drinking water; discusses why these methods are less than adequate; documents an episode of contamination in a local water supply source; and suggests appropriate methods that can be used to better address this major public health issue effectively.