中国20个省、区、市动物莱姆病初步调查研究

目的：广泛调查我国动物莱姆病分布情况。方法：血清流行病学和病原学研究。结果：１９８７～１９９７年间，牛、羊、狗、野兔和８种野鼠有莱姆病的感染存在，其中牛、羊、狗和野鼠的感染率分别为１８．１８％～３２．６１％、１７．１２％～６１．２１％、３８．５％～６０．００％和４１．１８％～８６．０５％；从黑线姬鼠和白腹巨鼠的胎鼠分离到莱姆病螺旋体，证实莱姆病螺旋体可通过胎盘垂直传播。９种蜱的中肠携带莱姆病螺旋体，带菌率以全沟硬蜱、二棘血蜱和粒形硬蜱为高，分别为２０．００％～４５．００％、１６．００％～４０．００％和２４．００％。从华南兔、８种野鼠和８种蜱分离出１２８株莱姆病螺旋体。证实黑线姬鼠和棕背是中国莱姆病螺旋体的重要储存宿主；多种蜱的中肠内携带莱姆病螺旋体，我国北方林区莱姆病螺旋体的主要生物媒介是全沟硬蜱，南方林区二棘血蜱和粒形硬蜱是重要的生物媒介。结论：我国动物莱姆病广泛存在     

Anaplasma phagocytophilum, Babesia microti, and Borrelia burgdorferi in Ixodes scapularis, southern coastal Maine

Ixodes scapularis (deer ticks) from Maine were tested for multiple infections by polymerase chain reaction and immunofluorescence. In 1995, 29.5%, 9.5%, and 1.9% of deer ticks were infected with Borrelia burgdorferi, Anaplasma phagocytophilum, and Babesia microti, respectively. In 1996 and 1997, the number of A. phagocytophilum-infected ticks markedly declined. In 1995 through 1996, 4 (1.3%) of 301 were co-infected.     

Infections with Tickborne Pathogens after Tick Bite,Austria, 2015–2018

The aim of this prospective study was to assess the risk for tickborne infections after a tick bite. A total of 489 persons bitten by 1,295 ticks were assessed for occurrence of infections with Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, Rickettsia spp., Babesia spp., Candidatus Neoehrlichia mikurensis, and relapsing fever borreliae. B. burgdorferi s.l. infection was found in 25 (5.1%) participants, of whom 15 had erythema migrans. Eleven (2.3%) participants were positive by PCR for Candidatus N. mikurensis. One asymptomatic participant infected with B. miyamotoi was identified. Full engorgement of the tick (odds ratio 9.52) and confirmation of B. burgdorferi s.l. in the tick by PCR (odds ratio 4.39) increased the risk for infection. Rickettsia helvetica was highly abundant in ticks but not pathogenic to humans. Knowledge about the outcome of tick bites is crucial because infections with emerging pathogens might be underestimated because of limited laboratory facilities.     

Tick-borne Agents in Rodents, China, 2004�C2006

A total of 705 rodents from 6 provinces and autonomous regions of mainland People’s Republic of China were tested by PCRs for tick-borne agents (Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato, spotted fever group rickettsiae, and Francisella tularensis). Infection rates were 5.5%, 6.7%, 9.1% and 5.0%, respectively. Eighteen (2.6%) rodents of 10 species were positive for 2 or 3 agents. Sequence analysis of PCR products confirmed the presence and genotypes of detected agents. These findings demonstrate that these tick-borne agents cocirculate and that a variety of rodent species may be involved in their enzootic maintenance.     

Correlation between Tick Density and Pathogen Endemicity, New Hampshire

To assess the endemicity of tick-borne pathogens in New Hampshire, we surveyed adult tick vectors. Pathogens were more prevalent in areas of high tick density, suggesting a correlation between tick establishment and pathogen endemicity. Infection rates in ticks correlated with disease frequency in humans.     

Infections with Candidatus Neoehrlichia mikurensis and Cytokine Responses in 2 Persons Bitten by Ticks,Sweden

The prevalence of Candidatus Neoehrlichia mikurensis infection was determined in 102 persons bitten by ticks in Sweden. Two infected women had erythematous rashes; 1 was co-infected with a Borrelia sp., and the other showed seroconversion for Anaplasma phagocytophilum. Both patients had increased levels of Neoehrlichia DNA and serum cytokines for several months.