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PubMed2005

Changes in the geographical distribution of tuberculosis patients in Veracruz, Mexico, after reinforcement of a tuberculosis control programme.

OBJECTIVE: Geographical information systems are valuable tools for studying tuberculosis (TB) epidemiology, but have been underused for the evaluation of TB control programs. We aimed to compare the geographical distribution of TB before and after the five elements of directly observed therapy, short course (DOTS) were strengthened in a Health Jurisdiction in Mexico in response to recommendations made by the WHO Global Tuberculosis Program. METHODS: All consenting persons detected by passive case finding between March 1995 and February 2000 who were confirmed to have acid-fast bacilli (AFB) in sputum underwent clinical and laboratory evaluation. A TB 'episode' was defined as the period of time between bacteriological diagnosis and treatment discharge by the local control programme. Distances of TB episodes from the nearest urban centre were determined according to recent transmission and multidrug resistance (MDR). RESULTS: During the first half of the study period, MDR episodes were located a median distance of 1.24 km from urban centres, which did not differ significantly from non-MDR episodes (1.14 km, P=0.56). In contrast, the median distance of MDR episodes increased 55% to 1.92 km during the second half, which placed them significantly further away out than non-MDR episodes (1.08 km, P=0.01). No changes in location were detected for recent transmission. CONCLUSION: While reinforcing the TB control programme reduced the incidence of MDR, the remaining episodes were located in poorer and more remote areas.

Antitubercular Agents↗
PubMedDate not supplied

[Geographic distribution of phlebotomine sandflies of the Lutzomyia intermedia (Lutz & Leiva, 1912) complex (Diptera, Psychodidae)].

The geographical distribution of Phlebotomine sandflies of the Lutzomyia intermedia complex is presented, based in collections for this study and in personal informations from other workers and bibliography. The subject is discussed, in relation to climate and to altitude and latitude. Lutzomyia intermedia s.s. was found in smaller altitudes and latitudes than Lutzomyia neivai; the last species seems to be better adapted to colder and drier climates than the first.

Animals↗
PubMed2005

[Species and geographic distribution of large-flowered taxa of Epimedium in China].

OBJECTIVE: To introduce species and geographic distribution of large-flowered taxa of Epimedium L. in China. METHODS: Resources investigation and taxonomy study. RESULTS: There are 27 species large-flowered taxa of Epimedium in China. CONCLUSION: 13 species in Sichuan, 9 species in Hubei, 8 species in Guizhou, 4 species in Hunan, 3 species in Guangxi, 2 species in Chongqing, 2 species in Yunnan, 1 species in Jiangxi, 1 species in Shanxi, 1 species in Jilin, 1 species in Liaoning and 1 species in Heilongjiang.

China↗
PubMed1996

[Description and validation of a predictive model of the geographic distribution of chronic home-bound patients].

OBJECTIVE: To find a predictive model for the geographical distribution of the homebound chronically ill in function of variables corresponding to censal areas. DESIGN: A study of an ecological type. SETTING: Raval Nord Health District, Barcelona. PATIENTS AND OTHER PARTICIPANTS: The study units are the 30 censal areas of Raval Nord. In each area researchers counted the number of homebound chronically ill recorded during the first three months of a home care programme (May 1994). MEASUREMENTS AND MAIN RESULTS: A multiple regression analysis was performed, with selection of the variables by the stepwise method of the SPSS-PC+ statistical package, taking as dependent variable "y" the number of homebound chronically ill per 1,000 inhabitants. The prognostic variables were taken from the 1991 municipal roll, and evaluated along with the distance in metres from each censal area to the primary care centre (PCC). The distribution of the homebound chronically ill in the different censal areas of Raval Nord was connected to 3 variables which, in order of analysis, were: distance to the PCC, the relationship with senile dependency and the index of family socio-economic capacity. CONCLUSIONS: Distance, senile dependence and economic resources are factors which condition the number and distribution of the homebound chronically ill.

