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PubMed1991

The geographic distribution and host range of Capillaria hepatica (Bancroft) (Nematoda) in Australia.

The geographic distribution, host range and prevalence of Capillaria hepatica were recorded in 4629 house mice, Mus domesticus, 263 black rats, Rattus rattus, and 58 Norway rats, R. norvegicus. The parasite was found at five localities, all in or near large towns along the coast. The two Rattus species appeared to be the primary hosts of C. hepatica in Australia. Published and unpublished data on helminth infections of Australian native mammals from 1162 murids (26 species), 3018 marsupials (67 species) and 99 monotremes (two species) were compiled. Only seven animals from three murid species were infected with C. hepatica; all were from the same rainforest in northern Queensland. C. hepatica was distributed widely, occurring in the house mouse, black rat and Norway rat on a 10,850 ha farm but there was no infection in cattle, sheep or goats (abattoir records). Also, 52 rabbits, four cats and one fox (shot samples) and 27 marsupial mice, Sminthopsis crassicaudata (museum specimens), had no sign of C. hepatica infection. Overall, the results indicate that transmission of C. hepatica to native, domestic and feral mammals is rare, presumably because of ecological constraints on egg embryonation and survival. In the light of these findings, the potential use of C. hepatica as a biological agent to control mouse plagues in Australia is discussed.

Animals↗

PubMed2001

A cost-minimization approach to planning the geographical distribution of health facilities.

This paper illustrates a method of planning the geographic distribution of health facilities in order to maximize the social benefits achievable from the investment. Data from Bangladesh have been used to determine the optimal distribution of emergency obstetric care (EOC) facilities in the country using the estimates of average social cost per woman. Costs incurred by households, including the costs associated with maternal mortality, tend to increase with increasing radius of a facility's catchment area. The average facility-based costs tend to decline with increasing radius due to lower per capita capital expenditures. The summation of these two average cost functions generates a U-shaped curve. In this research, the minimum point of the aggregated average cost curve defines the 'optimal' radius of a health facility. The catchment area defined by the optimal radius minimizes the average social cost of providing EOC services in a region. The empirical analysis suggests that the optimal radius for the 20 regions of Bangladesh varies from about 6 to 12 km. If the optimal radius of the catchment area is used in planning health centre locations, Bangladesh will need to set up 450 EOC facilities; currently there are only 90 such facilities.

Bangladesh↗

PubMed1999

Accidental out-of-hospital births in Finland: incidence and geographical distribution 1963-1995.

BACKGROUND: The study aims to describe the incidence and geographical distribution of accidental out-of-hospital births (accidental births) in Finland in relation to the changes in the hospital network, and to compare the perinatal outcomes of accidental births and all hospital births. METHODS: Data for the incidence and distribution analyses of accidental births were obtained from the official statistics between 1962 and 1973 and from the national Medical Birth Registry (MBR) in 1992-1993. The infant outcomes were analyzed for the MBR data in 1991-1995. RESULTS: Between 1963 and 1975 the central hospital network expanded and by 1975 they covered 72% of births. The number of small maternity units has decreased since 1963. The incidence of accidental births decreased between 1963 and 1973, from 1.3 to 0.4 per 1000 births, and rose by the 1990s to 1/1000. In the 1990s the parity adjusted risk of an accidental birth was higher for residents of northern than of southern Finland, OR 2.51 (CI 1.75-3.60), and for residents of rural compared to urban municipalities, OR 3.26 (CI 2.48-4.27). The birthweight adjusted risk for a perinatal death was higher in accidental births than in hospital births, OR 3.11 (CI 1.42-6.84). CONCLUSIONS: A temporal correlation between closing of small hospitals and an increase in accidental birth rates was detected. Due to the poor infant outcomes of accidental births, centralization policies should include measures to their prevention.

Adult↗

PubMed1991

Geographical distribution of the subgenus Helcocyrtomyia, genus Lutzomyia (Diptera: Psychodidae--Phlebotominae).

