Nosocomial transmission of human granulocytic anaplasmosis in China.

Context: Human granulocytic anaplasmosis (HGA) is an emerging tick-borne disease in China. A cluster of cases among health care workers and family members following exposure to a patient with fulminant disease consistent with HGA prompted investigation.

Objective: To investigate the origin and transmission of apparent nosocomial cases of febrile illness in the Anhui Province.

[Distribution and molecular characteristics of Vibrio cholerae serogroups O1 and O139 isolates in estuary of Pearl River].

Objective: Through systematic monitoring of the number and strain types of O1 and O139 Vibrio cholerae in the Pearl River estuary waters to analyze it's relevance with the temperature of environment, and the relevance between strains in water and isolates during outbreaks and epidemics as well as to estimate the methods used for environmental water detection and the potential role in cholera surveillance program.

Methods: Twenty-four stations along the Pearl River were selected and the water samples were collected monthly from March 2006 to February 2007. V.

Rickettsial Seroepidemiology among farm workers, Tianjin, People's Republic of China.

High seroprevalence rates for Anaplasma phagocytophilum (8.8%), Coxiella burnetii (6.4%), Bartonella henselae (9.

[Molecular typing of Neisseria meningitidis serogroup C strains with pulsed field gel electrophoresis in China].

Objective: To study the characteristics of epidemiology and molecular typing on Neisseria meningitidis serogroup C strains associated with outbreaks of Anhui province and sporadic cases in China, using pulsed field gel electrophoresis (PFGE).

Methods: 212 Neisseria meningitidis serogroup C strains were isolated from invasive meningococcal cases, close contacts and healthy carriers, including 48 strains from Anhui province with 38 strains associated with serogroup C outbreaks. PFGE were performed by genomic DNA digestion with Nhe I restriction enzyme.

[Surveillance on Rickettsia in epidemic areas of scrub typhus in Xinyang areas of Henan].

Objective: To understand the epidemic status of Rickettsia in Xinyang areas of Henan province.

Methods: Samples including liver, spleen, kidney from mouse and chigger mites from Xinyang areas and serum samples were detected by nested-polymerase chain reaction (PCR) and indirect immunofluorescence assay (IFA).

Results: In 62 viscus samples from mice organs, the positive rates were 16.

Follow-up analysis on the epidemic strains of Orientia tsutsugamushi in the first outbreak of scrub typhus in Henan Province, China.

To obtain knowledge of the genetic characteristics and types of the epidemic strains of Orientia tsutsugamushi in the first outbreak of scrub typhus in Henan Province, genus and type-specific primers were employed to amplify a fragment of the gene of 56 kDa protein. Serotyping demonstrated that, of the 19 patients [15 patients in recovery phase (10-40 days) and 4 of patients in acute phase (1-7 days)], 4 were infected with Gilliam type, 8 with Kato type, 6 with Karp type, and 1 with an unknown type. Successful genotyping was obtained for only 3 patients, indicating that 2 were infected with Karp type and 1 with Taiwan Kato type.

Molecular epidemic survey on co-prevalence of scrub typhus and marine typhus in Yuxi city, Yunnan province of China.

Background: Human rickettsioses are worldwide zoonoses and it is not easy to differentiate them from other infectious diseases because of their atypical manifestation. In recent years the number of patients with fever of unknown causes from Hongta District CDC, Yuxi city of Yunnan Province has been increasing significantly in the summer. Diagnosis of scrub typhus was made by local clinicians.

[An epidemiologle investigation of hantaviruses carried by rodent hosts in Hunan province].

Objective: To explore the hantavirus infection and their genotype in rodents in Hunan.

Methods: Hantavirus antigens in the rat lungs from Hunan province were detected by immunofluorescence assay. Partial S and M segment in antigen-positive samples were amplified by RT-PCR, and then sequenced.

[Molecular typing of the pathogenic Yersinia enterocolitica strains with pulsed field gel electrophores isolated in China].

Objective: To investigate the epidemiological and molecular typing features of the pathogenic Yersinia enterocolitica strains isolated in China,using pulsed field gel electrophoresis(PFGE) and standardized PFGE method as well as typing database of Yersinia enterocolitica.

Methods: PFGE analysis was performed as Laboratory Directions for molecular subtyping of Salmonella by PFGE (PulseNet,USA) with some modifications and the results of PFGE were analyzed by BioNumerics soft (Version 4.0, Applied Maths BVBA, Belium).

Genetic differentiation of Chinese isolates of Rickettsia sibirica by partial ompA gene sequencing and multispacer typing.

Current data on rickettsiae and rickettsial diseases in China remain limited. Using partial ompA gene sequencing and multispacer typing, we identified 15 rickettsial isolates from China. All isolates were found to belong to Rickettsia sibirica subsp.

[Sequence analysis on sorbitol fermentation related genes in Vibrio cholerae].

Objective: To Investigate the differences of sorbitol fermentation related genes and optimize molecular analysis method for distinguishing an epidemic with nonepidemic strains of Vibrio cholerae.

Methods: Sequence analysis on four genes of sugar fermentation stimulation protein, periplasmic maltose-binding protein, periplasmic phosphate-binding protein and periplasmic amino acid-binding protein.

Results: In this study, the following data was noticed: for O1 serogroup El Tor biotype V.