Phelgona Otieno
Kenya Medical Research Institute
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Pediatric Infectious Disease Journal | 2004
Elizabeth Obimbo; Dorothy Mbori-Ngacha; James Ochieng; Barbra A. Richardson; Phelgona Otieno; Rose Bosire; Carey Farquhar; Julie Overbaugh; Grace John-Stewart
Background: Pediatric human immunodeficiency virus type 1 (HIV-1) infection follows a bimodal clinical course with rapid progression in 10–45% of children before the age of 2 years and slower progression in the remainder. A prospective observational study was undertaken to determine predictors of mortality in HIV-1-infected African infants during the first 2 years of life. Methods: Infants in a perinatal cohort identified to be HIV-1-infected by DNA PCR were followed monthly to 1 year, then quarterly to 2 years or death. Results: Among 62 HIV-1-infected infants, infection occurred by the age of 1 month in 56 (90%) infants, and 32 (52%) died at median age of 6.2 months. All infant deaths were caused by infectious diseases, most frequently pneumonia (75%) and diarrhea (41%). Univariate predictors of infant mortality included maternal CD4 count <200 cells/μl [hazard ratio (HR), 3.4; P = 0.008], maternal anemia (HR = 3.7; P = 0.005), delivery complications (HR = 2.7; P = 0.01), low birth weight (HR = 4.1; P = 0.001), weight, length and head circumference ≤5th percentile at age 1 month (HR = 3.7, P = 0.003; HR = 5.8, P < 0.001; and HR = 10.4, P < 0.001, respectively), formula-feeding (HR = 4.0; P = 0.01), infant CD4% ≤15% (HR = 5.5; P = 0.01), infant CD4 count <750 (HR = 9.7; P = 0.006) and maternal death (HR = 2.9, P = 0.05). In multivariate analysis, maternal CD4 count <200 (HR = 2.7; P = 0.03) and delivery complications (HR = 3.4; P = 0.005) were independently associated with infant mortality. Conclusions: Advanced maternal HIV disease, maternal anemia, delivery complications, early growth faltering, formula-feeding and low infant CD4 were predictors of early mortality in African HIV-1-infected infants. In resource-poor settings, these predictors may be useful for early identification and treatment of high risk infants.
AIDS | 2008
Judd L. Walson; Phelgona Otieno; Margaret Mbuchi; Barbra A. Richardson; Barbara Lohman-Payne; Steve Wanyee Macharia; Julie Overbaugh; James A. Berkley; Eduard J. Sanders; Michael H Chung; Grace John-Stewart
Objective:Several co-infections have been shown to impact the progression of HIV-1 infection. We sought to determine if treatment of helminth co-infection in HIV-1-infected adults impacted markers of HIV-1 disease progression. Design:To date, there have been no randomized trials to examine the effects of soil-transmitted helminth eradication on markers of HIV-1 progression. Methods:A randomized, double-blind, placebo-controlled trial of albendazole (400 mg daily for 3 days) in antiretroviral-naive HIV-1-infected adults (CD4 cell count >200 cells/μl) with soil-transmitted helminth infection was conducted at 10 sites in Kenya (Clinical Trials.gov NCT00130910). CD4 and plasma HIV-1 RNA levels at 12 weeks following randomization were compared in the trial arms using linear regression, adjusting for baseline values. Results:Of 1551 HIV-1-infected individuals screened for helminth infection, 299 were helminth infected. Two hundred and thirty-four adults were enrolled and underwent randomization and 208 individuals were included in intent-to-treat analyses. Mean CD4 cell count was 557 cells/μl and mean plasma viral load was 4.75 log10 copies/ml at enrollment. Albendazole therapy resulted in significantly higher CD4 cell counts among individuals with Ascaris lumbricoides infection after 12 weeks of follow-up (+109 cells/μl; 95% confidence interval +38.9 to +179.0, P = 0.003) and a trend for 0.54 log10 lower HIV-1 RNA levels (P = 0.09). These effects were not seen with treatment of other species of soil-transmitted helminths. Conclusion:Treatment of A. lumbricoides with albendazole in HIV-1-coinfected adults resulted in significantly increased CD4 cell counts during 3-month follow-up. Given the high prevalence of A. lumbricoides infection worldwide, deworming may be an important potential strategy to delay HIV-1 progression.
