Asunto(s)
Aves , Subtipo H5N1 del Virus de la Influenza A , Gripe Aviar/epidemiología , Gripe Humana/epidemiología , Enfermedades de las Aves de Corral/epidemiología , Animales , Asia/epidemiología , Humanos , Gripe Aviar/transmisión , Gripe Humana/transmisión , Gripe Humana/virología , Enfermedades de las Aves de Corral/transmisiónRESUMEN
An outbreak of Q fever occurred in South Wales, United Kingdom, from July 15 through September 30, 2002. To investigate the outbreak a cohort and nested case-control study of persons who had worked at a cardboard manufacturing plant was conducted. The cohort included 282 employees and subcontractors, of whom 253 (90%) provided blood samples and 214 (76%) completed questionnaires. Ninety-five cases of acute Q fever were identified. The epidemic curve and other data suggested an outbreak source likely occurred August 5-9, 2002. Employees in the factory's offices were at greatest risk for infection (odds ratio 3.46; 95% confidence interval 1.38-9.06). The offices were undergoing renovation work around the time of likely exposure and contained straw board that had repeatedly been drilled. The outbreak may have been caused by aerosolization of Coxiella burnetii spore-like forms during drilling into contaminated straw board.
Asunto(s)
Coxiella burnetii , Brotes de Enfermedades , Industrias , Exposición Profesional , Papel , Fiebre Q/epidemiología , Estudios de Casos y Controles , Coxiella burnetii/aislamiento & purificación , HumanosRESUMEN
A double-blind, community-randomized, placebo-controlled trial was conducted in a rural area of The Gambia between June and December 1999 to test whether a reduction in the infectious reservoir can reduce malaria transmission. Overall 14,017 (85%) individuals living in the study area were treated with either placebo or sulfadoxine-pyrimethamine (SP) combined with a single dose of artesunate (AS). Following the mass drug administration (MDA) 1375 children aged 6 months to 10 years were kept under surveillance for clinical malaria in 18 villages throughout the 1999 malaria transmission season. During a 20-week surveillance period 637 episodes of malaria were detected. The mean incidence rate was 2.5/100 child-weeks in the placebo villages, and 2.3/100 child-weeks in villages that received SP + AS. The mean rate ratio, adjusted for individual and village-level covariates, was 0.91 (95% CI 0.68-1.22, P = 0.49). During the first 2 months of surveillance, the malaria incidence was lower in treated villages. After 2 months the incidence was slightly higher in the MDA group but this was not statistically significant. Overall, no benefit of the MDA could be detected. The reason for the absence of an impact on malaria transmission is probably the very high basic reproductive number of malaria, and the persistence of mature gametocytes, which are not affected by AS treatment.