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PubMed1997

Geographical distribution of vectors and sero-strains of tsutsugamushi disease at mid-south inland of Korea.

Studies of geographical distributions and relative population densities of the vector mites of tsutsugamushi disease were carried out in October 1996 at 12 locations of the mid-south inland of the Korean peninsula, where chigger mites have been never studied. Of 177 field rodents and insectivores collected, 154 (87.0%) were Apodemus agrarius. Total 25,707 chigger mites were collected and 14 species were identified, of which Leptotrombidium pallidum was predominant (79.8%) and L. palpale the next (8.9%). L. pallidum, the vector species, was widely distributed in all study areas, showing the highest density at Cho-o 2-dong, Sangju-si (chigger index 201.8), and the lowest at Tanwol-dong. Chungju-si (chigger index 40.7). The other vector species, L. scutellare was found only at the southern part of the study area such as Yobae and Mipyong, Kumrunggun and Unsu, Kimchon-si. The northernmost areas of the L. scutellare distribution were coincided with the areas where anual mean air temperature is above 10.0 C. Among 157 A. agrarius sera tested, 48.3% was Karp, 1.7% Gilliam and 3.3% Kuroki. The rest of the sera were not able to determine the sero-type because of the cross antigen-antibody reactions among the tested sero-types.

Animals↗

PubMed1992

[Genetic differentiation of the Mongolian population. Comparative analysis of the geographic distribution of biochemical markers of genes and restriction fragment length polymorphism of nuclear DNA in the Mongolian population].

The geographical distribution of the gene frequencies from loci: Hp, Tf, Gc, Pi, AcP1, GLO1, EsD, 6-PGD, PGM1 and RFLP's of the nuclear DNA of the loci HBG-2 (HindIII), HBB (AvaII), ApoB (XbaI), D7S8 (PstI), LDLR (HincII) and AT-3 was analysed in the Mongolian population. These data revealed the homogeneity of 18 local groups in Mongolia and extremely low genetic differences measured by GST. There was no differences in the average GST values between protein markers and nuclear DNA markers.

Chromosome Mapping↗

PubMed2004

Health inequalities in Thailand: geographic distribution of medical supplies in the provinces.

The purpose of this study was to analyze the regional characteristics and geographic distribution of the medical staffs (physicians and nurses) and the patient beds in relation to the population and average death rates in each of the provinces in Thailand, by using the Lorenz curve and Gini coefficients. Those data were obtained from surveys conducted by the Ministry of Public Health and the Office of the National Education Commission. It was demonstrated that there are certain clear uneven distributions in medical personnel, especially physicians (Gini index = 0.433), by province. For physicians, nurses, and patient beds, approximately 39.6%, 25.8% and 20.6% are concentrated in the Bangkok Metropolis. Specific ideas to solve those problems are discussed in order to overcome this health care crisis by the year 2025.

Beds↗

PubMed1989

Geographical distribution and habitat preferences of the invader freshwater snail species Lymnaea columella (Mollusca: Gastropoda) in South Africa.

The present geographical distribution of Lymnaea columella, as recorded in the National Freshwater Snail Collection, is described and discussed. It appears that L. columella is the most successful colonist of all the freshwater snail species in South Africa, and, together with Bulinus tropicus and Lymnaea natalensis, it forms the most widely distributed freshwater snail species in the region. Data regarding the 2,341 discovery sites of L. columella recorded by collectors during surveys are analysed. L. columella cluster mainly in rivers or streams with perennial, slow flowing, or stagnant freshwater with many plants and a mud substrate. L. columella is regarded as a more effective intermediate host for the transmission of fascioliasis than the indigenous snail species. The economical implications of this are discussed briefly in the light of its success as an invader species.

Animals↗

PubMed1995

Explanatory factors for the geographic distribution of U.S. civil aviation mortality.