Aids Care-psychological and Socio-medical Aspects of Aids\/hiv | 2010
Phelgona Otieno; Pamela K. Kohler; Rose Bosire; Elizabeth R. Brown; Steven W. Macharia; Grace John-Stewart
Abstract Background. As prevention of mother-to-child transmission of HIV (PMTCT) programs and HIV treatment programs rapidly expand in parallel, it is important to determine factors that influence the transition of HIV-infected women from maternal to continuing care. Design. This study aimed to determine rates and co-factors of accessing HIV care by HIV-infected women exiting maternal care. A cross-sectional survey of women who had participated in a PMTCT research study and were referred to care programs in Nairobi, Kenya was conducted. Methods. A median of 17 months following referral, women were located by peer counselors and interviewed to determine whether they accessed HIV care and what influenced their care decisions. Fishers exact test was used to assess the association between client characteristics and access to care. Results. Peer counselors traced 195 (82%) residences, where they located 116 (59%) participants who provided information on care. Since exit, 50% of participants had changed residence, and 74% reported going to the referral HIV program. Reasons for not accessing care included lack of money, confidentiality, and dislike of the facility. Women who did not access care were less likely to have informed their partner of the referral (p=0.001), and were less likely believe that highly active antiretroviral therapy (HAART) is effective (p<0.01). Among those who accessed care, 33% subsequently discontinued care, most because they did not qualify for HAART. Factors cited as barriers to access included stigma, denial, poor services, and lack of money. Factors that were cited as making care attractive included health education, counseling, free services, and compassion. Conclusion. A substantial number of women exiting maternal care do not transit to HIV care programs. Partner involvement, a standardized referral process and more comprehensive HIV education for mothers diagnosed with HIV during pregnancy may facilitate successful transitions between PMTCT and HIV care programs.
The Journal of Infectious Diseases | 2009
Grace John-Stewart; Dorothy Mbori-Ngacha; Barbara Lohman Payne; Carey Farquhar; Barbra A. Richardson; Sandra Emery; Phelgona Otieno; Elizabeth Obimbo; Tao Dong; Jennifer A. Slyker; Ruth Nduati; Julie Overbaugh; Sarah Rowland-Jones
BACKGROUND Breast-feeding by infants exposed to human immunodeficiency virus type 1 (HIV-1) provides an opportunity to assess the role played by repeated HIV-1 exposure in eliciting HIV-1-specific immunity and in defining whether immune responses correlate with protection from infection. METHODS Breast-feeding infants born to HIV-1-seropositive women were assessed for HLA-selected HIV-1 peptide-specific cytotoxic T lymphocyte interferon (IFN)-gamma responses by means of enzyme-linked immunospot (ELISpot) assays at 1, 3, 6, 9, and 12 months of age. Responses were deemed to be positive when they reached > or = 50 HIV-1-specific sfu/1 x 10(6) peripheral blood mononuclear cells (PBMCs) and were at least twice those of negative controls. RESULTS A total of 807 ELISpot assays were performed for 217 infants who remained uninfected with HIV-1 at approximately 12 months of age; 101 infants (47%) had at least 1 positive ELISpot result (median, 78-170 sfu/1 x 10(6) PBMCs). The prevalence and magnitude of responses increased with age (P = .01 and P = .007, respectively); the median log(10) value for HIV-1-specific IFN-gamma responses increased by 1.0 sfu/1 x 10(6) PBMCs/month (P < .001) between 1 and 12 months of age. Of 141 HIV-1-uninfected infants with 1-month ELISpot results, 10 (7%) acquired HIV-1 infection (0/16 with positive vs. 10/125 [8%] with negative ELISpot results; P = .6). Higher values for log(10) HIV-1-specific spot-forming units at 1 month of age were associated with a decreased risk of HIV-1 infection, adjusted for maternal HIV-1 RNA level (adjusted hazard ratio, 0.09 [95% confidence interval, 0.01-0.72]). CONCLUSION . Breast-feeding HIV-1-exposed uninfected infants frequently had HIV-1-specific IFN-gamma responses. Greater early HIV-1-specific IFN-gamma responses were associated with decreased HIV-1 acquisition.
