Parasitic Diseases Commons^™

Assessing The Value And Knowledge Gains From An Online Tick Identification And Tick-Borne Disease Management Course For The Southeastern United States, Catherine A. Lippi, Holly D. Gaff, Alexis L. White, Sadie J. Ryan

Biological Sciences Faculty Publications

Background

Tick-borne diseases are a growing public health threat in the United States. Despite the prevalence and rising burden of tick-borne diseases, there are major gaps in baseline knowledge and surveillance efforts for tick vectors, even among vector control districts and public health agencies. To address this issue, an online tick training course (OTTC) was developed through the Southeastern Center of Excellence in Vector-Borne Diseases (SECOEVBD) to provide a comprehensive knowledge base on ticks, tick-borne diseases, and their management.

Methods

The OTTC consisted of training modules covering topics including tick biology, tick identification, tick-borne diseases, and public health, personal tick …

Rickettsial Pathogen Perturbs Tick Circadian Gene To Infect The Vertebrate Host, Supreet Khanal, Vikas Taank, John F. Anderson, Hameeda Sultana, Girish Neelakanta

Biological Sciences Faculty Publications

Ixodes scapularis is a medically important tick that transmits several microbes to humans, including rickettsial pathogen Anaplasma phagocytophilum. In nature, these ticks encounter several abiotic factors including changes in temperature, humidity, and light. Many organisms use endogenously generated circadian pathways to encounter abiotic factors. In this study, we provide evidence for the first time to show that A. phagocytophilum modulates the arthropod circadian gene for its transmission to the vertebrate host. We noted a circadian oscillation in the expression of arthropod clock, bmal1, period and timeless genes when ticks or tick cells were exposed to alternate 12 h …

Can Repurposing Drugs Play A Role In Malaria Control?, Roland A. Cooper, Laura Kirkman

Natural Sciences and Mathematics | Faculty Scholarship

Innovative drug treatments for malaria, optimally with novel targets, are needed to combat the threat of parasite drug resistance. As drug development efforts continue, there may be a role for a host-targeting, repurposed cancer drug administered together with an artemisinin combination therapy that was shown to improve the speed of recovery from a malaria infection.

Associations Between Varied Susceptibilities To Pfatp4 Inhibitors And Genotypes In Ugandan Plasmodium Falciparum Isolates., Oriana Kreutzfeld, Stephanie A. Rasmussen, Aarti A. Ramanathan, Patrick K. Tumwebaze, Oswald Byaruhanga, Thomas Katairo, Victor Asua, Martin Okitwi, Stephen Orena, Jennifer Legac, Melissa D. Conrad, Samuel L. Nsobya, Ozkan Aydemir, Jeffrey Bailey, Maelle Duffey, Brett R. Bayles, Akhil B. Vaidya, Roland A. Cooper, Philip J. Rosenthal

Natural Sciences and Mathematics | Faculty Scholarship

Among novel compounds under recent investigation as potential new antimalarial drugs are three independently developed inhibitors of the Plasmodium falciparum P-type ATPase (PfATP4): KAE609 (cipargamin), PA92, and SJ733. We assessed ex vivo susceptibilities to these compounds of 374 fresh P. falciparum isolates collected in Tororo and Busia districts, Uganda, from 2016 to 2019. Median IC50s were 65 nM for SJ733, 9.1 nM for PA92, and 0.5 nM for KAE609. Sequencing of pfatp4 for 218 of these isolates demonstrated many nonsynonymous single nucleotide polymorphisms; the most frequent mutations were G1128R (69% of isolates mixed or mutant), Q1081K/R (68%), G223S (25%), N1045K …

Drug Susceptibility Of Plasmodium Falciparum In Eastern Uganda: A Longitudinal Phenotypic And Genotypic Study, Patrick K. Tumwebaze, Thomas Katairo, Martin Okitwi, Oswald Byaruhanga, Stephen Orena, Victor Asua, Marvin Duvalsaint, Jennifer Legac, Sevil Chelebieva, Frida G. Ceja, Stephanie A. Rasmussen, Melissa D. Conrad, Samuel L. Nsobya, Ozkan Aydemir, Jeffrey A. Bailey, Brett R. Bayles, Philip J. Rosenthal, Roland A. Cooper

Natural Sciences and Mathematics | Faculty Scholarship

Background: Treatment and control of malaria depends on artemisinin-based combination therapies (ACTs) and is challenged by drug resistance, but thus far resistance to artemisinins and partner drugs has primarily occurred in southeast Asia. The aim of this study was to characterise antimalarial drug susceptibility of Plasmodium falciparum isolates from Tororo and Busia districts in Uganda.

