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1.
J Acquir Immune Defic Syndr ; 95(2): 170-178, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38211958

RESUMO

BACKGROUND: Of women with cervical cancer (CC) and HIV, 85% live in sub-Saharan Africa, where 21% of all CC cases are attributable to HIV infection. We aimed to generate internationally acceptable facility-based indicators to monitor and guide scale up of CC prevention and care services offered on-site or off-site by HIV clinics. METHODS: We reviewed the literature and extracted relevant indicators, grouping them into domains along the CC control continuum. From February 2021 to March 2022, we conducted a three-round, online Delphi process to reach consensus on indicators. We invited 106 experts to participate. Through an anonymous, iterative process, participants adapted the indicators to their context (round 1), then rated them for 5 criteria on a 5-point Likert-type scale (rounds 2 and 3) and then ranked their importance (round 3). RESULTS: We reviewed 39 policies from 21 African countries and 7 from international organizations; 72 experts from 15 sub-Saharan Africa countries or international organizations participated in our Delphi process. Response rates were 34% in round 1, 40% in round 2, and 44% in round 3. Experts reached consensus for 17 indicators in the following domains: primary prevention (human papillomavirus prevention, n = 2), secondary prevention (screening, triage, treatment of precancerous lesions, n = 11), tertiary prevention (CC diagnosis and care, n = 2), and long-term impact of the program and linkage to HIV service (n = 2). CONCLUSION: We recommend that HIV clinics that offer CC control services in sub-Saharan Africa implement the 17 indicators stepwise and adapt them to context to improve monitoring along the CC control cascade.


Assuntos
Infecções por HIV , Neoplasias do Colo do Útero , Humanos , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controle , Consenso , Técnica Delphi , África Subsaariana/epidemiologia
2.
EClinicalMedicine ; 54: 101754, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36583170

RESUMO

Background: In 2020, the World Health Organization (WHO) launched its initiative to eliminate cervical cancer as a public health problem. To inform global efforts for countries with high HIV and cervical cancer burden, we assessed the impact of human papillomavirus (HPV) vaccination and cervical cancer screening and treatment in South Africa, on cervical cancer and the potential for achieving elimination before 2120, considering faster HPV disease progression and higher cervical cancer risk among women living with HIV(WLHIV) and HIV interventions. Methods: Three independent transmission-dynamic models simulating HIV and HPV infections and disease progression were used to predict the impact on cervical cancer incidence of three scenarios for all women: 1) girls' vaccination (9-14 years old), 2) girls' vaccination plus 1 lifetime cervical screen (at 35 years), and 3) girls' vaccination plus 2 lifetime cervical screens (at 35 and 45 years) and three enhanced scenarios for WLHIV: 4) vaccination of young WLHIV aged 15-24 years, 5) three-yearly cervical screening of WLHIV aged 15-49 years, or 6) both. Vaccination assumed 90% coverage and 100% lifetime protection with the nonavalent vaccine (against HPV-16/18/31/33/45/52/58). Cervical cancer screening assumed HPV testing with uptake increasing from 45% (2023), 70% (2030) to 90% (2045+). We also assumed that UNAIDS 90-90-90 HIV treatment and 70% male circumcision targets are reached by 2030. We examined three elimination thresholds: age-standardised cervical cancer incidence rates below 4 or 10 per 100,000 women-years, and >85% reduction in cervical cancer incidence rate. We conducted sensitivity analyses and presented the median age-standardised predictions of outcomes of the three models (minimum-maximum across models). Findings: Girls' vaccination could reduce age-standardised cervical cancer incidence from a median of 47.6 (40.9-79.2) in 2020 to 4.5 (3.2-6.3) per 100,000 women-years by 2120, averting on average ∼4% and ∼46% of age-standardised cumulative cervical cancer cases over 25 and 100 years, respectively, compared to the basecase. Adding 2 lifetime screens helped achieve elimination over the century among all women (2120 cervical cancer incidence: 3.6 (1.9-3.6) per 100,000 women-years), but not among WLHIV (10.8 (5.3-11.6)), and averted more cumulative cancer cases overall (∼45% over 25 years and ∼61% over 100 years compared to basecase) than girls' vaccination alone. Adding three-yearly cervical screening among WLHIV (to girls' vaccination and 2 lifetime cervical screens) further reduced age-standardised cervical cancer incidence to 3.3 (1.8-3.6) per 100,000 women-years overall and to 5.2 (3.9-8.5) among WLHIV by 2120 and averted on average 12-13% additional cumulative cancer cases among all women and 21-24% among WLHIV than girls' vaccination and 2 lifetime cervical screens over 25 years or longer. Long-term vaccine protection and using the nonavalent vaccine was required for elimination. Interpretation: High HPV vaccination coverage of girls and 2 lifetime cervical screens could eliminate cervical cancer among women overall in South Africa by the end of the century and substantially decrease cases among all women and WLHIV over the short and medium term. Cervical cancer elimination in WLHIV would likely require enhanced prevention strategies for WLHIV. Screening of WLHIV remains an important strategy to reduce incidence and alleviate disparities in cervical cancer burden between women with and without HIV, despite HIV interventions scale-up. Funding: World Health Organization. National Cancer Institute, National Institutes of Health. MRC Centre for Global Infectious Disease Analysis, UK Medical Research Council. National Institute of Child Health and Human Development research. Cancer Association of South Africa. Canadian Institutes of Health Research and the Fonds de recherche du Québec - Santé research.