Adolescent↗
PubMed1978

Geographical distribution of the dermatophytes: a review.

In these days of rapid transit from continent to continent, and the increasing mobility of people, agents of disease are no longer geographically restricted. Disease contracted half way across the world may become manifest in a country in which the pathogen is not normally found. Thus knowledge of the geographical distribution of pathogens becomes increasingly important when a diagnosis is being made. This is as true of ringworm fungi as of any other group of microorganisms. In the last 12 years, in the Mycological Reference Laboratory, an increasing number of exotic dermatophytes have been seen, related in part at least to the great increase in the number of non-British residents. Not all species of dermatophytes are cosmopolitan in their distribution throughout the world. While some have been recorded from every continent, others have geographically limited areas of greater or lesser extent. Surveys taken at intervals in a country may show a rise and fall in occurrence of several species as habits change, populations move and medical facilities became increasingly well-distributed. There have been few geographical surveys of ringworm fungi that have covered the world. Ajello (1960, 1974) has reviewed the individual species with regard to geographical location, while Vanbreuseghem & de Vroey (1970) attempted to estimate the relative importance of the various species in terms of numbers of isolations reported. This paper therefore reviews the world dermatophyte flora in terms of the dominant agents in the various countries, and some of the changes that have been recorded.

Africa↗
PubMed2000

Geographic distribution of human immunodeficiency virus-associated Pneumocystis carinii pneumonia in San Francisco.

The epidemiology of Pneumocystis carinii pneumonia (PCP) and its geographic distribution are incompletely understood. We examined the influence of geographic location as a risk factor for PCP through a retrospective case-control study of HIV-infected persons evaluated for PCP at San Francisco General Hospital. Subjects had microscopically confirmed PCP diagnosed between January 1996 and June 1999. Control subjects had a presentation suggestive of PCP, but had bronchoalveolar lavage examination that did not reveal P. carinii. Medical chart review was performed to obtain demographic and clinical characteristics of the subjects as well as their addresses at time of PCP evaluation. Multivariate analyses were performed in order to identify variables associated with PCP. Lack of P. carinii prophylaxis and a CD4 cell count </= 50 cells/microl were independent predictors of an increased risk of PCP. Interestingly, subjects living in the 94103 zip code had a significantly lower risk of PCP than subjects in other areas (odds ratio = 0.2, 95% confidence interval 0.1-0.6, p < 0.01). This effect was present despite controlling for risk factors for PCP such as use of prophylaxis or antiretroviral therapy, CD4 cell count, and HIV RNA level. We conclude that residence in the 94103 zip code of San Francisco is associated with a substantially lower risk of PCP than residence in other areas of the city.

AIDS-Related Opportunistic Infections↗
PubMed2000

Evolutionary consequences of changes in species' geographical distributions driven by Milankovitch climate oscillations.

We suggest Milankovitch climate oscillations as a common cause for geographical patterns in species diversity, species' range sizes, polyploidy, and the degree of specialization and dispersability of organisms. Periodical changes in the orbit of the Earth cause climatic changes termed Milankovitch oscillations, leading to large changes in the size and location of species' geographical distributions. We name these recurrent changes "orbitally forced species' range dynamics" (ORD). The magnitude of ORD varies in space and time. ORD decreases gradual speciation (attained by gradual changes over many generations), increases range sizes and the proportions of species formed by polyploidy and other "abrupt" mechanisms, selects against specialization, and favor dispersability. Large ORD produces species prone neither to extinction nor gradual speciation. ORD increases with latitude. This produces latitudinal patterns, among them the gradient in species diversity and species' range sizes (Rapoport's rule). Differential ORD and its evolutionary consequences call for new conservation strategies on the regional to global scale.

Biological Evolution↗
PubMed2001

Geographical distribution of Biomphalaria snails in the State of Minas Gerais, Brazil.

