[Prevalence of Angiostrongylus cantonensis infection in snails for sale in Fuzhou and Xiamen].

OBJECTIVE: To investigate the prevalence of Angiostrongylus cantonensis infection in snails for sale from Fuzhou and Xiamen of Fujian Province. METHODS: During 2009-2012, two markets and five restaurants from each city were selected as surveillance sites. A. cantonensis infection rate in Pomacea canaliculata, Bellamya aeruginosa and Cipangopaludina cathayensis was examined two times per month. More than 50 P. canaliculata or C. cathayensis, and about 500 g B. aeruginosa were collected in each site. A. cantonensis larvae infection was determined by lung-microscopy in P. canaliculata, and by tissue homogenate method in C. cathayensis and B. aeruginosa, respectively. RESULTS: In markets, a total of 5,744 P. canaliculata were collected, and the infection rate of A. cantonensis larvae was 13.8% (753/5 744) with the lowest prevalence in 2009 (8.4%, 28/334) and the highest one in 2011 (16.7%, 361/2,160). The overall infection rate of A. cantonensis showed an increasing trend over the past years (P < 0.05). In restaurants, 879 P. canaliculata snails were examined in Xiamen City, and the infection rate was 12.8% (877/6 879). No significant difference was found among years (P > 0.05). A. cantonensis larvae were found from P. canaliculata for sale in different seasons with no statistical difference (P > 0.05). 19,843 B. aeruginosa snails were collected in markets from the two cities, and the infection rate was 0.2% (31/19 843). The infection rate was highest in 2011 (0.3%, 16/5,953) and lowest in 2010 (0.04%, 2/4,706). All the 361 C. cathayensis snails were negative. CONCLUSION: A. cantonensis larvae are found in P. canaliculata and B. aeruginosa from markets and restaurants of Fuzhou and Xiamen in different seasons during the years.

[Surveillance on the prevalence of soil-transmitted nematode infection in Fujian in 2006-2010].

OBJECTIVE: To analyze the prevalent trend of soil-transmitted nematode infection in Fujian Province during the past 5 year surveillance and evaluate the control effect. METHODS: From 2006 to 2010, fecal samples of the inhabitants of 3 years old and above were collected every November and examined for intestinal helminth eggs by the modified Kato s thick smear technique at the 2 surveillance sites: Punan village of Zhangzhou and Gushan village of Shaowu. Cellophane tapes were used to detect pinworm eggs for children aged 3-12. Soil samples were also collected from vegetable field, lavatory, courtyard and kitchen of 20 randomly selected families (in 2 villages) each with stool egg-positive findings and examined for ascaris eggs by a modified saturated sodium nitrate floatation method. RESULTS: The prevalence of soil-transmitted nematode infection at the surveillance sites decreased from 45.3% (946/2087) in 2006 to 15.1% (226/1494) in 2010, with a reduction of 66.6%. Among the infected subjects, hookworm infection occupied 75%-85%, while ascaris or trichuris infections each accounted for less than 10%. In terms of infection intensity, 65.2%-85.5% of the hookworm infection was light, and majority of the infected subjects were farmers. The pinworm prevalence in children were still high although it had dropped down from 46.1% (140/304) in 2006 to 29.8% (36/121) in 2010, declined by 35.4%. In the 5 years, totally 400 soil samples from 100 families were examined and 21 samples were found ascaris egg positive with viable eggs in only one sample. CONCLUSION: The 5 year surveillance reveals a decreasing trend of the soil-transmitted nematode prevalence but shows a relatively high hookworm infection rate in the population and pinworm infection in children.

[Prevalent trend of the infection of soil-transmitted nematodes in Fujian Province].

OBJECTIVE: To understand the endemic situation of soil-transmitted nematodes in Fujian Province. METHODS: According to the national guidelines, the survey spots were determined by clustered random sampling in nine prefectures (cities) of Fujian Province from 2007 to 2009. Residents of 3 years old and above were investigated. The eggs of roundworm, hookworm and whipworm in feces were checked by Kato-Katz method. Eggs per gram (EPG) in feces were calculated. The gender, age and education status of the investigated subjects were recorded. The results were evaluated in comparison to those in 1992 and 2003. RESULTS: Altogether 93 833 residents in 610 villages of 184 towns from 49 counties were investigated. The overall infection rate of soil-transmitted nematodes was 10.14% (9 511/93 833), decreased by 86.88% and 71.84% compared to that in 1992 and 2003, respectively. The prevalence of roundworm, hookworm and whipworm was 1.32%(1 234/93 833), 7.31% (6 863/93 833) and 1.73% (1 622/93 833), respectively. The average EPG of roundworm, hookworm and whipworm was 9 556, 526 and 156, respectively. The prevalence in males and females was 9.48% (4 385/46 246) and 10.77% (5 126/47 587), respectively, with a statistical difference (chi2 = 42.84, P < 0.01). There was also a statistical difference among the age groups (chi2 = 1 626, P < 0.01). The higher education level of the people, the lower prevalence (chi2 = 1 107, P < 0.01). CONCLUSION: The prevalence of soil-transmitted nematodes is on a downward trend in Fujian Province, but remained high in the underdeveloped areas. The hookworm infection rate is higher than the average of the nation.

[Survey on the current status of important human parasitic infections in Fujian province].

OBJECTIVE: To understand the prevalence of important human parasitic diseases in Fujian province. METHODS: According to the national guidelines, clustered random sampling was made for the survey. Modified Kato-Katz thick smear was applied to examine helminth eggs for soil-transmitted nematodes and Clonorchis sinensis. Cellophane and swab technique was applied for detecting Enterobius vermicularis eggs in children under 12. Questionnairing, skin test, serological test and eosinophil examination were carried out for Paragonimus infection. Questionnairing and serological test were used for Taenia infection and cysticercosis. Retrospective investigation was conducted with the data on outpatient and hospitalized cases with parasitic diseases. RESULTS: 45,736 people at 73 spots of 24 counties were investigated and 14 species of parasites were found. The overall infection rate of intestinal helminth infections was 36.15%. The prevalence of Ascaris lumbricoides, hookworms and Trichuris trichiura was 9.55%, 19.73% and 11.48% respectively. The infection rate of Enterobius vermicularis and Clonorchis sinensis was 22.06% and 0.60% respectively. The positive rate of skin test and serological test among skin test positives for Paragonimus infection was 7.07% and 9.23% respectively. The serology positive rate for cysticercosis was 2.28%, only 3 cases of taenia infection were found from 16371 persons investigated. Human infections with Angiostrongylus cantonensis, Diphyllobothrium latus, Taenia saginata, and Gnathostoma spinigerum were found for the first time in the Province. Metorchis orientalis and Echinostoma aegyptiaca infections in human were first recorded. CONCLUSION: The overall prevalence of soil-transmitted nematodes has decreased significantly in the province, although still highly prevalent in social-economically less developed areas. Meanwhile, attention should be paid to the food-borne parasitic infections in human population.