Analysis The Relationship Between Hereditary Character And Host Animals Carried Hantavirus In Epidemic Areas Of Hebei Province

Objective: To understand the population constitution of rats, positive rate of host animals carried hantavirus (HV) and the relationship between hereditary character and host animals carried hantavirus in Hebei epidemic areas in order to guide the prevention and control for this disease.Methods:1 Investigate the epidemic areas;Capture rats and take rat lungs in sterile environment;2 Rat lungs were sliced with freezing microtome. Then HV positive lungs were screened with IFA after they were fixed by cold acetone;3 DNA was extracted from positive lungs and negative lungs;4 Search for special primers about microsatellite sites which have been found according to documents and GENEBANK, amplify the DNA and use Agarose Gel Electrophoresis to identify the PCR products;5 According to the results of Agarose Gel Electro- phoresis , to compare the positive lungs and negative lungs, negative lungs and negative lungs in the same areas and negative lungs and negative lungs, positive lungs and positive lungs in the different areas. Calculating the coefficient of similarity to understand the relationship of the population in the different areas.Results:1 Data of rats in 2008 indicated that the dominant host animal was Rattus norvegicus(Rn) that occupied 70.39% of the captured rats in Hebei province. In residential district, Rn and Mus musculus(Mus) were the dominant host animals that occupied 73.38% and 24.10% of the captured rats respectively.In field,Rn, Cricetulus triton and Mus were the dominant host animals that occupied 54.72%, 20.75% and 13.21% of the captured rats respectively. Density of rat in residential district(2.16%) was higher than that in field(0.53%).2 331 frozen sections of rat lungs were detected with IFA after they were fixed by cold acetone. There was 1 positive lung. The positive rate of host animals carried hantavirus was low in Hebei epidemic areas, host animals carried hantavirus was Rattus norvegicus in the residential district, the positive rat did not been detected in field and the others.3 According to the microsatellite amplifiable result of Rattus norvegicus, the differences between Rn carried hantavirus and Rn un-carried hantavirus could be showed in the same areas. The sites of D4mit20, D16mit4 and D18mit1 were not stabilization, but the strip could be showed in the site of D16mit4 in TANGSHAN, the site of D18mit1 only could be amplified in positive samples of CANGZHOU. The differences could not be showed between positive samples and negative samples in the sites of D2mit12, D3mit15, D3mit22, D7mit26, D12wox10, D12wox11 and D14mit2.4 According to the microsatellite amplifiable result of Rattus norvegicus, the differences among Rn un-carried hantavirus could be showed in the same areas. The sites of D4mit20,D16mit4 and D18mit1 were not stabilization; the sites of D2mit12, D7mit26 and D12wox10 were stabilization and had low variation; the sites of D3mit15, D3mit22, D12wox11 and D14mit2 showed polymorphism and had high variation, this results showed the differences among Rn un-carried hantavirus in the same areas.5 According to the microsatellite amplifiable result of Rattus norvegicus, the differences among Rn un-carried hantavirus should be showed in the different areas. The sites of D3mit15, D12wox10, D12wox11 and D14mit2 had some differences, this results showed Rn un-carried hantavirus had differences in heredity, the other sites did not show the difference. According to coefficient of similarity, it could be found that the genetic relationship of population was far and the genetic distance was large between HANDAN and BAODING, SHIJIAZHUANG and TANGSHAN, CANGZHOU and HANDAN. The coefficient of similarity was 0.8 between CANGZHOU and TANGSHAN, the genetic relationship of population was near. 6 According to the microsatellite amplifiable result of Rattus norvegicus, the differences among Rn carried hantavirus should be showed in the different areas. The strip could be showed in the site of D16mit4 in TANGSHAN, the site of D18mit1 only could be amplified in CANGZHOU. The sites of D2mit12 , D3mit22 , D12wox10 and D14mit2 showed monomorphism in the different areas, the positive samples had no difference. The site of D7mit26, D12wox11 and D3mit15 could be stable amplified and showed polymorphism. The results of the site of D4mit20 were not similar to the anticipant results. According to coefficient of similarity, it could be found that the genetic relationship of population was near and the genetic distance was small in TANGSHAN, CANGZHOU and BAODING.Conclusion:1 Rn and Mus were the dominant host animals in residential district of Hebei; Rn, Cricetulus triton and Mus were the dominant animals in field. In one word, Rn, generally existing, was the dominant host animal in Hebei province.2 According to the ten microsatellites sites amplifiable result of Rattus norvegicus, the significant differences between Rn carried hantavirus and Rn un-carried hantavirus did not be found, it was no evidence to show that the hereditary factors could make Rn to infect HV.3 According to coefficient of similarity, it could be found that the genetic relationship of population was near between CANGZHOU and TANGSHAN, the genetic relationship of population was far and the genetic distance was large between HANDAN and BAODING, SHIJIAZHUANG and TANGSHAN, CANGZHOU and HANDAN. It could be found that the Rattus norvegicus of the different areas had differences in hereditary.4 The sites of D4mit20, D16mit4 and D18mit1 were not stable, the sites of D2mit12, D7mit26 and D12wox10 showed monomorphism and the sites of D3mit15, D3mit22, D12wox11 and D14mit2 showed polymorphism.