Published and unpublished observations on geographical distribution of Biomphalaria snails in the State of Minas Gerais, Brazil, were compiled. This work is aimed at knowing the present occurrence of Biomphalaria species in this region, and at contributing to the elaboration of the planorbid chart of Minas Gerais. In malacological surveys, performed by several researchers, the presence of seven species of this genus was recorded. Those planorbids were found in 12 mesoregions, in 283 (33.1%) municipalities out of 853 with the following distribution: B. glabrata (185 municipalities), B. straminea (125), B. tenagophila (58), B. peregrina (57), B. schrammi (26), B. intermedia (20) and B. occidentalis (2). B. glabrata and B. tenagophila are found naturally infected by Schistosoma mansoni in Minas Gerais. In 24 municipalities the three snail hosts of S. mansoni in Brazil, B. glabrata, B. tenagophila and B. straminea, are present.

Animals↗
PubMed1998

Geographical distribution of tuberculosis notifications in national surveys of England and Wales in 1988 and 1993: report of the Public Health Laboratory Service/British Thoracic Society/Department of Health Collaborative Group.

BACKGROUND: The geographical distribution of tuberculosis in England and Wales and changes since 1983 were examined using data from the 1988 and 1993 national surveys of tuberculosis notifications. METHODS: Notification rates for England and Wales in 1988 and 1993 were calculated for geographical areas using Office for National Statistics (ONS) mid year population estimates. Those for the standard regions and the Greater London boroughs were calculated for the main ethnic groups. Those for the counties and local authorities were calculated for all ethnic groups combined. These were compared using data from the 1983 national survey as a baseline. RESULTS: Wide regional variations in notification rates persist with Greater London having the highest rates. Rates in the ethnic group from the Indian subcontinent (ISC) were high in all regions, whilst those of the white ethnic group varied fourfold. Twenty seven of the 33 London boroughs showed increased rates in 1993 compared with 1988. In general, those local authority areas with high rates had high proportions of notifications in individuals of ISC ethnic origin, emphasising the continuing important contribution of ethnic minority groups to local tuberculosis rates. The number of local authority areas with notification rates four times the national average increased, but the number of areas with low or zero rates increased even more. CONCLUSIONS: The distribution of tuberculosis in England and Wales continues to vary markedly by geographical area. The distribution is becoming increasingly polarised with a growth in the number of areas with very high rates of notifications and a greater increase in the number of areas with very few notifications. Patients from ethnic minorities continued to contribute a substantial and increasing proportion of all reported tuberculosis cases in most regions in 1988 and 1993. These findings have important implications for the provision of tuberculosis services in England and Wales.

Demography↗
PubMed2002

Geographical distribution (2000) and temporal trends (1981-2000) of brominated diphenyl ethers in Great Lakes hewing gull eggs.

