Endmic Trends Of Schistosomiasis In The Dongting Lake And Its Impact On The Sub-populations At High Risk

Objective:To analyze endemic trendency of schistosomiasis from 2000-2009 in the Dongling Lake region by using an epidemiological database of Hunan Province andcheck prevalence and infection intensity of schistosoma japonicum in the three sub-populations.(school children, fishermen and farmers) at high risk, and evaluate their impact as transmission source of schistososmiasis. Outcomes obtained from this study will provide a scientifically base for improving current control strategies and activities in the Dongting Lake.Methods:Endemic trends (2000-2009) analysis of schistotsomiasis in the Dongting Lake region were by using a schistosomiasis database in the Hunan province. Villages sampled for data analysis were based on the stratified sampling from the database. A cross-section survey in field was used to examine prevalence and infection intensity of Schistosoma japonicum in the three sub-populations(children, fishermen and farmers) at high risk. Kato-Katz was used for parasitological assessment. Data collected was processed and analyzed by the version of SPSS 13.0Results:1. Prevalence and infection intensity of Schistosoma japonicum in human and buffalos in the Dongting Lake region showed a declined trend from 2000-2009. There was a statistical significant difference. Infection intensity of Schistosoma japonicum in the patients with schistosomiasis was increased. Snail areas keep relatively stable. Density of alive snails and infected snails showed a positive correlation.2. A 8.18% human infection rate of Schistosoma japonicum was detected in the three villages. A high prevalence (11.96%) of Schistosoma japonicum infection in human in the Dong Gou village were higher than those reported in Fongyang (7.07%) and Touchian (6.13%) villages. Prevalence of Schistosoma japonicum infection in the three villages were different and there was a statistical significance. There was no statistically different to infection intensity in population in the three villages.3. Male showed a high infection(11.05%) than infection(4.91%) of women. There was a statistical difference of infection rate in sex.4. Ageage groups in the villages presented various infection rates, a high infection of schistosomiasis was reported in the age 40-49 years old. A lowest infection rate (1.72%) located in the group (5-9 years old).5. Prevalence and infection intensity of Schistosoma japonicum infection in the three sub-populations at high risk presented a significant difference. Children was reported a lower infection (2.84%), fishermen made a high position in the infection (40.4%).Conclusions:1. Endemic trends of prevalence and infection intensity of Schisto soma japonicum in Hunan province was declined due to effective control programme from 2000-2009. Infection intensity of Schistosoma japonicum in the patients infected was somewhat increased.2. Based on our study, fishermen in the Lake region is a very Important transmission source to schistosomiasis. This is due to their occupational exposure. Organizations of schistosomiasis control should pay attention to apply more effective strategy to control Schistosoma japonicum infection in this sub-population.3. Further enhance and improve examinations and chemotherapy for schistosomiasis control in the people (farmers)s who live closely to embankments and beaches so that transmission source of schistosomiasis can be effectively reduced or controlled.4. School students or children are the sub-population at high risk of exposure to Schistosoma japonicum infection. Health education in school is a kind of effective approach to reduce schistosomiasis in this sub-population at high risk. This strategy should be further enhanced and materials used for health education should be updated.