AIDS Research and Human Retroviruses | 2004
Carey Farquhar; Sarah Rowland-Jones; Dorothy Mbori-Ngacha; Mary W. Redman; Barbara L. Lohman; Jennifer A. Slyker; Phelgona Otieno; Elizabeth Obimbo; Timothy Rostron; James Ochieng; Julius Oyugi; Rose Bosire; Grace John-Stewart
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 was defined as infection occurring at birth or month 1, while late infection via breast milk was defined as first detection of HIV-1 after 1 month of age. Likelihood ratio tests based on a proportional hazards model adjusting for maternal CD4 T cell count and HIV-1 viral load at 32 weeks of gestation were used to test associations between infant allelic variation and incident HIV-1 infection. Among 433 infants, 76 (18%) were HIV-1 infected during 12 months of follow-up. HLA B*18 was associated with a significantly lower risk of early HIV-1 transmission [relative risk (RR) = 0.26; 95% confidence interval (CI) 0.04-0.82], and none of the 24 breastfeeding infants expressing HLA B*18 who were uninfected at month 1 acquired HIV-1 late via breast milk. We observed a trend toward increased early HIV-1 acquisition for infants presenting HLA A*29 (RR = 2.0; 95% CI 1.0-3.8) and increased late HIV-1 acquisition via breast milk for both Cw*07 and Cw*08 (RR = 4.0; 95% CI 1.0-17.8 and RR = 7.2; 95% CI 1.2-37.3, respectively). HLA B*18 may protect breast-feeding infants against both early and late HIV-1 acquisition, a finding that could have implications for the design and monitoring of HIV-1 vaccines targeting cellular immune responses against HIV-1.
The Journal of Infectious Diseases | 2007
Phelgona Otieno; Elizabeth R. Brown; Dorothy Mbori-Ngacha; Ruth Nduati; Carey Farquhar; Elizabeth Obimbo; Rose Bosire; Sandy Emery; Julie Overbaugh; Barbra A. Richardson; Grace John-Stewart
BACKGROUND There is conflicting evidence regarding the effects of breast-feeding on maternal mortality from human immunodeficiency virus type 1 (HIV-1) infection, and little is known about the effects of breast-feeding on markers of HIV-1 disease progression. METHODS HIV-1-seropositive women were enrolled during pregnancy and received short-course zidovudine. HIV-1 RNA levels and CD4 cell counts were determined at baseline and at months 1, 3, 6, 12, 18, and 24 postpartum and were compared between breast-feeding and formula-feeding mothers. RESULTS Of 296 women, 98 formula fed and 198 breast-fed. At baseline, formula-feeding women had a higher education level and prevalence of HIV-1-related illness than did breast-feeding women; however, the groups did not differ with respect to CD4 cell counts and HIV-1 RNA levels. Between months 1 and 24 postpartum, CD4 cell counts decreased 3.9 cells/ microL/month (P<.001), HIV-1 RNA levels increased 0.005 log(10) copies/mL/month (P=.03), and body mass index (BMI) decreased 0.03 kg/m(2)/month (P<.001). The rate of CD4 cell count decline was higher in breast-feeding mothers (7.2 cells/ microL/month) than in mothers who never breast-fed (4.0 cells/ microL/month) (P=.01). BMI decreased more rapidly in breast-feeding women (P=.04), whereas HIV-1 RNA levels and mortality did not differ significantly between breast-feeding and formula-feeding women. CONCLUSIONS Breast-feeding was associated with significant decreases in CD4 cell counts and BMI. HIV-1 RNA levels and mortality were not increased, suggesting a limited adverse impact of breast-feeding in mothers receiving extended care for HIV-1 infection.