BACKGROUND: State-specific aviation-related mortality rates differ substantially between various geographical regions of the United States. PURPOSE: The purpose of this study was to ascertain important explanatory factors that account for the geographical distribution of mortality. METHODS: National Center for Health Statistics sources were used to calculate state-specific, age-adjusted mortality rates. Fatalities studied were those attributed to select civil aviation-related causes (ICD-9 E-codes 840.2-.6, 841.2-.6, 842.2-.6) that occurred from 1979-89. State-specific information on a variety of selected variables was obtained from census, commerce, and Federal Aviation Administration (FAA) sources. Multiple linear regression techniques were used to assess the relationship between selected variables and state-specific mortality rates. RESULTS: There were 13,048 deaths for a U.S. 11-year mean mortality rate of 4.9 deaths/1,000,000 general population. Mountainous states of the western U.S. had the highest 11-year mean mortality rates (range 8.6-79.6 deaths/1,000,000). Mid-Atlantic states had the lowest rates (range 1.6-2.9 deaths/1,000,000). Regression analysis identified pilot density (number of pilots per 1,000,000 general population), top elevation (highest point of land within state boundaries), and flight intensity (number of general aviation flight hours flown per pilot) as important factors in explaining 92% of state mortality differences. CONCLUSIONS: Highest aviation-related mortality rates are found in states with expanses of mountainous terrain, and relatively high pilot densities and flight activity levels.

Accidents, Aviation↗

PubMed1997

Geographic distribution, supply, and need for generalist physicians in Alaska.

This study provides the first comprehensive description of Alaska's geographic distribution of generalist physicians relative to population. All 443 generalist care physicians (family, general, general internal medicine, and pediatric) or their office managers were questioned about their specialties, ZIP codes, employers, populations served, and hours spent per week offering direct patient care. The results indicated a 30% overall shortage of generalist physicians for the state, representing roughly 141 full-time-equivalent generalists relative to national practice patterns and trends of health maintenance organizations. Of 17 primary health care areas, including the Anchorage area, 15 showed a need for additional generalist physicians. Most areas had a 20 to 40% shortage. Concerns about transportation and financial barriers to access to care, especially in remote regions, were raised. Other needs emphasized included knowledge of contributions of midlevel health care professionals, Alaska Native versus non-Native care, efforts to train and retain physicians in Alaska, and the need for longitudinal tracking of practice patterns.

Alaska↗

PubMed2001

[Geographic distribution of surnames and genetic structure: the county of Ardeche at the beginning of the twentieth century].

The analysis of the geographical distribution of surnames (whose transmission in the European societies is similar to that of the Y chromosome) allows to study in an exhaustive way the spatial and temporal human population structure and the influence of environmental variations on this structure. The genetic structure of the Ardèche county was analysed through a study of the surname characteristics (diversity, frequency, geographical dispersion, etc.) of individuals born between 1891 and 1915. The estimation of the intra-community average consanguinity and the inter-district genetic relationships reveals a clear differentiation between populations of the mountainous part (geographically isolated, highly inbred) and those of the Rhône valley (less isolated, weakly inbred). As predicted by the isolation by distance model, inter-population coefficients of kinship decreases as distance increases, confirming the presence of a spatial structure, characterized by neighborhood exchange and resulting from former migratory flow.

Alleles↗

PubMed2005

E. dispar strain: analysis of polymorphism as a tool for study of geographic distribution.

The intra-species polymorphism of E. histolytica and E. dispar species in endemic area is an important tool for geographic distribution and spread mechanism studies. Since E. dispar and E. histolytica shears ecological niche, cell cycle, and transmission mechanism for human host, we studied the intra-specie variation and distribution of E. dispar strains obtained from cyst passers, in two neighbor rural communities in Morelos Mexico. We analyzed the polymorphic region of the quitinase protein gene in isolates of E. dispar. In 45 isolates from one community we identified 12 different CHI patterns while in 15 isolates from the other community we identified 5 different patterns. However both communities share 4 patterns. This finding suggests the presence of strains with different geographic mobility.

Animals↗

PubMed1993

Geographical distribution of preconceptional radiation doses to fathers employed at the Sellafield nuclear installation, West Cumbria.

