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  • One Health: Children, Waterfowl, and Lead Exposure in Northwestern Nigeria.

    Posted 2018-06-24 10:01:05 by: Mahammad A. Tafida

    Related Articles One Health: Children, Waterfowl, and Lead Exposure in Northwestern Nigeria. J Am Osteopath Assoc. 2017 Jun 01;117(6):370-376 Authors: Edwards JR, Fossum TW, Nichols KJ, Noah DL, Tarpley RJ, Prozialeck WC Abstract The One Health concept focuses on the interrelationship between the health of humans, animals, and the environment. There is a delicate balance among these relationships, and when an imbalance exists, the effects can be catastrophic. Such an imbalance occurred in 2010, when elevated lead exposure in rural communities in northwestern Nigeria resulted in the deaths of an estimated 400 children younger than 5 years in a 12-month period. Before the children became ill, waterfowl began to die in great numbers, a connection that would not be realized until much later. This review covers toxicodynamics and the neurotoxic effects of lead in the developing central nervous system, the role that animals can play in recognizing lead exposure and contamination, and environmental sources of lead exposure. The experiences in Nigeria may be especially pertinent to the emerging problems associated with lead exposure and poisoning in the United States. PMID: 28556859 [PubMed - indexed for ...

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  • The human-snail transmission environment shapes long term schistosomiasis control outcomes: Implications for improving the accuracy of predictive modeling.

    Posted 2018-06-24 10:01:05 by: Mahammad A. Tafida

    Related Articles The human-snail transmission environment shapes long term schistosomiasis control outcomes: Implications for improving the accuracy of predictive modeling. PLoS Negl Trop Dis. 2018 05;12(5):e0006514 Authors: Gurarie D, Lo NC, Ndeffo-Mbah ML, Durham DP, King CH Abstract INTRODUCTION: Schistosomiasis is a chronic parasitic trematode disease that affects over 240 million people worldwide. The Schistosoma lifecycle is complex, involving transmission via specific intermediate-host freshwater snails. Predictive mathematical models of Schistosoma transmission have often chosen to simplify or ignore the details of environmental human-snail interaction in their analyses. Schistosome transmission models now aim to provide better precision for policy planning of elimination of transmission. This heightens the importance of including the environmental complexity of vector-pathogen interaction in order to make more accurate projections. METHODOLOGY AND PRINCIPAL FINDINGS: We propose a nonlinear snail force of infection (FOI) that takes into account an intermediate larval stage (miracidium) and snail biology. We focused, in particular, on the effects of snail force of infection (FOI) on the impact of mass drug administration (MDA) in human communities. The proposed (modified) model was compared to a conventional model in terms of their predictions. A longitudinal dataset generated in Kenya field studies was used for model calibration and validation. For each sample community, we calibrated modified and conventional model systems, then used them to model outcomes for a range of MDA regimens. In most cases, the modified model predicted more vigorous post-MDA rebound, with faster relapse to baseline levels of infection. The effect was pronounced in higher risk communities. When compared to observed data, only the modified system was able to successfully predict persistent rebound of Schistosoma ...

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  • Prediction of the potential global distribution for Biomphalaria straminea, an intermediate host for Schistosoma mansoni.