Geographical distribution of brominated diphenyl ether (BDE) flame retardants in the North American Great Lakes ecosystem in 2000 was determined by analysis of herring gull eggs (13 egg pools) from a network of 15 monitoring colonies scattered throughout the lakes and connecting channels. sigmaBDEs were found at concentrations ranging from 192 to 1,400 microg/kg, mean of 662 +/- 368 microg/kg (wet weight of egg contents). Highest concentrations were found in northern Lake Michigan and Toronto harbor (1,000-1,400 microg/kg) and lowest in Lake Huron and Lake Erie (192-340 microg/kg). The distribution suggested that input from large urban/ industrial areas through air or water emissions contributes local contamination to the herring gull food web in addition to background levels from regional/global transport. The congener composition was similar among sampling sites. Major congeners were BDE-47 (43%), BDE-99 (26%), BDE-100 (13%) BDE-153 (11%), BDE-154 (4%), BDE-183 (2%) and BDE-28 (1%). Temporal trends of BDE contamination, 1981-2000, were established by analysis of archived herring gull eggs (10 egg pools) from colonies in northern Lake Michigan, Saginaw Bay, Lake Huron and eastern Lake Ontario. BDE-47, -99 and -100, and BDE-153, -154 and -183 concentrations were grouped separately for analysis because these two groups had different trends and are primarily associated with the Penta BDE and Octa BDE flame retardant formulations, respectively. SigmaBDE47,99,100 concentrations were 5-12 microg/kg (wet weight) in 1981-1983 and then increased exponentially (p < 0.00001) at all three sites to 400-1,100 microg/kg over the next 17 years. Doubling times were 2.6 years in Lake Michigan, 3.1 years in Lake Huron and 2.8 years in Lake Ontario. SigmaBDE154,153,183 concentrations generally increased but varied in an erratic fashion among sites and decreased as a fraction of sigmaBDE over time. Concentrations of sigmaBDE154,153,183 were 100-200 microg/kg in eggs from all three colonies in 2000. Therefore, most of the dramatic increases in sigmaBDE concentrations observed over the past 20 years in the Great Lakes aquatic ecosystem seem to be connected with the Penta BDE formulation, which is mainly used as a flame retardant in polyurethane foam in North America. If present rates of change continue, concentrations of sigmaBDEs will equal or surpass those of sigmaPCBs in Great Lakes herring gull eggs in 10-15 years.

Animals↗
PubMed1998

Prevalence, incidence and geographical distribution of Johne's disease in cattle in England and the Welsh borders.

The prevalence, incidence and geographical distribution of clinical Johne's disease in dairy cattle in England and the border regions of Wales were determined by a postal survey of 3772 dairy farmers. The study area was divided into three regions; south, central and north. The response rate was 78.3 per cent. The proportion of farms that reported 'ever' having the disease was 17.4 per cent. For the 10 years between 1985 and 1994 it was 4.9 per cent, and only 1.5 and 1.3 per cent in 1993 and 1994 respectively. The highest prevalence figures were always in the south. The incidence rate of clinical disease was 3.0/10,000 cow-years in both years in all herds and 16.7 and 22.8/1000 cow-years in infected herds in 1993 and 1994 respectively. An estimate of the criterion validity of diagnosis by farmers was obtained by comparing the reporting of the clinical signs with positive veterinary or veterinary investigation centre diagnoses. The proportion of farmers reporting one or other of the correct clinical signs was 95.3 per cent, and 70.6 per cent reported both correct signs (diarrhoea and weight loss).

Animals↗
PubMed1976

Consideration of an association between geographic distribution of caves and occurrence of rabies in foxes.

Establishing a causative relationship for the association between geographic distribution of caves and the occurrence of rabies in foxes in the United States will require the demonstration of a plausible biological mechanism and proof from carefully designed epidemiologic studies. Considerable data implying biological plausibility exists in the form of rabies as an enzootic disease in bats, bat predation by ground animals, bat migratory patterns, and several possible virus transmission routes to the fox. Further data showing development of rabies in the fox following appropriate bat contact are needed. Evidence leading to the acceptability of a causal relationship should distinguish between spurious, causal, and indirect hypotheses. An alternative hypothesis is whether cave areas are superior fox habitats and harbor far greater populations of foxes than do noncave areas.

Animals↗
PubMedDate not supplied

[Geographical distribution and time trends in avoidable mortality in Catalonia, Spain (1986-2001)].

