Browsing by Author "Orang’o, Omenge"
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Item Association of Plasma Aflatoxin With Persistent Detection of Oncogenic Human Papillomaviruses in Cervical Samples From Kenyan Women Enrolled in a Longitudinal Study(BMC, 2023-06-06) Tong, Yan; Tonui, Philip; Orang’o, Omenge; Zhang, Jianjun; Maina, Titus; Muthoka, Kapten; Groopman, John; Smith, Joshua; Madeen, Erin; Ermel, Aaron; Loehrer, Patrick; Brown, Darron R.; Biostatistics, School of Public HealthBackground: Cervical cancer is caused by oncogenic human papillomaviruses (HR-HPV) and is common among Kenyan women. Identification of factors that increase HR-HPV persistence is critically important. Kenyan women exposed to aflatoxin have an increased risk of HR-HPV detection in cervical specimens. This analysis was performed to examine associations between aflatoxin and HR-HPV persistence. Methods: Kenyan women were enrolled in a prospective study. The analytical cohort for this analysis included 67 HIV-uninfected women (mean age 34 years) who completed at least two of three annual study visits and had an available blood sample. Plasma aflatoxin was detected using ultra-high pressure liquid chromatography (UHPLC)-isotope dilution mass spectrometry. Annual cervical swabs were tested for HPV (Roche Linear Array). Ordinal logistic regression models were fitted to examine associations of aflatoxin and HPV persistence. Results: Aflatoxin was detected in 59.7% of women and was associated with higher risk of persistent detection of any HPV type (OR = 3.03, 95%CI = 1.08-8.55, P = 0.036), HR-HPV types (OR = 3.63, 95%CI = 1.30-10.13, P = 0.014), and HR-HPV types not included in the 9-valent HPV vaccine (OR = 4.46, 95%CI = 1.13-17.58, P = 0.032). Conclusions: Aflatoxin detection was associated with increased risk of HR-HPV persistence in Kenyan women. Further studies, including mechanistic studies are needed to determine if aflatoxin synergistically interacts with HR-HPV to increase cervical cancer risk.Item Cervical cancer prevention and care in HIV clinics across sub-Saharan Africa: results of a facility-based survey(Wiley, 2024) Asangbeh-Kerman, Serra Lem; Davidović, Maša; Taghavi, Katayoun; Dhokotera, Tafadzwa; Manasyan, Albert; Sharma, Anjali; Jaquet, Antoine; Musick, Beverly; Twizere, Christella; Chimbetete, Cleophas; Murenzi, Gad; Tweya, Hannock; Muhairwe, Josephine; Wools-Kaloustian, Kara; Technau, Karl-Gunter; Anastos, Kathryn; Yotebieng, Marcel; Jousse, Marielle; Ezechi, Oliver; Orang’o, Omenge; Bosomprah, Samuel; Boni, Simon Pierre; Basu, Partha; Bohlius, Julia; IeDEA; Biostatistics and Health Data Science, Richard M. Fairbanks School of Public HealthIntroduction: To eliminate cervical cancer (CC), access to and quality of prevention and care services must be monitored, particularly for women living with HIV (WLHIV). We assessed implementation practices in HIV clinics across sub-Saharan Africa (SSA) to identify gaps in the care cascade and used aggregated patient data to populate cascades for WLHIV attending HIV clinics. Methods: Our facility-based survey was administered between November 2020 and July 2021 in 30 HIV clinics across SSA that participate in the International epidemiology Databases to Evaluate AIDS (IeDEA) consortium. We performed a qualitative site-level assessment of CC prevention and care services and analysed data from routine care of WLHIV in SSA. Results: Human papillomavirus (HPV) vaccination was offered in 33% of sites. Referral for CC diagnosis (42%) and treatment (70%) was common, but not free at about 50% of sites. Most sites had electronic health information systems (90%), but data to inform indicators to monitor global targets for CC elimination in WLHIV were not routinely collected in these sites. Data were collected routinely in only 36% of sites that offered HPV vaccination, 33% of sites that offered cervical screening and 20% of sites that offered pre-cancer and CC treatment. Conclusions: Though CC prevention and care services have long been available in some HIV clinics across SSA, patient and programme monitoring need to be improved. Countries should consider leveraging their existing health information systems and use monitoring tools provided by the World Health Organization to improve CC prevention programmes and access, and to track their progress towards the goal of eliminating CC.Item A community-based approach to cervical cancer prevention in western Kenya: An AMPATH feasibility project(Sage, 2022-05-23) Orang’o, Omenge; Tonui, Philip; Muthoka, Kapten; Kiptoo, Stephen; Maina, Titus; Agosa, Mercy; Ermel, Aaron; Tong, Yan; Brown, Darron; Medicine, School of MedicineObjectives: Centralized programs have been ineffective in reducing the burden of cervical cancer among Kenyan women. A community-based pilot study was initiated to screen Kenyan women for cervical cancer and to vaccinate their children against human papillomavirus (HPV). Methods: Women were educated about cervical cancer prevention at community meetings. Women then provided self-collected vaginal swabs for oncogenic HPV testing using the Roche Cobas Assay. All women were then referred to the local clinic for Visual Inspection with Acetic Acid (VIA). Women were offered the quadrivalent HPV vaccine for their