3.
Int J Cancer ; 149(8): 1564-1575, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34164807

RESUMO

In 2020, the World Health Organisation (WHO) published a strategy to eliminate cervical cancer as a public health concern. In South Africa, despite having a national screening policy in place since 2000, diagnosed cervical cancer incidence has shown no signs of decline. We extend a previously developed individual-based model for human immunodeficiency virus (HIV) and human papillomavirus (HPV) infection to include progression to cervical cancer. The model accounts for future reductions in HIV incidence and prevalence and includes a detailed cervical cancer screening algorithm, based on individual-level data from the public health sector. We estimate the impact of the current prevention programme and alternative screening scenarios on cervical cancer incidence. The South African screening programme prevented 8600 (95%CI 4700-12 300) cervical cancer cases between 2000 and 2019. At current levels of prevention (status quo vaccination, screening, and treatment), age-standardised cervical cancer incidence will reduce from 49.4 per 100 000 women (95%CI 36.6-67.2) in 2020, to 12.0 per 100 000 women (95%CI 8.0-17.2) in 2120. Reaching WHO's prevention targets by 2030 could help South Africa reach elimination (at the 10/100 000 threshold) by 2077 (94% probability of elimination by 2120). Using new screening technologies could reduce incidence to 4.7 per 100 000 women (95%CI 2.8-6.7) in 2120 (44% probability of elimination at the 4/100 000 threshold). HPV vaccination and decreasing HIV prevalence will substantially reduce cervical cancer incidence in the long term, but improvements to South Africa's current screening strategy will be required to prevent cases in the short term. Switching to new screening technologies will have the greatest impact.


Assuntos
Alphapapillomavirus/efeitos dos fármacos , Infecções por HIV/prevenção & controle , HIV/efeitos dos fármacos , Modelos Estatísticos , Infecções por Papillomavirus/prevenção & controle , Neoplasias do Colo do Útero/epidemiologia , Vacinas contra a AIDS/administração & dosagem , Adulto , Idoso , Alphapapillomavirus/isolamento & purificação , Detecção Precoce de Câncer/métodos , Feminino , Seguimentos , HIV/isolamento & purificação , Infecções por HIV/complicações , Infecções por HIV/virologia , Humanos , Incidência , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Vacinas contra Papillomavirus/administração & dosagem , Prognóstico , África do Sul/epidemiologia , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/virologia , Adulto Jovem
4.
Vaccine ; 37(36): 5460-5465, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31331772

RESUMO

Mathematical models have been used to estimate the impact of human papillomavirus (HPV) vaccines on infection burden and cervical cancer. Models assume different mechanisms of naturally acquired immunity against re-infection, but processes of latency and reactivation of latent infection have not been explored. This study uses an individual-based dynamic model to simulate randomised controlled trials (RCTs) for vaccine efficacy, using different assumptions about naturally acquired immunity and viral latency after clearance of HPV infection. Model estimates of vaccine effectiveness are compared to those from published RCTs. We then estimate the impact of the bivalent vaccine on HPV-16 and -18 infection burden in South Africa under these different assumptions. When assuming no latency, simulated vaccine effectiveness overestimates results from RCTs and the model cannot match the observed difference in vaccine effectiveness between total vaccinated cohorts and more HPV-naïve cohorts. The reduction in HPV-16 and -18 burden by 2045, following roll-out of vaccination in 2014, does not depend on assumptions about natural immunity, but models that assume no latency predict ∼25% greater reduction in HPV-16 and -18 burden than models that include reactivation of latent infection for all men and women. Mathematical models that do not allow for reactivation of latent HPV infections may therefore overestimate the long-term impact of HPV vaccines.