OBJECTIVES: To analyze time trends and geographical variation in avoidable mortality by health areas in Catalonia. MATERIAL AND METHODS: Avoidable mortality was analyzed according to the classification used by the Health Department of the Regional Government of Catalonia from 1986-2001 for health areas and causes were grouped as treatable and preventable. Standardized mortality rates were calculated by the direct and indirect method and the comparative mortality figures were calculated for the treatable and preventable groups and for the 46 health areas. The mean annual change adjusted for age was also calculated using a Poisson regression of avoidable and general mortality. RESULTS: The total number of avoidable deaths was 61,261 (7.3% of overall deaths). 10,623 cases (17.34%) were classified as treatable and 50,638 (82.65%) as preventable. The mean annual change for avoidable causes was -2.43% (95% CI, -2.60 to -2.26), higher than the -1.57% (95% CI, -1.61 to -1.52) change for general mortality. The rates were higher for preventable causes than for treatable causes, although mortality decreased in both groups. The health area of Segrià was notable for its significantly higher mortality from both treatable and preventable causes in both periods. Four health areas showed a significant increase in mortality from preventable causes but none showed an increase in mortality from treatable causes. CONCLUSIONS: In Catalonia, the decrease in avoidable mortality was greater than that in general mortality from 1986 to 2001. The geographical distribution shows wide dispersion but allows areas requiring preventive interventions to be identified.

Adolescent↗
PubMed1995

Prevalence, geographical distribution and clinical manifestations of onchocerciasis on the Island of Bioko (Equatorial Guinea).

A survey for the prevalence, geographical distribution and clinical manifestations of onchocerciasis was conducted on the Island of Bioko (formerly Fernando Póo), Equatorial Guinea, between 1987-89. The whole population (1799 inhabitants) of thirteen villages distributed around the island was surveyed. Identification data, physical examination and Snellen "E" test for visual acuity were performed. Skin snips were taken from both iliac crests and right scapula and calf. Differential diagnosis between Onchocerca volvulus and Mansonella streptocerca was carried out in both fresh and Giemsa stained preparations. The overall prevalence (+ skin snips) and mean microfilarial density were 75.2% (range 51.9% to 87.1%) and 32.2 mf/snip respectively. Skin snips showed a higher microfilarial density from iliac crests. The following clinical manifestations were found: 560 (31.2%) with nodules; 518 (28.8%) with dermatitis, pigmentation changes and cutaneous atrophy; 753 (41.9%) with lymphoadenopathy and lymphoedema. Blindness due to different causes was registered in 13 cases (0.8%). The results showed that onchocerciasis is hyperendemic and widespread over the island. It is estimated that almost the whole population (62,000) is at risk of infection.

Adolescent↗
PubMed1997

Geographic distribution and regional origin of 272 cystic fibrosis mutations in European populations. The Biomed CF Mutation Analysis Consortium.

The geographic distribution of 272 cystic fibrosis (CF) mutations has been studied by assessing the origin of 27,177 CF chromosomes from 29 European countries and three countries from the North of Africa. The most common mutations are delta F308 (66.8%), G542X (2.6%), N1303K (1.6%), G551D (1.5%) and W1282X (1.0%). The delta F508 mutation has the highest frequency in Denmark (87.2%) and the lowest in Algeria (26.3%). Mutation G542X is common in the Mediterranean countries, with a mean frequency of 6.1%. N1303K is found in most of the western and Mediterranean countries and has the highest frequency in Tunisia (17.2%). The wide distribution of these mutations suggests an ancient origin. G551D is common in north-west and central Europe, but is uncommon in other parts of Europe. W1282X has the highest frequency in Israel (36.2%), being also common in most Mediterranean countries and north Africa. Seventeen mutation have frequencies between 0.1 and 0.9%, 1717-1G-->A (0.83%), R553X (0.75%), R1162X (0.51%), 621 + 1G-->T (0.54%) and 2183AA-->G (0.36%), being the most common ones. Some mutations reach relatively high frequencies in some extended geographic regions, such as mutation 394delTT in northern Europe (1.1-28.8%), R117H in northwestern Europe (1.3-3.0%), R553X in central Europe (1.1-24.4%), 1717-1G-->A in Belgium and France (1.1-5.3%), and 2183AA-->G in Italy and Greece (3.2%). Other mutations are only common in small regions: T338I (Sardinia), 711 + 1G-->T (Tunisia), R1162X (Algeria and north of Italy), 1609delCA (east of Spain), 1811 + 1.6kbA-->G (southeastern Spain), R1066C (Portugal), S549R (Algeria), R334W (Crete), 621 + 1G-->T (Central Greece), 3849 + 10kbC-->T (Israel), 2789 + 5G-->A (south of Greece), 451 + 1G--A (Israel), R347P (south of Bulgaria), 1677delTA (south of Bulgaria and Turkey), G85E (south of Greece), R347H (Turkey), 3905insT (Switzerland), 1078delT (Brittany), 1898 + 1G-->A (Wales), A455E (The Netherlands), delta I507 (Brittany), 3659delC (Sweden) and R560T (northern Ireland). Most of these mutations must have an origin and diffusion in the specific European population subgroup. Overall 55 mutations are common in one or several countries or regions of Europe and 217 mutations are rare with relative frequencies of lower than 1% in any of these regions and countries. This information might facilitate mutation analysis of CF in the different regions of Europe.