children if and when it became available for the study. Results: Women in western Kenya were invited to participate in community meetings. A total of 200 women were enrolled: 151 (75.5%) were HIV-uninfected and 49 (24.5%) were HIV-infected; the median age for all women was 42 years. High-risk (HR)-HPV types were detected in 49 of swabs from all 200 participants (24.5%) including 20.5% of HIV-uninfected women and 36.7% of HIV-infected women (P = .022). VIA was performed on 198 women: 192 had normal examinations and six had abnormal examinations. Five cervical biopsies revealed two cases of CIN 2 and one CIN 3. Although all mothers were willing to have their children (N = 432) vaccinated, the HPV vaccine could not be delivered to Kenya during the study period. Conclusions: Kenyan women were willing to attend community meetings to learn about prevention of cervical cancer, to provide self-collected vaginal swabs for HPV testing, to travel to the Webuye Clinic for VIA following the collection of swabs, and to have their children vaccinated against HPV. HR-HPV was prevalent, especially in HIV-infected women. As a result of this pilot study, this community-based strategy to prevent cervical cancer will be continued in western Kenya.Item Detection and Concentration of Plasma Aflatoxin Is Associated With Detection of Oncogenic Human Papillomavirus in Kenyan Women(Oxford Academic, 2019-09-01) Zhang, Jianjun; Orang’o, Omenge; Tonui, Philip; Tong, Yan; Maina, Titus; Kiptoo, Stephen; Muthoka, Katpen; Groopman, John; Smith, Joshua; Madeen, Erin; Ermel, Aaron; Loehrer, Patrick; Brown, Darron R.; Department of Epidemiology, School of Public HealthAbstract Background Cervical cancer is common in Kenyan women. Cofactors in addition to infection with oncogenic human papillomavirus (HPV) are likely to be important in causing cervical cancer, because only a small percentage of HPV-infected women will develop this malignancy. Kenyan women are exposed to dietary aflatoxin, a potent carcinogen and immunosuppressive agent, which may be such a cofactor. Methods Demographics, behavioral data, plasma, and cervical swabs were collected from 88 human immunodeficiency virus-uninfected Kenyan women without cervical dysplasia. Human papillomavirus detection was compared between women with or without plasma aflatoxin B1-lysine (AFB1-lys) and evaluated in relation to AFB1-lys concentration. Results Valid HPV testing results were available for 86 women (mean age 34.0 years); 49 women (57.0%) had AFB1-lys detected and 37 (43.0%) had none. The AFB1-lys detection was not associated with age, being married, having more than secondary school education, home ownership, living at a walking distance to healthcare ≥60 minutes, number of lifetime sex partners, or age of first sex. The AFB1-lys detection and plasma concentrations were associated with detection of oncogenic HPV types. Conclusions The AFB1-lys positivity and higher plasma AFB1-lys concentrations were associated with higher risk of oncogenic HPV detection in cervical samples from Kenya women. Further studies are needed to determine whether aflatoxin interacts with HPV in a synergistic manner to increase the risk of cervical cancer.Item Invasive cervical cancers in the United States, Botswana and Kenya: HPV type distribution and health policy implications(BioMed Central, 2016) Ermel, Aaron; Qadadri, Brahim; Tong, Yan; Orang’o, Omenge; Macharia, Benson; Ramogola-Masire, Doreen; Zetola, Nicola M.; Brown, Darron R.; Department of Medicine, School of MedicineBackground More deaths occur in African women from invasive cervical cancer (ICC) than from any other malignancy. ICC is caused by infection with oncogenic types of human papillomavirus (HPV). Co-infection with the human immunodeficiency virus (HIV) accelerates the natural history of ICC, and may influence the HPV type distribution. Because HPV vaccines are available, this malignancy is theoretically preventable, but the vaccines are largely type-specific in protection against infection. Data on specific HPV types causing ICC in African women is limited, and many studies utilized swab samples rather than actual cancer tissue. A previous study using archived, ICC tissue from women in Botswana identified an unusual HPV type distribution. A similar study was therefore performed in a second sub-Saharan country to provide additional information on the HPV type distribution in ICC. Methods Archived, formalin-fixed, paraffin-embedded ICCs were acquired from women in the United States, Kenya, or Botswana. DNA was extracted and HPV genotyping performed by Roche Linear Array. HIV sequences were identified in ICCs by PCR. Results HPV types 16 or 18 (HPV 16/18) were identified in 93.5 % of HPV-positive ICCs from the U.S., 93.8 % from Kenya, and 61.8 % from Botswana (p < 0.0001). Non-HPV 16/18 types were detected in 10.9 % of HPV-positive cancers from the U.S., 17.2 % from Kenya, and 47.8 % from Botswana (p < 0.0001). HIV was detected in 2.2, 31.5, and 32.4 % from ICCs from the U.S., Kenya, or Botswana, respectively (p = 0.0002). The distribution of HPV types was not significantly different between HIVinfected or HIV-uninfected women. The percentages of ICCs theoretically covered by the bivalent/quadrivalent HPV vaccines were 93.5, 93.9, and 