Infection of Babesia in domestic animals in Western Yunnan Province, China / 中国人兽共患病学报

The objective of this study was to investigate Babesia infection among domestic animals in Western Yunnan Province and provide scientific evidence for developing control measures.A total of 1 073 domestic animals blood samples (274cattle,395 sheep,354 dogs,33 horses and 17 donkeys) were collected in 12 counties in Western Yunnan Province.Genomic DNA was extracted and a near full-length 18S rRNA gene sequence of Babesia was amplified by using nested PCR.Babesia species was identified by Blast program and phylogenetic tree.It was indicated that 50 samples were infected with Babesia,belonging to 5 species and with the infection rate of 4.66％.Among 274 cattle blood samples,11 were infected with Babesia (4.01％).Four of them were Babesia bovis and seven of them were Babesia bigemina.Among 395 sheep blood samples,38 were infected with Babesia (9.62 ％),37 of them were Babesia odocoilei-like parasites and 1 of them was Babesia capreoli-like parasites.Horses and donkeys were negative.In conclusion,domestic animals in Western Yunnan Province are infected with many kinds of Babesia,which threaten stock raising development and human health.It is necessary to strengthen prevention of babesiosis and investigate infection rate of babesiosis in human.

Investigation on Anaplasma phagocytophilum infection in rodents from forest areas in northeastern China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate the prevalence of Anaplasma phagocytophilum in rodents from forest areas in northeastern China.</p><p><b>METHODS</b>PCR amplification, followed by sequence analysis was carried out. The sequences of 16S rRNA and gltA gene fragment amplified from rodent specimens were compared with corresponding part of the sequences deposited in GenBank.</p><p><b>RESULTS</b>A total number of 276 rodents were tested, including 102 in Jilin province, 61 in Helongjiang province and 113 in Inner Mongolia autonomous region. The positive rates were 8.82%, 1.64% and 0.00%, respectively. The infection rate in rodents infected by ticks was 11.30 times higher than that in rodents without ticks (P = 0.002). The S. A. phagocytophilum 16S rRNA sequences from rodents in Jilin and Heilongjiang were identical and differed in 3-5 bases compared with the corresponding parts of A. phagocytophilum from America, Sweden and Japan. Compared with the sequences registered in GenBank, the nucleotide sequence of gltA varied from 87%-97% and its deduced amino acid sequence changed from 84%-99%.</p><p><b>CONCLUSION</b>A. phagocytophilum infection was presented in rodents from Jilin and Heilongjiang province.</p>

Study on the coinfection status of Borrelia burgdorferi sensu lato and spotted fever group Rickettsia in ticks from Hunchun, Jilin province / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the coinfection status of Borrelia burgdorferi sensu lato (B.b.s.l) and spotted fever group Rickettsia (SFGR) in Hunchun of Jilin province, China.</p><p><b>METHODS</b>Polymerase chain reaction (PCR) was used to detect the 5S-23S rRNA intergenic spacer of B. b. s. l and ompA of SFGR in ticks was collected in Hunchun,Jilin province. The amplification products of positive ticks were sequenced, and phylogenetic analysis was conducted by PHYLIP software package.</p><p><b>RESULTS</b>The infection rate of B. b. s. l was 36.0% in Ixodes persulcatus ticks and the SFGR was discovered in I. persulcatus ticks,with an infection rate of 2.0%. The coinfection rate of both agents was 2.0%. In 327 Dermacentor siltarum ticks, the positive rates of B. b. s. l and SFGR were 30.9% and 29.1% respectively. 55 ticks (16.8%) were coinfected with the two pathogens. The sequence analysis of B. b. s. l showed that the B. b. s. l in Jilin area, which were highly homologous, all belonged to B. garinii genotypes. The sequence analysis of SFGR positive products showed that the DNA secquence of the newly detected agent (JL-95) was close to the two previously described rickettsiae which were detected in I. ricinus from Slovakia (called IRS3 and IRS4). Phylogenetic relationships inferred from the comparison of these sequences with those of other genus Rickettsiae indicated that JL-95, IRS3 and IRS4 constituted a new rickettsial genotype and formed a separate cluster among the spotted fever group Rickettsiae.</p><p><b>CONCLUSION</b>Coinfection of B. b. s. l and SFGR existed in Hunchun, Jilin province. The sequencing of specific fragment confirmed a new SFGR which was different from other rickettsiae known in China.</p>

Investigation on Borrelia burgdorferi sensu lato in ticks and rodents collected in Da Xing-An Mountains Forest areas of China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To detect and study the types of Borrelia burgdorferi sensu lato in ticks and rodents from Da Xing-An Mountains Forest areas of China.</p><p><b>METHODS</b>Nested PCR was performed to amplify 5S-23S rRNA intergenic spacer of B. burgdorferi. Positive products were analysed by restriction fragment length polymorphism (RFLP) and single strand conformation polymorphism (SSCP), specimens showing unique RFLP profile were sequenced and analysed.</p><p><b>RESULTS</b>1336 Ixodes persulcatus, 144 Dermacento silvarum, 144 Haemaphysalis concinna and 145 rodents of 9 species were collected from 16 sections of Da Xing-An Mountains Forest areas of China. Specific fragments were amplified from 293 I. persulcatus and 6 D. silvarum and 5 rodents of 4 species. B. burgdorferi was not detected in H. concinna. Among the positively tested I. persulcatus, 209 contained B. garinii genospecies and 45 contained B.afzelii genospecies based on RFLP. Moreover, B.garinii genospecies consisted of B. garinii 20047 and B. garinii NT29. 17 adult I. persulcatus were simultaneously infected with B. garinii 20047 and B. garinii NT29. Nine adult I. persulcatus were simultaneously infected with B. garinii 20047 and B. afzelii. Four adult I. persulcatus were simultaneously infected with B. garinii 20047 and B. garinii NT29 and B. afzelii. Two D. silvarum were infected with B. garinii 20047, 1 D. silvarum with B. garinii 20047, 2 D. silvarum with B. afzelii. 3 rodents were infected with B. garinii 20047 while 2 rodents were infected with B. garinii NT29. Mixed infection was not found in D. silvarum and rodents. In addition, nine I. persulcatus and one D. silvarum specimens showed unique RFLP pattern. Data from sequential analysis showed that they all belonged to B. garinii. PCR-SSCP profiles of 5S-23S rRNA intergenic spacer of B. burgdorferi in the positive specimens exceeded 36 types; B. garinii 20047 showed 16 types while B. garinii NT29 showing 11 types, B. afzelii showing 9 types. SSCP profiles of the specimens coinfected with multiple B. burgdorferi was relatively complex.</p><p><b>CONCLUSION</b>The infection of B. burgdorferi was found in the ticks and rodents in Da Xing-An Mountains Forests areas. The infection rate of I. persulcatus was high. B. garinii was predominant genospecies, and the population of B. burgdorferi was heterogeneous in the area. Mixed infections of different B. burgdorferi genospecies in ticks were found. I. persulcatus and Clethrionomys rufocanus were possibly served as major vector and major host for B. burgdorferi, respectively, suggesting that further study is needed to confirm the coinfection in humans and animals in this region.</p>