Anthony Gichangi
Centers for Disease Control and Prevention
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BMC Infectious Diseases | 2012
Jamal Ahmed; Mark A. Katz; Eric Auko; M. Kariuki Njenga; Michelle Weinberg; Bryan K. Kapella; Heather Burke; Raymond Nyoka; Anthony Gichangi; Lilian W. Waiboci; Abdirahman Mahamud; Mohamed Qassim; Babu Swai; Burton Wagacha; David Mutonga; Margaret Nguhi; Robert F. Breiman; Rachel B. Eidex
BackgroundRefugees are at risk for poor outcomes from acute respiratory infections (ARI) because of overcrowding, suboptimal living conditions, and malnutrition. We implemented surveillance for respiratory viruses in Dadaab and Kakuma refugee camps in Kenya to characterize their role in the epidemiology of ARI among refugees.MethodsFrom 1 September 2007 through 31 August 2010, we obtained nasopharyngeal (NP) and oropharyngeal (OP) specimens from patients with influenza-like illness (ILI) or severe acute respiratory infections (SARI) and tested them by RT-PCR for adenovirus (AdV), respiratory syncytial virus (RSV), human metapneumovirus (hMPV), parainfluenza viruses (PIV), and influenza A and B viruses. Definitions for ILI and SARI were adapted from those of the World Health Organization. Proportions of cases associated with viral aetiology were calculated by camp and by clinical case definition. In addition, for children < 5 years only, crude estimates of rates due to SARI per 1000 were obtained.ResultsWe tested specimens from 1815 ILI and 4449 SARI patients (median age = 1 year). Proportion positive for virus were AdV, 21.7%; RSV, 12.5%; hMPV, 5.7%; PIV, 9.4%; influenza A, 9.7%; and influenza B, 2.6%; 49.8% were positive for at least one virus. The annual rate of SARI hospitalisation for 2007-2010 was 57 per 1000 children per year. Virus-positive hospitalisation rates were 14 for AdV; 9 for RSV; 6 for PIV; 4 for hMPV; 5 for influenza A; and 1 for influenza B. The rate of SARI hospitalisation was highest in children < 1 year old (156 per 1000 child-years). The ratio of rates for children < 1 year and 1 to < 5 years old was 3.7:1 for AdV, 5.5:1 for RSV, 4.4:1 for PIV, 5.1:1 for hMPV, 3.2:1 for influenza A, and 2.2:1 for influenza B. While SARI hospitalisation rates peaked from November to February in Dadaab, no distinct seasonality was observed in Kakuma.ConclusionsRespiratory viral infections, particularly RSV and AdV, were associated with high rates of illness and make up a substantial portion of respiratory infection in these two refugee settings.
PLOS ONE | 2011
Clement Zeh; Pauli N. Amornkul; Seth Inzaule; Pascale Ondoa; Boaz Oyaro; Dufton Mwaengo; Hilde Vandenhoudt; Anthony Gichangi; John Williamson; Timothy K. Thomas; Kevin M. DeCock; Clyde E. Hart; John N. Nkengasong; Kayla F. Laserson
Background There is need for locally-derived age-specific clinical laboratory reference ranges of healthy Africans in sub-Saharan Africa. Reference values from North American and European populations are being used for African subjects despite previous studies showing significant differences. Our aim was to establish clinical laboratory reference values for African adolescents and young adults that can be used in clinical trials and for patient management. Methods and Findings A panel of 298, HIV-seronegative individuals aged 13–34 years was randomly selected from participants in two population-based cross-sectional surveys assessing HIV prevalence and other sexually transmitted infections in western Kenya. The adolescent (<18 years)-to-adults (≥18 years) ratio and the male-to-female ratio was 1∶1. Median and 95% reference ranges were calculated for immunohematological and biochemistry values. Compared with U.S-derived reference ranges, we detected lower hemoglobin (HB), hematocrit (HCT), red blood cells (RBC), mean corpuscular volume (MCV), neutrophil, glucose, and blood urea nitrogen values but elevated eosinophil and total bilirubin values. Significant gender variation was observed in hematological parameters in addition to T-bilirubin and creatinine indices in all age groups, AST in the younger and neutrophil, platelet and CD4 indices among the older age group. Age variation was also observed, mainly in hematological parameters among males. Applying U.S. NIH Division of AIDS (DAIDS) toxicity grading to our results, 40% of otherwise healthy study participants were classified as having an abnormal laboratory parameter (grade 1–4) which would exclude them from participating in clinical trials. Conclusion Hematological and biochemistry reference values from African population differ from those derived from a North American population, showing the need to develop region-specific reference values. Our data also show variations in hematological indices between adolescent and adult males which should be considered when developing reference ranges. This study provides the first locally-derived clinical laboratory reference ranges for adolescents and young adults in western Kenya.