Assuntos
Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/uso terapêutico , Adolescente , Adulto , Feminino , Papillomavirus Humano 16/imunologia , Papillomavirus Humano 16/patogenicidade , Papillomavirus Humano 18/imunologia , Papillomavirus Humano 18/patogenicidade , Humanos , Masculino , Infecções por Papillomavirus/virologia , Vacinação/métodos , Adulto Jovem
5.
AIDS Res Hum Retroviruses ; 35(7): 615-627, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30938164

RESUMO

Biomarkers for detecting early HIV infection and estimating HIV incidence should minimize false-recent rates (FRRs) while maximizing mean duration of recent infection (MDRI). We compared HIV subtypes B, E and D (BED) capture enzyme immunoassay (BED), Sedia limiting antigen (LAg) avidity enzyme immunoassay, and Bio-Rad avidity incidence (BRAI) assays using samples from Zimbabwean postpartum women infected with clade C HIV. We calculated MDRIs using 590 samples from 351 seroconverting postpartum women, and FRRs using samples from 2,825 women known to be HIV positive for >12 months. Antibody kinetics were more predictable with LAg and had higher precision compared with BED or BRAI. BRAI also exhibited more variability, and avidity reversal in some cases. For BED, LAg, and BRAI, used alone or with viral load, MDRI values in days were: BED-188 and 170 at normalized optical density (ODn) 0.8; LAg-104 and 100 at ODn cutoff 1.5; BRAI-135 and 134 at avidity index cutoff 30%. Corresponding FRRs were: BRAI 1.1% and 1.0% and LAg 0.57% and 0.35%: these were 3.8-10.9 times lower than BED values of 4.8% and 3.8%. BRAI and LAg have significantly lower FRRs and MDRIs than in published studies, and much lower than BED and could be used to estimate incidence in perinatal women and to measure population-level HIV incidence in HIV control operations in Africa.


Assuntos
Sorodiagnóstico da AIDS/métodos , Infecções por HIV/diagnóstico , HIV-1/isolamento & purificação , Técnicas Imunoenzimáticas/métodos , África/epidemiologia , Afinidade de Anticorpos , Biomarcadores/sangue , Contagem de Linfócito CD4 , Estudos de Coortes , Feminino , Anticorpos Anti-HIV/sangue , Anticorpos Anti-HIV/imunologia , Infecções por HIV/epidemiologia , Soropositividade para HIV/diagnóstico , HIV-1/classificação , HIV-1/imunologia , Humanos , Incidência , Período Pós-Parto , Carga Viral
6.
Sex Transm Infect ; 95(2): 122-128, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30171173

RESUMO

OBJECTIVES: Cohort studies have shown significant increased risk of HIV acquisition following human papillomavirus (HPV) detection and increased risk of new HPV detection in individuals with HIV infection, after adjusting for behavioural risk factors. This study uses an individual-based model to assess whether confounding sexual behaviour factors and network level effects can explain these associations between HIV and HPV infection status, without biological interactions. METHODS: The model simulates infection with 13 oncogenic HPV types and HIV. It allows for different relationship types, with heterogeneity in probabilities of concurrency and rates of partner change. No effect of prevalent HPV infection on HIV acquisition is assumed and vice versa. The model is calibrated to South African HIV and type-specific HPV prevalence data using a Bayesian approach. The model is used to simulate cohorts with quarterly HIV and HPV testing from 2000 to 2002. These simulated data are analysed using proportional hazard models. RESULTS: The mean of the unadjusted HRs of HIV acquisition following detection of an oncogenic HPV type calculated for each simulated cohort is 2.6 (95% CI 2.2 to 3.1). The mean of the unadjusted HRs for the effect of HIV on newly detected HPV is 2.5 (95% CI 2.2 to 2.8). Simulated associations between HIV and HPV infection status are similar to corresponding empirical estimates. In sensitivity analyses in which HIV and HPV were assumed to increase each other's transmission risk, simulated associations were stronger but not inconsistent with empirical estimates. CONCLUSIONS: Although we cannot rule out the possibility that associations between HIV and HPV transmission may be due in part to biological interactions, these results suggest that observed associations could be explained entirely by residual confounding by behavioural factors and network-level effects that observational studies cannot account for.


