Abstracts 1190
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354 1190 < 0.001, p < 0.05). A similar increase in histamine release was seen when stimulating with ionomycin (mean % of total histamine release from QUANTITATIVE PCR-BASED ASSESSMENT OF infected children before treatment = 49.30 vs. 76.71 from children post- ANGIOSTRONGYLUS CANTONENSIS IN RATTUS RATTUS treatment, p < 0.0008). These results suggest that the ability of basophils FROM HAWAII to respond to IgE-dependent and IgE-independent activation is suppressed during intestinal helminth infection of humans. This suppression appears 1 2 2 Rebecca Bandea , Wesley Warashina , Arlene Buchholz , Sarah Y. to require the continuous presence of helminths as basophil histamine 2 1 1 Park , Yvonne Qvarnstrom , Alexandre J. da Silva releasability increases shortly after helminths are eliminated. These findings 1Centers for Disease Control and Prevention, Atlanta, GA, United States, may explain why helminth infections protect against allergic disease. 2Hawaii Department of Health, Honolulu, HI, United States Angiostrongylus cantonensis is the most common parasite causing human 1192 eosinophilic meningitis worldwide. This nematode’s infectious larvae SPATIAL PATTERNING OF HEALTH DISPARITIES AND develop in mollusks, but can also be present in paratenic hosts. The major ENVIRONMENTAL FACTORS ASSOCIATED WITH ASCARIS route of infection is thought to be accidental consumption of infected LUMBRICOIDES PREVALENCE IN BOLIVIA mollusks in fresh produce or other foods. A survey performed in 2007 on mollusks collected in Hawaii main island showed an infective rate Julie A. Clennon, Alexandra D. Huttinger, Emily R. Smith, ranging from 24 to 78% depending on the mollusk species analyzed. Christine L. Moe The severe cases of eosinophilic meningitis recently reported could be Emory University, Rollins School of Public Health, Atlanta, GA, United due to overexposure of humans to highly infected mollusks; there are States no measures in place to control the spread of A. cantonensis in Hawaii. The aim of this study was to determine the prevalence of A. cantonensis Infection with Ascaris lumbricoides, a soil-transmitted helminth (STH), in rats, the most efficient definitive hosts for this parasite. A total of affects as many as one billion people worldwide, and causes an estimated 62 rats were trapped in 4 Hawaiian communities. The presence of A. 10.5 million disability-adjusted life-years (DALYs) lost. STH prevalence data cantonensis was initially assessed by morphologic identification of adult for Bolivia is sparse. A 2009 literature review found only 7 studies in the worms in lungs and hearts of the animals. DNA was then extracted from last 25 years that offer prevalence estimates for any region of Bolivia. A 28 randomly selected lung and heart tissue samples obtained from these review conducted in 2006, that reported data from 1976-2003, showed animals. The DNA extracts were evaluated using a quantitative TaqMan that A. lumbricoides infection prevalence varies geographically across PCR validated for diagnostic detection of A. cantonensis. A total of 60 % Bolivia, from 1-28% in the Western high plains to 15-96% in the Eastern (n=37) of the rats were positive by morphology, while 100% of the tissue tropical lowlands. Although data on STH prevalence in Bolivia is patchy, samples examined with the PCR were positive. A quantitative analysis of there is information available on environmental and social risk factors the PCR results indicated that 32 % (n=9) of the rat samples contained A. known to be associated with A. lumbricoides prevalence. Environmental cantonensis DNA corresponding to more than 100 larvae in approximately conditions, particularly temperature and soil moisture, largely determine 25 mg of tissue. Together with previous studies, this data indicates that global distribution of A. lumbricoides. Social factors, such as piped water, angiostrongyliasis may be a more serious public health issue in Hawaii sanitation and improved housing (absence of dirt floors), are associated than currently estimated and that measures to control its spread in with lower STH infection. Using spatial autocorrelation statistics (Moran’s mollusks and rodents may be warranted. I and Local Indicator of Spatial Association [LISA]), we examined the spatial distribution of risk factors associated with increased prevalence 1191 of A. lumbricoides infection. Subsequently, we created a risk model integrating environmental and social factors with previous community- INCREASED BASOPHIL RESPONSIVENESS AFTER level A. lumbricoides survey data. This model is a cost-effective way to ANTHELMINTIC TREATMENT IN A COASTAL ECUADORAN predict areas of high and low STH endemicity in the absence of nationally POPULATION representative prevalence