Molecular Epidemiology Of Rabies And Metabolomics Of Mice Infected By Rabies Virus

Chapter one Molecular epidemiology of rabiesRabies is a zoonotic infectious disease caused by rabies virus(RABV)infection with a high fatality rate.Rabies still kills tens of thousands of deaths worldwide each year and more than 95% of death cases occur in resource-poor Asian and African countries.China is a country with high rates of rabies,and the death of rabies is the third notifiable disease which can cause death.In spite of human cases have been declining steadily since 2007,rabies continues to spread into new areas.Recent years,north and west provinces report several cases of domestic animal rabies caused by wildlife and human rabies caused by bites of infected dogs.Meanwhile,the virus which belongs to new clade has appeared.Furthermore,all surrounding countries have prevalence of rabies.To study the clades and characteristics of RABV strains,the trend of rabies epidemic and relationship between China and surrounding countries,this research carry out the molecular epidemiology and spatiotemporal evolution analysis of rabies.This research verifies universality,sensitivity and specificity of reverse transcript PCR method to detect lyssavirus.The result shows that this method can detect 18 species of lyssavirus successfully.Then we use the gold standard of rabies diagnosis-direct immunofluorescence test(FAT)and nested reverse transcript PCR method to detect 306 brains samples of animal,amplify and sequence N gene fragments of 28 positive samples.We get 25 N gene sequences of recent samples,then combine information and sequences of N gene fragments of China and neighboring countries to perform molecular epidemiology studies.The result show that RABV in China can be divided to 4 clades,respectively is: Asian,Arctic-related,Cosmopolitan and Indian subcontinent.After analyze of the spread direction and distribution range of each clades,we conclude that the dog is still the mean vector of rabies.However,those rabies caused by wildlife such fox are ignored.In China,rabies has all over the country provinces,autonomous regions,and has distinct regional features.There are some persistent cross-border transmission events between China and surrounding countries.This research first defined cross-border transmission course of each clades.Chapter two Metabolomics of mice infected by rabies virusRABV is a typical neurotropic virus which can lead host illness and eventually die after the invasion of the central nervous system(CNS).However,there are only some mild neuropathological changes such as mild inflammation and neurodegenerative changes,cannot lead nervous system injury.At present,the machine of RABV elicits host to nervous system dysfunction is not clear.This research establishes RABV infection mice model,takes mice infected with fixed rabies virus CVS-11 and street-virus strain GDMM as object,selects two sampling points of middle and late stage of disease course.Then bases on liquid chromatography-mass spectrometry,combines PCA,PLS-DA and OPLS-DA multivariate statistical analysis to analyze differences between each groups and screen differential metabolites.This research obtains metabolomics profiling of RABV-infected mice brains screened by LC-MS,and the result shows that there are metabolic abnormalities in brains of RABV infected mice.At least 185 metabolites have changed,include neurotransmitters,nucleic acids and energy metabolism.Some of these metabolites have difference trends between fixed and street strain group,and it suggests that changes in central nervous system caused by RABV infection are different.This research provides a new clue to elucidate the pathogenesis of RABV.