RESUMO
The phylum Apicomplexa comprises intracellular protozoa that include many human pathogens. Their nearest relatives are chromerids and colpodellids. We report a case of a Babesia spp.-like relapsing infection caused by a newly described microorganism related to the Apicomplexa. This case is highly suggestive of a previously undescribed type of colpodellid that infects vertebrates.
Assuntos
Apicomplexa/isolamento & purificação , Anti-Infecciosos/uso terapêutico , Apicomplexa/classificação , Apicomplexa/genética , Artemeter , Artemisininas/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Filogenia , RNA Ribossômico 18S/genética , Tetraciclina/uso terapêuticoRESUMO
OBJECTIVE: To determine the prevalence of Mycoplasma suis infection in swine, swine-farm workers, and swine veterinarians in Shanghai, China. SAMPLE POPULATION: 172 swine and 65 workers and veterinarians from 19 commercial swine farms. PROCEDURES: Blood samples were collected from all study subjects. Blood samples were examined for the presence of M suis by means of compound and scanning electron microscopy. A species-specific PCR assay was developed for detection of M suis DNA extracted from blood samples. Relationships between infection status of swine and sex, age, geographic location, and clinical signs of disease were evaluated by use of a C(2) test. The phylogenetic relationship between partial 16S ribosomal RNA (rRNA) sequences from swine and human isolates of M suis was determined. RESULTS: 86% (148/172) of swine and 49% (32/65) of humans had positive PCR assay results for M suis infection. Swine infection status was not associated with any variable, with the exception of pyrexia and subcutaneous bleeding. The partial 16S rRNA sequences from human and swine isolates of M suis were 98% homologous and in the same phylogenetic cluster as a previously identified swine isolate of M suis. CONCLUSIONS AND CLINICAL RELEVANCE: A large proportion of swine and humans in close contact with those swine were infected with M suis in Shanghai, China. The close phylogenetic relationship between swine and human isolates of M suis suggested possible interspecies transmission; however, additional research is required to better assess that possibility.