The known geographical distribution of species included in the subgenus Helcocyrtomyia Barretto is reviewed. It is suggested that the vexator series of the subgenus originated in the Nearctic Region and extended southwards along the Andes (peruensis series) whereas the oswaldoi series is a South American assemblage originating in Gondowana. It is concluded that Helcocyrtomyia cannot be accepted as a monophyletic group.

Americas↗

PubMed1983

Geographical distribution of lung and stomach cancers in South Africa, 1968-1972.

The geographical distribution of lung and stomach cancer among three races in South Africa (Whites, Coloureds and Asians) has been investigated for the years 1968-1972, and the patterns of the occurrence of cases of cancer have been tested stochastically and mapped both separately and together. Information was not available for the Black population. Distinct differences in the distribution of lung and stomach cancer were found. Possible explanations for these differences are discussed.

Black or African American↗

PubMed1981

A review of Simulium damnosum s.l. and human onchocerciasis in Nigeria, with special reference to geographical distribution and the development of a Nigerian national control campaign.

The confirmed geographical distribution of human onchocerciasis and its Simulium damnosum complex vectors in Nigeria is reviewed with the aim of defining the endemic zones of the disease relevant to the planning of a Nigerian national onchocerciasis control campaign. Five major endemic zones are recognized, a terminology suggested for them, their sizes estimated and the disease and vector situation within each zone briefly described; four of the zones are in savanna areas of the north, and the fifth in forest-savanna mosaic and forest areas of the south-west. Other areas where disease and/or vectors have been reported are briefly considered. Maps are given of known vector breeding sites, of disease distribution, and of the approximate extent of the anticipated control zones. The scanty available data on cytospecies identity of the vectors, vector biting rates, and Onchocerca volvulus transmission potentials, are reviewed, and it is stressed that acquisition of distributional data for the individual members of the S. damnosum complex and of ATP data is essential for the planning of control. An historical resumé, accompanied by a comprehensive bibliography of the published literature, of the work to date in Nigeria is included.

Animals↗

PubMed2002

[Magnitude, geographic distribution and trends of anemia in preschoolers, Brazil].

OBJECTIVE: To assess the magnitude, geographical distribution and trends of the prevalence of nutritional anemia among preschoolers and to identify risk groups in the state of Paraiba, Brazil. METHODS: A cross-sectional survey with multistage random sampling procedure was conducted in 8 urban municipalities of three mid-regions (Zona da Mata, Agreste and Sertão) in the state of Paraíba in 1992. A total of 1,287 preschoolers of both sexes were selected. Hemoglobin was determined by the cyanometahemoglobin method in venous blood, employing <11 g/dl as the cut-off for anemia. Statistical analysis of proportions employed the chi Square test, whereas for means Mann-Whitney and Kruskal-Wallis were the choice, all with confidence interval of 95%. RESULTS: The prevalence of anemia was 36.4% (CI 33.7 - 39.1) in the state of Paraiba, greater (p=0.00) than that observed (19.3%, CI 17.3 - 21.5) in 1982. Only 1.0% (CI 0.61 - 1.8) and 6.8% (CI 5.5 - 8.3) of anemia cases were classified as severe and moderate, respectively. Boys presented lower mean hemoglobin concentration (p=0.00), and children under age 3 comprised the biological group of highest susceptibility for deficiency status (p= 0.00). It was found that the second year of life is the most critical for developing nutritional deficiency (p= 0.00). The Agreste mid-region revealed to be the geographical area of highest risk (p= 0.00), outlining a new epidemiological dynamics when compared to the year 1982, when the drought-ridden Sertão region were the geographical area at greatest risk of deficiency. CONCLUSIONS: According to international epidemiological criteria, anemia in the studied regions represents a public health problem of moderate degree Assuming the analytical comparability of the 1982 and 1992 cross-sectional surveys, it suggests an increasingly prevalence of nutritional anemia (+88.5%) in all 3 mid-regions in a 10-year-period (1982-92).

Anemia, Iron-Deficiency↗

PubMed1989

The potential geographical distribution of the Old World screw-worm fly, Chrysomya bezziana.