AIDS | 2007
Barbra A. Richardson; Phelgona Otieno; Dorothy Mbori-Ngacha; Julie Overbaugh; Carey Farquhar; Grace John-Stewart
Objective: To assess the immediate and longer-term effects of the use of hormonal contraception on the progression of HIV-1 disease in postpartum women. Design: A prospective cohort study. Methods: Information on contraceptive use, breastfeeding and intercurrent illnesses was obtained from HIV-infected postpartum Kenyan women monthly in the first year postpartum and quarterly in the second year. Blood was collected for T-cell subset analyses and HIV-1-RNA levels at months 1, 3, 6, 9, 12, 18, and 24 postpartum. The immediate effect of the initiation of oral contraceptive pills (OCP) and depot medroxyprogesterone acetate (DMPA) was assessed by comparing the change in the HIV-1-RNA plasma viral load and CD4 T-cell counts among women remaining off these contraceptive methods with those initiating them. The longer-term effects of OCP and DMPA on disease progression were assessed using Loess curves and linear mixed effects models to compare changes over the first 24 months postpartum in these same disease progression markers. Results: There were no significant immediate or longer-term effects of the use of OCP or DMPA on HIV-1-RNA plasma viral loads and CD4 T-cell counts in this cohort of HIV-infected postpartum Kenyan women. Conclusion: Comprehensive contraceptive counselling for HIV-1-infected women requires an understanding of the effects of various contraceptive methods on HIV-1 disease progression. In this study, hormonal contraception reassuringly had no immediate or longer-term effects on the rate of disease progression in chronically HIV-1-infected postpartum women. This highly effective family planning method may provide a useful and safe option for the prevention of mother-to-child transmission of HIV-1.
The Journal of Infectious Diseases | 2010
Sasi R. Jonnalagadda; Barbara Lohman Payne; Elizabeth R. Brown; Dalton Wamalwa; Elizabeth Obimbo; Maxwel Majiwa; Carey Farquhar; Phelgona Otieno; Dorothy Mbori-Ngacha; Grace John-Stewart
BACKGROUND We evaluated the prognostic usefulness of interferon γ release assays (IGRAs) for active tuberculosis and mortality in Kenyan human immunodeficiency virus type 1 (HIV-1)-infected women and their infants. METHODS Prevalence and correlates of Mycobacterium tuberculosis-specific T-SPOT.TB IGRA positivity were determined during pregnancy in a historical cohort of HIV-1-infected women. Hazard ratios, adjusted for baseline maternal CD4 cell count (aHR(CD4)), were calculated for associations between IGRA positivity and risk of active tuberculosis and mortality over 2-year postpartum follow-up among women and their infants. RESULTS Of 333 women tested, 52 (15.6%) had indeterminate IGRA results. Of the remaining 281 women, 120 (42.7%) had positive IGRA results, which were associated with a 4.5-fold increased risk of active tuberculosis (aHR(CD4), 4.5; 95% confidence interval [CI], 1.1-18.0; P = .030). For immunosuppressed women (CD4 cell count, <250 cells/μL), positive IGRA results were associated with increased risk of maternal mortality (aHR(CD4), 3.5; 95% CI, 1.02-12.1;), maternal active tuberculosis or mortality (aHR(CD4), 5.2; 95% CI, 1.7-15.6; P = .004), and infant active tuberculosis or mortality overall (aHR(CD4), 3.0; 95% CI, 1.0-8.9; P = .05) and among HIV-1-exposed uninfected infants (aHR(CD4), 7.3; 95% CI, 1.6-33.5; P = .01). CONCLUSIONS Positive IGRA results for HIV-1-infected pregnant women were associated with postpartum active tuberculosis and mortality among mothers and their infants.
