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Objective:To study the phenotype and genotype distribution of Yersinia pestis ( Y. pestis) in different natural foci of plague in China, so as to provide scientific basis for plague prevention and control. Methods:A total of 2 184 strains of Y. pestis isolated from different time periods, regions, hosts and vectors in 11 plague natural foci of China since 1943 were selected for biochemical type identification, glycolysis test, virulence factor test [capsule antigen (F1), pesticin Ⅰ (Pst Ⅰ), virulence antigen factor (VWa), pigmentation factor (Pgm)], different region (DFR) typing and clustered regularly interspaced short palindromic repeats (CRISPR) typing. Results:There were 16 biochemical types of Y. pestis in the natural foci of plague in China, and each biochemical type showed obvious regional distribution in each foci. Most strains were positive for ass hide glue glycolysis (89.79%, 1 961/2 184), maltose (80.13%, 1 750/2 184), glycerol (94.23%, 2 058/2 184), and denitrification (82.78%, 1 808/2 184), and negative for rhamnose (88.78%, 1 939/2 184) and melibiose (85.62%, 1 870/2 184). Virulence factor test results showed that 99.95% (2 183/2 184) of Y. pestis were F1 positive; 99.73% (2 178/2 184) of Y. pestis can produce Pst Ⅰ; 73.31% (1 601/2 184) of Y. pestis were VWa positive and 26.69% (583/2 184) were VWa negative; Pgm positive strains accounted for 72.62% (1 586/2 184), Pgm negative strains accounted for 21.52% (470/2 184), and Pgm mixed type strains accounted for 5.86% (128/2 184). According to DFR typing results, there were 52 genotypes in 2 184 strains of Y. pestis, of which 19 were major genotypes and 33 were minor genotypes. CRISPR typing revealed 16 major genotypes, of which 7 were newly discovered. Conclusion:The phenotypes and genotypes of Y. pestis in various natural foci of plague in China are diverse and have geographical distribution characteristics.
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Objective:To learn about the characteristics of natural foci and the spatial distribution of mosquitoes and ticks in Yadong County, Tibet Autonomous Region (Tibet for short).Methods:The eco-geographical characteristics, demographic information, agricultural and animal husbandry data of the natural foci in Yadong County, Tibet were collected from the Yadong County 2020 statistical yearbook, vector data were collected from the Yadong County Center for Disease Control and Prevention, and the data of the meteorological station in Yadong County from 2010 to 2021 were collected from the World Weather Network. In July 2021, a total of 20 mosquito and tick sampling points were selected for field investigation according to the distribution characteristics of vegetation and animal husbandry of Yadong County. The light trap method was used to trap mosquitoes, and the manual inspection and flag dragging method were used to catch ticks. The spatial distribution characteristics of mosquitoes and ticks were analyzed.Results:The natural epidemic foci in Yadong County, Tibet, were high in the north and low in the south, with an elevation difference of about 5 000 m. It was rich in water resources, and the average runoff of Yadong River was 20.1 m 3/s. The climate in the north was cold and dry, and the south was mild and humid. From 2010 to 2021, the annual average station air pressure in Yadong County was 452.8 mmHg (1 mmHg = 0.133 kPa), the maximum monthly average temperature, precipitation and relative humidity of air were 8.7 ℃, 134.5 mm and 81.3%, respectively, all in July. A total of 6 897 diptera insects were attracted by the light trap method, all of which were non-blood-sucking mosquitoes. The total density was 163.77 pieces/(lamp·h), the dominant population was Muscaridae, accounting for 89.69% (6 186/6 897). In different sampling areas, Xiayadong Township collected the most mosquitoes, accounting for 67.17% (4 633/6 897); the others were Yadong County and Shangyadong Township, accounting for 27.36% (1 887/6 897) and 5.47% (377/6 897), respectively. A total 2 014 host animals were examined, and 23 parasitic ticks were caught, of which 20 were of the genus Ixodes and 3 were of the genus Haemophilus. No free ticks were caught in all ticks sampling points. Conclusions:The climate and ecological environment of the natural foci in Yadong County, Tibet have obvious vertical gradient. Mosquitoes and ticks are active, but the density is not high, the density of mosquitoes is generally high in the south and low in the north.
