[Survey on human rabies cases and its viral molecular biological features in Baoshan city, Yunnan province].
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 epidemiological survey on each of the rabies cases. Brain tissue samples of rabies patients were collect to detect the rabies virus by direct immunofluorescence 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 degree III. Two brain tissue samples among the dead patients (No. CYN0601H and CYN0701H) were confirmed positive by both DFA and RT-PCR assay. The homology analysis of P, M and N gene sequences among CYN0601H, CYN0701H and other rabies 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 close and all belonged to genetype 1 Lyssavirus, with the closest relationship between samples in Baoshan city and strains in Thailand.


CONCLUSIONS
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.
Zhang
Hai-Lin
HL
Yunnan Provincal Institute of Endemic Disease Control and Prevention, Dali 671000, China.
Tang
Qing
Q
Tao
Xiao-Yan
XY
Wang
Xiao-Guang
XG
Zhang
Yun-Zhi
YZ
Yang
Wei-Hong
WH
Mi
Zhu-Qing
ZQ
Wang
Jing-Lin
JL
Zhang
Yu-Zhen
YZ
Feng
Yun
Y
Zheng
Wei-Bin
WB
Lu
Guo-Yong
GY
Li
Sheng-Guo
SG
D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D016679:Genome, Viral; D005838:Genotype; D006801:Humans; D008297:Male; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D011818:Rabies / Q000453:epidemiology* / Q000235:genetics / Q000821:virology*; D011820:Rabies virus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D017422:Sequence Analysis, DNA