Community-based cross-sectional study of carcinogenic human liver fluke in elderly from Surin province, Thailand.

BACKGROUND Opisthorchis viverrini infection is a serious public-health problem in Southeast Asia. It is associated with a number of hepatobiliary diseases and the evidence strongly indicates that liver fluke infection is the etiology of cholangiocarcinoma. OBJECTIVES This study aimed to determine Opisthorchis viverrini infection in elderly people in Surin province, Northeastern Thailand. METHODS A community-based cross-sectional survey was conducted among 333 elderly in 17 districts of Surin province, during one year period from January to December 2011. O. viverrini infection was determined using Kato's Thick Smear technique and socio-demographic were collected using predesigned semi-structured questionnaires, respectively. RESULTS A total of 333 elderly including 116 males and 217 females were selected from different study sites. Overall intestinal parasitic infection was 16.2%, predominantly in O. viverrini (9.91%) and followed by Strongyloides stercolaris (4.80%) and hookworm (1.50%), respectively. The O. viverrini infection was found higher in males (13.8%) than females (7.83%), and frequently in elderly 60-70 year old with 14.2%. Chi-square testing indicated that education and occupation were significantly associated with O. viverrini infection (P value = 0.02). The distribution of O. viverrini infection was found in 11 districts which was covered 64.7% of the studies areas. The highest prevalence was found in Thatum with 39.1%, and followed by Sangkha (24.0%), Buachet (21.1%), Samrong Thap (19.1%), Si Narong (15.0%), and Ratanaburi (13.3%) districts. CONCLUSION This findings stress that O viverrini is still a problem in Thailand. We confirmed, for the first time, the high endemicity of human O. viverrini infections in elderly in Surin province of Thailand, underlying the fact that mass treatment and health education are urgently required.