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Objective:To investigate the genotypes of clustered regularly interspaced short palindromic repeats (CRISPR) of Yersinia pestis ( Y. pestis) and it's regional distribution in the plague natural foci of Qinghai-Tibet Plateau. Methods:In this study, 1 004 strains of Y. pestis isolated from different hosts and vectors in different regions from 1954 to 2011 were selected as experimental objects, which preserved in Qinghai Institute for Endemic Disease Prevention and Control, and DNA of Y. pestis was extracted by traditional phenol-chloroform method. Three CRISPR loci (YPa, YPb and YPc) were amplified by PCR and sequenced, respectively, and the CRISPR sequences were compared with the CRISPRDictionary database recently reported in the literature to identify CRISPR spacer. For the spacer discovered for the first time at each CRISPR locus, Blast sequence alignment was performed in the National Center for Biotechnology Information (NCBI) database to speculate the source of gene sequence. Genotyping of Y. pestis from Qinghai-Tibet Plateau was performed based on the polymorphism of CRISPR spacer array. Results:A total of 53 spacers were found in 1 004 strains of Y. pestis, of which 6 spacers were newly discovered, namely a105, a106, a107, b51, b52 and c14. The 1 004 strains of Y. pestis were divided into 10 groups with 44 different CRISPR genotypes, and 15 new genotypes were found. The dominant genotypes of Y. pestis were G26-a1', G7, G22, G24-a1', G22-a1', G9 and G26-a1'a60 in Himalayan Marmot plague natural foci, and G37-a6' in Qinghai Microtinae plague natural foci. Conclusion:The CRISPR genotypes of Y. pestis in the plague natural foci of Qinghai-Tibet Plateau are high diverse and have significant regional distribution characteristics.
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Objective:To investigate and determine the epidemic scope of plague natural foci in Yulong County of Yunnan Province, and to assess its epidemic risk, so as to providing basis for monitoring, prevention and control of plague.Methods:In 2017, 2 - 3 natural villages were selected from 8 villages and towns in Yulong County according to geographical landscape, altitude, population and area. During October and November, small mammal hosts and their parasitic fleas were captured by the night trap (cage) method, Yersinia pestis was isolated from host animal organs, and plague F1 antigen and antibody were detected by colloidal gold test. Plague specific antigen was detected by reverse indirect hemagglutination test (RIHA) in self-dead small mammals. Animal serum from dogs, cats and mice were collected for detection of plague F1 antibody by indirect hemagglutination test (IHA). Results:A total of 1 019 host animals including self-dead small mammals were collected, belonging to 22 species, 12 genera, 6 families, 4 orders. Among them, 1 016 small mammals were captured by tools and 996 were outdoors, with the capture rate of 25.28% (996/3 940). The dominant species of small mammals outdoors were Apodemus chevrieri, Rattus (R.) rattus, Eothenomys miletus and Crocidura attenuate, which accounted for 30.32% (302/996), 22.09% (220/996), 17.37% (173/996) and 12.35% (123/996). The common species were Niviventer confucianus, R.nitidus and R.norvegicus, which accounted for 8.13% (81/996), 4.02% (40/996) and 1.81% (18/996). A total of 20 small mammals of 9 species were captured indoors in the residential area, and the capture rate was 1.11% (20/ 1 800). The dominant species were R.norvegicus, R.nitidus and Mus musculus, which accounted for 30.00% (6/20), 25.00% (5/20) and 10.00% (2/20). Eighteen small mammals of 8 species were infected with 67 parasitic fleas, belonging to 5 species, 5 genera, 3 families. The total flea infection rate was 1.77% (18/1 019) and the total flea index was 0.070. Among them, 49 parasitic fleas from 4 small mammals of 3 species were collected indoors. The flea infection rate was 19.05% (4/21) and the flea index was 2.333. Leptopsylla segnis had the highest flea infection rate of 9.52% (2/21) and flea index of 0.571. Ctenocephalides