The Open Aids Journal | 2011
Tom Oluoch; Ibrahim Mohammed; Rebecca Bunnell; Reinhard Kaiser; Andrea A. Kim; Anthony Gichangi; Mary Mwangi; Sufia Dadabhai; Lawrence H. Marum; Alloys Orago; Jonathan Mermin
Objective: To identify factors associated with prevalent HIV in a national HIV survey in Kenya. Methods: The Kenya AIDS Indicator Survey was a nationally representative population-based sero-survey that examined demographic and behavioral factors and serologic testing for HIV, HSV-2 and syphilis in adults aged 15-64 years. We analyzed questionnaire and blood testing data to identify significant correlates of HIV infection among sexually active adults. Results: Of 10,957 eligible women and 8,883 men, we interviewed 10,239 (93%) women and 7,731 (87%) men. We collected blood specimens from 9,049 women and 6,804 men of which 6,447 women and 5,112 men were sexually active during the 12 months prior to the survey. HIV prevalence among sexually active adults was 7.4%. Factors independently associated with HIV among women were region (Nyanza vs Nairobi: adjusted OR [AOR] 1.6, 95%CI 1.1-2.3), number of lifetime sex partners (6-9 vs 0-1 partners: AOR 3.0, 95%CI 1.6-5.9), HSV-2 (AOR 6.5, 95%CI 4.9-8.8), marital status (widowed vs never married: AOR 2.7, 95%CI 1.5-4.8) and consistent condom use with last sex partner (AOR 2.3, 95%CI 1.6-3.4). Among men, correlates of HIV infection were 30-to-39-year-old age group (AOR 5.2, 95%CI 2.6-10.5), number of lifetime sex partners (10+ vs 0-1 partners, AOR 3.5, 95%CI 1.4-9.0), HSV-2 (AOR 4.7, 95%CI 3.2-6.8), syphilis (AOR 2.4, 95%CI 1.4-4.0), consistent condom use with last sex partner (AOR 2.1, 95% CI 1.5-3.1) and lack of circumcision (AOR 4.0, 95%CI 2.8 - 5.5). Conclusion: Kenya’s heterogeneous epidemic will require regional and gender-specific prevention approaches.
Vox Sanguinis | 2011
D. Kimani; Jane Mwangi; Mary Mwangi; Rebecca Bunnell; T. A. Kellogg; Tom Oluoch; Anthony Gichangi; Reinhard Kaiser; N. Mugo; T. Odongo; Margaret Oduor; Lawrence H. Marum
Background and Objectives Blood safety and sufficiency are major challenges in Kenya and other sub‐Saharan African countries forcing many countries to rely on family replacement donors (FRD). We analysed data from a national AIDS indicator survey to describe blood donors in Kenya and potential risks of transfusion transmissible infections (TTI) comparing voluntary donors and FRD.
Journal of Acquired Immune Deficiency Syndromes | 2014
Rose Wafula; Sarah Masyuko; Lucy Ng’ang’a; Andrea A. Kim; Anthony Gichangi; Irene Mukui; James Batuka; Evelyn W. Ngugi; William K. Maina; Sandra Schwarcz
Background:Increasing access to care and treatment for HIV-infected persons is a goal in Kenyas response to the HIV epidemic. Using data from the second Kenya AIDS Indicator Survey (KAIS 2012), we describe coverage of services received among adults and adolescents who were enrolled in HIV care. Methods:KAIS 2012 was a population-based survey that collected information from persons aged 15–64 years that included self-reported HIV status, and for persons reporting HIV infection, use of HIV care and antiretroviral therapy (ART). Blood specimens were collected and tested for HIV. HIV-positive specimens were tested for CD4 counts and viral load. Results:Among 363 persons who reported HIV infection, 93.4% [95% confidence interval (CI): 87.2 to 99.6] had ever received HIV care. Among those receiving HIV care, 96.3% (95% CI: 94.1 to 98.4) were using cotrimoxazole prophylaxis, and 74.6% (95% CI: 69.0 to 80.2) were receiving ART. A lower proportion of persons in care and not on ART reported using cotrimoxazole (89.5%, 95% CI: 82.5 to 96.5 compared with 98.6%, 95% CI: 97.1 to 100) and had a CD4 count measurement done (72.9%, 95% CI: 64.0 to 81.9 compared with 90.0%, 95% CI: 82.8 to 97.3) than persons in care and on ART, respectively. Among persons in care and not on ART, 23.2% (95% CI: 6.8 to 39.7) had CD4 counts ⩽350 cells per microliter. Viral suppression was observed in 75.3% (95% CI: 68.7 to 81.9) of persons on ART. Conclusions:Linkage and retention in care are high among persons with known HIV infection. However, improvements in care for the pre-ART population are needed. Viral suppression rates were comparable to developed settings.
