A5009921592- HIV Research and Treatment
- HIV/AIDS Research and Interventions
- Reproductive tract infections research
- HIV-related health complications and treatments
- Immune Cell Function and Interaction
- Sex work and related issues
- Child Nutrition and Water Access
- Reproductive System and Pregnancy
- SARS-CoV-2 and COVID-19 Research
- Hepatitis B Virus Studies
- Tuberculosis Research and Epidemiology
- Virology and Viral Diseases
- Viral Infections and Vectors
- Pneumocystis jirovecii pneumonia detection and treatment
- Adolescent Sexual and Reproductive Health
- Hepatitis C virus research
- COVID-19 epidemiological studies
- Global Maternal and Child Health
- Food Security and Health in Diverse Populations
- Phytochemistry and Biological Activities
- Respiratory viral infections research
- Rabies epidemiology and control
- vaccines and immunoinformatics approaches
- Poxvirus research and outbreaks
- Viral Infections and Outbreaks Research
University of Nairobi
2015-2024
Washington State University
2023-2024
University of Manitoba
2011-2024
Charité - Universitätsmedizin Berlin
2024
German Center for Infection Research
2024
University of Edinburgh
2024
Mbarara University of Science and Technology
2024
Queen Mary University of London
2024
Partners for Health and Development in Africa
2018-2023
HealthRight International
2023
Many people who remain persistently seronegative despite frequent HIV exposure have HIV-specific immune responses. The study of these may provide information about mechanisms natural protective immunity to HIV-1. We describe the specificity cytotoxic T lymphocyte responses in prostitutes Nairobi are apparently resistant infection. These women had a range African HIV-1 variants, primarily clades A, C, and D, for up 12 yr without becoming infected. Nearly half them CTL directed towards...
Certain human leukocyte antigens, by presenting conserved immunogenic epitopes for T cell recognition, may, in part, account the observed differences immunodeficiency virus type 1 (HIV-1) susceptibility. To determine whether HLA polymorphism influences HIV-1 susceptibility, a longitudinal cohort of highly HIV-1—exposed female sex workers based Nairobi, Kenya, was prospectively analyzed. Decreased infection risk strongly associated with possession cluster closely related alleles (A2/6802...
HIV-1–specific cytotoxic T-lymphocyte (CTL) responses have been detected at a low frequency in many HIV-1–exposed, persistently seronegative (HEPS) subjects. However, it is unclear how CTLs could protect against HIV acquisition HEPS subjects, when high levels of circulating CTL fail to prevent disease progression most seropositive To address this issue we studied CD8+ lymphocyte panel HIV-1 epitopes 91 and 87 HIV-1–infected Nairobi sex workers. HIV-specific women focused strongly on rarely...
Among 302 female sex workers in Nairobi, Kenya, who were followed for 17.6 ± 11.1 months, 146 had one or more infections with Chlamydia trachomatis; 102 uncomplicated cervical infection only, 23 C. trachomatis pelvic inflammatory disease (PID), and 21 combined Neisseria gonorrhoeae PID. As determined by multivariate logistic regression analysis, risk factors PID included repeated (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.3–2.4; P = .0004),antibody to heat-shock protein 60 (OR,...
Over the last decade, Kenyan HIV treatment program has grown exponentially, with improved survival among people living (PLHIV). In same period, noncommunicable diseases (NCDs) have become a leading contributor to disease burden. We sought characterize burden of four major NCDs (cardiovascular diseases, cancer, chronic respiratory and diabetes mellitus) adult PLHIV in Kenya. conducted nationally representative retrospective medical chart review HIV-infected adults aged ≥15 years enrolled care...
Tuberculosis (TB) causes substantial morbidity and mortality in HIV-infected children. Sample collection the paucibacillary nature of TB children makes diagnosis challenging. Rapid diagnostic tools using easily obtained specimens are urgently needed.Hospitalized, aged 12 years or less enrolled a randomized controlled trial (NCT02063880) comparing urgent to post-stabilization antiretroviral therapy initiation Kenya underwent evaluation. At enrollment, sputum gastric aspirates were collected...
Genital immunology is a key determinant of human immunodeficiency virus (HIV) susceptibility. Both factors are modulated by bacterial vaginosis (BV) and, to some extent, Lactobacillus iners, the genital spp. that predominates in African, Caribbean, and other Black (ACB) women. We conducted clinical trial assess impact oral metronidazole treatment on immune parameters HIV acquisition risks Kenyan women with BV. The primary endpoint was ex vivo cervical CD4+ T-cell susceptibility after 1...
Abstract Background The Quinine tree ( Rauvolfia caffra ) is used as a medicinal plant among traditional communities in many countries to manage tumors and other diseases associated with oxidative stress. To validate indigenous knowledge possibly position this herb for technology uptake utilization, we established the level of antioxidant activity R. , probed presence phytochemicals. Methods Antioxidant was determined on 1,1-diphenyl-2-picrylhydrazyl (DPPH) while major phytochemicals were...
Objective To compare the vaginal microbiota of women engaged in high-risk sexual behaviour (sex work) with who are not behaviour. Diverse microbiota, low Lactobacillus species, like those bacterial vaginosis (BV), associated increased prevalence sexually transmitted infections (STIs) and human immunodeficiency virus (HIV) acquisition. Although increases risk for STIs, sex workers is understudied. Methods A retrospective cross-sectional study was conducted comparing work (non-sex worker...