felis had the highest flea index of 1.571 and flea infection rate of 4.76% (1/21). They were the main flea species on the body surface of small mammals in residential areas. There were 14 small mammals infected with parasitic fleas outdoors, and 18 fleas in 5 species were collected with flea infection rate of 1.40% (14/998) and flea index of 0.018. Among them, Leptopsylla segnis had the highest flea infection rate was 0.50% (5/998) and the flea index was 0.005. The flea infection rate of Neopsylla specialis specialis was 0.40% (4/998), and the flea index was 0.004. Ctenophthalmus quadratus had the highest flea index of 0.007, and the flea infection rate ranked the third with 0.30% (3/998). The flea infection rate and flea index of Frontopsylla spadix spadix were the lowest, which were 0.20% (2/998) and 0.002, respectively. Ctenophthalmus quadratus, Leptopsylla segnis and Neopsylla specialis specialis were the dominant parasitic fleas on the surface of outdoor small mammals. A total of 419 indicator animal sera were collected, including 402 dog sera. One of them was positive by IHA, with a positive rate of 0.25% (1/402). Seventeen serum samples were collected from cats and mice, and IHA test results were negative. Yersinia pestis was isolated and cultured from the organs of small mammals and the detection of Yersinia pestis by colloidal gold test was negative. RIHA test of self-dead small mammals was negative. Conclusion:A plague indicator animal positive spot is newly found in the plague natural foci in Yulong County, and the plague epidemic monitoring, prevention and control in this region should be strengthened.
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Objective:To investigate the contents of soil metal elements in the plague high incidence area and resting area in the plague natural foci of Qingnan region in Qinghai Province, and to compare and analyze the differences of the contents of soil metal elements between the two areas.Methods:A total of 69 soil samples were collected from 11 sites in the plague high incidence area (Yushu Prefecture) and resting area (Guoluo Prefecture) in Qingnan region, including 39 samples from high incidence area and 30 samples from resting area. The contents of 12 soil metal elements, such as iron (Fe), magnesium (Mg), calcium (Ca), barium (Ba), cobalt (Co), copper (Cu), manganese (Mn), lead (Pb), rubidium (Rb), titanium (Ti), vanadium (V) and zinc (Zn), were measured by X-ray fluorescence spectrometry and SPSS 20.0 software was used for Spearman correlation and other statistical analysis.Results:The contents of Fe and Ca in the soil of the plague natural foci of Qingnan region were relatively high. The contents of 12 soil metal elements in the high incidence area were significantly higher than those in the resting area ( P < 0.01 or < 0.05). There were statistical significant differences in the contents of Mg, Ca, Ba, Mn, Pb and Zn in the soil among the sample plots of the plague high incidence area ( P < 0.01 or < 0.05). There were statistical significant differences in the contents of Fe, Mg, Ca, Rb and Ti in the soil among the sample plots of the plague resting area ( P < 0.05 or < 0.01). Except for Mg and Ca, Fe was positively correlated with other metal elements in the high incidence area and resting area ( P < 0.01 or < 0.05), and Fe was strongly positively correlated with Rb, Ti and V ( r = 0.780 - 0.838). Mg was only positively correlated with Ca in the high incidence area and resting area ( P < 0.01). Ca was negatively correlated with Mn, Pb, Rb, Ti, V and Zn in the high incidence area, and with Rb and Zn in the resting area ( P < 0.01 or < 0.05). The rest of the metal elements were mostly positively correlated in the high incidence area and resting area. Conclusions:The contents of Fe and Ca are rich in the plague natural foci of Qingnan region in Qinghai Province. There are correlations among most soil metal elements in the high incidence area and resting area. The correlation between the contents of soil metal elements in the plague natural foci and the epidemic of plague is worth further exploring.
