PubMed HealthSearch

SEARCH · PubMed Health

Results for “Disease Reservoirs”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Problems of rodent control in rural tropical areas.

Rodent control strategies, techniques, and research needs in rural tropical environments are reviewed and discussed with special reference to Mastomys natalensis, the possible reservoir of Lassa fever in West Africa.Public health rodent problems are far more serious and widespread in rural tropical areas than in developed countries. In the latter, only the commensal rodents constitute a major problem, whereas in rural tropical areas, native semidomestic species also serve as disease reservoirs and sources of infection to man. The success of rodent control programmes in developed countries depends in large part on the willingness and ability of people and governments to spend relatively large sums on research and control, on an acquired intolerance of people to rats and disease, and on a substantial economic base. These prerequisites are not usually to be found in rural tropical areas. Consequently, the rodent control techniques and programme organizations of developed countries are not directly applicable to such areas, even though the principles are the same. For this reason, it is suggested that a well-funded, integrated research and control programme should be undertaken in a known Lassa fever area, stressing public education, personnel training, and environmental management as well as rodenticidal approaches.

Africa, Western

Bat-associated histoplasmosis in Maryland bridge workers.

An epidemic of acute prolonged febrile respiratory disease affecting nine of 19 workers on a Maryland State bridge maintenance crew was diagnosed as histoplasmosis by serologic testing in all and by isolation of the organism in one. In our investigation, it was revealed that work on a particular bridge was associated with disease. Culture of bat guano from the site two months later revealed H. capsulatum. Four previously uninfected epidemiologic investigators also became ill with histoplasmosis following collection of soil and bat guano. This outbreak reveals that bats and bat guano are a source of histoplasmosis, suggests that only brief exposure is necessary for acute infection and reemphasizes that histoplasmosis is not confined to the midwestern states.

Animals

The influence of stream geology on the distribution of the bilharzia host snails, Biomphalaria pfeifferi and Bulinus (physopsis) sp.

The Gladdespruit and Komati River surveys have shown that similar environmental conditions have developed where the watercourses flowed over particular rock types. In these watercourses a potentially useful association was found between the occurrence of permanent, lentic habitats produced by the weathering of bedrock with a hardness above 5 in Mohs' Scale of Hardness and the longitudinal distribution of persistent populations of the bilharzia intermediate host snails Biomphalaria pfeifferi and Bulinus (Physopsis) sp. Bilharzia transmission follows this pattern in these waterways. Weathering of bedrock with hardness below 5 in Mohs' scale, and/or flow over beds of alluvial sand, produced perpetually lotic (flowing) environments without persistent host snail populations because of the snail's inability to tolerate high current speeds. However a few temporary populations survived in temporarily lentic habitats during the dry winter season.

Africa

Mycobacterium ulcerans in Australia.

The epidemiology of 39 case reports of infection with Mycobacterium ulcerans published during the past 25 years in Australia is presented. A review is made of the laboratory findings of the strains found in Australia and of the contribution of Australian workers to the description, treatment and prevention of this disfiguring disease.

Adolescent

Horizontal transmission of feline leukemia virus in cats.

Traditionally, cancer has not been considered an infectious disease although some multiple cases of leukemia in man and cattle have been reported. The discovery that feline lymphosarcoma was associated with an RNA virus (feline leukemia virus(FeLV)) meant that infectious transmission of the disease was a possibility. The critical question was whether the predominant method of transmission from one animal to another was 'vertical' (via the gametes) or 'horizontal' (via contagion or infection). A number of epidemiological studies have shown that the chances of healthy cats contracting lymphosarcoma are greatly increased when a cat with the disease lives in close proximity. It does not matter whether the healthy cats are related to the sick animal or not. It has also been established that viremic normal cats have an approximately 900 times greater chance of developing leukemia than cats whose FeLV status is unknown. Infectious FeLV is present in the excretions and blood of viremic animals. In the natural environment, feline lymphosarcoma occurs in clusters. The results in pet cats have been supported by experiments with cat colonies under controlled conditions and prove that horizontal transmission of FeLV occurs. This does not mean that epigenetic (infection in utero or via the milk) or vertical transmission cannot also occur. It should be possible to break the cycle of horizontal transmission of the virus by vaccination and thus control FeLV-related diseases.

Animals