The potential geographical distribution and relative abundance of the Old World screw-worm fly, Chrysomya bezziana Villeneuve (Diptera: Calliphoridae) as determined by climate, was assessed using CLIMEX, a computer program for matching climates. CLIMEX describes the relative growth and persistence of animal populations in relation to climate. The observed global distribution of C.bezziana was compared with the potential distribution predicted by CLIMEX. The differences in the two distributions indicate the areas at risk of colonization, with particular reference to Australia and the Americas. According to the model, the potential area of permanent colonization in Australia extends south to the mid-coast of New South Wales. Comparison of areas suitable for permanent establishment with the potential summer distribution indicates that large additional areas, carrying most of the continent's livestock, could be colonized in the summer months. Seasonal population growth indices are presented for three ports in Australia at which screw-worm fly specimens have been collected by quarantine authorities. They indicate the relative risk associated with introductions at different places in different seasons and so provide valuable planning information for quarantine authorities. The CLIMEX predictions for C.bezziana in North America are shown to be similar to the recorded distribution limits of the New World screw-worm fly, Cochliomyia hominivorax (Coquerel). The fly could also colonize South America, as far south as southern Brazil and midway through Argentina.

Animals↗

PubMed1993

A geographical distribution of mortality and deprivation.

Because of the paucity of data on the geographical distribution of mortality and deprivation in the Republic of Ireland, we calculated SMRs for each county for the years 1982-6. Two measures of mortality were used, all cause and avoidable mortality. Two indexes of deprivation were also calculated for each county, Townsend's and a new Irish index. Significant differences in mortality exist between counties. Counties that had SMRs significantly below the national standard of 100 were Meath, Donegal and Galway. Counties with significantly high SMRs were Louth, Limerick and Westmeath. County SMRs were correlated with both deprivation indexes and no significant correlation was found to explain the apparent differences in mortality.

Educational Status↗

PubMed1981

Gene flow and the geographical distribution of a molecular polymorphism in Drosophila pseudoobscura.

This paper discusses the relation between the geographical distribution of an enzyme polymorphism and population structure in Drosophila pseudoobscura. California populations of this species living in very different montane and lowland habitats separated by several kilometers are similar to each other in the frequency of an esterase allele. Previous estimates suggest that gene flow is too limited to account for this homogeneity of genetic structure, so that it must reflect some balancing force of natural selection. We slow, however, that dispersal over unfavorable habitats is much greater than earlier supposed. Isolated populations of D. pseudoobscura separated by 15 km from other populations are subject to large amounts of immigration. This is shown by changes in the seasonal abundance of this species and in the annual pattern of lethal alleles in such populations. The genetic structure of an experimentally perturbed isolated population in an oasis returned to normal within a single year, suggesting that such populations are ephemeral and that the oasis is subject to annual recolonization by distant migrants. Direct assessment of marked flies shows that they can move at least 10 10 km in 24 hours over a desert. Such extensive gene flow may help explain the distribution of the esterase allele, and is relevant to the high level of molecular polymorphism and its general lack of geographic differentiation throughout the range of D. pseudoobscura.

Alleles↗

PubMed1995

Geographical distribution of the Hbb haplotypes in the Mus musculus subspecies in eastern Asia.

We surveyed the geographical distribution of Hbb haplotypes of the house mouse, Mus musculus, in the former USSR and the northern part of China. Mice with the w1 haplotype were distributed from the coastal area of the Black Sea to the Maritime Province of Siberia in the former USSR and in the area north of the Yangtze River in China. Mice with the p haplotype were found in the areas surrounding those populated with the w1 haplotype mice. In the Maritime Province and the southern part of Siberia, the d haplotype was predominant. The correlation between the geographical variation of the Hbb haplotypes and the distribution of the Mus musculus subspecies in the eastern part of the Eurasian Continent, is discussed.

Animals↗

PubMed1997

[The trends and geographical distribution of breast cancer mortality in Andalusia (1976-1995)].

