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Background: Kashi Prefecture of Xinjiang is one of the most seriously affected areas with anthroponotic visceral leishmaniasis in China. A better understanding of space distribution features in this area was needed to guide strategies to eliminate visceral leishmaniasis from highly endemic areas. We performed a spatial analysis using the data collected in Bosh Klum Township in Xinjiang China., Methods: Based on the report of endemic diseases between 1990 and 2005, three villages with a high number of visceral leishmaniasis cases in Bosh Klum Township were selected. We conducted a household survey to collect the baseline data of kala-azar patients using standard case definitions. The geographical information was recorded with GIS equipment. A binomial distribution fitting test, runs test, and Scan statistical analysis were used to assess the space distribution of the study area., Results: The result of the binomial distribution fitting test showed that the distribution of visceral leishmaniasis cases in local families was inconsistent (χ(2) = 53.23, P < 0.01). The results of runs test showed that the distribution of leishmaniasis infected families along the channel was not random in the group of more than five infected families. The proportion of this kind of group in all infected families was 63.84 % (113 of 177). In the Scan statistical analysis, spatial aggregation was analyzed by poisson model, which found 3 spatial distribution areas 1) Zone A was located in a center point of 76.153447°E, 39.528477°N within its 1.11 mile radius, where the cumulative life-incidence of leishmaniasis was 1.95 times as high as that in surrounding areas (P < 0.05); 2) Zone B was located in a center point of 76.111968°E, 39.531895°N within its 0.54 mile radius, where the cumulative life-incidence of leishmaniasis was 1.82 times as high as that in surrounding areas (P < 0.01); and 3) Zone C was located in a center point of 76.195427°E, 39.563835°N within its 0.68 mile radius, where the cumulative life-incidence of leishmaniasis was 1.31 times as high as that in surrounding areas (P < 0.05)., Conclusions: The spatial distribution of visceral leishmaniasis-infected families was clustered. Thus, the proper use of this finding would be an improvement in highly endemic areas, which could help identify the types of endemic areas and population at high risk and carry out appropriate measures to prevent and control VL in this area as well.

Few outbreaks of the desert sub-type of zoonotic visceral leishmaniasis (VL) have been described worldwide. In 2008, the incidence rate of VL in Jiashi County, Xinjiang Uygur Autonomous Region in the western part of the People's Republic of China, increased more than twenty-folds compared to the average annual incidence rate. The majority of the cases (96.6%) occurred among <2 year-old infants. For the first time in the desert area of Xinjiang, the parasites were isolated from bone marrow aspirates, using the NNN medium culture approach. The genetic analysis of the ITS-1 nucleotide sequence indicated that three isolates from eastern Jiashi County were genetically closely related and belonged to the Leishmaniainfantum group. However, they differed from an isolate from Kashi city which was classified as a member of the Leishmaniadonovani group.

Objective: To investigate the epidemiological status of visceral leishmaniasis in Hamangou coal mine area of Korla City of Xinjiang Uygur Autonomous Region., Methods: Based on a hint of possible existence of patients, a retrospective survey was carried out house by house to find cases with suspected signs/symptoms of the disease. Meanwhile, a survey on current status was conducted, including physical examination (liver and spleen palpation) to those less than 15 years-old, leishmanin skin test and rk39 immunochromatographic strip test for part of the residents. Bone marrow smears were examined for the cases with clinical signs/symptoms and positive rk39 strip test. Sandflies were collected using routine methods in and around the area, identified, and dissected to find infection of promastigotes., Results: Leishmanin skin test was performed in 185 people with a positive rate of 21.1% (39/185), 39 out of 140 local residents who have lived there for more than 6 years showed positive (27.9%), while all residents who have lived less than 6 years and children under 5 years old were negative. Of the 81 children under 15 years old with a negative skin test, one showed positive for rk39 strip test, and leishmania body was found in the bone marrow smear of this case, so confirmed as visceral leishmaniasis. 12 sandflies were identified as Phlebotomus alexandri, and natural infection with promastigotes was found in one sandly., Conclusion: The investigation confirms that visceral leishmaniasis is endemic in the Hamangou coal mine area.

