Epidemiological characteristics of Blastocystis hominis in urban region, southwestern China
ZHANG Shun-xian, TIAN Li-guang, LU Yan, LI Lan-hua, CHEN Jia-xu, ZHOU Xiao-nong
National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention; Key Laboratory for Parasitology and Vector Biology, MOH of China; WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai 200025, China
Abstract：We investigated the epidemiological characteristics and the genotype distribution of Blastocystis hominis in urban region of southwest China, and the study may provide scientific references for the prevention and treatment of Blastocystis hominis. A total of 1 121 diarrhea patients and 319 healthy controls were selected from four sentinel hospitals in Kunming of southwest China from June 2014 to July 2015. The stool specimens were collected to detect the Blastocystis hominis with PCR. A structured questionnaire was applied to each diarrhea case and healthy control after stool samples collection for their clinical manifestation (e.g. vomiting, fever and dehydration), demographic data (age, sex and residence) and types of the stool samples (watery, mucoid, or bloody and other forms); the phylogenetic trees were constructed using the neighbor-joining method with 1 000 bootstrap replicates; reference strains were downloaded from the GenBank. Results showed that the detection rate of Blastocystis hominis was 4.2% in diarrhea cases; the prevalence of Blastocystis hominis in female was higher than that of in male (5.5%, 2.9%, P=0.027, OR=1.98, 95%CI=1.07-3.67); no significant difference was found among diarrhea cases with different age groups infected with Blastocystis hominis (χ2=3.933, P=0.950); however, there was remarkable seasonal trend for Blastocystis hominis (χ2=11.8, P<0.05); the difference in detection rate of Blastocystis hominis among diarrheacases from rural-urban fringe zone, urban and rural area was not significant difference (χ2=2.427, P=0.297), the Blastocystis hominis subtype I was absolute dominant strain in diarrhea cases and healthy controls. In conclusion, Blastocystis hominis was still common intestinal parasites in urban population, Blastocystis hominis subtype I was the most prevalence in this region, the pathogenicity and subtype distribution of Blastocystis hominis need to be continuously studied.
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2016, Vol. 32 