OBJECTIVE: To describe trends and geographical distribution of breast cancer mortality in Andalusian women between 1976 and 1995. DESIGN: Descriptive study. SETTING: Andalusia. PATIENTS AND OTHER PARTICIPANTS: Deaths from breast cancer during the period 1976 to 1995 were obtained. MEASUREMENTS AND MAIN RESULTS: The following were calculated: crude mortality rates; age-adjusted rates by the direct method, using the European population as standard; rates broken down for 15-44, 45-64 and over 65 age-groups; accumulated rates for 0 to 74 years; age-adjusted rates of potential years of life lost (PYLL); specific rates for five-year age groups for each of the five-year periods studied. Between 1976 and 1995 breast cancer mortality in Andalusian women almost doubled in absolute terms. Age-adjusted rates went up by 40.31%; the rates broken down increased, especially those for over-65s, while the 15 to 44 and 45 to 64 groups also went up, as did the PYLL rates. CONCLUSIONS: Breast cancer in Andalusia is a growing health problem, concentrated in very concrete geographical areas. It needs a determined health intervention in order to detect it early and avoid the deaths it is causing.

Adolescent↗

PubMed1984

[Geographic distribution of Ancylostoma duodenale and Necator americanus in Taiwan].

In order to determine the geographical distribution of Ancylostoma duodenale and Necator americanus in Taiwan, 2,759 fresh stool samples were collected from 5th-grade school children of both sexes among 43 preliminary schools in 16 counties, and then examined by means of the modified test-tube filter-paper cultivation method for identification of the filariform larvae of hookworm. Both species of A. duodenale and N. americanus are widespread in Taiwan. The overall infection rate was 20.00%. The rate of A. duodenale, N. americanaus and mixed infection of both species was 9.85%, and 7.75% and 2.39% respectively. Geographically, N. americanus (12.64%) predominated over A. duodenale (5.43%) in the north (Ilan, Taipei, Taoyuan, Hsinchu and Miaoli) and the east (Taitung) areas. On the contrary, A. duodenale (13.40%) predominated over N. americanus (5.63%) in the central (Nantou, Taichung, Changhua and Yunlin), the south (Chiayi, Tainan, Kaohsiung and Pingtung) and the east (Hualien) areas. On the other hand, the rate of infection on the offshore island (Penghu) was much lower (1.19%) than the others (21.10-21.29%).

Ancylostomiasis↗

PubMedDate not supplied

[Geographical distribution of the male/female ratio of cardiovascular mortality in Spain].

OBJECTIVES: To describe the geographic distribution of the male/female ratio (MFR) of mortality from ischaemic heart disease (IHD) and cerebrovascular disease (CVD) in 1991-1995 in Spain, and to examine wether the differences between men and women in exposure to cardiovascular risk factors could explain such distribution. METHODS: Mortality data come from National Vital Statistics. Age-adjusted mortality rates for the period 1991-1995 were calculated for IHD and CVD using the direct method, in population aged 40 to 79 years. Data on tobacco and alcohol consumption, hypertension, hypercholesterolemia, diabetes, obesity, sedentariness, and health services use come from the 1993 Spanish National Health Survey, and socioeconomic data from the 1991 Population Census. Data were analyzed by correlation and Poisson regression methods. RESULTS: MFR of mortality from IHD and CVD are higher in the provinces of the north of Spain, and are correlated negatively with mortality from IHD and CVD. This negative association is stronger for mortality in women than in men. Among the risk factors examined, only MFR of alcohol consumption showed a significant (p < 0.05) association with MFR of mortality from IHD and CVD. MFR of alcohol consumption explains 23 and 14% of the provincial variation in MFR of mortality from IHD and CVD, respectively, and showed a U shaped relationship with MFR of mortality for both diseases. CONCLUSIONS: Provinces in the north of Spain, which register the lowest cardiovascular mortality, show the highest MFR of IHD and CVD mortality, because of the lower mortality in women than in men. As derived from the dose-response relationship between MFR of IHD and CVD mortality and the MFR of alcohol consumption, a higher alcohol consumption in men could contribute to a higher MFR of cardiovascular mortality in some Spanish provinces.

Adult↗

PubMed1998

Increasing geographical distribution and density of Ixodes ricinus (Acari: Ixodidae) in central and northern Sweden.