Journal of Acquired Immune Deficiency Syndromes | 2011
Mary Mwangi; Rebecca Bunnell; Raymond Nyoka; Anthony Gichangi; Ernest Makokha; Andrea A. Kim; George Kichamu; Lawrence H. Marum; Jared Ichwara; Jonathan Mermin
Objective:Assess factors associated with knowledge of HIV status, sexual activity, and unprotected sex with a partner of unknown or negative HIV status (unsafe sex) among HIV-infected adults in Kenya. Design:Nationally representative Kenya AIDS Indicator Survey among adults aged 15-64 years in 2007. Methods:A standardized questionnaire was administered and blood samples tested for HIV. We assessed factors associated with knowledge of HIV infection, sexual activity, and unsafe sex. Analyses took into account stratification and clustering in the survey design and estimates were weighted to account for sampling probability. Results:Of 15,853 participants with blood samples, 1104 (6.9%) were HIV infected. Of these, 83.8% did not know their HIV status (56% had never tested; 27.8% reported their last HIV test was negative), and 80.4% were sexually active. Of 861 sexually active adults, 76.9% reported unsafe sex in the past year. Adults who did not know their HIV status were more likely to be sexually active [never tested adjusted odds ratio (AOR): 5.5, 95% confidence interval (CI): 2.8 to 10.7; ever tested, incorrect knowledge AOR: 6.5, CI: 2.1 to 19.6) and to report unsafe sex (never tested AOR: 51.7, CI: 27.3 to 97.6; ever tested, incorrect knowledge of status AOR: 18.6, CI: 8.6 to 40.5) than those who knew their status. Conclusions:The majority of adults did not know they were infected and engaged in unsafe sex. Adults who knew their HIV status were less likely to be sexually active and report unsafe sex compared with those unaware of their infection. HIV prevention interventions that target HIV-infected adults are urgently needed.
Bulletin of The World Health Organization | 2012
Zebedee Mwandi; Rebecca Bunnell; Peter Cherutich; Jonathan Mermin; Andrea A. Kim; Anthony Gichangi; Patrick Mureithi; Timothy A. Kellogg; Tom Oluoch; James Muttunga; Carol Ngare; Evelyn Kim; Reinhard Kaiser
OBJECTIVE To provide guidance for male circumcision programmes in Kenya by estimating the population of uncircumcised men and investigating the association between circumcision and infection with the human immunodeficiency virus (HIV), with particular reference to uncircumcised, HIV-uninfected men. METHODS Data on men aged 15 to 64 years were derived from the 2007 Kenya AIDS Indicator Survey, which involved interviews and blood collection to test for HIV and herpes simplex virus 2 (HSV-2). The prevalence of HIV infection and circumcision in Kenyan provinces was calculated and the demographic characteristics and sexual behaviour of circumcised and uncircumcised, HIV-infected and HIV-uninfected men were recorded. FINDINGS The national prevalence of HIV infection in uncircumcised men was 13.2% (95% confidence interval, CI: 10.8-15.7) compared with 3.9% (95% CI: 3.3-4.5) among circumcised men. Nyanza province had the largest estimated number of uncircumcised, HIV-uninfected men (i.e. 601 709), followed by Rift Valley, Nairobi and Western Province, respectively, and most belonged to the Luo ethnic tribe. Of these men, 77.8% did not know their HIV status and 33.2% were HSV-2-positive. In addition, 65.3% had had unprotected sex with a partner of discordant or unknown HIV status in the past 12 months and only 14.7% consistently used condoms with their most recent partner. However, only 21.8% of the uncircumcised, HIV-uninfected men aged 15 to 19 years were sexually active. CONCLUSION The Kenyan male circumcision strategy should focus on the provinces with the highest number of uncircumcised, HIV-uninfected men and target young men before or shortly after sexual debut.