Africa, Northern↗
PubMed2007

Contrasting geographic distribution profiles of the herpes simplex virus type 1 BgOL and BgKL variants in Japan suggest dispersion and replacement.

Thelifelong latent infection-reactivation mode of infection of herpes simplex virus type 1 (HSV-1) transmitted by close contact has allowed a diversity of restriction fragment length polymorphism (RFLP) variations to accumulate in human populations. Whether and how the variants of the HSV-1 that is ubiquitous worldwide spread to different human populations is not clear. In our previous study the geographically gradient distribution of the HSV-1 BgK(L) variant, which is a good marker for the BgK(L):SaCFJ(M):SaGH(M):SaD/E(L):KpM(S) variant, suggested that BgK(L) dispersed geographically. Southern hybridization analyses showed that in BgK(L) the BglII cleavage site between the BglII K and small "Q/#13" fragments is lost, the SalI cleavage sites between the SalI J and C and between SalI F and J fragments are lost, and the SalI E fragment is abnormally large (SaE(L) variation). The RFLP and geographic distribution of one more HSV-1 RFLP variant, BgO(L), were comparatively analyzed. The BglII cleavage site between the BglII O and Q/#13 fragments is lost in BgOL. BgO(L) clinical isolates were not associated with any of the SaCFJ(M), SaE(L), SaGH(M), or KpM(S) variations, whereas one-fourth of the non-BgO(L):non-BgK(L) isolates was associated with SaCFJ(M) and SaGH(M), indicating that BgK(L) and BgO(L) are distant in terms of diversification. BgO(L) is distributed highly in the northeastern region and the southwestern island of Kyushu but is rare between the two regions in Japan, in a remarkable contrast to BgK(L). These are the first epidemiologic data to show contrasting geographic distribution profiles of two HSV-1 variants and suggest the gradual dispersion and replacement of HSV-1 variants.

Bacterial Proteins↗
PubMedDate not supplied

[Geographical distribution of mortality from malignant pleural neoplasms and of former asbestos-exposed workers in the Campania Region].

AIM: The purpose of the present paper is to describe the geographical distribution at municipality level of mortality from malignant pleural neoplasms in the Campania Region, along with the distribution of former asbestos-exposed workers. A GIS (Geographical Information System) application has been developed to integrate exposure and mortality data. STUDY DESIGN: The number of asbestos workers by municipality has been estimated by merging data provided by the National Institute for Insurance against Occupational Accidents (INAIL), the Ministry of Labour and an association of formerly exposed workers (AUSER Flegrea). The number of deaths from malignant pleural neoplasms by municipality has been derived from published studies regarding two consecutive periods: 1988-1994 and 1995-1997. RESULTS: In the first period most deaths occurred in areas with a high number of formerly exposed asbestos workers, whilst in the second period mesothelioma mortality increased extending to other areas without registered exposed workers. CONCLUSION: This finding may be attributable to the presence of atypical occupational exposures, not reported by the current information systems, or to environmental, non occupational exposure patterns.

Asbestos↗