Methods: In this prospective longitudinal study, P falciparum isolates were collected from patients aged 6 months or older presenting at the Tororo District Hospital (Tororo district, a site with relatively low malaria incidence) or Masafu General Hospital (Busia district, a high-incidence site) in eastern Uganda …

An Inactivated Bacterium (Paraprobiotic) Expressing Bacillus Thuringiensis Cry5b As A Therapeutic For Ascaris And Parascaris Spp. Infections In Large Animals, Joseph F. Urban, Martin K. Nielsen, David Gazzola, Yue Xie, Ethiopia Beshah, Yan Hu, Hanchen Li, Florentina Rus, Kelly Flanagan, Austin Draper, Sridhar Vakalapudi, Robert W. Li, Gary R. Ostroff, Raffi V. Aroian

Maxwell H. Gluck Equine Research Center Faculty Publications

Ascaris and Parascaris are important parasites in the family Ascarididae, large, ubiquitous intestinal-dwelling nematodes infecting all classes of vertebrates. Parasitic nematode drug resistance in veterinary medicine and drug recalcitrance in human medicine are increasing worldwide, with few if any new therapeutic classes on the horizon. Some of these parasites are zoonotic, e.g., Ascaris is passed from humans to pigs and vice versa. The development of new therapies against this family of parasites would have major implications for both human and livestock health. Here we tested the therapeutic ability of a paraprobiotic or dead probiotic that expresses the Bacillus …

Serological Proteomic Screening And Evaluation Of A Recombinant Egg Antigen For The Diagnosis Of Low-Intensity Schistosoma Mansoni Infections In Endemic Area In Brazil, Vanessa Silva-Moraes, Lisa Marie Shollenberger, William Castro-Borges, Ana Lucia Teles Rabello, Donald A. Harn, Lia Carolina Soares Medeiros, Wander De Jesus Jeremias, Liliane Maria Vidal Siqueira, Caroline Stephane Salviano Pereira, Maria Luysa Camargos Pedrosa, Nathalie Bonatti Franco Almeida, Aureo Almeida, Jose Roberto Lambertucci, Nidia Francisca De Figueiredo Carneiro, Paulo Marcos Zech Coelho, Refaella Fortini Queiroz Grenfell

Biological Sciences Faculty Publications

Background

Despite decades of use of control programs, schistosomiasis remains a global public health problem. To further reduce prevalence and intensity of infection, or to achieve the goal of elimination in low-endemic areas, there needs to be better diagnostic tools to detect low-intensity infections in low-endemic areas in Brazil. The rationale for development of new diagnostic tools is that the current standard test Kato-Katz (KK) is not sensitive enough to detect low-intensity infections in low-endemic areas. In order to develop new diagnostic tools, we employed a proteomics approach to identify biomarkers associated with schistosome-specific immune responses in hopes of developing …

Antimalarial Proteasome Inhibitor Reveals Collateral Sensitivity From Intersubunit Interactions And Fitness Cost Of Resistance., Laura A. Kirkman, Wenhu Zhan, Joseph Visone, Alexis Dziedziech, Pradeep K. Singh, Hao Fan, Xinran Tong, Igor Bruzual, Ryoma Hara, Masanori Kawasaki, Toshihiro Imaeda, Rei Okamoto, Kenjiro Sato, Mayako Michino, Elena Fernandez Alvaro, Liselle F. Guiang, Laura M. Sanz, Daniel J. Mota, Kavitha Govindasamy, Rong Wang, Yan Ling, Patrick K. Tumwebaze, George Sukenick, Lei Shi, Jeremie Vendome, Purnima Bhanot, Philip J. Rosenthal, Kazuyoshi Aso, Michael A. Foley, Roland A. Cooper, Bjorn Kafsack, J Stone Doggett, Carl F. Nathan, Gang Lin

Natural Sciences and Mathematics | Faculty Scholarship

We describe noncovalent, reversible asparagine ethylenediamine (AsnEDA) inhibitors of the Plasmodium falciparum proteasome (Pf20S) β5 subunit that spare all active subunits of human constitutive and immuno-proteasomes. The compounds are active against erythrocytic, sexual, and liver-stage parasites, against parasites resistant to current antimalarials, and against P. falciparum strains from patients in Africa. The β5 inhibitors synergize with a β2 inhibitor in vitro and in mice and with artemisinin. P. falciparum selected for resistance to an AsnEDA β5 inhibitor surprisingly harbored a point mutation in the noncatalytic β6 subunit. The β6 mutant was resistant to the species-selective Pf20S β5 inhibitor but remained …

Private Sector Role, Readiness And Performance For Malaria Case Management In Uganda, 2015., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Henry Kaula, Peter Buyungo, Jimmy Opigo

Collected Faculty Scholarship

BACKGROUND: Several interventions have been put in place to promote access to quality malaria case management services in Uganda's private sector, where most people seek treatment. This paper describes evidence using a mixed-method approach to examine the role, readiness and performance of private providers at a national level in Uganda. These data will be useful to inform strategies and policies for improving malaria case management in the private sector.

METHODS: The ACTwatch national anti-malarial outlet survey was conducted concurrently with a fever case management study. The ACTwatch nationally representative anti-malarial outlet survey was conducted in Uganda between May 18th 2015 …

Simulating Within-Vector Generation Of The Malaria Parasite Diversity, Lauren M. Childs, Olivia F. Prosper

Mathematics Faculty Publications

Plasmodium falciparum, the most virulent human malaria parasite, undergoes asexual reproduction within the human host, but reproduces sexually within its vector host, the Anopheles mosquito. Consequently, the mosquito stage of the parasite life cycle provides an opportunity to create genetically novel parasites in multiply-infected mosquitoes, potentially increasing parasite population diversity. Despite the important implications for disease transmission and malaria control, a quantitative mapping of how parasite diversity entering a mosquito relates to diversity of the parasite exiting, has not been undertaken. To examine the role that vector biology plays in modulating parasite diversity, we develop a two-part model framework …

Testing Times: Trends In Availability, Price, And Market Share Of Malaria Diagnostics In The Public And Private Healthcare Sector Across Eight Sub-Saharan African Countries From 2009 To 2015., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Kara Hanson, Catherine Goodman

Collected Faculty Scholarship

BACKGROUND: The World Health Organization guidelines have recommended that all cases of suspected malaria should receive a confirmatory test with microscopy or a malaria rapid diagnostic test (RDT), however evidence from sub-Saharan Africa (SSA) illustrates that only one-third of children under five with a recent fever received a test. The aim of this study was to evaluate availability, price and market share of microscopy and RDT from 2009/11 to 2014/15 in 8 SSA countries, to better understand barriers to improving access to malaria confirmatory testing in the public and private health sectors.

RESULTS: Repeated national cross-sectional quantitative surveys were conducted …

Private Sector Opportunities And Threats To Achieving Malaria Elimination In The Greater Mekong Subregion: Results From Malaria Outlet Surveys In Cambodia, The Lao Pdr, Myanmar, And Thailand., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Sochea Phok, Saysana Phanalasy, Si Thu Thein, Asawin Likhitsup

Collected Faculty Scholarship

BACKGROUND: The aim of this paper is to review multi-country evidence of private sector adherence to national regulations, guidelines, and quality-assurance standards for malaria case management and to document current coverage of private sector engagement and support through ACTwatch outlet surveys implemented in 2015 and 2016.

RESULTS: Over 76,168 outlets were screened, and approximately 6500 interviews were conducted (Cambodia, N = 1303; the Lao People's Democratic Republic (PDR), N = 724; Myanmar, N = 4395; and Thailand, N = 74). There was diversity in the types of private sector outlets providing malaria treatment across countries, and the extent to which …

The Malaria Testing And Treatment Landscape In Benin., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Cyprien Zinsou, Adjibabi Bello Cherifath

Collected Faculty Scholarship

BACKGROUND: Since 2004, artemisinin-based combination therapy (ACT) has been the first-line treatment for uncomplicated malaria in Benin. In 2016, a medicine outlet survey was implemented to investigate the availability, price, and market share of anti-malarial treatment and malaria diagnostics. Results provide a timely and important benchmark to measure future interventions aimed at increasing access to quality malaria case management services.

METHODS: Between July 5th to August 6th 2016, a cross sectional, nationally-representative malaria outlet survey was conducted in Benin. A census of all public and private outlets with potential to distribute malaria testing and/or treatment was implemented among 30 clusters …

Anti-Malarial Landscape In Myanmar: Results From A Nationally Representative Survey Among Community Health Workers And The Private Sector Outlets In 2015/2016., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Si Thu Thein, Hnin Su Su Khin, Aung Thi

Collected Faculty Scholarship

BACKGROUND: In 2015/2016, an ACTwatch outlet survey was implemented to assess the anti-malarial and malaria testing landscape in Myanmar across four domains (Eastern, Central, Coastal, Western regions). Indicators provide an important benchmark to guide Myanmar's new National Strategic Plan to eliminate malaria by 2030.

METHODS: This was a cross-sectional survey, which employed stratified cluster-random sampling across four regions in Myanmar. A census of community health workers (CHWs) and private outlets with potential to distribute malaria testing and/or treatment was conducted. An audit was completed for all anti-malarials, malaria rapid diagnostic tests.

RESULTS: A total of 28,664 outlets were approached and …

Insights Into The Availability And Distribution Of Oral Artemisinin Monotherapy In Myanmar: Evidence From A Nationally Representative Outlet Survey., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Si Thu Thein, Hnin Su Su Khin, Aung Thi

Collected Faculty Scholarship

BACKGROUND: The containment of artemisinin resistance in Myanmar, historically an important probable origin and route of anti-malarial resistance to the India sub-continent and beyond, is crucial to global malaria control and elimination. This paper describes what is currently known about the sale and distribution of oral artemisinin monotherapy (AMT) across Myanmar, where this medicine is commonly found.

METHODS: A nationally representative 2015 outlet survey was conducted in the private sector, and among community health workers across four geographical domains. A national sample of outlets was screened for availability of malaria testing and treatment, and an audit was completed for all …

Evidence On Anti-Malarial And Diagnostic Markets In Cambodia To Guide Malaria Elimination Strategies And Policies, Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Sochea Phok, Dysoley Lek

Collected Faculty Scholarship

BACKGROUND: Understanding Cambodia's anti-malarial and diagnostic landscape in 2015 is critical for informing and monitoring strategies and policies as Cambodia moves forward with national efforts to eliminate malaria. The aim of this paper is to present timely and key findings on the public and private sector anti-malarial and diagnostic landscape in Cambodia. This evidence can serve as a baseline benchmark for guiding implementation of national strategies as well as other regional initiatives to address malaria elimination activities.

METHODS: From August 17th to October 1st, 2015, a cross sectional, nationally-representative malaria outlet survey was conducted in Cambodia. A census of all …

The Malaria Testing And Treatment Landscape In Mainland Tanzania, 2016., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Daniel Michael, Sigsbert Patila Mkunde

Collected Faculty Scholarship

BACKGROUND: Understanding the key characteristics of malaria testing and treatment is essential to the control of a disease that continues to pose a major risk of morbidity and mortality in mainland Tanzania, with evidence of a resurgence of the disease in recent years. The introduction of artemisinin combination therapy (ACT) as the first-line treatment for malaria, alongside policies to promote rational case management following testing, highlights the need for evidence of anti-malarial and testing markets in the country. The results of the most recent mainland Tanzania ACTwatch outlet survey are presented here, including data on the availability, market share and …

A 9-Year-Old Boy With A Chest Mass And Eosinophilia., Laura E. Norton, Sean N. Curtis, Jennifer L. Goldman

Manuscripts, Articles, Book Chapters and Other Papers

No abstract provided.

The Toxoplasma Gondii Cyst Wall Protein Cst1 Is Critical For Cyst Wall Integrity And Promotes Bradyzoite Persistence, Tadakimi Tomita, David J. Bzik, Yan Fen Ma, Barbara A. Fox

Dartmouth Scholarship

Toxoplasma gondii infects up to one third of the world's population. A key to the success of T. gondii as a parasite is its ability to persist for the life of its host as bradyzoites within tissue cysts. The glycosylated cyst wall is the key structural feature that facilitates persistence and oral transmission of this parasite. Because most of the antibodies and reagents that recognize the cyst wall recognize carbohydrates, identification of the components of the cyst wall has been technically challenging. We have identified CST1 (TGME49_064660) as a 250 kDa SRS (SAG1 related sequence) domain protein with a large …

Lack Of Il-15 Results In The Suboptimal Priming Of Cd4+ T Cell Response Against An Intracellular Parasite, Crescent L. Combe, Magali M. Moretto, Joseph D. Schwartzman, Jason P. Gigley, David J. Bzik, Imtiaz A. Khan

Dartmouth Scholarship

IFN-gamma-producing CD4+ T cells, although important for protection against acute Toxoplasma gondii infection, can cause gut pathology, which may prove to be detrimental for host survival. Here we show that mice lacking IL-15 gene develop a down-regulated IFN-gamma-producing CD4+ T cell response against the parasite, which leads to a reduction in gut necrosis and increased level of survival against infection. Moreover, transfer of immune CD4+ T cells from WT to IL-15-/- mice reversed inhibition of gut pathology and caused mortality equivalent to levels of parental WT mice. Down-regulated CD4+ T cell response in the absence of IL-15, manifested as reduced …

Ups And Downs Of Mucosal Cellular Immunity Against Protozoan Parasites, Lloyd H. Kasper, Dominique Buzoni-Gatel

Dartmouth Scholarship

No abstract provided.

Murine Gamma Interferon Fails To Inhibit Toxoplasma Gondii Growth In Murine Fibroblasts., Joseph D. Schwartzman, Steven L. Gonias, E R. Pfefferkorn

Dartmouth Scholarship

Although treatment of human macrophages or fibroblasts with human gamma interferon results in the inhibition of intracellular Toxoplasma gondii, murine gamma interferon stimulated only murine macrophages, not murine fibroblasts, to inhibit T. gondii. This species difference may be important in understanding the control of acute and chronic toxoplasmosis.