Infestation

About: Infestation is a research topic. Over the lifetime, 8308 publications have been published within this topic receiving 82305 citations.

Some effects of sarcoptic mange on dogs

Abstract: Sequential changes in pathology were examined for scabies-infested dogs to determine the effects of infestation with Sarcoptes scabiei var. canis. During 8 wk of infestation with S. scabiei, the progression of the disease was evaluated weekly by skin scrape, clinical examination, and blood analyses. At 8 wk, selected organs were microscopically examined for histopathology. All infested dogs developed an advanced level of scabies infestation by 8 wk. Of the 36 blood parameters evaluated, only values for erythrocyte sedimentation rate (ESR) deviated significantly from the normal ranges for dogs. However, infested dogs had significantly (P < 0.01) lower average hemoglobin and hematocrit concentrations after 8 wk of infestation compared to their values prior to infestation or to the values for the control dogs. Red blood cell levels for infested dogs dropped significantly (P < 0.01) from preinfestation concentrations by week 8. Conversely, by 8 wk total white blood cell and neutrophil concentrations were significantly (P < 0.01) greater than uninfested controls. Also, whereas average eosinophil concentrations were not statistically different for infested dogs compared to controls, some individual infested dogs exhibited eosinophilia at 4-8 wk of infestation. The ESRs for infested dogs were significantly (P < 0.01) greater at week 6 and 8 than for experimental dogs prior to infestation or control dogs. All parameters except neutrophils had returned to preinfestation levels by 2 wk after treatment for scabies. Neutrophil concentrations were no longer significantly different by 4 wk posttreatment. There were no significant differences in serum enzyme, biochemical and electrolyte concentrations between infested and control dogs. Organ histopathology was essentially normal with none of the findings attributable to scabies infestation. Chronic infestations of scabies in mammals may cause pro- gressive deterioration of the hosts' health that is evidenced by a progressing mangy appearance (alopecia, hyperkeratosis, der- matitis), weight loss, reduced weight gain, increased food intake, and reduced milk production in cattle (Brownlie and Harrison,

Field Test of Resistance to Acarapis woodi (Acari: Tarsonemidae) and of Colony Production by Four Stocks of Honey Bees (Hymenoptera: Apidae)

Abstract: Characteristics of four stocks of honey bees, Apis mellifera L., were evaluated in colonies managed commercially for honey production at three U.S. locations―one north-central location (Iowa) and two south-central locations (Mississippi, Texas). Stocks were compared for 1 yr beginning in October 1991 to determine the levels of infestation by tracheal mites, Acarapis woodi (Rennie), and to ascertain survival rates, levels of honey production, and sizes of adult and brood populations. Test stocks were ARS-Y-C-1 ( A. mellifera carnica Pollman, imported from Yugoslavia), Buckfast (imported from the United Kingdom), Survivor (developed from colonies in a Louisiana apiary believed to have had severe tracheal mite infestation), and Unchallenged (developed from a feral Louisiana population never exposed to tracheal mites). Stocks initially were represented by 15-20 colonies at each location. After an initial inoculation of mite-infested bees in the autuinn, infestation percentages increased more markedly in the susceptible (Survivor and Unchallenged) stocks than in the resistant (ARS-Y-C-1 and Buckfast) stocks. Mean infestation percentages in the resistant stocks remained <15% and thus were below levels associated with economic damage. Mean infestation percentages in susceptible stocks ranged from 13 to 95% at each site during the final 6 mo of the study Numbers of mites per infested bee differed between stocks in 4 of 21 samples; mite numbers tended to be greatest in Survivor bees and least in Buckfast bees. Mortality increased more rapidly among susceptible colonies than among resistant colonies as infestation increased in 1992. Honey production was greatest by Buckfast, intermediate by Survivor, and least by Unchallenged and ARS-Y-C-l colonies. Differences in population sizes of adult bees and brood occurred in approximately half of samples taken in spring and autumn; Survivor and Buckfast colonies were most populous. Stock characteristics showed no interaction of genotype with environment, i.e., location. Our results support the feasibility of an approach using genetically regulated resistance to manage problems caused by tracheal mites.

Prevalence of head lice infestation and pediculicidal effect of permethrine shampoo in primary school girls in a low-income area in southeast of Iran

Abstract: Head lice infestation is a common public health problem that is most prevalent in primary school children throughout the world, especially in developing countries including different parts of Iran. This study aimed to determine the prevalence and risk factors associated with head lice infestation and pediculicidal effect of 1% permethrin shampoo in primary schools girls of Bashagard County, one of the low socioeconomic areas in southeast of Iran. In this interventional study six villages with similar demographical situations were selected and randomly assigned into intervention and control areas. In each area 150 girl students aged 7–12 years were selected randomly and screened for head lice infestation by visual scalp examination. In intervention area, treatment efficacy of 1% permethrin shampoo was evaluated via re-examination for infestation after one, two, and three weeks. Pre-tested structured questionnaire was used to collect data on socio-demographic and associated factors of head lice infestation. The prevalence of head lice infestation was 67.3%. There was significant association between head lice infestation and school grade, family size, parents’ literacy, bathing facilities, frequency of hair washing, and use of shared articles (p < 0.05). The effectiveness of 1% permethrin shampoo for head lice treatment was 29.2, 68.9, and 90.3% after the first, second, and third weeks, respectively. The head lice infestation is a health problem in primary school girls of Bashagard County. Improvement of socioeconomic status and providing appropriate educational programs about head lice risk factors and prevention can be effective for reduction of infestation in this area. This trial has been registered and approved by Hormozgan University of Medical Sciences ethical committee (Trial No.764). Trial registration date: March 17 2014.

Intensity of hookworm infestation in alabama: its relationship to residence, occupation, age, sex and race

Abstract: Hookworm infestation is one of the major public health problems of Alabama. Here the parasite has a wide distribution, for scarcely any county, town or village that has been studied has been found free of infestation. Among children of school age the incidence ranges from less than 5 per cent. in some of the larger towns to 95 per cent, in the heavily infested rural communities. Formerly, every case of hookworm infestation has been considered hookworm disease, and the public health plan of organization has been to treat every child until he is entirely free from parasites. Recent studies 1 have shown, however, that the important factor in hookworm disease control is not the incidence but the intensity of infestation from the point of view either of an individual or of a community. The great proportion of persons with hookworm infestation of slight degree suffer no measurable harm, and should