A5038743021- Mosquito-borne diseases and control
- Malaria Research and Control
- Viral Infections and Vectors
- Vector-borne infectious diseases
- Viral Infections and Outbreaks Research
- Leptospirosis research and findings
- Insect Utilization and Effects
- Dengue and Mosquito Control Research
- Fire effects on ecosystems
- Computational Drug Discovery Methods
- Education, Sociology, Communication Studies
- Protein purification and stability
- Aquatic Ecosystems and Phytoplankton Dynamics
- Drug-Induced Hepatotoxicity and Protection
- Financial Literacy, Pension, Retirement Analysis
- Algal biology and biofuel production
- Disaster Response and Management
- Microfinance and Financial Inclusion
- Plant Virus Research Studies
- Insect Pest Control Strategies
- Vector-Borne Animal Diseases
- Fish biology, ecology, and behavior
- Hemoglobinopathies and Related Disorders
- Marine and coastal ecosystems
- Travel-related health issues
Armed Forces Research Institute of Medical Science
2017-2024
Walter Reed Army Institute of Research
2010-2024
Uniformed Services University of the Health Sciences
2020-2022
United States Army
2017-2018
Naval Medical Research Command
2018
United States Army Medical Research Directorate - Africa
2013-2017
Kenya Medical Research Institute
2013-2016
United States Department of the Army
2006
Single Nucleotide Polymorphisms (SNPs) in the Pfmdr1, and Pfcrt, genes of Plasmodium falciparum may confer resistance to a number anti-malaria drugs. Pfmdr1 86Y haplotypes at Pfcrt 72-76 have been linked chloroquine (CQ) as well amodiaquine (AQ) resistance. mefloquine (MQ) lumefantrine (LU) sensitivities are 86Y. Additionally, K76 allele carrying parasites shown tolerance LU. We investigated association between 86/Pfcrt P. CQ, AQ, MQ LU using field samples collected during 2008–2011 from...
Malaria continues to be a major burden in the endemic regions of Kenya. Health outcomes associated with case management are dependent on use appropriate diagnostic methods. Rapid tests (RDTs) have provided an important tool help implement WHO recommended parasite-based diagnosis where expert microscopy is not available. One questions that must answered when implementing RDTs whether these useful specific region, as well most RDT use. Data sensitivity and specificity test kits information...
We present data that concurs with the reported geographical expansion of scrub typhus outside “Tsutsugamushi Triangle” and addition Orientia chuto as a second species in genus. Wild rodents were caught Marigat, Baringo County, Kenya, ectoparasites, including chiggers, recovered.
Malaria diagnosis is largely dependent on the demonstration of parasites in stained blood films by conventional microscopy. Accurate identification infecting Plasmodium species relies detailed examination parasite morphological characteristics, such as size, shape, pigment granules, besides size and shape parasitized red cells presence cell inclusions. This work explores misclassifications four microscopy relative to proficiency microscopists characteristics Giemsa-stained films. Ten-day...
Malaria accounts for ~21% of outpatient visits annually in Kenya; prompt and accurate malaria diagnosis is critical to ensure proper treatment. In 2013, formal microscopy refresher training microscopists a pilot quality-assurance (QA) programme diagnostics were independently implemented improve low-transmission areas Kenya. A study was conducted identify factors associated with performance the same areas. From March April 2014, cross-sectional survey 42 public health facilities; 21 QA-pilot...
We conducted experiments to investigate the importance of algal food resources for larval growth and adult emergence Anopheles gambiae Giles s.s. in simulated habitats Kenya, greenhouse laboratory microcosms United States. In first experiment, we used shading reduce biomass, because production development might be a function underlying soil nutrients, crossed sun-shade treatments with soils two distinct types collected near habitats. Shading reduced pupation rates total biomass An. by...
Plasmodium ovale is comprised of two genetically distinct subspecies, P. curtisi and wallikeri. Although subspecies are similar based on morphology geographical distribution, allelic differences indicate that wallikeri divergent. Additionally, potential clinical latency duration between demonstrate the need for investigation into contribution this neglected malaria parasite to global burden.In order detect all simultaneously, we developed an inclusive ovale-specific real-time PCR assay...
Investigation of a scrub typhus outbreak in Thailand during September 2013 found that 9.1% Thai soldiers and 11.1% residents living areas surrounding training sites had antibodies against the causative agent, Orientia tsutsugamushi. Sequence analysis O. tsutsugamushi from rodents chiggers identified 7 genogroups 3 genotypes.
All traditional surveillance techniques for Aedes aegypti have been developed the cosmopolitan domestic subspecies Ae. aegypti, and not sylvatic subspecies, formosus. The predominant form in Western Kenya is formosus that rarely associated with human habitations but linked to transmission of dengue virus strains. We compared five methods their effectiveness sampling goal determining a sustainable strategy Kenya. included larval pupal surveys, oviposition trapping, BG-Sentinel resting boxes,...