    Posted 2018-06-24 10:01:05 by: Mahammad A. Tafida

    Related Articles Prediction of the potential global distribution for Biomphalaria straminea, an intermediate host for Schistosoma mansoni. PLoS Negl Trop Dis. 2018 05;12(5):e0006548 Authors: Yang Y, Cheng W, Wu X, Huang S, Deng Z, Zeng X, Yuan D, Yang Y, Wu Z, Chen Y, Zhou Y, Jiang Q Abstract BACKGROUND: Schistosomiasis is a snail-borne parasitic disease and is endemic in many tropical and subtropical countries. Biomphalaria straminea, an intermediate host for Schistosoma mansoni, is native to the southeastern part of South America and has established in other regions of South America, Central America and southern China during the last decades. S. mansoni is endemic in Africa, the Middle East, South America and the Caribbean. Knowledge of the potential global distribution of this snail is essential for risk assessment, monitoring, disease prevention and control. METHODS AND FINDINGS: A comprehensive database of cross-continental occurrence for B. straminea was compiled to construct ecological models. We used several approaches to investigate the distribution of B. straminea, including direct comparison of climatic conditions, principal component analysis and niche overlap analyses to detect niche shifts. We also investigated the impacts of bioclimatic and human factors, and then used the bioclimatic and footprint layers to predict the potential distribution of B. straminea at global scale. We detected niche shifts accompanying the invasions of B. straminea in the Americas and China. The introduced populations had enlarged its habitats to subtropical regions where annual mean temperature is relatively low. Annual mean temperature, isothermality and temperature seasonality were identified as most important climatic features for the occurrence of B. straminea. Additionally, human factors improved the model prediction (P<0.001). Our model showed that under current climate conditions the snail should ...

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  • Varicella Coinfection in Patients with Active Monkeypox in the Democratic Republic of the Congo.

    Posted 2018-06-21 10:01:19 by: Mahammad A. Tafida

    Related Articles Varicella Coinfection in Patients with Active Monkeypox in the Democratic Republic of the Congo. Ecohealth. 2017 09;14(3):564-574 Authors: Hoff NA, Morier DS, Kisalu NK, Johnston SC, Doshi RH, Hensley LE, Okitolonda-Wemakoy E, Muyembe-Tamfum JJ, Lloyd-Smith JO, Rimoin AW Abstract From 2006 to 2007, an active surveillance program for human monkeypox (MPX) in the Democratic Republic of the Congo identified 151 cases of coinfection with monkeypox virus and varicella zoster virus from 1158 suspected cases of human MPX (13%). Using clinical and socio-demographic data collected with standardized instruments by trained, local nurse supervisors, we examined a variety of hypotheses to explain the unexpectedly high proportion of coinfections among the sample, including the hypothesis that the two viruses occur independently. The probabilities of disease incidence and selection necessary to yield the observed sample proportion of coinfections under an assumption of independence are plausible given what is known and assumed about human MPX incidence. Cases of human MPX are expected to be underreported, and more coinfections are expected with improved surveillance. PMID: 28894977 [PubMed - indexed for ...

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  • Merozoite Surface Protein 1 from Plasmodium falciparum Is a Major Target of Opsonizing Antibodies in Individuals with Acquired Immunity against Malaria.

    Posted 2018-06-21 10:01:19 by: Mahammad A. Tafida

    Related Articles Merozoite Surface Protein 1 from Plasmodium falciparum Is a Major Target of Opsonizing Antibodies in Individuals with Acquired Immunity against Malaria. Clin Vaccine Immunol. 2017 Nov;24(11): Authors: Jäschke A, Coulibaly B, Remarque EJ, Bujard H, Epp C Abstract Naturally acquired immunity against malaria is largely mediated by serum antibodies controlling levels of blood-stage parasites. A limited understanding of the antigenic targets and functional mechanisms of protective antibodies has hampered the development of efficient malaria vaccines. Besides directly inhibiting the growth of Plasmodium parasites, antibodies can opsonize merozoites and recruit immune effector cells such as monocytes and neutrophils. Antibodies against the vaccine candidate merozoite surface protein 1 (MSP-1) are acquired during natural infections and have been associated with protection against malaria in several epidemiological studies. Here we analyzed serum antibodies from semi-immune individuals from Burkina Faso for their potential (i) to directly inhibit the growth of P. falciparum blood stages in vitro and (ii) to opsonize merozoites and to induce the antibody-dependent respiratory burst (ADRB) activity of neutrophils. While a few sera that directly inhibited the growth of P. falciparum blood stages were identified, immunoglobulin G (IgG) from all individuals clearly mediated the activation of neutrophils. The level of neutrophil activation correlated with levels of antibodies to MSP-1, and affinity-purified MSP-1-specific antibodies elicited ADRB activity. Furthermore, immunization of nonhuman primates with recombinant full-size MSP-1 induced antibodies that efficiently opsonized P. falciparum merozoites. Reversing the function by preincubation with recombinant antigens allowed us to quantify the contribution of MSP-1 to the antiparasitic effect of serum antibodies. Our data suggest that MSP-1, especially the ...