PLOS Neglected Tropical Diseases | 2010
Judd L. Walson; Barclay T. Stewart; Laura Sangaré; Loice W. Mbogo; Phelgona Otieno; Benjamin Piper; Barbra A. Richardson; Grace John-Stewart
Background Deworming HIV-1 infected individuals may delay HIV-1 disease progression. It is important to determine the prevalence and correlates of HIV-1/helminth co-infection in helminth-endemic areas. Methods HIV-1 infected individuals (CD4>250 cells/ul) were screened for helminth infection at ten sites in Kenya. Prevalence and correlates of helminth infection were determined. A subset of individuals with soil-transmitted helminth infection was re-evaluated 12 weeks following albendazole therapy. Results Of 1,541 HIV-1 seropositive individuals screened, 298 (19.3%) had detectable helminth infections. Among individuals with helminth infection, hookworm species were the most prevalent (56.3%), followed by Ascaris lumbricoides (17.1%), Trichuris trichiura (8.7%), Schistosoma mansoni (7.1%), and Stongyloides stercoralis (1.3%). Infection with multiple species occurred in 9.4% of infections. After CD4 count was controlled for, rural residence (RR 1.40, 95% CI: 1.08–1.81), having no education (RR 1.57, 95% CI: 1.07–2.30), and higher CD4 count (RR 1.36, 95% CI: 1.07–1.73) remained independently associated with risk of helminth infection. Twelve weeks following treatment with albendazole, 32% of helminth-infected individuals had detectable helminths on examination. Residence, education, and CD4 count were not associated with persistent helminth infection. Conclusions Among HIV-1 seropositive adults with CD4 counts above 250 cells/mm3 in Kenya, traditional risk factors for helminth infection, including rural residence and lack of education, were associated with co-infection, while lower CD4 counts were not. Trial Registration ClinicalTrials.gov NCT00130910
Lancet Infectious Diseases | 2012
Judd L. Walson; Benson Singa; Laura Sangaré; Jaqueline M. Naulikha; Benjamin Piper; Barbra A. Richardson; Phelgona Otieno; Loice W. Mbogo; James A. Berkley; Grace John-Stewart
BACKGROUND Co-infection with HIV and helminths is common in sub-Saharan Africa and findings from previous studies have suggested that anthelmintic treatment might delay immunosuppression in people with HIV. We aimed to assess the efficacy of empiric deworming of adults with HIV in delaying HIV disease progression. METHODS In this non-blinded randomised trial, we enrolled adults (aged ≥18 years) with HIV who did not meet criteria for the initiation of antiretroviral treatment from three sites in Kenya. Using a computer-generated sequence, we randomly assigned (1:1) eligible participants to either empiric albendazole every 3 months plus praziquantel annually (treatment group) or to standard care (control group). Participants were followed up for 24 months. We measured CD4 cell counts every 6 months and plasma HIV RNA annually. The primary endpoints were a CD4 count of less than 350 cells per μL and a composite endpoint consisting of the first occurrence of a CD4 count of less than 350 cells per μL, first reported use of antiretroviral treatment, and non-traumatic deaths. We compared these measures by use of Cox proportional hazards regression and Kaplan-Meier survival analyses. Primary analysis was done by intention to treat. The trial was registered with ClinicalTrials.gov, number NCT0050722. FINDINGS Between Feb 6, 2008, and June 21, 2011, we enrolled and followed-up 948 participants; 469 were allocated to the treatment group and 479 to the control group. All participants were provided with co-trimoxazole prophylaxis. Median baseline CD4 cell counts and HIV RNA concentrations did not differ between groups. We recorded no statistically significant difference between the treatment and control groups in the number of people reaching a CD4 count of fewer than 350 cells per μL (41·6 events per 100 person-years vs 46·2 events per 100 person-years; hazard ratio 0·89, 95% CI 0·75-1·06, p=0·2) or the composite endpoint (44·0 events per 100 person-years vs 49·8 events per 100 person-years; 0·88, 0·74-1·04, p=0·1). Serious adverse events, none of which thought to be treatment-related, occurred at a similar frequency in both groups. INTERPRETATION Our findings do not suggest an effect of empiric deworming in the delaying of HIV disease progression in adults with HIV in an area where helminth infection is common. Alternative approaches are needed to delay HIV disease progression in areas where co-infections are common.