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Objective:To analyze the pathogenic characteristics of Yersinia pestis in a plague natural foci in Qinghai-Tibet Plateau. Methods:In this study, 1 378 strains of Yersinia pestis isolated from different regions, hosts and vectors in Qinghai-Tibet Plateau from 1954 to 2016 were taken as the research objects. Phenotypic characteristics, plasmid spectrum and genotype of the strains were studied by using conventional techniques and molecular biological techniques. The etiology and geographical distribution of the plague were studied. Results:There were 6 biochemical types of Yersinia pestis in Qinghai-Tibet Plateau, namely Qinghai-Tibet Plateau, Qilian Mountain, Gangdis Mountain, Kunlun Mountain A, Kunlun Mountain B and Chuanqing Plateau. This study found that the Qinghai-Tibet Plateau type strain was not only distributed in north Tibet Plateau, but also distributed in south Tibet, and the distribution of Gangdis Mountain type strain extended to south Tibet. Four virulence factors (capsule antigen, yersinin, virulence antigen and pigmentation factor) were found in 79.97% (1 102/1 378) Yersinia pestis. The results also showed that there were 12 kinds of plasmids carried by Yersinia pestis strains in Qinghai-Tibet Plateau, which constituted 17 kinds of plasmid spectrum. There were 3 kinds of the largest plasmids with taxonomic properties, forming their respective relatively independent distribution areas. The study of different regions (DFR) type showed that 5, 8, 14, 19, 32 and 44 of 1 378 strains were the main genotypes, and the main genome types had obvious geographical distribution. Conclusions:All the tested strains have the characteristics of plague pathogen in Qinghai-Tibet Plateau. The polymorphism of the main hosts, vectors and the ecological landscape of plague geography in the plague foci in Qinghai-Tibet Plateau may lead to the diversity of biochemical characters, plasmid spectrum and geno types of Yersinia pestis.
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Objectives@#To establish a geographic information application system for analyzing the spatial and temporal distribution of major infectious diseases in various regions of the world and to assess the risk of importation of those diseases, to China.@*Methods@#We collected and integrated the following information on: 1) outbreaks and areas of epidemics of major infectious diseases in the world from 2000 to 2017, 2) cases of infectious diseases in arriving travelers through active surveillance at international entry-exit ports in mainland China from 2014 to 2016, 3) numbers of annual global international flights and travelers in the country. With the above information, a global space-time distribution database on major infectious diseases was then established, using the technology related to the system. Models regarding technologies on time-space analysis, probabilistic risk assessment and geographic information visualization, were applied to establish a geographic information system on risk assessment of infectious diseases that imported to China.@*Results@#Through integration of information on outbreaks and epidemic areas of 60 major infectious diseases in 220 countries and regions around the world, as well as 42 kinds of infectious diseases identified among the international arrivals in mainland China, a system was then developed. Information on the distribution of major infectious diseases and their potential risks in the worldwide various regions, characteristics of spectrum and disease burden of infectious diseases imported to each province of mainland China were displayed. Thus, risks on importing infectious diseases in each province via air way were able to be evaluated and simulated by the probabilistic risk assessment model, under the information on specific kind of infectious disease, outside China.@*Conclusion@#Geographic Information System on Risk Assessment Regarding Infectious Diseases Imported to China provides basic data for epidemiological reconnaissance and assessment on risks of importing infectious diseases outside China, thus would be helpful for the improvement of strategies on surveillance, prevention and control regarding the importing infectious diseases, in China.