data. The model can be used to inform efforts to fill information gaps on prevalence and intensity of STH infections and 1 1 2 1 David Larson , Marc P. Hübner , Philip J. Cooper , Edward Mitre better focus mass drug administration campaigns and water, sanitation 1Uniformed Services University of the Health Sciences, Bethesda, MD, and housing infrastructure investments to mitigate STH infections across United States, 2Instituto de Microbiologia, Universidad San Francisco de Bolivia. Quito, Quito, Ecuador As basophils function as allergy effector cells and may be involved in 1193 initiating and perpetuating allergic diseases, it is possible that much of HOOKWORM AND TRICHURIS INFECTIONS ASSOCIATED the allergy-protective effect conferred by helminths is through their effect WITH ANEMIA DURING PREGNANCY on basophils. Recently, we demonstrated that basophil responsiveness decreases in murine models of chronic helminth infection. In this study, Theresa W. Gyorkos1, Nicolas L. Gilbert1, Renee Larocque2, we tested the hypothesis that basophil responsiveness is suppressed Martin Casapia3 during helminth infection of humans. Twenty-three children infected with 1McGill University, Montreal, QC, Canada, 2Global Health Research intestinal helminths were identified by parasitological examination of Initiative, Ottawa, ON, Canada, 3Asociacion Civil Selva Amazonica, Iquitos, stool samples in Esmeraldas, Ecuador. Peripheral blood cells from these Peru children were washed twice and stimulated with increasing concentrations of anti-IgE and 5 µg/ml ionomycin. Basophil activation was determined The objective of this study was to assess changes during pregnancy in by measuring histamine release into the supernatant using a competitive the association between the intensity of soil-transmitted helminth (STH) ELISA. Children were then treated with ivermectin and 2 doses of infections and hemoglobin (Hb) levels, following iron supplementation albendazole and histamine release from blood basophils measured again and mebendazole administration, in an endemic region of Peru. Data from two weeks later. A two week timepoint was chosen as basophil half-life a randomized clinical trial on the effect of mebendazole on birthweight is estimated to be between 5-8 days. Significantly more histamine was were re-analyzed. Pregnant women (N=935) recruited in their second released from basophils after anthelmintic treatment when blood was trimester provided baseline data on STH infections and anemia. All women stimulated with 0.5, 0.125, and 0.031 µg/ml anti-IgE (mean % of total were given iron supplements (60 mg/d); half were randomly allocated to histamine release from infected children before treatment = 40.38, 43.12, receive single dose 500mg mebendazole and half placebo. Hb was also 31.49 vs. 55.17, 60.53, 44.89 from children post-treatment, p < 0.01, p determined in the third trimester. Mean Hb level increased from 11.03 to 11.39 g/dL between the second and the third trimester. Hookworm www.astmh.org 355 (prevalence 46.3%) and Trichuris (76.1%) infections, but not Ascaris 1195 (63.9%), in the second trimester were independently associated with lower Hb in both the second and third trimester. Trichuris >1200 epg was MOLECULAR EPIDEMIOLOGY OF BOVINE TUBERCULOSIS also associated with a lower increase of Hb between the second and the ACROSS THE UNITED STATES-MEXICO BORDER: third trimester (ΔHb = -0.26 g/dL, p=0.026). The prevalence of anemia SUPPORTING STRATEGIES FOR ANIMAL AND PUBLIC HEALTH (Hb < 11 g/dL) decreased from 46.8% to 34.7% between the second and INTERVENTIONS the third trimesters. Hookworm and Trichuris infections were significantly and independently associated with increased risk of anemia in the third James Higgins, Tod Stuber, Patrick Camp, Doris Bravo, David trimester. The adjusted OR for hookworms >600 epg was 1.52 (95% Farrell, Beth Harris CI 1.01 to 2.28), and the adjusted OR for Trichuris >1200 epg was 1.72 NVSL, APHIS, United States Department of Agriculture, Ames, IA, United (95% CI 1.14 to 2.61). Mebendazole treatment was not associated with States Hb or with the prevalence of anemia, and did not modify the relationship Bovine tuberculosis, caused by Mycobacterium bovis, is a major global between helminths and Hb. In conclusion, in pregnancy, both hookworm cause of respiratory disease and decreased production in beef and dairy and Trichuris infections are associated with increased risk of anemia. cattle. Human infections with M. bovis represent an emerging public Infected women remain at higher risk of anemia throughout pregnancy, health concern in immigrant communities in the US. The epidemiology irrespective of mebendazole administration. These data suggest that more of zoonotic M. bovis infection is complex, but may be associated with effective deworming