Viral hepatitis is a major concern worldwide, with A (HAV) and E (HEV) viruses showing sporadic outbreaks while B (HBV) C (HCV) are associated chronic hepatitis, cirrhosis hepatocellular carcinoma. The present study determined the proportion, geographic distribution molecular characterization of among patients seeking medical services at hospitals throughout Kenya. Patients presenting jaundice four selected were recruited (n = 389). Sera tested for presence antibody to through E, HBV surface...
Abstract Middle East respiratory syndrome coronavirus (MERS-CoV) is endemic in dromedaries Africa, but camel-to-human transmission limited. Sustained 12-month sampling of a Kenya abattoir hub showed biphasic MERS-CoV incidence; peak detections occurred October 2022 and February 2023. Dromedary-exposed workers (7/48) had serologic signs previous exposure.
The goal of the present study was to determine whether there were HIV‐1 specific cellular immune responses among a subgroup women within cohort Nairobi prostitutes ( n = 1800) who, despite their intense sexual exposure HIV‐1, are epidemiologically resistant infection. Of 80 defined be resistant, 24 recruited for immunological evaluation. HIV‐1‐specific T‐helper determined by IL‐2 production following stimulation with envelope peptides and soluble gp120. Cytotoxic T lymphocyte lysis...
LAG-3 is a potent negative regulator of the immune response but its impact in HIV infection poorly understood. Unlike exhaustion markers such as PD-1, Tim-3, 2B4 and CD160, expressed on bulk antigen-specific T cells during chronic expression innate lymphocyte subsets not well The aim this study was to assess association with cellular dysfunction cells, NK iNKT among cohort healthy HIV-infected female sex workers Nairobi, Kenya.Ex vivo measured by multiparametric flow cytometry, plasma...
The hormonal contraceptive medroxyprogesterone acetate (MPA) is associated with increased risk of human immunodeficiency virus (HIV), via incompletely understood mechanisms. Increased diversity in the vaginal microbiota modulates genital inflammation and HIV-1 acquisition. However, effect MPA on relatively unknown. In a cohort female Kenyan sex workers, negative for sexually transmitted infections (STIs), Nugent scores <7 (N=58 370 screened), correlated significantly as assessed by 16S rRNA...
A small group of women (n = 80) within the Nairobi-based Pumwani Sex Workers Cohort demonstrates epidemiologic resistance to HIV-1 infection. Chemokine receptor polymorphisms and β-chemokine overproduction have been among mechanisms suggested be responsible for This study attempts determine if any those are protecting HIV-1-resistant women. Genetic analysis CCR5 CCR3 from resistant demonstrated no associated with resistance. Expression levels were shown equivalent that found in low-risk...
Depot medroxyprogesterone acetate (DMPA) is an injectable hormonal contraceptive used by millions of women worldwide. However, experimental studies have associated DMPA use with genital epithelial barrier disruption and mucosal influx human immunodeficiency virus (HIV) target cells. We explored the underlying molecular mechanisms these findings. Ectocervical biopsies cervicovaginal lavage (CVL) specimens were collected from HIV-seronegative Kenyan sex workers using ( n = 32) or regularly...
The majority of Kenya’s > 3 million camels have antibodies against Middle East respiratory syndrome coronavirus (MERS-CoV), although human infection in Africa is rare. We enrolled 243 aged 0–24 months from 33 homesteads Northern Kenya and followed them between April 2018 to March 2020. collected tested camel nasal swabs for MERS-CoV RNA by RT-PCR virus isolation whole genome sequencing positive samples. also documented illnesses (respiratory or other) among the camels. Human handlers were...
Background: Persons with HIV (PWH) on antiretroviral therapy (ART) have persistent immune activation associated increased risk for non-AIDS related diseases. Latent tuberculosis infection (LTBI), endemic in Africa, may contribute to this dysregulation. We evaluated the impact of and TB co-infection plasma pro- anti-inflammatory cytokines among Kenyan adults. Methods: compared data from 221 PWH long-term ART 177 HIV-negative adults examining biomarkers pro-[sCD14, interleukin (IL)-2, IL-6,...
Human leukocyte antigen (HLA) molecules regulate the cellular immune system and may be determinants of infant susceptibility to human immunodeficiency virus type 1 (HIV-1) infection. Molecular HLA typing for class I alleles was performed on infants followed in a Kenyan perinatal cohort. Early HIV-1 infection status defined as occurring at birth or month 1, while late via breast milk first detection after age. Likelihood ratio tests based proportional hazards model adjusting maternal CD4 T...
Abstract Introduction At its basic level, HIV infection requires a replication‐competent virus and susceptible target cell. Elevated levels of vaginal inflammation has been associated with the increased risk as it brings highly activated cells (CCR5+CD4+ T cells; CCR5+CD4+CD161+ Th17 cells) to female genital tract (FGT) where they interact HIV. Decreased phenotype decreased immune activation, called quiescence, described among Kenyan sex workers who were intensely exposed yet remain...
Health care systems in sub-Saharan Africa, and globally, grapple with the problem of closing gap between evidence-based health interventions actual practice service settings. It is essential for systems, especially low-resource settings, to increase capacity implement practices, by training professionals implementation science. With support from Medical Education Partnership Initiative, University Nairobi has developed a program build local This paper describes how leveraged resources...