RESUMEN
A previous surveillance study of human pathogens within ticks collected in the country of Georgia showed a relatively high infection rate for Rickettsia raoultii, R. slovaca, and R. aeschlimannii. These 3 spotted fever group rickettsiae are human pathogens: R. raoultii and R. slovaca cause tick-borne lymphadenopathy (TIBOLA), and R. aeschlimannii causes an infection characterized by fever and maculopapular rash. Three quantitative real-time polymerase chain reaction (qPCR) assays, Rraoul, Rslov, and Raesch were developed and optimized to detect R. raoultii, R. slovaca, and R. aeschlimannii, respectively, by targeting fragments of the outer membrane protein B gene (ompB) using species-specific molecular beacon or TaqMan probes. The 3 qPCR assays showed 100% specificity when tested against a rickettsiae DNA panel (n=20) and a bacteria DNA panel (n=12). The limit of detection was found to be at least 3 copies per reaction for all assays. Validation of the assays using previously investigated tick nucleic acid preparations, which included Rickettsia-free tick samples, tick samples that contain R. raoultii, R. slovaca, R. aeschlimannii, and other Rickettsia spp., gave 100% sensitivity for all 3 qPCR assays. In addition, a total of 65 tick nucleic acid preparations (representing 259 individual ticks) collected from the country of Georgia and the Republic of Azerbaijan in 2009 was tested using the 3 qPCR assays. R. raoultii, R. slovaca, and R. aeschlimannii were not detected in any ticks (n=31) from the Republic of Azerbaijan, but in the ticks from the country of Georgia (n=228) the minimal infection rate for R. raoultii and R. slovaca in Dermacentor marginatus was 10% and 4%, respectively, and for R. aeschlimannii in Haemaphysalis sulcata and Hyalomma spp. it was 1.9% and 20%, respectively.
Asunto(s)
Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Infecciones por Rickettsia/diagnóstico , Infecciones por Rickettsia/microbiología , Rickettsia/aislamiento & purificación , Animales , Azerbaiyán , Proteínas de la Membrana Bacteriana Externa/genética , ADN Bacteriano/genética , Dermacentor/microbiología , Georgia (República) , Humanos , Sondas de Oligonucleótidos/genética , Rickettsia/clasificación , Rickettsia/genética , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Infectious diseases present a potentially substantial yet undefined burden on the health of the adult Azerbaijani population. Efforts to quantify this burden in Azerbaijan are currently based almost exclusively on passive disease surveillance, and therefore hinge on the health utilization practices of the population. Understanding the prevalence of infectious syndromes and health utilization practices is paramount to disease surveillance, public health planning, and health care system reform. METHODS: A two-stage, probability proportional to size sampling design was used to select a representative sample of three regions of northern Azerbaijan with village populations less than 500 people. Demographic, clinical, and epidemiologic parameters were assessed using prevalence odds ratios, chi-squared, and the Fisher exact test. Associations with p < 0.10 were included in the regression analysis and removed by backward elimination. Respondents included 796 adults from 39 villages. RESULTS: Self-medication with antibiotics was the predominant utilization practice reported (19.4%). Only 1.3% of respondents reported seeing a health care provider for an infection, and 3.4% missed work or stayed in bed during the day in the last 5 years. In contrast, 338 illness episodes were reported in a 5 year period. Antibiotic use was significantly associated with gender, region, history of febrile illness, sleep disturbances, and arthritis controlling for age, ethnicity, and education. Influenza-like illness was the most prevalent infectious syndrome reported (33.3%). CONCLUSIONS: We observed a remarkably low utilization of health services, despite reported symptoms that would merit use. Widespread availability of antibiotics may deter health care use, and may contribute to the development of antibiotic resistance in this population. Information on utilization of health services during an infection is essential for development of effective intervention strategies, and data on the prevalence of infectious syndromes provides information not otherwise available in populations with low health care utilization.