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Objective To compare the coding sequences (CDS) of Yersinia pestis D106004 strain from Yulong County in Yunnan Province and Z176003 strain from Qing-Tibet Plateau in order to find the differences between their genomes and the genetic characteristics. Methods The CDS of Yersinia pestis D106004 strain and Z176003 strain were searched and compared by BLAST. Twenty-two differential CDS were selected to design 22 pairs of primers. PCR amplification was carried out in 119 representative plague strains from different isolation sources (natural foci of Himalayan marmot plague in the Qinghai-Tibet Plateau, natural foci of Apodemus chevrieri and Eothenomys miletus plague in Yunnan), time span of about 50 years, and distribution in six ecological types including Tibet, Qinghai, Sichuan, Gansu and Yunnan, and PCR products were sequenced and verified. The strains were all from the State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Infectious Disease Control and Prevention, Chinese Center for Disease Control and Prevention. Results In 119 representative plague strains of 6 ecological types, the cumulative sequence length of 22 differential CDS PCR amplification products was 2.13 × 106 bp. Among the 119 representative plague strains in the foci of Yulong D106004 strain and Qinghai-Tibet Plateau Z176003 strain, 22 differential CDS had high homology, there was no difference in 78.2％ (2047/2618) sequences of differential CDS, and 21.8％ (571/2618) sequences had three types of gene mutations ( deletion , missense and frameshift mutations). The characteristics of the differences were stable in the 6 ecological plague strains of the foci, and they were divided into 6 geographical distributions. Conclusion Yulong D106004 strain and Qinghai-Tibet Plateau Z176003 strain have high homology, close genetic relationship, and little difference in genome, but the genetic characteristics of different ecotype strains are stable.
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Objective To compare and analyze the soil eight metal elements contents of rat holes of three plague foci in Yunnan Province.Methods The soils were collected from the rat holes in Yulong,Jianchuan,and Lianghe plague foci.Calcium (Ca),iron (Fe),zinc (Zn),chromium (Cr),lead (Pb),manganese (Mn),cadmium (Cd),and copper (Cu) were quantified with flame atomic absorption spectrometry (FAAS).Data input,calculation and collation were conducted through Excel 2007,and statistical software SPSS 20.0 was used to carried out statistical analysis through rank sum test.Results The medians of Ca content in the rat hole soil of Yulong County,Jianchuan County,and Lianghe County,respectively,were 85.40,308.56,and 0.00 mg/kg;the medians of Fe were 2 569.07,1 950.16,and 975.72 mg/kg;the medians of Zn were 5.64,4.02,and 2.04 mg/kg;the medians of Cr were 1.09,3.06,and 0.71 mg/kg;the medians of Pb were 3.61,29.56,and 22.80 mg/kg;the medians of Mn were 223.01,212.97,and 80.43 mg/kg;the medians of Cd were 0.00,2.02,and 2.94 mg/kg;and the medians of Cu were 1.92,1.08,and 0.51 mg/kg.The contents of eight metal elements were statistically different in the soil samples between Yulong,Jianchuan,and Lianghe plague foci (H =80.538,127.687,202.583,185.359,124.747,150.057,91.346,228.546,P ＜ 0.05).Conclusions The content of Fe in soil of the three plague foci in Yunnan Province is abundant.The contents of metal elements of Yulong County and Jianchuan County are similar.
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We studied Yersinia infection and carriage in shepherd dog on the natural foci of Marmota himalayana plague and investigated the substitution or antagonism relationship among three pathogenic Yersinia in nature,providing a novel approach for prevention and control of plague.Blood sample and rectal swab specimens from shepherd dogs were collected.Rectal swab specimens were detected and isolated for Y.enterocolitican and Y.pseudotuberculosis.IHA was used to measure the positive rate of F1 antibody.Results showed that among 88,94,70 and 64 serum specimens respectively from Akesai,Subei,Sunan,and Tianzhu,IHA positive rates were 31.82％,32.98％,2.86％ and 1.56％ separately.A total of 236 anal swab specimens of shepherd dog were collected,among which one Y.kristensenii strain and 2 non-pathogenic Y.enterocolitica strain were recovered from Akesai and Subei respectively,where plague was violently prevalent in animals.All the results indicate that shepherd dogs in natural foci of M.himalayana plague where plague in animals are prevalent with non-pathogenic Y.enterocolitica,is an evidence of antagonism relationship in three pathogenic Yersinia.