One objective of the Kenya National Malaria Strategy 2009–2017 is scaling access to prompt diagnosis and effective treatment. In 2013, a quality assurance (QA) pilot was implemented improve accuracy malaria diagnostics at selected health facilities in low-transmission counties Kenya. Trends diagnostic QA indicator performance during are described. From June December 28 officers provided on-the-job training mentoring for microscopy, rapid tests laboratory QA/quality control (QC) practices...
Prior to the devastating earthquake in Nepal 2015, scrub typhus was not recognized as a highly endemic disease country. This contrasted with neighboring India, where is and there have been sporadic outbreaks of severe forms. discrepancy underscores limitations our comprehensive understanding epidemiological patterns Nepal, especially before 2015. To better understand dynamic current status typhus, this study investigated its prevalence among patients acute febrile illness two hospitals...
Rift Valley fever virus (RVFV) causes outbreaks of severe disease in domestic ungulates as well humans Africa. There is a concern that may continue and this spread into regions where it had not previously been detected. Surveillance rapid detection are critical to the initiation an effective control program. Here we report on field evaluation Kenya VectorTest® RVFV antigen assay, modeled VecTest® assay for West Nile virus. The dipsticks provided results <20 min, were easy use, did require...
Successful mating by male mosquitoes is dependent on several factors, with sugar feeding being particularly important. The effect of ingested vitamins adult poorly understood. This laboratory study used 3 anopheline species, Anopheles campestris, An. dirus, and sawadwongporni, to the longevity, copulation, fecundity. Males were fed 1 5 diets containing different combinations vitamins: 10% glucose, sucrose, multivitamin syrup, syrup + sucrose. longevity males was measured for a period 15...
Tick-borne diseases (TBDs) pose a significant risk to humans and represent one of the major factors influencing readiness within United States' military worldwide. Additionally, ticks TBDs constitute animal health problems leading economic losses at multiple levels affecting low- middle-income countries hardest. Tick control is frequently hampered by issues ranging from acaricide resistance lack data on tick distribution infection rates. We conducted cross-sectional study assess species...
Leptospirosis is a neglected zoonotic disease affecting mostly the world's tropical regions. The rural people of northeastern Thailand suffer from large number leptospirosis infections, and their abundant rice fields are optimal rodent habitats. To evaluate contribution diversity carriage rate pathogenic Leptospira in reservoirs to incidence, we surveyed rodents, between 2011 2012, four provinces with highest incidence rates human cases. We used lipL32 real-time PCR detect kidneys, partial...
Early and accurate diagnosis of malaria is important in treatment as well the clinical evaluation drugs vaccines. Evaluation Giemsa-stained smears remains gold standard for diagnosis, although diagnostic errors potential bias estimates protective efficacy have been reported practice. Plasmodium genus fluorescent situ hybridization (P-Genus FISH) a microscopy-based method that uses labelled oligonucleotide probes targeted to pathogen specific ribosomal RNA fragments detect parasites whole...
There is a threat for dengue virus (DENV) reemergence in many regions of the world, particularly areas where DENV vectors, Aedes aegypti (L.) and albopictus (Skuse), are readily available. However, there currently no accurate reliable diagnostic methods to provide critical, real-time information early detection within vector populations implement appropriate control personal protective measures. In this article, we report ability an immuno-chromatographic assay developed by VecTOR Test...
Malaria rapid diagnostic tests (RDTs) are a great achievement in implementation of parasite based diagnosis as recommended by World Health Organization. A major drawback RDTs is lack positive controls to validate different batches/lots at the point care. Dried Plasmodium falciparum-infected samples with RDT target antigens have been suggested possible control but their utility resource limited settings hampered loss activity over time. This study evaluated effectiveness chemical additives...
Background: Identifying effective malaria elimination strategies for remote forested regions in Southeast Asia is challenging given limited resources. In this study, two were evaluated partnership with the Royal Cambodian Armed Forces - monthly prophylaxis (MMP) and focused screening treatment (FSAT). Methods: Eight primarily military clusters (1,050 volunteers total) along Cambodian-Thai border randomized to 3 months of MMP or FSAT testing by RDT, PCR, microscopy six months. Clusters...
Leptospirosis, a global zoonotic disease caused by Leptospira spp., presents high morbidity and mortality risks, especially in tropical regions like Thailand. Military personnel deployed endemic areas, such as during the Cobra Gold Joint exercise, face heightened exposure. This study assessed Leptospira's prevalence rodents environmental reservoirs at military training sites from 2017 to 2022. A surveillance program was conducted Engineering Civil Assistance Program (ENCAP) using real-time...
The Anopheles Hyrcanus Group in the Republic of Korea (ROK) consists 5 morphologically indistinct species that can only be identified with certainty by polymerase chain reaction (PCR). A total 86 bloodfed spp. were collected from a cow barn located village Tongilchon near demilitarized zone ROK on June 13, 2016, and sent to Armed Forces Research Institute Medical Sciences Bangkok, Thailand, where they PCR. 1st shipment contained 15 An. belenrae 37 pullus females used start colonies. Parent...