61.8 % from the U.S., Kenya and Botswana, respectively, and increased to 100, 98, and 77.8 % for the nanovalent vaccine. Conclusions HPV 16/18 caused most ICCs from the U.S. and western Kenya. Fewer ICCs contained HPV 16/18 in Botswana. HIV co-infection did not influence the HPV type distribution in ICCs from African women from the two countries. Available HPV vaccines should provide protection against most ICCs in the U.S. and Kenya. The recently developed nanovalent vaccine may be more suitable for countries where non-HPV 16/18 types are frequently detected in ICC.Item Persistence of oncogenic and non-oncogenic human papillomavirus is associated with human immunodeficiency virus infection in Kenyan women(SAGE, 2020-07-28) Tong, Yan; Tonui, Philip; Ermel, Aaron; Orang’o, Omenge; Wong, Nelson; Titus, Maina; Kiptoo, Stephen; Muthoka, Kapten; Loehrer, Patrick J; Brown, Darron R; Medicine, School of MedicineObjectives: Cervical cancer is caused by persistent infection with oncogenic, or “high-risk” types of human papillomaviruses, and is the most common malignancy in Kenyan women. A longitudinal study was initiated to investigate factors associated with persistent human papillomavirus detection among HIV-infected and HIV-uninfected Kenyan women without evidence of cervical dysplasia. Methods: Demographic/behavioral data and cervical swabs were collected from HIV-uninfected women (n = 82) and HIV-infected women (n = 101) at enrollment and annually for 2 years. Human papillomavirus typing was performed on swabs (Roche Linear Array). Logistic regression models of human papillomavirus persistence were adjusted for demographic and behavioral characteristics. Results: HIV-infected women were older and less likely to be married and to own a home and had more lifetime sexual partners than HIV-uninfected women. All HIV-infected women were receiving anti-retroviral therapy at enrollment and had satisfactory CD4 cell counts and HIV viral loads. One- and two-year persistent human papillomavirus detection was significantly associated with HIV infection for any human papillomavirus, high-risk human papillomavirus, International Agency for the Research on Cancer-classified high-risk human papillomavirus, and non-oncogenic “low-risk” human papillomavirus. Conclusion: Persistent detection of oncogenic and non-oncogenic human papillomavirus was strongly associated with HIV infection in Kenyan women with re-constituted immune systems based on satisfactory CD4 cell counts. In addition to HIV infection, factors associated with an increased risk of human papillomavirus persistence included a higher number of lifetime sex partners. Factors associated with decreased risk of human papillomavirus persistence included older age and being married. Further studies are needed to identify the immunological defects in HIV-infected women that allow human papillomavirus persistence, even in women receiving effective anti-retroviral therapy. Further studies are also needed to determine the significance of low-risk human papillomavirus persistence in HIV-infected women.Item Real-World Cervical Cancer Screening Uptake and Predictors of Visual Inspection With Acetic Acid Positivity Among Women Living With HIV in Care Programs in Western Kenya(American Society of Clinical Oncology, 2024) Mungo, Chemtai; Orang’o, Omenge; Ofner, Susan; Musick, Beverly; Yiannoutsos, Constantin; Cohen, Craig R.; Brown, Darron; Wools-Kaloustian, Kara; Semeere, Aggrey; Biostatistics and Health Data Science, Richard M. Fairbanks School of Public HealthPurpose: To achieve the WHO cervical cancer elimination targets, countries globally must achieve 70% cervical cancer screening (CCS) coverage. We evaluated CCS uptake and predictors of screening positive at two public HIV care programs in western Kenya. Methods: From October 2007 to February 2019, data from the Family AIDS Care and Education Services (FACES) and Academic Model Providing Access to Healthcare (AMPATH) programs in western Kenya were analyzed. The study population included women age 18-65 years enrolled in HIV care. Screening uptake was calculated annually and overall, determining the proportion of eligible women screened. Multivariate logistic regression assessed predictors of positive screening outcomes. Results: There were 57,298 women living with HIV (WLWHIV) eligible for CCS across both programs during the study period. The mean age was 31.4 years (IQR, 25.9-37.8), and 39% were on antiretroviral therapy (ART) at the first CCS-eligible visit. Of all eligible women, 29.4% (95% CI, 29.1 to 29.8) underwent CCS during the study period, 27.0% (95% CI, 26.5 to 27.4) in the AMPATH program, and 35.6% (95% CI, 34.9 to 36.4) in the FACES program. Annual screening uptake varied greatly in both programs, with coverage as low as 1% of eligible WLWHIV during specific years. Age at first screening, CD4 count within 90 days of screening, current use of ART, and program (AMPATH v FACES) were each statistically significant predictors of positive screening. Conclusion: CCS uptake at two large HIV care programs in Kenya fell short of the WHO's 70% screening target. Screening rates varied significantly on the basis of the availability of funding specific to CCS, reflecting the limitations of vertical funding programs.