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We investigated the current situation about free-ranging dogs infection with plague and provided relevant data for plague prevention and control in Karamay City.We examined the dog serum F1 antibody by indirect hemagglutination assay (IHA).Results showed that the F1 antibody was found in 1 of 13 dogs serum samples,and the positive rate was 7.69％.The free-ranging dogs plays an important role in controlling animal plague epidemic,and there are potential risk for local people's infection of plague.
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The plague occurs due to the long-term persistence of Yersinia pestis in natural environment.During the period of plague epidemic and quiescence,there are still some unknown scientific questions,such as where Yersinia pestis preserved,which mode preserved,and which mechanism caused plague epidemic.Thus,the researches on the preservation and viability of Yersinia pestis in every ecological element of plague natural foci will contribute to find the pattern for the occurrence and spread of plague.
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BackgroundThere are 137 soums of 17 provinces have plague foci in Mongolia. The 51.7% of them is case, 23.4%- low, 9.5% - high, 0.7% - hyper active. Main host of plague foci is marmot in Mongolia. According last20 year’s surveillance study, about 75.5% of Y.pestis was isolated from marmot, marmot carcassesand their flea. Human plague cases has been caused illegal hunting marmot in Mongolia. Even legaldocument which prohibited marmot hunting was appeared since 2005, people has been hunting marmotfor selling marmot meat, skin and other products. It is depends economy crises and other public issues inMongolia. Also influenced increase risk of human plague and being reverse result in plague preventionactivities.Materials and MethodsStudy was used data of rodent for zoonotic diseases suspicious which tested plague in National centerfor zoonotic disease (NCZD) in 2005-2015 and 13 local center for zoonotic diseases in 1988-2015. Datawas kept in NCZD and National archival authority. For mapping we used Arc View 3.2.ResultsTotally 397 event information of suspicious rodents and other animals was received in NCZD from 8 districtsof Ulaanbaatar city in 2002-2015. Most of information was received from Songinokhairkhan-64.2%district and smallest number was from Nalaikh district-0.3%. 92.2% of them were marmot, 0.1% of themwere marmot raw products for treatment purpose. Totally 1285 animal samples were tested by plaguedisease and the result was negative. Five hundred thirty tree marmots were carried to Ulaanbaatar from10 provinces. In that time plague foci were active and Y.pestis was isolated in provinces which marmotwas carried to Ulaanbaatar.In 1988-2015, totally 257 marmots and animals of 515 event information was received in15 provinces.Including 13.2% of them were birds, 84% of them marmot, 1.6% of them were livestock, 1.2% of themother animals. About 216 marmots were tested by plague. 51.2% of them were detected positive results.We develop conclusion based laboratory investigation result even it need high cost to take earlyprevention and response measures.Conclusion1. It is high risk to spread plague by carrying suspicious animal in urban area. Therefore, it is importantto take early response measures even it high cost. In further, increase cost and support rapid test ofhigh technology.2. To organize rational advertisement and increase knowledge of population about not doing illegalhunting, not selling marmot raw products in urban area, not using marmot raw products for treatmentuse and avoid contact with marmot carcasses.3. It is important to cooperate joint response measures with policeman, inspection agency andveterinary and human health sectors in Mongolia.
