ABSTRACT
Objective To perform an epidemiological investigation on a case with visceral leishmaniasis in Zhengzhou City, Henan Province, and to identify the source of infection, so as to illustrate the transmission chain and assess the risk of local leishmaniasis transmission. Methods The medical data were collected from a case with visceral leishmaniasis in Zhengzhou City, and the patient’s bone marrow smears were detected by microscopy. Serum anti-Leishmania antibody test and PCR assay were performed among high-risk residents and all dogs in the village where the patient lived. Sandflies were captured using light traps and artificial traps, and the captured female Phlebotomus chinensis was subjected to PCR assay. The internal transcribed spacer 1 (ITS1) gene was amplified with a nested PCR assay using the genomic DNA extracted from visceral leishmaniasis patients, positive dogs and sandflies, and the sequences were aligned with those download from NCBI. In addition, a phylogenetic tree was created based on the ITS1 gene. Results The visceral leishmaniasis patient had recurrent irregular fever, reduced complete blood counts, low hemoglobin, and a large number of Leishmania amastigotes in bone marrow smears, and was therefore diagnosed as visceral leishmaniasis. Both rk39 rapid diagnostic test and PCR assay tested negative among 324 residents living neighboring the patient’s residence, while 21.39% (43/201) dogs were positive for rk39 rapid diagnostic test and 13.93% (28/201) positive for PCR assay. There were 17 female Ph. chinensis tested positive for Leishmania (0.82%) by PCR assay, and the ITS gene sequences from visceral leishmaniasis patients, positive dogs and sandflies shared a 100% homology with L. infantum. The Leishmania species was therefore characterized as L. infantum. Conclusions L. infantum infection occurs in visceral leishmaniasis patients, dogs and sandflies in Zhengzhou City, indicating a complete transmission chain and a high transmission risk of visceral leishmaniasis by L. infantum. Intensified control measures are required to prevent local transmission of leishmaniasis in Zhengzhou City.
ABSTRACT
Objective To identify the cause and mode of transmission of a gastroenteritis outbreak in a village, Henan province. Methods Gastroenteritis patients were identified through family visits, interviewing the village doctors and reviewing diagnosis and prescription records at the village health clinic. Cases were defined as onset of one of the four symptoms from the village resident during July 20 to August 12,2010. The symptoms would include diarrhea ( ≥ 3 times/day), abdominal pain, nausea or vomiting. A retrospective cohort study was conducted to assess the association between drinking raw well water or eating noodles rinsed by raw well water and gastroenteritis. Stools or vomits of the ease-patients and the well water samples were tested for bacterial pathogens. Results Data for 60 case-patients were collected. All cases occurred in the northern part of the village. Persons who used water from a public well in the northern part of the village had an attack rate of 55%, which was 3.5 times of those who did not use the well water (16%) (RR=3.5,95%CI: 1.2-10). Results from the retrospective cohort study showed that drinking un-boiled water from the well was a risk factor (RR=1.7,95%CI: 1.3-2.3). Laboratory testing showed that total coliform and E. coli both greatly exceeded the limit considered safe for drinking, indicating there was fecal contamination in the well water. No bacterial pathogens were detected in the patients' stools or vomits. Conclusion The outbreak was mainly caused by drinking contaminated water from the public well in the northern part of the village.
ABSTRACT
Objective To compare genomic expression differences between androgenic complete hydatidiform mole (AnCHM) and normal first trimester villi with similar gestation weeks,and search for potential adjuvant diagnostic molecular markers.Methods Short tandem repeat (STR) detection was used to identify AnCHM,human oligonucleotide array U133 Plus 2.0 was used to measure genomic expression differences between AnCHM and normal villi,and quantitative fluorescent RT-PCR was used to verify array of several genes.Results Nine of 11 histologically diagnosed complete hydatidiform moles were found to be AnCHM by means of STR,and the other 2 were biparental complete hydatidifonn mole (BiCHM). Compared with villi,oligonueleotide array showed 279 genes (0.72%,279/38 500) were over expressed and 1710 genes (4.44%,1710/38 500) under expressed in AnCHM.Bioinformatics analysis found that differentially expressed genes were involved in multiple biological processes and pathways.Changes of imprinting genes,growth hormone genes and chorionie somatomammotropin hormone genes were especially remarkable.Conclusions Pathogenesis of AnCHM is a complex process involving multiple genes and pathways.Altered expression of imprint genes may play important roles in the process.