[The infection status of Leptospira in rodents on the Heixiazi island of Heilongjiang province, China,in 2011].

OBJECTIVE: To study the infection status of Leptospira in rodents on Heixiazi island Heilongjiang province in 2011. METHODS: A total of 356 rodents were captured by night trap on the Heixiazi island from April to October 2011. The kidney tissue samples were collected by asepsis operation and the genomic DNA were extracted from them. Leptospira strains were confirmed by polymerase chain reaction(PCR) amplification of the 482 bp 23 S rDNA gene. Fifteen PCR products selected by the month were purified and sequenced by the methods of Sanger dideoxy, the sequences then compared with other Leptospira strains in Genebank, and phylogenetic analyses were drafted by software Mega 4.0. RESULTS: Among 356 rodents, the dominant species were Clethrionomys rutilus (39.3%, 140/356) and Apodemus agrarius (36.0%, 128/356). The infection rate of Leptospira was 11.0%, with 39 rodent samples detected positive. All the rodent species were infected except for Rattus norvegicus. The infection rate was 9.4% (12/128) in Apodemus agrarius, 12.9%(18/140) in Clethrionomys rutilus, 10.8%(7/65) in Microtus fortis Buchner. No significant difference was found between the infection rate and the species of rodents by chi square test(χ(2) = 1.92, P > 0.05). Among months, the infection rate was 5.6% (4/72) in May, 8.8% (5/57) in June, 12.8% (5/39) in July, 9.8% (5/51) in August, 33.3% (11/33) in September, 22.5% (9/40) in October,but no infection in April. There was significant difference in infection in different months (χ(2) = 32.92, P < 0.05). All the Leptospira in rodents on the Heixiazi island were in the same phylogenetic branch with a high similarity of 97.1%-99.6%, close with the Australia strain U90865 by the similarity above 96.3%. CONCLUSION: Leptospira is probably prevalent in rodents on the Heixiazi island, and the phylogene of the strains were similar. The infection rate in rodents was significantly different in months but not in hosts.

Complete Genome Sequence of Wohlfahrtiimonas chitiniclastica Strain SH04, Isolated from Chrysomya megacephala Collected from Pudong International Airport in China.

Wohlfahrtiimonas chitiniclastica bacilli that live in the larvae of a parasitic fly were recently isolated and are speculated to be the cause of fulminant sepsis. Here we report and analyze the complete genome sequence of Wohlfahrtiimonas chitiniclastica strain SH04. No complete genome sequence of a Wohlfahrtiimonas chitiniclastica isolate has been documented previously.

Complete genome sequence of an amur virus isolated from Apodemus peninsulae in Northeastern China.

Amur virus was recently identified as the causative agent of hemorrhagic fever with renal syndrome. Here we report the complete genome sequence of an Amur virus isolated from Apodemus peninsulae in Northeastern China. The sequence information provided here is critical for the molecular epidemiology and evolution of Amur virus in China.

Complete genome sequence of Seoul virus isolated from Rattus norvegicus in the Democratic People's Republic of Korea.

Seoul virus (SEOV) is responsible for 25% of cases of hemorrhagic fever with renal syndrome in Asia. Here we report the complete genome of strain DPRK08. The sequence information provided here is useful for understanding the molecular character of SEOV in the Democratic People's Republic of Korea (DPRK) and the circulation of SEOV in East Asia.

Species-specific polymerase chain reaction amplification of camel (Camelus) DNA extracts.

A sensitive polymerase chain reaction (PCR) method based on amplification of a specific DNA fragment was established for the identification of camel (Camelus) materials. The species-specific primer pair L183/H372 was designed based on the nucleotide sequence of the mitochondrial cytochrome b gene, and its specificity was confirmed by amplification of 3 camel (domestic double-humped camel, wild double-humped camel, wild one-humped camel) samples and 11 non-Camelus animal (sheep, goat, pig, chicken, cattle, fish, dog, horse, donkey, deer, and rabbit) materials. An expected 208 base pair fragment was amplified from camel materials; no cross-reactive or additional fragments were generated from other animal materials. Taq I restriction endonuclease digestion of the unpurified PCR product can be used routinely to confirm the camel origin of the amplified sequence.