OBJECTIVE: To examine whether the geographical distribution of births associated with preconceptional exposure of fathers to radiation at the Sellafield nuclear installation is consistent with the suggestion that this exposure explains the excess of childhood lymphoid malignancy in the adjacent village of Seascale. DESIGN: Retrospective birth cohort study. SETTING: Cumbria, West Cumbria health district, and Seascale civil parish. SUBJECTS: The 10,363 children born in Cumbria during 1950-89 to fathers employed at Sellafield. MAIN OUTCOME MEASURES: The doses of external whole body ionising radiation received by fathers at Sellafield in the total time and in the six months before conception of their children; the proportions of the collective doses associated with Seascale and the rest of West Cumbria. RESULTS: 9256 children were born to fathers who had been exposed to radiation before the child's conception. Of these, 7318 had fathers who were exposed in the six months before conception. Overall 7% (38 person-Sv) of the collective total preconceptional dose and 7% (3 person-Sv) of the collective dose for the six months before conception were associated with children born in Seascale. Of all the children whose fathers worked at Sellafield, 842 (8%) were born in Seascale. The mean individual doses before conception were consistently lower in Seascale than in the rest of West Cumbria. CONCLUSIONS: The distribution of the paternal preconceptional radiation dose is statistically incompatible with this exposure providing a causal explanation for the cluster of childhood leukaemias in Seascale.

Adult↗

PubMed1982

[Study On Metagonimus Yokogawai (Katsurada, 1912) In Korea: VI.The Geographical Distribution Of Metacercarial Infection In Sweetfish Along The East And South Coast]

This study was carried out to outline the geographical distribution of the sweetfish which were infected by the metacercariae of Metagonimus yokogawai from August to October in 1979. The infection status was examined both by the muscle compression method and by digestion technique. The result was summarized as follows: 1. A total of 197 sweetfish, Plecoglossus altivelis was collected, 125 fish from 5 streams along the East Coast and 72 fish from 4 streams along the South Coast. 2. Total 125(63.5 %) fish were infected by the metacercariae of M. yokogawai. The rate and intensity of infection in the south coastal areas were much higher than those in the east coastal areas; the rate was 42.4 % in the East and 100 % in the South, mean number of metacercariae per fish was 721 in the East and 14,308 in the South, and mean number of metacercariae per gram of flesh was 43 in the East compare with 904 in the South. 3. The sweetfish infected by the metacercaria of M. yokogawai were newly observed in 5 foci, i.e., Yeongogcheon in Myeongju Gun and Namdaecheon in Gangneung Si, Gangweon Do and Wangpicheon in Uljin Gun, Gyeongsangbug Do in the East, and a branch of Namgang in Euiryeong Gun and Sinhyeoncheon in Geoje Gun, Gyeongsangnam Do in the South. The rate of metacercarial infection was 4.1 % in Yeongogcheon and 100 percent in others. The number of metacercariae in a fish ranged from 9 to 45,018 and the number of metacercariae per gram of flesh was the lowest in Gangneung Namdaecheon as 19 and the highest in Geoje Sinhyeoncheon as 1,237. Summarizing these findings with previous records, M. yokogawai might be prevalent in the streams along the East Coast southern from Myeongju Gun, Gangweon Do and along the South Coast in Korea.

Journal Article↗

PubMedDate not supplied

[The geographical distribution of women's health problems in Jalisco, Mexico].

The epidemiological studies on women's health, with relation to their geographical distribution (rural and urban), have focused on the areas of fertility and family planning. This work attempts to open up, to a worldwide level of comprehension, the perspectives of the problems related to women's health. It show the results of an investigation of two population groups of women, one in the rural zone, and the other in the urban zone; both groups were from the state of Jalisco, Mexico. The objectives were: to identify the more frequent health problems occurring in women and to establish the similarities and differences between these two female groups. The information was obtained by means of unique interviews using questionnaires. Sociodemographic variables, housing, and sanitation were studied, as well as a health questionnaire which was divided into apparatus and systems. Better sanitary conditions and more favorable sociodemographic indicators were found among women in the urban zone as opposed to those in the rural zone. The most frequent health problems are, in decreasing order, those located in the nervous, digestive, cardiovascular, and genital-urinary systems. There exists a direct relationship between the frequency of health problems and age. Generally, the women most affected are those in the rural zone. It is difficult to establish comparisons with the health conditions of women in other areas due to lack of research that makes differentiations with regard to sex (in this case, those focusing on women). We consider it of interest to continue with insightful investigations of chronic, degenerative, and deficiency problems, as well as those related to self-attention.

Female↗

PubMed1988

The prevalence, incidence, geographical distribution, antimicrobial sensitivity patterns and plasmid profiles of milk filter Salmonella isolates from Ontario dairy farms.