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The number of tick borne diseases is increasing in the world. More than 100000 tick borne encephalitis, tick borne encephalitis cases were registered every year. It occurred in 29 Europien, 4 Asian countries and became public health concern [1]. In our country, virus, tick detection started since 1980 with collaboration Russian scientists. From 1998, collaborative team of Public Health Institute (PHI), National centre for communicable diseases (NCCD), National center for infectious diseases with natural foci (NCIDNF) and Rssian scientists started study of tick prevalence and infection of tick borne encephalitis in Khuvsgul, Khentii, Bulgan, Orkhon, Tuv province. In study of B.Byambaa, M.Dash (1994), 18 species tick were found in Mongolia. Ticks found in 27 soums of 7 provinces. TBE virus infection of tick was 1.2-16.7% in I.persulcatus, 13.7-20% in D.nutalli. Far eastern subtype founded from patient, Siberian subtype founded from tick in Bulgan province of Mongolia. TBEV infection was 1.1-39% among population; highest infection was in Bugan, Khuder soum of Selenge province, Dadаl soum of Khentii provinces. 57.2-59.4% of population was tick bitten and 21-73.7% of them were developed clinical symptoms during surveillance. Symptoms include redness, fever, headache, skin rash, join paint. Most TBE cases were developed fever, headache, vomiting, stiff neck, paralysis. 96% of them typical, 4.4% of them atypical, 60% of them fever, 13.3% meningial, 10% meningoencephalitis among 90 cases in 1998-2004. In review, clinical symptoms of TBE cases that occurred Mongolia similar to cases caused Sibirein subtype.
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Objective To explore the existence of natural loci on Marmota himalayana plague in Sichuan province and to provide basis for prevention and control of the disease. Methods Both epidemiological investigation and laboratory tests were used to provide the host animal and fleas of the vectors with Yersinia pestis carriers. Results 30 species of animals were found to belong to 10 orders. Ochotona curzoniae and M.himalayana were the most common ones while 7 species of the fleas belonged to 7 genera and 3 families. M.himalayana was the main reservoirs while Callopsylla dolabris and Oropsylla silantiewi served as vectors. The 13 Y.pestis were identified from 43 Marmota samples. 8 samples were identified under IHA, with the highest titer of herding-dogs serum as 1 : 10 240. 19 samples were F1 antigen positive using RIHA and the highest titer of M.himalayana serum was 1:409 600. The major foci was 4545 km2, distributed at Dege county in Sichuan province. Conclusion We have confirmed the existence of natural foci on M. Himalayana plague in Sichuan province.
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O objetivo do presente trabalho foi avaliar a evolução da leishmaniose visceral (LV) no Estado de Sergipe, e o possível deslocamento dos focos do Sertão para o litoral nas últimas décadas, caracterizando alguns aspectos ambientais relacionados com a ocorrência dessa endemia. A metodologia consistiu da análise das notificações feitas à Fundação Nacional de Saúde entre 1972 e 1998, num total de 1.874 casos, que foram agrupados por município, por década e distribuídos nas três mesorregiões sergipanas: Sertão, Agreste e Leste (litoral). A incidência anual média da LV nas décadas de 70, 80 e 90 foi, respectivamente, de 1,96, 3,37 e 7,6. Constata-se uma grande expansão da doença em todas as regiões sem, contudo, haver deslocamento dos principais focos. Nas áreas onde se tem registrado o maior número de casos de leishmaniose visceral em Sergipe, o clima é úmido, com índices pluviométricos acima de 1.400 mm e baixas altitudes.
The objective of this study was to evaluate the evolution of the visceral leishmaniasis (VL) in Sergipe State, and a possible foci displacement from the Dry Land to the coast in the last decades, characterizing some environmental aspects related with the occurrence of the endemic disease. An analysis of all notifications send to the to National Health Foundation from 1972 to 1998 was performed. The 1.874 case identified were stratified by municipality, per decade and distributed in the three sub-areas of Sergipe: Dry Land, Transition Region and East (coast). The annual average incidence of LV in the decades of 70, 80 and 90 were respectively of, 1.96, 3.37 and 7.6 per inhabitants. An expansion of this disease is verified in all areas, however there is no displacement of the main foci. In areas, where the largest number of cases of visceral leishmaniasis in Sergipe State have been registered, the climate is humid, with pluviometric indexes above 1,400 mm and altitude is low.