Isolation of a Rochalimaea-like organism from a febrile patient infected with human immunodeficiency virus was confirmed. Analysis of 16S rRNA gene sequences, together with polymerase chain reaction and restriction endonuclease length polymorphism analysis of a portion of the citrate synthase gene, demonstrated that the agent is closely related to members of the genus Rochalimaea and that the isolate is genotypically identical to the presumptive etiologic agent of bacillary angiomatosis. However, the same genotypic analyses readily differentiated the new isolate from isolates of other recognized Rochalimaea species as well as other genera of bacteria previously suggested as putative etiologic agents of bacillary angiomatosis and related syndromes. We propose that the novel species be referred to as Rochalimaea henselae sp. now.

No abstract

Bartonella species were isolated from the blood of 63 of 325 Rattus norvegicus and 11 of 92 Rattus rattus from 13 sites in the United States and Portugal. Infection in both Rattus species ranged from 0% (e.g., 0/87) to approximately 60% (e.g., 35/62). A 337-bp fragment of the citrate synthase (gltA) gene amplified by polymerase chain reaction was sequenced from all 74 isolates. Isolates from R. norvegicus were most similar to Bartonella elizabethae, isolated previously from a patient with endocarditis (93%-100% sequence similarity), followed by Bartonella grahamii and other Bartonella species isolated from Old World rodents (Clethrionomys species, Mus musculus, and Rattus species). These data suggest that Rattus species are a reservoir host for pathogenic Bartonella species and are consistent with a hypothesized Old World origin for Bartonella species recovered from Rattus species introduced into the Americas.

The bacterial 16S rRNA genes from blood samples of two patients with human ehrlichiosis and from an isolate recovered from one of the patients were amplified by using the polymerase chain reaction. The amplimers were then cloned and sequenced. The 16S rRNA gene sequence was also determined for Ehrlichia canis (two strains), E. equi, E. phagocytophila (two strains), and E. sennetsu (two strains). These sequences, along with a previously published 16S rRNA gene sequence of E. risticii, were compared. The 16S rRNA gene sequences were identical for all three sources of the human ehrlichiosis agent. The sequence comparisons indicate that the human ehrlichiosis agent is a new species most closely related to E. canis (98.2%) and more distantly related to other Ehrlichia spp. We propose that this species be named Ehrlichia chaffeensis sp. nov., with the Arkansas strain as the type strain.

Objective Human papillomavirus (HPV) is a common sexually transmitted agent that causes anogenital cancer and precancer lesions that have an inflammatory infiltrate, may be friable and bleed. Our aim was to determine the association between anal HPV infection and HIV acquisition. Design A prospective cohort study. Methods We recruited 1409 HIV-negative men who have sex with men recruited from a community-based setting in Boston, Denver, New York and San Francisco. We used Cox proportional hazards regression modeling and assessed the independent association of HPV infection with the rate of acquisition of HIV infection. Results Of 1409 participants contributing 4375 person-years of follow-up, 51 HIV-seroconverted. The median number of HPV types in HPV-infected HIV-seroconverters was 2 (interquartile range 1–3) at the time of HIV seroconversion. After adjustment for sexual activity, substance use, occurrence of other sexually transmitted infections and demographic variables, there was evidence (P░=░0.002) for the effect of infection with at least two HPV types (hazard ratio 3.5, 95% confidence interval 1.2–10.6) in HIV seroconversion. Conclusion Anal HPV infection is independently associated with HIV acquisition. Studies that incorporate high-resolution anoscopy to more accurately identify HPV-associated disease are needed to determine the relationship between HPV-associated disease and HIV seroconversion.