The prevalence, incidence and geographical distribution of Salmonella on dairy farms in southwestern Ontario were determined by culturing bulk milk filters from 511 randomly selected dairy farms. Milk filters from 22 farms (2.9%) were Salmonella-positive, with a cumulative incidence rate of 9.0% per year. Positive farms were distributed throughout southwestern Ontario, but were regionally clustered. The serotype, biotype, antimicrobial sensitivity pattern and plasmid profile of the Salmonella isolates from six farms where Salmonella were recovered on two occasions were identical. All of the Salmonella strains isolated were sensitive to commonly used antimicrobials.

Animals↗

PubMed2005

Geographic distribution of babesiosis among dogs in the United States and association with dog bites: 150 cases (2000-2003).

OBJECTIVE: To identify the geographic distribution of babesiosis among dogs in the United States and determine, for dogs other than American Pit Bull Terriers (APBTs), whether infection was associated with a recent dog bite. DESIGN: Retrospective study. ANIMALS: 150 dogs. PROCEDURE: Canine blood samples submitted to the North Carolina State University Vector-Borne Disease Diagnostic Laboratory between May 2000 and October 2003 for which results of a Babesia-specific polymerase chain reaction assay were positive were identified, and breed and geographic origin of dogs from which samples were obtained were recorded. History and hematologic abnormalities for dogs that were not APBTs were recorded, and possible associations with a recent dog bite were examined. RESULTS: Dogs positive for Babesia DNA were located in 29 states and 1 Canadian province (Ontario). Babesia gibsoni was the most commonly detected species, with B gibsoni DNA detected in blood samples from 131 of 144 (91%) dogs. Of the 131 dogs positive for B gibsoni DNA, 122 (93%) were APBTs. Of the 10 dogs positive for Babesia canis vogeli DNA, 6 were Greyhounds. In dogs other than APBTs, there was an association between having recently been bitten by another dog, particularly an APBT, and infection with B gibsoni. CONCLUSIONS AND CLINICAL RELEVANCE: Results document an expansion of the known geographic range for babesiosis among dogs in the United States. Testing for babesiosis should be pursued in dogs with clinicopathologic abnormalities consistent with immune-mediated hemolytic anemia or thrombocytopenia, particularly if there is a history of a recent dog bite.

Animals↗

PubMed1991

Geographic distribution of xanthine oxidase, free radical scavengers, creatine kinase, and lactate dehydrogenase enzyme systems in rat heart and skeletal muscle.

The geographic distribution of the following enzyme systems is described in the rat heart (left and right ventricles) and in different skeletal muscles (soleus, plantaris, and red and white gastrocnemius): xanthine oxidase and dehydrogenase, creatine kinase isoenzymes, lactate dehydrogenase isoenzymes, and the free radical scavenger enzymes superoxide dismutase, glutathione reductase, and glutathione peroxidase. No substantial difference in enzyme activities was observed between the left and right ventricles. Skeletal muscles showed a clear distinction between enzyme activities depending on their composition of oxidative fibers and glycolytic fibers.

Animals↗

PubMed2001

Assessing the association between the geographic distribution of deer ticks and seropositivity rates to various tick-transmitted disease organisms in dogs.

OBJECTIVE: To determine whether the geographic distribution of deer ticks (Ixodes scapularis) was associated with the distribution of dogs seropositive for various tick-transmitted disease organisms (ie, Borrelia burgdorferi, Rickettsia rickettsii, the human granulocytic ehrlichiosis [HGE] agent, Ehrlichia canis, and Bartonella vinsonii subsp berkhoffii). DESIGN: Serologic survey. SAMPLE POPULATION: Serum samples from 277 dogs in animal shelters and veterinary hospitals in Rhode Island. RESULTS: Overall, 143 (52%) dogs were seropositive for B burgdorferi, 59 (21.3%) were seropositive for R rickettsii, 40 (14.4%) were seropositive for the HGE agent, 8 (2.9%) were seropositive for E canis, and 6 (2.2%) were seropositive for B vinsonii. Regression analysis indicated that the natural logarithm of nymphal deer tick abundance was correlated with rate of seropositivity to the HGE agent and to B burgdorferi but not to rate of seropositivity to R rickettsii, E canis, or B vinsonii. Percentages of samples seropositive for B burgdorferi, R rickettsii, the HGE agent, and E canis were significantly higher for samples from the southwestern part of the state where ticks in general and deer ticks in particular are abundant than for samples from the northern and eastern portions of the state, where ticks are relatively rare. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that all 5 disease agents are in Rhode Island and pose a risk to dogs and humans. Knowledge concerning tick distributions may be useful in predicting the pattern of disease associated with particular tick species and may aid diagnostic, prevention, and control efforts.

