Farmland Soil Contamination of Ascaris Lumbricoides Eggs and Its Causing Factors in Tibet Autonomous Region from 2015 to 2016

Objectives To analyze the status of ascaris lumbricoides eggs contamination in farmland soils in Tibet Autonomous Region, and to explore the factors influencing ascaris lumbricoides eggs-contaminated soils.

Methods The survey was conducted in 420 administrative villages from 7 cities in Tibet by simple random sampling method. Saturated sodium nitrate floatation method was used to detect ascaris lumbricoides eggs in soil samples collected from monitoring stations in different cities in Tibet. The authors analyzed the correlation of detection rates of ascaris lumbricoides eggs and live ascaris lumbricoides eggs with soil environment and management methods of rural areas environment and administrative hygiene.

Results The detection rate for ascaris lumbricoides eggs was 26.81% in 690 soil samples. The detection rate for live ascaris lumbricoides eggs was 16.67% in 690 soil samples. The detection rates of ascaris lumbricoides eggs and live ascaris lumbricoides eggs in all the cities were statistically significant(χ² values were 40.00 and 39.91, respectively, P < 0.05). The detection rates of ascaris lumbricoides eggs in 2015 and 2016 were 30.68% and 22.46%, respectively. The detection rates of live ascaris lumbricoides eggs in 2015 and 2016 were 14.79% and 18.77%, respectively. Multivariate analysis showed that the construction of rural communities and the input of health funds were important influencing factors for the detection of ascaris lumbricoides eggs. Construction of rural living environment, construction of rural communities, the establishment of hygienic villages, and complexity of plant roots were important factors affecting the detection of live ascaris lumbricoides eggs.

Conclusions The risk of ascaris infection in Tibet still existed, and there were regional differences. The analysis results suggested that it was necessary to strengthen the new rural construction, and to continue promoting the rural environmental health work.