Silva P. Kouyoumjian
Cornell University
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Sexually Transmitted Infections | 2013
Ghina Mumtaz; Silva P. Kouyoumjian; Nahla Hilmi; Ahmed Zidouh; Houssine El Rhilani; Kamal Alami; Aziza Bennani; Eleanor Gouws; Peter D. Ghys; Laith J. Abu-Raddad
Objectives Building on a wealth of new empirical data, the objective of this study was to estimate the distribution of new HIV infections in Morocco by mode of exposure using the modes of transmission (MoT) mathematical model. Methods The MoT model was implemented within a collaboration with the Morocco Ministry of Health and the Joint United Nations Programme on HIV/AIDS. The model was parameterised through a comprehensive review and synthesis of HIV and risk behaviour data in Morocco, mainly through the Middle East and North Africa HIV/AIDS Synthesis Project. Uncertainty analyses were used to assess the reliability of and uncertainty around our calculated estimates. Results Female sex workers (FSWs), clients of FSWs, men who have sex with men (MSM) and injecting drug users (IDUs) contributed 14%, 24%, 14% and 7% of new HIV infections, respectively. Two-thirds (67%) of new HIV infections occurred among FSWs, clients of FSWs, MSM and IDUs, or among the stable sexual partners of these populations. Casual heterosexual sex contributed 7% of HIV infections. More than half (52%) of HIV incidence is among females, but 71% of these infections are due to an infected spouse. The vast majority of HIV infections among men (89%) are due to high-risk behaviour. A very small HIV incidence is predicted to arise from medical injections or blood transfusions (0.1%). Conclusions The HIV epidemic in Morocco is driven by HIV incidence in high-risk population groups, with commercial heterosexual sex being the largest contributor to incidence. There is a need to focus HIV response more on these populations, mainly through proactive and sustainable HIV surveillance, and the expansion and increased geographical coverage of services such as condom promotion among FSWs, voluntary counselling and testing, harm reduction and treatment.
International Journal of Std & Aids | 2013
Silva P. Kouyoumjian; Ghina Mumtaz; Nahla Hilmi; Ahmed Zidouh; H El rhilani; Kamal Alami; Aziza Bennani; Eleanor Gouws; Peter D. Ghys; Laith J. Abu-Raddad
Summary Morocco has made significant strides in building its HIV research capacity. Based on a wealth of empirical data, the objective of this study was to conduct a comprehensive and systematic literature review and analytical synthesis of HIV epidemiological evidence in this country. Data were retrieved using three major sources of literature and data. HIV transmission dynamics were found to be focused in high-risk populations, with female sex workers (FSWs) and clients contributing the largest share of new HIV infections. There is a pattern of emerging epidemics among some high-risk populations, and some epidemics, particularly among FSWs, appear to be established and stable. The scale of the local HIV epidemics and populations affected show highly heterogeneous geographical distribution. To optimize the national HIV response, surveillance and prevention efforts need to be expanded among high-risk populations and in geographic settings where low intensity and possibly concentrated HIV epidemics are emerging or are already endemic.
PLOS ONE | 2016
Karima Chaabna; Silva P. Kouyoumjian; Laith J. Abu-Raddad
Objectives To characterize hepatitis C virus (HCV) epidemiology and assess country-specific population-level HCV prevalence in four countries in the Middle East and North Africa (MENA) region: Djibouti, Somalia, Sudan, and Yemen. Methods Reports of HCV prevalence were systematically reviewed as per PRISMA guidelines. Pooled HCV prevalence estimates in different risk populations were conducted when the number of measures per risk category was at least five. Results We identified 101 prevalence estimates. Pooled HCV antibody prevalence in the general population in Somalia, Sudan and Yemen was 0.9% (95% confidence interval [95%CI]: 0.3%–1.9%), 1.0% (95%CI: 0.3%–1.9%) and 1.9% (95%CI: 1.4%–2.6%), respectively. The only general population study from Djibouti reported a prevalence of 0.3% (CI: 0.2%–0.4%) in blood donors. In high-risk populations (e.g., haemodialysis and haemophilia patients), pooled HCV prevalence was 17.3% (95%CI: 8.6%–28.2%) in Sudan. In Yemen, three studies of haemodialysis patients reported HCV prevalence between 40.0%-62.7%. In intermediate-risk populations (e.g.. healthcare workers, in patients and men who have sex with men), pooled HCV prevalence was 1.7% (95%CI: 0.0%–4.9%) in Somalia and 0.6% (95%CI: 0.4%–0.8%) in Sudan. Conclusion National HCV prevalence in Yemen appears to be higher than in Djibouti, Somalia, and Sudan as well as most other MENA countries; but otherwise prevalence levels in this subregion are comparable to global levels. The high HCV prevalence in patients who have undergone clinical care appears to reflect ongoing transmission in clinical settings. HCV prevalence in people who inject drugs remains unknown.
