ABSTRACT
Objective To understand the epidemiologic characteristics of endemic typhus in Baoshan city. Methods Epidemiological data were collected and characteristics were analyzed. IgG antibody(Ab) of Rickettsia mooseri and Orientia tsutsuganushi in serum of patients were tested using both Weil-Felix and IFA method. The Rickettsia mooseri gltA gene, Rickettsia prowazekii gltA gene,Orientia tsutsugamushi 56 kDa protein gene, SFGR ompA gene, Ehrlichia sp. 16S rRNA gene and Anaplasma sp. 16S rRNA gene in spleen of mice were examined by PCR. Results Fifty- eight endemic typhus cases were found in Longyang district of Baoshan city, during July to August, 2009.Among them, 48 cases were confirmed by clinical diagnosis and 10 cases by laboratory tests. The Ab of Orientia tsutsugamushi Karp serotype was detected in 3 cases from laboratory diagnosis. The spleen samples from 85 Rattns flavipectus were tested using PCR. Of them, 3 samples for Rickettsia mooseri gltA gene showed positive (positive rate was 3.5% ), and the homology of 3 Rickettsia mooseri and Rickettsia mooseri Wilmington strain (GenBank U59714.1) was 100% through comparing gene sequence. The results of PCR for detecting Rickettsia prowazekii, Orientia tsutsugamushi, SFGR,Anaplasma sp. and Ehrlichia. sp were all negative. Conclusion The outbreak of endemic typhus was confirmed in Longyang district of Baoshan city through epidemiological data, clinical diagnosis and laboratory tests. Rickettsia mooseri DNA was detected in the dominant Raw flavipectus, suggesting that endemic typhus did exist in the local areas.
ABSTRACT
Objective To understand the epidemiological features of two rabies cases in Baoshan city year 2006 and 2007 and to analyze its source of infection.Methods Questionnaires were used to do the epidemiologieal survey on each of the rabies cases.Brain timue samples of rabies patients were collet to detect the rabies virus by direct immunofluoreseence assay(DFA)and RT-PCR assay.Homology and phylogenetic tree were analyzed.based on the whole nucleotide and deduced amino acid sequence of P,M and N gene of rabies virus followed by molecular epidemiological analysis.Results In July 2006,one human rabies case was identified in Longyang district,and another one in Tengchong county in Baoshan city in 2007.The degrees of exposure of these two patients was all at degreeⅢ.Two brain tissue samples among the dead patients(No.CYN0601H and CYN0701H)were confirmed positive by both DFA and RTPCR assay.The homology analysis of P,M and N gene sequences among CYN0601H,CYN0701H and other rabias strains isolated from other provinces and other counties.showed that the samples in Baoshan city shared the highest homology with the strains in Thailand.Phylogenetic analysis indicated that the two samples were very dose and all belonged to genetype 1 Lyssavirus,with the closest relationship between samples in Baoshan city and strains in Thailand.Conclusion It Was confirmed on the virus molecular level that the two patients in Baoshan city were both suffered from rabies.The prevalent strains in Baoshan city WaS probably imported from foreign country,suggesting that prevention and control measures on rabies virus in the boarder areas of Yunnan should be strengthened.