RESUMO
We collected fecal samples from 21 individuals infected with Taenia tapeworms in Koh Kong Province, Cambodia, and performed nucleotide sequencing of the cox1 gene and multiplex PCR on the eggs for DNA differential diagnosis of human Taenia tapeworms. Genomic DNA was extracted from the eggs of a minimum number of 10 isolated from fecal samples. Using oligonucleotide primers Ta7126F, Ts7313F, Tso7466F, and Rev7915, the multiplex PCR assay proved useful for differentially diagnosing Taenia solium, Taenia saginata, and Taenia asiatica based on 706, 629, and 474 bp bands, respectively. All of the Taenia specimens from Kho Kong, Cambodia, were identified as either T. saginata (n=19) or T. solium (n=2) by cox1 sequencing and multiplex PCR.
Assuntos
Adolescente , Adulto , Animais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Camboja , Ciclo-Oxigenase 1/genética , Primers do DNA/genética , DNA de Helmintos/química , Fezes/parasitologia , Proteínas de Helminto/genética , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Taenia saginata/enzimologia , Taenia solium/enzimologia , Teníase/parasitologiaRESUMO
Species identification of Taenia tapeworms was performed using morphologic observations and multiplex PCR and DNA sequencing of the mitochondrial cox1 gene. In 2008 and 2009, a total of 1,057 fecal samples were collected from residents of Kongwa district of Dodoma region, Tanzania, and examined microscopically for helminth eggs and proglottids. Of these, 4 Taenia egg positive cases were identified, and the eggs were subjected to DNA analysis. Several proglottids of Taenia solium were recovered from 1 of the 4 cases. This established that the species were T. solium (n=1) and T. saginata (n=3). One further T. solium specimen was found among 128 fecal samples collected from Mbulu district in Arusha, and this had an intact strobila with the scolex. Phylegenetic analysis of the mtDNA cox1 gene sequences of these 5 isolates showed that T. saginata was basal to the T. solium clade. The mitochondrial cox1 gene sequences of 3 of these Tanzanian isolates showed 99% similarity to T. saginata, and the other 2 isolates showed 100% similarity to T. solium. The present study has shown that Taenia tapeworms are endemic in Kongwa district of Tanzania, as well as in a previously identified Mbulu district. Both T. solium isolates were found to have an "African/Latin American" genotype (cox1).