Objective: To probe time-space clustering on the distribution of visceral leishmaniasis (VL) in Kashgar Region., Methods: Based on the geographic information system, a Poisson model of time-space statistical software was applied to analyze data over the past 11 years in the Kashgar Region. Zones with clustering phenomenon were conformed by geographic location and remote sensing images., Results: There existed three high risk clustering zones and corresponding time frames of VL in Kashgar Region. The center location of zone A was located in E 76.08 degrees, N 39.52 degrees, with radius as 6.58 km. The high risk time frame was from January 1st of 1999 to December 31st of 2003. Within the zone and time frame, the relative risk (RR) of VL incidence was 45.98 times higher than those outside the scope (P < 0.0001). Zone B' s center location was at E 79.20 degrees, N 39.91 degrees, with the radius as 4.93 km. Its high risk time frame was from January 1st of 2002 to December 31st of 2006. Within the zone and time frame, the RR of VL incidence was 9.58 times higher than those outside of the scope (P < 0.0001). Zone C' s center location was in E 76.23 degrees, N 39.40 degrees, and the radius was 7.63 km, with the high risk time frame from January 1st of 2000 to December 31st of 2004. Within the zone and time frame, the RR of VL incidence was 5.18 times higher than the one from outside of the scope (P < 0.0001)., Conclusion: The incidence of VL in Kashgar Region was non-randomly distributed while there existed obvious time-space clustering, with all of three high risk clustering zones located in oasis area where appeared the focus area for control and surveillance of VL.

Health education activities including distribution of brochures, posters, and lectures were conducted in selected villages of a kala-azar endemic-township, Kashi city of Xinjiang in 2004-2006. Questionnaire was carried out before and after health education in residents and students. The percentage of correctly answering all 5 questions on leishmaniasis in residents and primary/secondary school students increased from 0.7% and 0 to 54.2% and 70.7% respectively, indicating that health education can raise public awareness for the disease prevention and control.

Objective: To investigate the transmitting phlebotomine sandfly in Minfeng County, a newly-identified endemic area of visceral leishmaniasis in the south of Talim Pendi of Xinjiang., Methods: Sandflies were collected using routine methods in and around the Yatonggusi village of Andier Township. The sandflies were identified to get their composition. Sandfly density was calculated following an observation at a given spot and time-period, and their appearance was recorded at night-time and day-time. Sandflies were dissected to analyze the gonotrophic cycle and to find infection of promastigotes., Results: Phlebotomus wui was identified as the transmitting vector of visceral leishmaniasis in Andier Township, which occupied 99.2% of the sandflies collected. The first and second ten-day period of June was the first peak of its seasonal distribution. Analysis of the gonotrophic cycle revealed that Ph. wui was an exophilic species and appeared nocturnally for feeding with preference to human blood. Natural infection with promastigotes was found in 2 sandflies., Conclusion: Phlebotomus wui is the transmitting vector for visceral leishmaniasis in the newly found endemic area of south Xinjiang.

Objective: To investigate the epidemiological status of visceral leishmaniasis in Minfeng county, a newly identified endemic area in south Xinjiang, China., Methods: Based on a hint of possible existence of patients, a retrospective survey was carried out house by house in Andier Township of the county to find cases with suspected signs/symptoms of the disease in the past 20 years including those died. Meanwhile, a survey on current status was conducted, including physical examination(liver and spleen palpation) to those under 15 years-old, leishmanin skin test and rk39 immunochromatographic strip test for part of the residents., Results: The investigation covered 313 local residents and revealed no case with present illness but 60 cases with a history of suspected signs/symptoms including 13 deaths, traced back as visceral leishmaniasis. Leishmanin skin test was performed in 171 people with a positive rate of 99.4% and 28 out of 29 suspected cases showed positive (96.6%). rk39 immunochromatographic strip test was conducted in 197 people with a positive rate of 10.2% (20/197) and 19.4% (6/31) in those with a history of suspected signs/symptoms., Conclusion: The epidemiological investigation indicates that the Andier Township of Minfeng County is an endemic area of visceral leishmaniasis.