Investigation Of Toxoplasma Gondii Infection Rate And Reinfection Analysis Of Positive Samples In Pork In Guilin Area

Objective(s):The aim of this study was to clarify the distribution of Toxo plasma gondii infection in special populations and pork sales in Guilin,Guangxi,and the possibility of acquiring T.gondii infection through consumption of fres h pork,the most common meat product in China.Method(s):Blood samples of hospitalized patients in critical care Depart ment of Affiliated Hospital of Guilin Medical College were randomly collected f or aseptic isolation serum,specific PCR and human ELISA detection.Subseque ntly,the positive samples were statistically analyzed,and the relationship betwe en T.gondii infection and gender,age and disease type in critically ill patients in Guilin,Guangxi.A total of 535 fresh pork samples were randomly collected fro m 26 sampling sites in 16 markets and 10 fresh supermarkets in five urban areas of Lingui District,Diecai District,Xiangshan District,Qixing District and Xiufe ng district.Through DNA extraction,specific PCR amplification,preparation of tissue homogenates,isolation of supernatant and ELISA detection,the infection status of T.gondii in commercially available pork in Guilin,Guangxi was clarifi ed.KM mice were intragastric infected with fresh pork samples positive for T.g ondii,and blank control was set.After 28 days of infection,the blood of mice w as collected aseptically by the method of ophthalmotomy.After the mice were ki lled by the method of cervical dislocation,the spleen and brain tissues were coll ected aseptically.After weighing,morphological and pathological examination,DNA extraction,PCR amplification,tissue homogenate preparation and ELISA detection,the possibility of toxoplasma infection caused by eating fresh pork in critically ill patients in Guilin area was investigated.Result(s):Among 260 blood samples from critically ill patients,97 were positive for T.gondii Ig G antibody,with a detection rate of 37.31%.Among the97 positive samples of T.gondii Ig G antibody,there were 73 in male patients an d 24 in female patients,the detection rates were 41.01% and 29.27%,respectivel y,and the female patients were slightly lower than the male patients.The detecti on rates of T.gondii Ig G antibody were 41.18%,40.91%,36.56% and 36.72% in young,young,middle-aged and elderly patients with critical illness in different age groups.There was no significant difference among all age groups.The detec tion rate of T.gondii Ig G antibody in the serum of critically ill patients and the g ender and type of the patients were statistically analyzed,but the results were no t obvious.The results of agarose gel electrophoresis showed that the T.gondii re peat sequence with fragment size of 529 bp could not be amplified in other samp les except positive control.6 out of fresh pork samples were positive for T.gond ii antibody,with a positive rate of 1.12%.The PCR results showed that except f or the positive control,the other samples could not amplify the T.gondii repeat s equence with the fragment size of 529 bp.KM mice reinfection experiment sho wed that fresh pork samples with positive antibodies to T.gondii did not cause t he reinfection of mice.Conclusion(s):The detection rate of T.gondii in critically ill patients in G uilin,Guangxi was high and random,but there was no correlation with the disea se type.The positive rate of T.gondii Ig G antibody in pork sold in Guilin city w as 1.12%,indicating that there was a certain level of T.gondii infection,but the possibility of human consumption of T.gondii infected pork was small.