Animals↗

PubMed1996

Geographic Distribution of Cytoplasmic Polyhedrosis Virus Infection in Douglas-Fir Tussock Moth Larvae, Orgyia pseudotsugata, in British Columbia

We have examined the geographic distribution and prevalence of insect-specific viral infections in Douglas-fir tussock moth populations in British Columbia. Nucleic acids extracted from field collected egg masses from 10 different locations in British Columbia were subjected to agarose gel electrophoresis and Southern blot analysis. Electrophoresis of nucleic acids after digestion with RNase A at high and low ionic strengths showed that the extra bands detected in agarose gels were double-stranded RNA (dsRNA). The dsRNA banding pattern was similar to the electropherotype of cytoplasmic polyhedrosis virus type 5. CPV infections were found in 27 of 170 DFTM larvae reared from field collected egg masses from four of 10 sites examined in three geographic regions of British Columbia. The CPV-infection rate for the DFTM larvae ranged from 10 to 86% depending on the location of the site.

Journal Article↗

PubMed1993

Geographic distribution of stroke mortality in the United States: 1939-1941 to 1979-1981.

I used data from the National Center for Health Statistics to map the geographic distribution of age-adjusted, race- and gender-specific stroke mortality rates in the United States from 1939-1941 to 1979-1981. Over this interval, stroke mortality rates declined dramatically with convergence of age-adjusted, state-specific stroke rates both within and between the various race-gender groups. For each race-gender group, high age-adjusted stroke mortality rates were significantly clustered in the southeastern United States, particularly in the South Atlantic census division, with persistent extreme rates in Georgia and the Carolinas. For whites, low-rate states were concentrated in the Mountain census division and along the northern Atlantic coast. The nonrandom distribution of stroke mortality across the United States, the large magnitude of the difference between high- and low-rate areas, the persistence of the pattern over more than four decades, the similarity of the distribution for different race-gender groups, the lack of delimitation by administrative or political boundaries, and results of national cooperative studies completed in the late 1960s and early 1970s together suggest that the pattern of excess stroke mortality is not an artifact of different diagnostic and reporting practices. Some of the observed geographic variation may be due to both the effects of selective migration and variations in the distributions of stroke risk factors.

Black or African American↗

PubMed2005

The geographic distribution of physicians revisited.

CONTEXT: While there is debate over whether the U.S. is training too many physicians, many seem to agree that physicians are geographically maldistributed, with too few in rural areas. OBJECTIVE: Official definitions of shortage areas assume the market for physician services is based on county boundaries. We wished to ascertain how the picture of a possible shortage changes using alternative measures of geographic access. We measure geographic access by the number of full-time equivalent physicians serving a community divided by the expected number of patients (possibly both from within the community and outside) receiving care from those physicians. Moreover, we wished to determine how the geographic distribution of physicians had changed since previous studies, in light of the large increase in physician numbers. DESIGN: Cross-sectional data analyses of alternative measures of geographic access to physicians in 23 states with low physician-population ratios. RESULTS: Between 1979 and 1999, the number of physicians doubled in the sample states. Although most specialties experienced greater diffusion everywhere, smaller specialties had not yet diffused to the smallest towns. Multiple measures of geographic access, including physician-to-population ratios, average distance traveled to the nearest physician, and projected average caseload per physician, confirm that residents of metropolitan areas have better geographic access to physicians. Physician-to-population ratios exhibit the largest degree of geographic disparity, but ratios in rural counties adjacent to metropolitan areas are smaller than in those not adjacent to metropolitan areas. Distance-traveled and caseload models that allow patients to cross county lines show less disparity and indicate that residents of isolated rural counties have less access than those living in counties adjacent to metropolitan areas. CONCLUSION: Geographic access to physicians has continued to improve over the past two decades, although some smaller specialties have not diffused to the most rural areas. While substantial variation in the supply of physicians across communities remains, current measures of geographic access to physicians overstate the extent of maldistribution and yield an incorrect ranking of areas according to geographic accessibility of physicians.

Cross-Sectional Studies↗