Assuntos
Fatores de Confusão Epidemiológicos , Infecções por HIV/transmissão , Infecções por Papillomavirus/transmissão , Comportamento Sexual , Adolescente , Adulto , Teorema de Bayes , Estudos de Coortes , Feminino , HIV/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Papillomaviridae/fisiologia , Infecções por Papillomavirus/epidemiologia , Prevalência , Modelos de Riscos Proporcionais , Fatores de Risco , Parceiros Sexuais , África do Sul/epidemiologia , Adulto Jovem
7.
PLoS One ; 13(1): e0190166, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29293566

RESUMO

The objectives of the study were to investigate prevalence of cervical human papillomavirus (HPV) genotypes to inform HPV vaccination strategy in South Africa and to study factors associated with HPV prevalence. Sexually active, HIV-negative women, aged 16-22 years recruited from Soweto (n = 143) and Cape Town (n = 148) were tested for cervical HPV and other genital infections. Overall HPV prevalence was 66.7% (194/291) in young women. Cape Town women were more likely to have multiple HPV infections than the Soweto women (48.0%, 71/148 versus 35.0%, 50/143 respectively, p = 0.033) and probable HR-HPV types (34.5%, 51/148 versus 21.7%, 31/143 respectively, p = 0.022). The most frequently detected HPV types were HPV-16 (11.7%), HPV-58 (10.3%), HPV-51 (8.9%), HPV-66 (8.6%), HPV-18 and HPV-81 (7.6% each). HPV types targeted by the bivalent HPV vaccine (HPV-16/18) were detected in 18.6% (54/291) of women, while those in the quadrivalent vaccine (HPV-6/11/16/18) were detected in 24.7% (72/291) of women; and those in the nonavalent vaccine (HPV-6/11/16/18/31/33/45/52/58) were detected in 38.5% (112/291) of women. In a multivariable analysis, bacterial vaginosis remained significantly associated with HPV infection (OR: 4.0, 95% CI: 1.4-12.6). Women were more likely to be HPV positive if they had received treatment for STI during the past 6-months (OR: 3.4, 95% CI: 1.1-12.4) or if they had ever been pregnant (OR: 2.3, 95% CI: 1.1-5.5). Compared to women who reported only one sexual partner, those with increased number of lifetime sex partners were more likely to have HPV (4-10 partners: OR: 2.9, 95% CI: 1.1-8.0). The high prevalence of HPV types targeted by the nonavalent HPV vaccine encourages the introduction of this vaccine and catch-up HPV vaccination campaigns in South Africa. The high burden of BV and concurrent STIs also highlights the need to improve the prevention and appropriate management of sexually-acquired and other genital tract infections in South African youth.


Assuntos
Alphapapillomavirus/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Vacinas contra Papillomavirus/administração & dosagem , Adolescente , Adulto , Feminino , Humanos , Infecções por Papillomavirus/prevenção & controle , Infecções por Papillomavirus/virologia , Prevalência , África do Sul/epidemiologia , Adulto Jovem
8.
PLoS One ; 9(5): e96867, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24806474

RESUMO

BACKGROUND: Few studies have evaluated access to and retention in pre-ART care. OBJECTIVES: To evaluate the proportion of People Living With HIV (PLWH) in pre-ART and ART care and factors associated with retention in pre-ART and ART care from a community cohort. METHODS: A cross sectional survey was conducted from February - April 2011. Self reported HIV positive, negative or participants of unknown status completed a questionnaire on their HIV testing history, access to pre-ART and retention in pre-ART and ART care. RESULTS: 872 randomly selected adults who reported being HIV positive in the ZAMSTAR 2010 prevalence survey were included and revisited. 579 (66%) reconfirmed their positive status and were included in this analysis. 380 (66%) had initiated ART with 357 of these (94%) retained in ART care. 199 (34%) had never initiated ART of whom 186 (93%) accessed pre-ART care, and 86 (43%) were retained in pre-ART care. In a univariable analysis none of the factors analysed were significantly associated with retention in care in the pre-ART group. Due to the high retention in ART care, factors associated with retention in ART care, were not analysed further. CONCLUSION: Retention in ART care was high; however it was low in pre-ART care. The opportunity exists, if care is better integrated, to engage with clients in primary health care facilities to bring them back to, and retain them in, pre-ART care.