Journal of Acquired Immune Deficiency Syndromes | 2014
Agneta Mbithi; Anthony Gichangi; Andrea A. Kim; Abraham Katana; Herman Weyenga; John Williamson; Katherine Robinson; Tom Oluoch; William K. Maina; Timothy A. Kellogg; Kevin M. De Cock
Background:Co-morbidity with tuberculosis and HIV is a common cause of mortality in sub-Saharan Africa. In the second Kenya AIDS Indicator Survey, we collected data on knowledge and experience of HIV and tuberculosis, as well as on access to and coverage of relevant treatment services and antiretroviral therapy (ART) in Kenya. Methods:A national, population-based household survey was conducted from October 2012 to February 2013. Information was collected through household questionnaires, and blood samples were taken for HIV, CD4 cell counts, and HIV viral load testing at a central laboratory. Results:Overall, 13,720 persons aged 15–64 years participated; 96.7% [95% confidence interval (CI): 96.3 to 97.1] had heard of tuberculosis, of whom 2.0% (95% CI: 1.7 to 2.2) reported having prior tuberculosis. Among those with laboratory-confirmed HIV infection, 11.6% (95% CI: 8.9 to 14.3) reported prior tuberculosis. The prevalence of laboratory-confirmed HIV infection in persons reporting prior tuberculosis was 33.2% (95% CI: 26.2 to 40.2) compared to 5.1% (95% CI: 4.5 to 5.8) in persons without prior tuberculosis. Among those in care, coverage of ART for treatment-eligible persons was 100% for those with prior tuberculosis and 88.6% (95% CI: 81.6 to 95.7) for those without. Among all HIV-infected persons, ART coverage among treatment-eligible persons was 86.9% (95% CI: 74.2 to 99.5) for persons with prior tuberculosis and 58.3% (95% CI: 47.6 to 69.0) for those without. Conclusions:Morbidity from tuberculosis and HIV remain major health challenges in Kenya. Tuberculosis is an important entry point for HIV diagnosis and treatment. Lack of knowledge of HIV serostatus is an obstacle to access to HIV services and timely ART for prevention of HIV transmission and HIV-associated disease, including tuberculosis.
Journal of Adolescent Health | 2018
Bernadette Ngeno; Anthony Waruru; Irene Inwani; Lucy Nganga; Evelyn Ngugi Wangari; Abraham Katana; Anthony Gichangi; Ann Mwangi; Irene Mukui; George W. Rutherford
PURPOSE Informing adolescents of their own HIV infection is critical as the number of adolescents living with HIV increases. We assessed the association between HIV disclosure and retention in care and mortality among adolescents aged 10-14 years in Kenyas national program. METHODS We abstracted routinely collected patient-level data for adolescents enrolled into HIV care in 50 health facilities from November 1, 2004, through March 31, 2010. We defined disclosure as any documentation that the adolescent had been fully or partially made aware of his or her HIV status. We compared weighted proportions for categorical variables using χ2 and weighted logistic regression to identify predictors of HIV disclosure; we estimated the probability of LTFU using Kaplan-Meier methods and dying using Cox regression-based test for equality of survival curves. RESULTS Of the 710 adolescents aged 10-14 years analyzed; 51.3% had severe immunosuppression, 60.3% were in WHO stage 3 or 4, and 36.6% were aware of their HIV status. Adolescents with HIV-infected parents, histories of opportunistic infections (OIs), and enrolled in support groups were more likely to be disclosed to. At 36 months, disclosure was associated with lower mortality [1.5% (95% CI .6%-4.1%) versus 5.4% (95% CI 3.6.6%-8.0%, p < .001)] and lower LTFU [6.2% (95% CI 3.0%-12.6%) versus 33.9% (95% CI 27.3%-41.1%) p < .001]. CONCLUSIONS Only one third of HIV-infected Kenyan adolescents in treatment programs had been told they were infected, and knowing their HIV status was associated with reduced LTFU and mortality. The disclosure process should be systematically encouraged and organized for HIV-infected adolescents.
PLOS ONE | 2017
Raymond Nyoka; Jimmy Omony; Samuel M. Mwalili; Thomas N. O. Achia; Anthony Gichangi; Henry Mwambi
Respiratory syncytial virus (RSV) is one of the major causes of acute lower respiratory tract infections (ALRTI) in children. Children younger than 1 year are the most susceptible to RSV infection. RSV infections occur seasonally in temperate climate regions. Based on RSV surveillance and climatic data, we developed statistical models that were assessed and compared to predict the relationship between weather and RSV incidence among refugee children younger than 5 years in Dadaab refugee camp in Kenya. Most time-series analyses rely on the assumption of Gaussian-distributed data. However, surveillance data often do not have a Gaussian distribution. We used a generalized linear model (GLM) with a sinusoidal component over time to account for seasonal variation and extended it to a generalized additive model (GAM) with smoothing cubic splines. Climatic factors were included as covariates in the models before and after timescale decompositions, and the results were compared. Models with decomposed covariates fit RSV incidence data better than those without. The Poisson GAM with decomposed covariates of climatic factors fit the data well and had a higher explanatory and predictive power than GLM. The best model predicted the relationship between atmospheric conditions and RSV infection incidence among children younger than 5 years. This knowledge helps public health officials to prepare for, and respond more effectively to increasing RSV incidence in low-resource regions or communities.