The geographical distribution and density of Ixodes ricinus (L.) in the 2 northern regions, Svealand and Norrland, in Sweden were studied by using a questionnaire in Swedish magazines for house owners and dog owners, and in provincial newspapers. Analysis of the approximately 1,200 answers revealed that ticks are present in all parts of Svealand (except northern Värmland and northern and western Dalarna), the southeastern part of Norrland (i.e., Gästrikland and Hälsingland), and along the Baltic Sea coast of central and northern Norrland. The proportion of answers reporting ticks and the estimated tick density (i.e., the number of ticks infesting dogs and cats) decreased from south to north. The answers to the questionnaire and data from field sampling of ticks suggest that tick density decreased distinctly along a narrow boundary zone, coinciding with the biological limit of Norrland (Limes Norrlandicus), crossing Sweden through southern Värmland, southeastern Dalarna, and central Gästrikland. The results of the questionnaire suggest that I. ricinus ticks are more widespread today than in the early 1980s, especially in Värmland, western and central Dalarna, Hälsingland, and the coastal areas of Medelpad, Angermanland, and Västerbotten, and that the proportion of the human population at risk for tick-borne pathogens in Svealand and Norrland is increasing.

Animals↗

PubMed1987

Geographical distribution, preoperative orthodontics, and morbidity of Norwegian patients surgically treated for mandibular prognathism.

The geographical distribution of 1169 Norwegian patients operated on for mandibular prognathism during the years 1975-1984 showed an accumulation of cases in the western and northern parts of the country. This skew distribution was probably due to genetic factors. No association was found between the number of operated patients and the number of orthodontists or oral and maxillofacial surgeons in the different counties. Most of the patients (69%) had less than 2 years and 10% had more than 4 years of preoperative orthodontic treatment. The use of presurgical orthodontics seemed to increase during the observation period, and the mean treatment time was shorter in the last half of the decade. The morbidity, defined as the duration of the hospital stay and the intermaxillary fixation period, was on an average 56 days, mostly dependent on the surgical unit.

Adult↗

PubMed1992

The geographic distribution of measles in the United States, 1980 through 1989.

OBJECTIVE: To describe the geographic distribution of measles cases in the United States by county for the 10-year period from 1980 through 1989. DESIGN: Ecological analysis of national measles surveillance data. METHODS: Measles cases reported to the Morbidity and Mortality Weekly Report from 1980 through 1989 were analyzed. Data from the 1980 and 1990 US censuses were used to produce demographic profiles for each of the 3137 countries. Outcome variables examined included mean annual incidence and number of years reporting measles, with use of Spearman's rank correlation coefficients to examine the association between the demographic and the two outcome variables. RESULTS: A total of 56,775 measles cases were reported during the decade. Of the nation's 3137 counties, 1690 (53.9%) did not report any cases; only 17 (0.5%) reported measles in all 10 years. Counties reporting measles more frequently during the decade had higher median populations, population densities, and percentage of black and Hispanic populations than those counties reporting less frequently. Population size, population density, and percentage of Hispanic population were associated with number of years reporting measles and mean annual measles incidence rate. Measles cases in counties reporting measles every year predominantly occurred in unvaccinated preschoolers; cases in counties reporting less frequently predominantly occurred in vaccinated school-aged children. CONCLUSIONS: This analysis illustrates the focal nature of measles in the United States during the past decade. Most counties have not reported a single case of measles during the entire decade, and only 17 counties reported measles every year. Targeted strategies are needed to improve age-appropriate immunization levels among preschool-aged children living in large inner-city areas.

Adolescent↗

PubMed1979

[Geographic distribution in some latin countries of cancers of the alimentary tract (author's transl)].

Geographic distribution in some latin countries of cancers of the alimentary tract. A comparison of alimentary tract cancer incidence rates has been undertaken from the results of 5 latin cancer registries. The most striking features are the high incidence rates for gastric cancers in the provinces of Zaragoza and Piemont, for colorectal cancers in the canton of Geneva, and in the countries of Côte-d'Or and Bas-Rhin. Tumour localization in the large bowel differs significantly between Geneva and the French counties. The canton of Geneva has the highest rate for cancer of the pancreas, French countries for cancer of the oesophagus in males. Sex ratio for primary cancer of the liver differs considerably from one region to another.

Digestive System Neoplasms↗