Assuntos
Terapia Antirretroviral de Alta Atividade , Infecções por HIV/epidemiologia , Infecções por HIV/terapia , Retenção Psicológica , Adolescente , Adulto , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Estudos Transversais , Feminino , HIV/efeitos dos fármacos , HIV/patogenicidade , Infecções por HIV/patologia , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , África do Sul , Adulto Jovem
9.
PLoS One ; 8(7): e69437, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23922711

RESUMO

INTRODUCTION: Swaziland's severe HIV epidemic inspired an early national response since the late 1980s, and regular reporting of program outcomes since the onset of a national antiretroviral treatment (ART) program in 2004. We assessed effectiveness outcomes and mortality trends in relation to ART, HIV testing and counseling (HTC), tuberculosis (TB) and prevention of mother to child transmission (PMTCT). METHODS: Data triangulated include intervention coverage and outcomes according to program registries (2001-2010), hospital admissions and deaths disaggregated by age and sex (2001-2010) and population mortality estimates from the 1997 and 2007 censuses and the 2007 demographic and health survey. RESULTS: By 2010, ART reached 70% of the estimated number of people living with HIV/AIDS with CD4<350/mm(3), with progressively improving patient retention and survival. As of 2010, 88% of health facilities providing antenatal care offered comprehensive PMTCT services. The HTC program recorded a halving in the proportion of adults tested who were HIV-infected; similarly HIV infection rates among HIV-exposed babies halved from 2007 to 2010. Case fatality rates among hospital patients diagnosed with HIV/AIDS started to decrease from 2005-6 in adults and especially in children, contrasting with stable case fatality for other causes including TB. All-cause child in-patient case fatality rates started to decrease from 2005-6. TB case notifications as well as rates of HIV/TB co-infection among notified TB patients continued a steady increase through 2010, while coverage of HIV testing and CPT for co-infected patients increased to above 80%. CONCLUSION: Against a background of high, but stable HIV prevalence and decreasing HIV incidence, we documented early evidence of a mortality decline associated with the expanded national HIV response since 2004. Attribution of impact to specific interventions (versus natural epidemic dynamics) will require additional data from future household surveys, and improved routine (program, surveillance, and hospital) data at district level.


Assuntos
Terapia Antirretroviral de Alta Atividade/estatística & dados numéricos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Programas Nacionais de Saúde/estatística & dados numéricos , Saúde Pública/estatística & dados numéricos , Tuberculose/complicações , Tuberculose/prevenção & controle , Adolescente , Adulto , Causas de Morte , Comorbidade , Aconselhamento , Essuatíni/epidemiologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Prevalência , Análise de Sobrevida , Resultado do Tratamento , Tuberculose/epidemiologia , Adulto Jovem
10.
PLoS One ; 7(11): e49661, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23166743

RESUMO

BED estimates of HIV incidence from cross-sectional surveys are obtained by restricting, to fixed time T, the period over which incidence is estimated. The appropriate mean recency duration (Ω(T)) then refers to the time where BED optical density (OD) is less than a pre-set cut-off C, given the patient has been HIV positive for at most time T. Five methods, tested using data for postpartum women in Zimbabwe, provided similar estimates of Ω(T) for C = 0.8: i) The ratio (r/s) of the number of BED-recent infections to all seroconversions over T = 365 days: 192 days [95% CI 168-216]. ii) Linear mixed modeling (LMM): 191 days [95% CI 174-208]. iii) Non-linear mixed modeling (NLMM): 196 days [95% CrI 188-204]. iv) Survival analysis (SA): 192 days [95% CI 168-216]. Graphical analysis: 193 days. NLMM estimates of Ω(T)--based on a biologically more appropriate functional relationship than LMM--resulted in best fits to OD data, the smallest variance in estimates of VT, and best correspondence between BED and follow-up estimates of HIV incidence, for the same subjects over the same time period. SA and NLMM produced very similar estimates of Ω(T) but the coefficient of variation of the former was .3 times as high. The r/s method requires uniformly distributed seroconversion events but is useful if data are available only from a single follow-up. The graphical method produces the most variable results, involves unsound methodology and should not be used to provide estimates of Ω(T). False-recent rates increased as a quadratic function of C: for incidence estimation C should thus be chosen as small as possible, consistent with an adequate resultant number of recent cases, and accurate estimation of Ω(T). Inaccuracies in the estimation of Ω(T) should not now provide an impediment to incidence estimation.


Assuntos
Infecções por HIV/epidemiologia , Soropositividade para HIV , HIV-1 , Técnicas Imunoenzimáticas , Estudos Transversais , Feminino , Seguimentos , Infecções por HIV/diagnóstico , HIV-1/imunologia , Humanos , Técnicas Imunoenzimáticas/métodos , Incidência , Modelos Estatísticos , Fatores de Tempo , Zimbábue/epidemiologia
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