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  • Human Exposure to Wild Animals in the Sankuru Province of the Democratic Republic of the Congo.

    Posted 2018-06-21 10:01:19 by: Mahammad A. Tafida

    Related Articles Human Exposure to Wild Animals in the Sankuru Province of the Democratic Republic of the Congo. Ecohealth. 2017 09;14(3):552-563 Authors: Rimoin AW, Alfonso VH, Hoff NA, Doshi RH, Mulembakani P, Kisalu NK, Muyembe JJ, Okitolonda EW, Wright LL Abstract Due to the high level of biological diversity in the Congo Basin and human population dependence on bushmeat, the DRC represents an ideal location for expanding knowledge on wild animal exposures and thus the potential for transmission of zoonotic pathogens. However, limited information exists on patterns and extent of contact with wildlife in such communities. Using a cross-sectional study, 14 villages in the Sankuru Province of the DRC were surveyed between August and September 2007. Villagers ≥ 1 year of age and at home of the time of the survey were eligible and enrolled to describe and assess factors associated with animal exposures (both activity and type of animal). Among respondents, 91% reported exposure to rodents, 89% to duikers, 78% to non-human primates (NHPs), and 32% reported contact with bats in the month prior to the survey. The most frequently reported activities included eating (95%), cooking (70%), and butchering or skinning of animals (55%). The activities and animals to which subjects had contact varied by sex and age. Moreover, we observed a high correlation of the same activities across animal types. In this and other populations that rely on bushmeat, there is a high frequency of exposure to multiple animal species through various modalities. In the event of future zoonotic disease outbreaks, effective public health interventions and campaigns that mitigate the risk of animal contact during outbreaks need to be broad to include various modes of contact and should be directed to both men and women across all age groups. As available information is limited, further studies are necessary to better understand the complex ...

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  • Chemical capture of impala (Aepyceros melampus): A review of factors contributing to morbidity and mortality.

    Posted 2018-06-21 10:01:19 by: Mahammad A. Tafida

    Related Articles Chemical capture of impala (Aepyceros melampus): A review of factors contributing to morbidity and mortality. Vet Anaesth Analg. 2017 Sep;44(5):991-1006 Authors: Zeiler GE, Meyer LCR Abstract OBJECTIVE: To review the factors that contribute to morbidity and mortality of impala undergoing chemical capture, and discuss how they are potentially mitigated. DATABASES USED: PubMed, Science Direct, Google Scholar and Onderstepoort Veterinary Academic Hospital records. CONCLUSIONS AND CLINICAL RELEVANCE: Impala are an important species of antelope in Africa and are often captured during management procedures, veterinary interventions and research projects. Chemical capture is a preferred technique over physical capture and restraint for veterinary interventions as it allows for easier handling and better clinical assessment and treatment. However, this capture technique results in high mortality (4%) and morbidity rates (23%), which translates into animal welfare and economic concerns. Investigation of environmental, drug and drug delivery, and animal factors to elucidate the origin of these high rates was reviewed. The greatest risks emanate from the drug and drug delivery factors where potent opioids (etorphine and thiafentanil) cause profound respiratory compromise, that if left untreated often translates into fatalities. Furthermore, the procedure of darting, an essential tool in game capture, can cause irreparable fractures and other fatal injuries mainly through accidental misplacement of the dart into a long bone, thoracic or peritoneal cavity. Impala are anxious and flighty, and this demeanour (animal related factor) can contribute towards mortality and morbidity rates. Impala that mount an inappropriate stress response to capture tend to die; therefore, procedures that induce an intense stress response (awake clinical examinations) should be avoided. Sequela of a heightened ...

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