Sexually Transmitted Infections | 2013
Hanan F Saba; Silva P. Kouyoumjian; Ghina Mumtaz; Laith J. Abu-Raddad
Objectives The Middle East and North Africa (MENA) region is perceived to have limited HIV data. The objective of this study was to quantitatively characterise the progress in HIV research in this region since the discovery of the epidemic. Methods Four indices were defined and implemented to measure the progress of HIV research using the PubMed, Embase, MENA HIV/AIDS Epidemiology Synthesis Project and US Census Bureau HIV/AIDS Surveillance databases. The four indices provide complementary measures to characterise different aspects of the progress of HIV research. Results A total of 2118, 2352, 683 and 4889 records were identified through the PubMed, the Embase, the Synthesis Project and the HIV Prevalence indices, respectively. The proportion of the total global HIV records that relate to MENA is 1.2%. Overall, the indices show steady progress in the number of new records every year, with an accelerated pace in the last few years. The rate of progress in MENA was also higher than the rate of progress in HIV records globally. There is no evidence so far of stabilisation or a peak in the number of new records year by year. About half of the records were produced after the year 2005. The number of records shows large heterogeneity across countries. Conclusions MENA has witnessed a rapid growth in HIV research over the last decade. However, there are still large gaps in HIV scientific evidence in the region, and the progress is far from being uniform across countries. Ongoing and future research needs to be geared towards academic standard and production of scientific publications.
Scientific Reports | 2018
Silva P. Kouyoumjian; Hiam Chemaitelly; Laith J. Abu-Raddad
Egypt is the most affected nation by hepatitis C virus (HCV) and needs a comprehensive characterization of HCV epidemiology to inform the scale-up of treatment and prevention programs. Systematic reviews, meta-analyses, and meta-regressions were conducted. A total of 25 incidence, 259 prevalence, and 47 genotype studies were identified. Incidence and prevalence levels were high across all populations. Genotype 4 accounted for 94.1% of infections with a relative Shannon Diversity Index of only 14.4%. Pooled mean HCV prevalence was estimated at 11.9% (95% CI = 11.1–12.6%) among the general population, 55.6% (95% CI = 49.4–61.7%) among populations at high risk, 14.3% (95% CI = 10.3–18.8%) among populations at intermediate risk, 56.0% (95% CI = 50.4–61.6%) among populations with liver-related conditions, and 35.0% (95% CI = 27.3–43.1%) among special clinical populations. Mean HCV viremic rate was estimated at 66.7% (95% CI = 61.7–71.5%). Meta-regression indicated 6% lower odds for HCV prevalence for each one-year increment in publication year (AOR = 0.94; 95% CI = 0.92–0.96). HCV prevalence is high with evidence for ongoing transmission mainly through healthcare. Genotype diversity is low with genotype 4 dominance. Two-thirds of antibody-positive Egyptians are chronically infected and need treatment. Clinical populations should be prioritized for screening. Despite the large-scale epidemic, prevalence appears to be declining rapidly consistent with a contracting epidemic.
Journal of Medical Virology | 2018
Sarwat Mahmud; Zaina Al-Kanaani; Hiam Chemaitelly; Karima Chaabna; Silva P. Kouyoumjian; Laith J. Abu-Raddad
Our objective was to characterize the distribution, diversity and patterns of hepatitis C virus (HCV) genotypes in the Middle East and North Africa (MENA). Source of data was a database of HCV genotype studies in MENA populated using a series of systematic literature searches. Pooled mean proportions were estimated for each genotype and by country using DerSimonian‐Laird random‐effects meta‐analyses. Genotype diversity within countries was assessed using Shannon Diversity Index. Number of chronic infections by genotype and country was calculated using the pooled proportions and country‐specific numbers of chronic infection. Analyses were conducted on 338 genotype studies including 82 257 genotyped individuals. Genotype 1 was dominant (≥50%) in Algeria, Iran, Morocco, Oman, Tunisia, and UAE, and was overall ubiquitous across the region. Genotype 2 was common (10‐50%) in Algeria, Bahrain, Libya, and Morocco. Genotype 3 was dominant in Afghanistan and Pakistan. Genotype 4 was dominant in Egypt, Iraq, Jordan, Palestine, Qatar, Saudi Arabia, and Syria. Genotypes 5, 6, and 7 had limited or no presence across countries. Genotype diversity varied immensely throughout MENA. Weighted by population size, MENAs chronic infections were highest among genotype 3, followed by genotype 4, genotype 1, genotype 2, genotype 5, and genotype 6. Despite ubiquitous presence of genotype 1, the vast majority of chronic infections were of genotypes 3 or 4, because of the sizable epidemics in Pakistan and Egypt. Three sub‐regional patterns were identified: genotype 3 pattern centered in Pakistan, genotype 4 pattern centered in Egypt, and genotype 1 pattern ubiquitous in most MENA countries.
Epidemiology and Infection | 2017
M. Harfouche; Hiam Chemaitelly; Sarwat Mahmud; K. Chaabna; