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The Malaria Testing And Treatment Landscape In Kenya: Results From A Nationally Representative Survey Among The Public And Private Sector In 2016., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Anne Musuva, Waqo Ejersa, Rebecca Kiptui, Dorothy Memusi, Edward Abwao Dec 2017

The Malaria Testing And Treatment Landscape In Kenya: Results From A Nationally Representative Survey Among The Public And Private Sector In 2016., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Anne Musuva, Waqo Ejersa, Rebecca Kiptui, Dorothy Memusi, Edward Abwao

Collected Faculty and Staff Scholarship

BACKGROUND: Since 2004, Kenya's national malaria treatment guidelines have stipulated artemisinin-based combination therapy (ACT) as first-line treatment for uncomplicated malaria, and since 2014, confirmatory diagnosis of malaria in all cases before treatment has been recommended. A number of strategies to support national guidelines have been implemented in the public and private sectors in recent years. A nationally-representative malaria outlet survey, implemented across four epidemiological zones, was conducted between June and August 2016 to provide practical evidence to inform strategies and policies in Kenya towards achieving national malaria control goals.

RESULTS: A total of 17,852 outlets were screened and 2271 …


When It Just Won't Go Away: Oral Artemisinin Monotherapy In Nigeria, Threatening Lives, Threatening Progress., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Chinazo Ujuju, Jennifer Anyanti, Paul N Newton, Godwin Ntadom Dec 2017

When It Just Won't Go Away: Oral Artemisinin Monotherapy In Nigeria, Threatening Lives, Threatening Progress., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Chinazo Ujuju, Jennifer Anyanti, Paul N Newton, Godwin Ntadom

Collected Faculty and Staff Scholarship

BACKGROUND: Oral artemisinin monotherapy (AMT), an important contributor to multi-drug resistant malaria, has been banned in Nigeria. While oral AMT has scarcely been found for several years now in other malaria-endemic countries, availability has persisted in Nigeria's private sector. In 2015, the ACTwatch project conducted a nationally representative outlet survey. Results from the outlet survey show the extent to which oral AMT prevails in Nigeria's anti-malarial market, and provide key product information to guide strategies for removal.

RESULTS: Between August 10th and October 3rd, 2015 a total of 13,480 outlets were screened for availability of anti-malarials and/or malaria blood testing …


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 May 2017

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 and Staff 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 …


Do Anti-Malarials In Africa Meet Quality Standards? The Market Penetration Of Non Quality-Assured Artemisinin Combination Therapy In Eight African Countries., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Paul N Newton, Kara Hanson, Catherine Goodman May 2017

Do Anti-Malarials In Africa Meet Quality Standards? The Market Penetration Of Non Quality-Assured Artemisinin Combination Therapy In Eight African Countries., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Paul N Newton, Kara Hanson, Catherine Goodman

Collected Faculty and Staff Scholarship

BACKGROUND: Quality of artemisinin-based combination therapy (ACT) is important for ensuring malaria parasite clearance and protecting the efficacy of artemisinin-based therapies. The extent to which non quality-assured ACT (non-QAACT), or those not granted global regulatory approval, are available and used to treat malaria in endemic countries is poorly documented. This paper uses national and sub-national medicine outlet surveys conducted in eight study countries (Benin, Kinshasa and Kantanga [Democratic Republic of the Congo, DRC], Kenya, Madagascar, Nigeria, Tanzania, Uganda and Zambia) between 2009 and 2015 to describe the non-QAACT market and to document trends in availability and distribution of non-QAACT in …


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 May 2017

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 and Staff 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 …


A Variant Pfcrt Isoform Can Contribute To Plasmodium Falciparum Resistance To The First-Line Partner Drug Piperaquine, Satish K. Dhingra, Devasha Redhi, Jill M. Combrinck, Tomas Yeo, John Okombo, Philipp P. Henrich, Ann N. Cowell, Purva Gupta, Matthew L. Stegman, Jonathan M. Hoke, Roland A. Cooper, Elizabeth Winzeler, Sachel Mok, Timothy J. Egan, David A. Fidock May 2017

A Variant Pfcrt Isoform Can Contribute To Plasmodium Falciparum Resistance To The First-Line Partner Drug Piperaquine, Satish K. Dhingra, Devasha Redhi, Jill M. Combrinck, Tomas Yeo, John Okombo, Philipp P. Henrich, Ann N. Cowell, Purva Gupta, Matthew L. Stegman, Jonathan M. Hoke, Roland A. Cooper, Elizabeth Winzeler, Sachel Mok, Timothy J. Egan, David A. Fidock

Collected Faculty and Staff Scholarship

Current efforts to reduce the global burden of malaria are threatened by the rapid spread throughout Asia of Plasmodium falciparum resistance to artemisininbased combination therapies, which includes increasing rates of clinical failure with dihydroartemisinin plus piperaquine (PPQ) in Cambodia. Using zinc finger nucleasebased gene editing, we report that addition of the C101F mutation to the chloroquine (CQ) resistance-conferring PfCRT Dd2 isoform common to Asia can confer PPQ resistance to cultured parasites. Resistance was demonstrated as significantly higher PPQ concentrations causing 90% inhibition of parasite growth (IC90) or 50% parasite killing (50% lethal dose [LD50]). This mutation also reversed Dd2-mediated CQ …


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 May 2017

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 and Staff 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 Apr 2017

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 and Staff 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 Apr 2017

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 and Staff 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 …


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 Apr 2017

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 and Staff 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 …


What Happened To Anti-Malarial Markets After The Affordable Medicines Facility-Malaria Pilot? Trends In Act Availability, Price And Market Share From Five African Countries Under Continuation Of The Private Sector Co-Payment Mechanism., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Sarah Tougher, Kara Hanson, Catherine Goodman Apr 2017

What Happened To Anti-Malarial Markets After The Affordable Medicines Facility-Malaria Pilot? Trends In Act Availability, Price And Market Share From Five African Countries Under Continuation Of The Private Sector Co-Payment Mechanism., Kathryn A. O'Connell, Vamsi Vasireddy, Megan Littrell, Andria Rusk, Actwatch Group, Sarah Tougher, Kara Hanson, Catherine Goodman

Collected Faculty and Staff Scholarship

BACKGROUND: The private sector supplies anti-malarial treatment for large proportions of patients in sub-Saharan Africa. Following the large-scale piloting of the Affordable Medicines Facility-malaria (AMFm) from 2010 to 2011, a private sector co-payment mechanism (CPM) provided continuation of private sector subsidies for quality-assured artemisinin combination therapies (QAACT). This article analyses for the first time the extent to which improvements in private sector QAACT supply and distribution observed during the AMFm were maintained or intensified during continuation of the CPM through 2015 in Kenya, Madagascar, Nigeria, Tanzania and Uganda using repeat cross-sectional outlet survey data.

RESULTS: QAACT market share in all …


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 Apr 2017

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 and Staff 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 …


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 Apr 2017

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 and Staff 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 …


The Malaria Testing And Treatment Market In Kinshasa, Democratic Republic Of The Congo, 2013, Angela Alum, Andrew Andrada, Julie Archer, Erik Auko, Katie Bates, Paul Bouanchaud, Meghan Bruce, Angela Camilleri, Emily Carter, Steven Chapman, Nikki Charman, Desmond Chavasse, Kevin Duff, Keith Esch, Anna Fulton, Illah Evance, Anna Fulton, Helen Gataaka, Tarryn Haslam, Emily Harris, Catherine A. Hurley, Beth Kangwana, Esther Kabui, Gloria Kigo, Aliza Lailari, Megan Littrell, Erik Munroe Julius Ngigi, Kathryn A. O'Connell, Ricki Orford, Carolyne Ochieng, Linda Ongwenyi, Stephen Poyer, Justin Rahariniaina, Lanto Razafindralambo, Christina Riley, John Rodgers, Tanya Shewchuk, Julianna Smith, Tsione Solomon, Raymond Sudoi, Martine Esther Tassiba, Katherine Thanel, Andria Rusk, Rachel Thompson, Mitsuru Toda, Marie-Alix Valensi, Vamsi Vasireddy, Cynthia Whitman, Godéfroid Mpanya, Antoinette Tshefu, Joris Losimba Likwela Feb 2017

The Malaria Testing And Treatment Market In Kinshasa, Democratic Republic Of The Congo, 2013, Angela Alum, Andrew Andrada, Julie Archer, Erik Auko, Katie Bates, Paul Bouanchaud, Meghan Bruce, Angela Camilleri, Emily Carter, Steven Chapman, Nikki Charman, Desmond Chavasse, Kevin Duff, Keith Esch, Anna Fulton, Illah Evance, Anna Fulton, Helen Gataaka, Tarryn Haslam, Emily Harris, Catherine A. Hurley, Beth Kangwana, Esther Kabui, Gloria Kigo, Aliza Lailari, Megan Littrell, Erik Munroe Julius Ngigi, Kathryn A. O'Connell, Ricki Orford, Carolyne Ochieng, Linda Ongwenyi, Stephen Poyer, Justin Rahariniaina, Lanto Razafindralambo, Christina Riley, John Rodgers, Tanya Shewchuk, Julianna Smith, Tsione Solomon, Raymond Sudoi, Martine Esther Tassiba, Katherine Thanel, Andria Rusk, Rachel Thompson, Mitsuru Toda, Marie-Alix Valensi, Vamsi Vasireddy, Cynthia Whitman, Godéfroid Mpanya, Antoinette Tshefu, Joris Losimba Likwela

Collected Faculty and Staff Scholarship

Background

The Democratic Republic of Congo (DRC) is one of the two most leading contributors to the global burden of disease due to malaria. This paper describes the malaria testing and treatment market in the nation’s capital province of Kinshasa, including availability of malaria testing and treatment and relative anti-malarial market share for the public and private sector.

Methods

A malaria medicine outlet survey was conducted in Kinshasa province in 2013. Stratified multi-staged sampling was used to select areas for the survey. Within sampled areas, all outlets with the potential to sell or distribute anti-malarials in the public and private …


Geographically-Weighted Regression Of Knowledge And Behaviour Determinants To Anti-Malarial Recommending And Dispensing Practice Among Medicine Retailers In Western Kenya: Capacitating Targeted Interventions, Andria Rusk, Linda Highfield, J. Michael Wilkerson, Melissa Harrell, Andrew Obala, Benjamin Amick Nov 2016

Geographically-Weighted Regression Of Knowledge And Behaviour Determinants To Anti-Malarial Recommending And Dispensing Practice Among Medicine Retailers In Western Kenya: Capacitating Targeted Interventions, Andria Rusk, Linda Highfield, J. Michael Wilkerson, Melissa Harrell, Andrew Obala, Benjamin Amick

Collected Faculty and Staff Scholarship

Background

Most patients with malaria seek treatment first in retail drug shops. Myriad studies have examined retailer behaviours and characteristics to understand the determinants to these behaviours. Geospatial methods are helpful in discovering if geographic location plays a role in the relationship between determinants and outcomes. This study aimed to discover if spatial autocorrelation exists in the relationship between determinants and retailer behaviours, and to provide specific geographic locations and target behaviours for tailoring future interventions.

Methods

Retailer behaviours and characteristics captured from a survey deployed to medicine retailers in the Webuye Demographic and Health Surveillance Site were analysed using …


Spatial Distribution And Cluster Analysis Of Retail Drug Shop Characteristics And Antimalarial Behaviors As Reported By Private Medicine Retailers In Western Kenya: Informing Future Interventions, Andria Rusk, Linda Highfield, J. Michael Wilkerson, Melissa Harrell, Andrew Obala, Benjamin Amick Feb 2016

Spatial Distribution And Cluster Analysis Of Retail Drug Shop Characteristics And Antimalarial Behaviors As Reported By Private Medicine Retailers In Western Kenya: Informing Future Interventions, Andria Rusk, Linda Highfield, J. Michael Wilkerson, Melissa Harrell, Andrew Obala, Benjamin Amick

Collected Faculty and Staff Scholarship

Background

Efforts to improve malaria case management in sub-Saharan Africa have shifted focus to private antimalarial retailers to increase access to appropriate treatment. Demands to decrease intervention cost while increasing efficacy requires interventions tailored to geographic regions with demonstrated need. Cluster analysis presents an opportunity to meet this demand, but has not been applied to the retail sector or antimalarial retailer behaviors. This research conducted cluster analysis on medicine retailer behaviors in Kenya, to improve malaria case management and inform future interventions.

Methods

Ninety-seven surveys were collected from medicine retailers working in the Webuye Health and Demographic Surveillance Site. Survey …


Lack Of Resistance Of Plasmodium Falciparum To Dihydroartemisinin In Uganda Based On Parasitogolgical And Molecular Assays, Roland A. Cooper, Melissa D. Conrad, Quentin D. Watson, Stephanie J. Huezo, Harriet Ninsiima, Patrick Tumwebaze, Samuel L. Nsobya, Philip J. Rosenthal Oct 2015

Lack Of Resistance Of Plasmodium Falciparum To Dihydroartemisinin In Uganda Based On Parasitogolgical And Molecular Assays, Roland A. Cooper, Melissa D. Conrad, Quentin D. Watson, Stephanie J. Huezo, Harriet Ninsiima, Patrick Tumwebaze, Samuel L. Nsobya, Philip J. Rosenthal

Collected Faculty and Staff Scholarship

  • Artemisinin-­‐based combination therapy is now standard treatment for falciparum malaria. However, this regimen is threatened by resistance to artemisinins, manifest as delayed clearance of parasitemia after therapy, in southeast Asia.
  • Artemisinin resistance in southeast Asia is associated with increased parasitemias in culture, compared to those in sensi0ve parasites, 72 hours a=er a 6 hour pulse with 700 nM dihydroartemisinin (DHA), and with propeller domain polymorphisms in the Plasmodium falciparum kelch (K13; PF3D7_1343700) gene

  • Given that artemether/lumefantrine has been adopted as standard therapy for malaria within the last decade in Uganda, we characterized artemisinin sensiBvity in fresh P. falciparum isolates from …


Mutations In The Plasmodium Falciparum Chloroquine Resistance Transporter, Pfcrt, Enlarge The Parasite's Food Vacuole And Alter Drug Sensitivities, Serena Pulcini, Henry M. Staines, Andrew H. Lee, Sarah H. Shafik, Guillaume Bouyer, Catherine M. Moore, Daniel A. Daley, Matthew J. Hoke, Lindsey M. Altenhofen, Heather J. Painter, Jianbing Mu, David J. P. Ferguson, Manuel Llinas, Rowen E. Martin, David A. Fidock, Roland Cooper, Sanjeev Krishna Sep 2015

Mutations In The Plasmodium Falciparum Chloroquine Resistance Transporter, Pfcrt, Enlarge The Parasite's Food Vacuole And Alter Drug Sensitivities, Serena Pulcini, Henry M. Staines, Andrew H. Lee, Sarah H. Shafik, Guillaume Bouyer, Catherine M. Moore, Daniel A. Daley, Matthew J. Hoke, Lindsey M. Altenhofen, Heather J. Painter, Jianbing Mu, David J. P. Ferguson, Manuel Llinas, Rowen E. Martin, David A. Fidock, Roland Cooper, Sanjeev Krishna

Collected Faculty and Staff Scholarship

Mutations in the Plasmodium falciparum chloroquine resistance transporter, PfCRT, are the major determinant of chloroquine resistance in this lethal human malaria parasite. Here, we describe P. falciparum lines subjected to selection by amantadine or blasticidin that carry PfCRT mutations (C101F or L272F), causing the development of enlarged food vacuoles. These parasites also have increased sensitivity to chloroquine and some other quinoline antimalarials, but exhibit no or minimal change in sensitivity to artemisinins, when compared with parental strains. A transgenic parasite line expressing the L272F variant of PfCRT confirmed this increased chloroquine sensitivity and enlarged food vacuole phenotype. Furthermore, the introduction …


Lack Of Artemisinin Resistance In Plasmodium Falciparum In Uganda Based On Parasitological And Molecular Assays, Roland A. Cooper, Melissa D. Conrad, Quentin D. Watson, Stephanie J. Huezo, Harriet Ninsiima, Patrick Tumwebaze, Samuel L. Nsobya, Philip J. Rosenthal Aug 2015

Lack Of Artemisinin Resistance In Plasmodium Falciparum In Uganda Based On Parasitological And Molecular Assays, Roland A. Cooper, Melissa D. Conrad, Quentin D. Watson, Stephanie J. Huezo, Harriet Ninsiima, Patrick Tumwebaze, Samuel L. Nsobya, Philip J. Rosenthal

Collected Faculty and Staff Scholarship

We evaluated markers of artemisinin resistance in Plasmodium falciparum isolated in Kampala in 2014. By standard in vitro assays, all isolates were highly sensitive to dihydroartemisinin (DHA). By the ring-stage survival assay, after a 6-h DHA pulse, parasitemia was undetectable in 40 of 43 cultures at 72 h. Two of 53 isolates had nonsynonymous K13-propeller gene polymorphisms but did not have the mutations associated with resistance in Asia. Thus, we did not see evidence for artemisinin resistance in Uganda.


Impact Of Antimalarial Treatment And Chemoprevention On The Drug Sensitivity Of Malaria Parasites Isolated From Ugandan Children, Patrick Tumwebaze, Melissa D. Conrad, Andrew Walakira, Norbert Leclair, Oswald Byaruhanga, Christine Nakazibwe, Benjamin Kozak, Jessica Bloome, Jaffer Okiring, Abel Kakuru, Victor Bigira, James Kapisi, Jennifer Legac, Jiri Gut, Roland A. Cooper, Moses R. Kamya, Diane V. Havlir, Grant Dorsey, Bryan Greenhouse, Samuel L. Nsobya, Philip J. Rosenthal Mar 2015

Impact Of Antimalarial Treatment And Chemoprevention On The Drug Sensitivity Of Malaria Parasites Isolated From Ugandan Children, Patrick Tumwebaze, Melissa D. Conrad, Andrew Walakira, Norbert Leclair, Oswald Byaruhanga, Christine Nakazibwe, Benjamin Kozak, Jessica Bloome, Jaffer Okiring, Abel Kakuru, Victor Bigira, James Kapisi, Jennifer Legac, Jiri Gut, Roland A. Cooper, Moses R. Kamya, Diane V. Havlir, Grant Dorsey, Bryan Greenhouse, Samuel L. Nsobya, Philip J. Rosenthal

Collected Faculty and Staff Scholarship

Changing treatment practices may be selecting for changes in the drug sensitivity of malaria parasites. We characterized ex vivo drug sensitivity and parasite polymorphisms associated with sensitivity in 459 Plasmodium falciparum samples obtained from subjects enrolled in two clinical trials in Tororo, Uganda, from 2010 to 2013. Sensitivities to chloroquine and monodesethylamodiaquine varied widely; sensitivities to quinine, dihydroartemisinin, lumefantrine, and piperaquine were generally good. Associations between ex vivo drug sensitivity and parasite polymorphisms included decreased chloroquine and monodesethylamodiaquine sensitivity and increased lumefantrine and piperaquine sensitivity with pfcrt 76T, as well as increased lumefantrine sensitivity with pfmdr1 86Y, Y184, and 1246Y. …


Heart Rate Variability Measured Early In Patients With Evolving Acute Coronary Syndrome And 1-Year Outcomes Of Rehospitalization And Mortality, Patricia R.E. Harris, Phyllis K. Stein, Gordon L. Fung, Barbara J. Drew Aug 2014

Heart Rate Variability Measured Early In Patients With Evolving Acute Coronary Syndrome And 1-Year Outcomes Of Rehospitalization And Mortality, Patricia R.E. Harris, Phyllis K. Stein, Gordon L. Fung, Barbara J. Drew

Collected Faculty and Staff Scholarship

Objective: This study sought to examine the prognostic value of heart rate variability (HRV) measurement initiated immediately after emergency department presentation for patients with acute coronary syndrome (ACS).

Background: Altered HRV has been associated with adverse outcomes in heart disease, but the value of HRV measured during the earliest phases of ACS related to risk of 1-year rehospitalization and death has not been established.

Methods: Twenty-four-hour Holter recordings of 279 patients with ACS were initiated within 45 minutes of emergency department arrival; recordings with �18 hours of sinus rhythm were selected for HRV analysis (number [N] �193). Time domain, frequency …


Heart Rate Variability Measurement And Clinical Depression In Acute Coronary Syndrome Patients: Narrative Review Of Recent Literature, Patricia R.E. Harris, Claire E. Sommargren, Phyllis K. Stein, Gordon L. Fung, Barbara J. Drew Jul 2014

Heart Rate Variability Measurement And Clinical Depression In Acute Coronary Syndrome Patients: Narrative Review Of Recent Literature, Patricia R.E. Harris, Claire E. Sommargren, Phyllis K. Stein, Gordon L. Fung, Barbara J. Drew

Collected Faculty and Staff Scholarship

Aim: We aimed to explore links between heart rate variability (HRV) and clinical depression in patients with acute coronary syndrome (ACS), through a review of recent clinical research literature.

Background: Patients with ACS are at risk for both cardiac autonomic dysfunction and clinical depression. Both conditions can negatively impact the ability to recover from an acute physiological insult, such as unstable angina or myocardial infarction, increasing the risk for adverse cardiovascular outcomes. HRV is recognized as a reflection of autonomic function.

Methods: A narrative review was undertaken to evaluate state-of-the-art clinical research, using the PubMed database, January 2013. The search …


Prognostic Value Of Heart Rate Turbulence For Risk Assessment In Patients With Unstable Angina And Non-St Elevation Myocardial Infarction, Patricia R.E. Harris, Phyllis K. Stein, Gordon L. Fung, Barbara J. Drew Aug 2013

Prognostic Value Of Heart Rate Turbulence For Risk Assessment In Patients With Unstable Angina And Non-St Elevation Myocardial Infarction, Patricia R.E. Harris, Phyllis K. Stein, Gordon L. Fung, Barbara J. Drew

Collected Faculty and Staff Scholarship

Background: We sought to examine the prognostic value of heart rate turbulence derived from electrocardiographic recordings initiated in the emergency department for patients with non-ST elevation myocardial infarction (NSTEMI) or unstable angina.

Methods: Twenty-four-hour Holter recordings were started in patients with cardiac symptoms approximately 45 minutes after arrival in the emergency department. Patients subsequently diagnosed with NSTEMI or unstable angina who had recordings with ≥18 hours of sinus rhythm and sufficient data to compute Thrombolysis In Myocardial Infarction (TIMI) risk scores were chosen for analysis (n = 166). Endpoints were emergent re-entry to the cardiac emergency department and/or death at …


Expanding Access To Malaria Diagnosis Through Retail Shops In Western Kenya: What Do Shop Workers Think?, Andria Rusk, Catherine Goodman, Violet Naanyu, Beatrice Koech, Andrew Obala, Wendy Prudhomme O'Meara May 2013

Expanding Access To Malaria Diagnosis Through Retail Shops In Western Kenya: What Do Shop Workers Think?, Andria Rusk, Catherine Goodman, Violet Naanyu, Beatrice Koech, Andrew Obala, Wendy Prudhomme O'Meara

Collected Faculty and Staff Scholarship

Background. The common symptoms of malaria reduce the specificity of clinical diagnosis. Presumptive treatment is conventional but can lead to overdiagnosis of malaria, delay of appropriate treatment, overprescription of antimalarials, and drug resistance. Routine use of diagnostic tests can address many of these concerns. Though treatment is often procured from retailers, there is low availability of rapid diagnostic tests for malaria (MRDTs), a simple, inexpensive, and accurate diagnostic solution. We know little about the challenges to expanding access to diagnostics through these outlets. Methods. To understand the perceptions of the benefits and challenges to selling rapid diagnostic tests for malaria, …


Mutation In The Plasmodium Falciparum Crt Protein Determines The Stereospecific Activity Of Antimalarial Cinchona Alkaloids, Carol E. Griffin, Jonathan M. Hoke, Upeka Samarakoon, Junhui Duan, Jianbing Mu, Michael T. Ferdig, David C. Warhurst, Roland Cooper Oct 2012

Mutation In The Plasmodium Falciparum Crt Protein Determines The Stereospecific Activity Of Antimalarial Cinchona Alkaloids, Carol E. Griffin, Jonathan M. Hoke, Upeka Samarakoon, Junhui Duan, Jianbing Mu, Michael T. Ferdig, David C. Warhurst, Roland Cooper

Collected Faculty and Staff Scholarship

The Cinchona alkaloids are quinoline aminoalcohols that occur as diastereomer pairs, typified by (-)-quinine and (+)-quinidine. The potency of (+)-isomers is greater than the (-)-isomers in vitro and in vivo against Plasmodium falciparum malaria parasites. They may act by the inhibition of heme crystallization within the parasite digestive vacuole in a manner similar to chloroquine. Earlier studies showed that a K76I mutation in the digestive vacuole-associated protein, PfCRT (P. falciparum chloroquine resistance transporter), reversed the normal potency order of quinine and quinidine toward P. falciparum. To further explore PfCRT-alkaloid interactions in the malaria parasite, we measured the in vitro susceptibility …


Does Anti-Malarial Drug Knowledge Predict Anti-Malarial Dispensing Practice In Drug Outlets? A Survey Of Medicine Retailers In Western Kenya., Andria Rusk, Nathan Smith, Diana Menya, Andrew Obala, Chrispinus Simiyu, Barasa Khwa-Otsyula, Wendy O'Meara Aug 2012

Does Anti-Malarial Drug Knowledge Predict Anti-Malarial Dispensing Practice In Drug Outlets? A Survey Of Medicine Retailers In Western Kenya., Andria Rusk, Nathan Smith, Diana Menya, Andrew Obala, Chrispinus Simiyu, Barasa Khwa-Otsyula, Wendy O'Meara

Collected Faculty and Staff Scholarship

Background

Malaria is a major cause of morbidity and mortality in Kenya, where it is the fifth leading cause of death in both children and adults. Effectively managing malaria is dependent upon appropriate treatment. In Kenya, between 17 to 83 percent of febrile individuals first seek treatment for febrile illness over the counter from medicine retailers. Understanding medicine retailer knowledge and behaviour in treating suspected malaria and dispensing anti-malarials is crucial.

Methods

To investigate medicine retailer knowledge about anti-malarials and their dispensing practices, a survey was conducted of all retail drug outlets that sell anti-malarial medications and serve residents of …


Feasibility And Compliance With Daily Home Ecg Monitoring Of The Qt Interval In Heart Transplant Recipients, Erik V. Carter, Kathleen T. Hickey, David M. Pickham, Lynn V. Doering, Belinda Chen, Patricia Harris, Barbara J. Drew Jul 2012

Feasibility And Compliance With Daily Home Ecg Monitoring Of The Qt Interval In Heart Transplant Recipients, Erik V. Carter, Kathleen T. Hickey, David M. Pickham, Lynn V. Doering, Belinda Chen, Patricia Harris, Barbara J. Drew

Collected Faculty and Staff Scholarship

Background: Recent evidence suggests that acute allograft rejection after heart transplantation causes an increased QT interval on electrocardiogram (ECG). The aims of this pilot study were to (1) determine whether heart transplant recipients could achieve compliance in transmitting a 30-second ECG every day for 1 month using a simple ECG device and their home telephone, (2) evaluate the ease of device use and acceptability by transplant recipients, and (3) evaluate the quality of transmitted ECG tracings for QT-interval measurement.

Methods: A convenience sample of adult heart transplant recipients were recruited and trained to use the device (HeartOne, Aerotel Medical Systems, …


Chloroquine Susceptibility And Reversibility In A Plasmodium Falciparum Genetic Cross, Jigar J. Patel, Drew Thacker, Jon C. Tan, Perri Pleeter, Lisa Checkley, Joseph M. Gonzales, Bingbing Deng, Paul D. Roepe, Roland A. Cooper, Michael T. Ferdig Nov 2010

Chloroquine Susceptibility And Reversibility In A Plasmodium Falciparum Genetic Cross, Jigar J. Patel, Drew Thacker, Jon C. Tan, Perri Pleeter, Lisa Checkley, Joseph M. Gonzales, Bingbing Deng, Paul D. Roepe, Roland A. Cooper, Michael T. Ferdig

Collected Faculty and Staff Scholarship

Mutations in the Plasmodium falciparum chloroquine (CQ) resistance transporter (PfCRT), are major determinants of verapamil (VP)-reversible CQ resistance (CQR). In the presence of mutant PfCRT, additional genes contribute to the wide range of CQ susceptibilities observed. It is not known if these genes influence mechanisms of chemosensitization by CQR reversal agents. Using quantitative trait locus (QTL) mapping of progeny clones from the HB3 × Dd2 cross, we show that the P. falciparum multidrug resistance gene 1 (pfmdr1) interacts with the Southeast Asiaderived mutant pfcrt haplotype to modulate CQR levels. A novel chromosome 7 locus is predicted to contribute with the …


Accumulation Of Artemisinin Trioxane Derivatives Within Neutral Lipids Of Plasmodium Falciparum Malaria Parasites Is Endoperoxide-Dependent, Carmony L. Hartwig, Andrew S. Rosenthal, John D'Angelo, Carol E. Griffin, Gary H. Posner, Roland A. Cooper Feb 2009

Accumulation Of Artemisinin Trioxane Derivatives Within Neutral Lipids Of Plasmodium Falciparum Malaria Parasites Is Endoperoxide-Dependent, Carmony L. Hartwig, Andrew S. Rosenthal, John D'Angelo, Carol E. Griffin, Gary H. Posner, Roland A. Cooper

Collected Faculty and Staff Scholarship

The antimalarial trioxanes, exemplified by the naturally occurring sesquiterpene lactone artemisinin and its semi-synthetic derivatives, contain an endoperoxide pharmacophore that lends tremendous potency against Plasmodium parasites. Despite decades of research, their mechanism of action remains unresolved. A leading model of anti-plasmodial activity hypothesizes that iron-mediated cleavage of the endoperoxide bridge generates cytotoxic drug metabolites capable of damaging cellular macromolecules. To probe the malarial targets of the endoperoxide drugs, we studied the distribution of fluorescent dansyl trioxane derivatives in living, intraerythrocytic-stage Plasmodium falciparum parasites using microscopic imaging. The fluorescent trioxanes rapidly accumulated in parasitized erythrocytes, localizing within digestive vacuole-associated neutral lipid …


Genome-Wide Compensatory Changes Accompany Drug Selected Mutations In The Plasmodium Falciparum Crt Gene, Hongying Jiang, Jigar J. Patel, Ming Yi, Jianbing Mu, Jinhui Ding, Robert Stephens, Roland Cooper, Michael T. Ferdig, Xin-Zhuan Su Jun 2008

Genome-Wide Compensatory Changes Accompany Drug Selected Mutations In The Plasmodium Falciparum Crt Gene, Hongying Jiang, Jigar J. Patel, Ming Yi, Jianbing Mu, Jinhui Ding, Robert Stephens, Roland Cooper, Michael T. Ferdig, Xin-Zhuan Su

Collected Faculty and Staff Scholarship

Mutations in PfCRT (Plasmodium falciparum chloroquine-resistant transporter), particularly the substitution at amino acid position 76, confer chloroquine (CQ) resistance in P. falciparum. Point mutations in the homolog of the mammalian multidrug resistance gene (pfmdr1) can also modulate the levels of CQ response. Moreover, parasites with the same pfcrt and pfmdr1 alleles exhibit a wide range of drug sensitivity, suggesting that additional genes contribute to levels of CQ resistance (CQR). Reemergence of CQ sensitive parasites after cessation of CQ use indicates that changes in PfCRT are deleterious to the parasite. Some CQR parasites, however, persist in the field and grow well …