Influence of geographic, knowledge and behavioral factors on Opisthorchis viverrini infection in the Northeast of Thailand

Objective: To determine the influence of geographic, knowledge and behavioral factors on Opisthorchis (O.) viverrini infection in the Northeast of Thailand. Methods: This cross-sectional study was conducted by using four datasets of years 2016 and 2017. Generalized linear mixed model was employed to analyze association between geographic, knowledge and behavioral factors and O. viverrini infection. Results: Totally there were 1 885 participants. The prevalence of O. viverrini infection was 10.03%. Geographic factors that showed statistically significant association with O. viverrini infection in the Northeast region were featured by at least a dam and reservoir (Adj. OR = 4.21, 95%CI: 2.49-7.13, P 50 dogs and cats per village (Adj. OR = 3.40, 95%CI: 2.17-5.31, P 50% of its areas (Adj. OR = 1.91, 95%CI: 1.04-4.01, P = 0.036), as well as low to moderate levels of knowledge (Adj. OR = 1.60, 95%CI: 1.32 to 1.94, P < 0.001), consumed raw fish (Adj. OR = 1.90, 95%CI: 1.02 to 3.52, P = 0.040) and consumed processed raw fish (Adj. OR = 3.03, 95%CI: 2.20 to 4.18, P < 0.001). Other significant covariates were gender and age of the respondents. Conclusions: O. viverrini infection still remains a public health problem of the Northeast of Thailand. Geographic and demographic factors, knowledge, and consumption behaviors of raw fish products are significantly associated with O. viverrini infection.

Distribution and Abundance of Opisthorchis viverrini Metacercariae in Cyprinid Fish in Northeastern Thailand

To increase public health awareness for prevention of opisthorchiasis caused by eating raw freshwater fish, the distribution and abundance of Opisthorchis viverrini metacercariae (OV MC) was investigated in freshwater fish obtained from 20 provinces in northeastern Thailand between April 2011 and February 2012. A cross-sectional survey was conducted on 12,890 fish consisting of 13 species randomly caught from 26 rivers, 10 dams, and 38 ponds/lakes. Fish, were collected in each of the rainy and winter seasons from each province. Fish were identified, counted, weighed, and digested using pepsin-HCl. Samples were examined for OV MC by a sedimentation method, and metacercariae were identified under a stereomicroscope. OV MC were found in 6 species of fish; i.e., Cyclocheilichthys armatus, Puntius orphoides, Hampala dispar, Henicorhynchus siamensis, Osteochilus hasselti, and Puntioplites proctozysron from localities in 13 provinces. Among the sites where OV MC-infected fish were found, 70.0% were dams, 23.7% were ponds/lakes, and 7.7% were rivers. The mean intensity of OV MC ranged from 0.01 to 6.5 cysts per fish (or 1.3-287.5 cysts per kg of fish). A high mean intensity of OV MC per fish (>3 cysts) was found in 5 provinces: Amnat Charoen (6.5 cysts), Nakhon Phanom (4.3), Mukdahan (4.1), Khon Kaen, (3.5) and Si Sa Ket (3.4). In conclusion, OV MC are prevalent in natural cyprinid fish, with the infection rate varying according to fish species and habitats.

Current Health Status of School Children in a Rural Area of Northeast Thailand

Background : To assess whether nutritional  deficiencies and parasitic infection, which can be used to indicated poor health status, are still important and common problems  in Northeast  Thailand.Objective : To assess the current health status of school children in a rural area of Northeast  Thailand.Design: Descriptive studySetting : Primary School in the village of nakamnoi, Nampong district, Khon Kaen province.Subjects : School children from pratom 3 to 6 aged  8 – 12 yearsIntervention : Antihelmintic drugsResults : The prevalence of anaemia at the end of the rainy season was 30.5 percent, however, during the hot dry season was 30.5 percent, however, during the hot dry season prevalence was only 5.3 percent. 70 out of 158 children (45.2 percent) were found to be infected  with one or more parasites. Hgb and Hct values were found to increase significantly from the pre – antihelmintic treatment visit to the post-treatment visit in both infected and uninfected groups. The improvement was more significant in the uninfected group than the infected group.Conclusion : The health status of the school children is generally good. The main health problems found were  anaemia and parasitic infections.

Albendazole in the treatment of uncomplicated strongyloidiasis by using the agar late method

The  agar  plate  method  is  a  new  and  highly  sensitive  technique  for  diagnosis  strongyloidiasis.  We  detected  strongyloidiasis  from 331  villagers  in  Khon  Kaen  province  by  using  this  technique.  There  were  82 cases  (24.77%)  positive  for  Strongyloides  stercoralis.  They  were  administered  albendazole  400  mg  orally  once  a  day  for  3 consecutive  days.  Only   51  cases  submitted  stools  for re -  examination  two  weeks  after  treatment.  There  were  38  cases  cured  (74.51%)  This  study  showed  that  strongyloidiasis  is  still  a  high  cause  of  infection  in Khon  Kaen  and  the  dosage  of  400  mg  orally  once  a  day  for  3  consecutive  days  of  albendazole  showed  effective  treatment.

Current Roles of Liver Fluke on Occurrence of Cholangiocarcinoma

in PDF file

Predictive Statistical Model for the Risk of Cholangiocarcinoma in Northeast Thailand

Background and Objective: Cholangiocarcinoma (CHCA) is the most common cancer in Thai people especially in the Northeast of Thailand. Primary prevention is very important for CHCA control. This study attempted to find the exposures associate with CHCA in order to develop a predictive statistical model for CHCA in people in Northeast Thailand.Methods: This study was carried out in 2007 as a nested case-control study within the Khon Kaen cohort study at Cancer Unit, Khon Kaen University. The cohort recruitment was performed during 1990 to 2001. There were 108 CHCA cases occurred in the cohort and individual matched control was randomly selected for each case (1:1), matched by age, sex and date of recruitment to the cohort.Results: For the predictive model, was: logit (CHCA) = 0.69 X Opisthorchis Viverrini, OV (egg in stool finding) with the precision of 56.48% (95%CI:= 51.25-61.71), sensitivity 54.02% (95%CI: = 46.32 - 61.59), specificity 66.67% (95%CI: = 50.45 - 80.43), positive predictive value 87.04% (95%CI:=79.21-92.73) and negative predictive value 25.93% (95%CI:=17.97-5.25).Conclusion: The results of this study suggested that OV infestation has high association with CHCA. To reduce the incidence of CHCA, liver fluke control is priority work for health policy.Keywords: Cholangiocarcinoma, Risk factors for cholangiocarcinoma, Predictive model for cholangiocarcinoma

Specific and common antigens of Clonorchis sinensis and Opisthorchis viverrini (Opisthorchidae, Trematoda)

The antigenic characterizations and serological reactions of human liver flukes, Clonorchis sinensis and Opisthorchis viverrini, were analyzed by immunoblot. The antigenic profiles of the crude extract of Clonorchis contained major proteins of 8, 26-28, 34-37, 43, and 70 kDa, and those of Opisthorchis 34-37, 43, 70, and 100 kDa. Of these, the 8, 26-28 and 34-37 kDa bands of Clonorchis and the 100 kDa of Opisthorchis were major components of each excretory-secretory antigen. The 8 and 26-28 kDa bands were specific to Clonorchis but the 100 kDa of Opisthorchis cross-reacted with the sera of clonorchiasis, and the 34-37, 70 and 100 kDa bands cross-reacted with sera of other helminthiases. The frequency and intensity of the immunoblot reactions were positively correlated with the intensity of the liver fluke infection.