ABSTRACT
Tick borne encephalitis (TBE) is endemic to eastern and central Europe with broad temporal and spatial variation in infection risk. Although many studies have focused on understanding the environmental and socio-economic factors affecting exposure of humans to TBE, comparatively little research has been devoted to assessing the underlying ecological mechanisms of TBE occurrence in enzootic cycles, and therefore TBE hazard. The aim of this study was to evaluate the effect of the main ungulate tick hosts on the pattern of tick infestation in rodents and TBE occurrence in rodents and questing adult ticks. In this empirical study, we considered three areas where endemic human TBE occurs and three control sites having no reported human TBE cases. In these six sites located in Italy and Slovakia, we assessed deer density using the pellet group count-plot sampling technique, collected questing ticks, live-trapped rodents (primarily Apodemus flavicollis and Myodes glareolus) and counted ticks feeding on rodents. Both rodents and questing ticks were screened for TBE infection. TBE infection in ticks and rodents was positively associated with the number of co-feeding ticks on rodents and negatively correlated with deer density. We hypothesise that the negative relationship between deer density and TBE occurrence on a local scale (defined by the minimum overlapping area of host species) could be attributed to deer (incompetent hosts) diverting questing ticks from rodents (competent hosts), know as the 'dilution effect hypothesis'. We observed that, after an initial increase, the number of ticks feeding on rodents reached a peak for an intermediate value of estimated deer density and then decreased. Therefore, while at a regional scale, tick host availability has already been shown to be directly correlated with TBE distribution, our results suggest that the interactions between deer, rodents and ticks are much more complex on a local scale, supporting the possibility of a dilution effect for TBE.
Subject(s)
Deer/parasitology , Encephalitis Viruses, Tick-Borne/isolation & purification , Ixodes/growth & development , Rodent Diseases/epidemiology , Tick Infestations/veterinary , Animals , Ecosystem , Italy , Ixodes/virology , Population Density , Rodent Diseases/parasitology , Rodentia , Slovakia , Tick Infestations/epidemiology , Tick Infestations/parasitologyABSTRACT
OBJECTIVES: To evaluate the diagnostic value of the Pap smear in lower genital tract infections during pregnancy. MATERIALS AND METHODS: A total of 190 pregnant women were examined in the Lower Genital Tract and Colposcopy clinics of the Obstetrics Division at the University Hospital de Clínicas "José de San Martín" of University of Buenos Aires from April to August 1997. Samples were taken from the vaginal fornix for microbiologic study and from the exocervix for Pap smear. Both the sensitivity and specificity test of the Pap smear for diagnosing lower genital tract infections were calculated considering the microbiologic study as the reference standard. RESULTS: The sensitivity of the Pap smear for Candida spp., bacterial vaginosis and Trichomonas vaginalis compared with microbiologic study was 50, 81, and 78, respectively. The specificity for the same study was 96%, 93%, and 100%, respectively. CONCLUSIONS: Pap smear for diagnosing lower genital tract infections is useful when positive results are found for these infections because of its high specificity.
ABSTRACT
La nueva imagenología mamaria ha descubierto un grupo de lesiones no palpables que puede alcanzar hasta el treinta por ciento de los casos examinados
Subject(s)
Humans , Female , Biopsy , Biopsy, Needle/instrumentation , Breast Neoplasms/pathology , Breast/cytology , Needles/statistics & numerical dataABSTRACT
La nueva imagenología mamaria ha descubierto un grupo de lesiones no palpables que puede alcanzar hasta el treinta por ciento de los casos examinados
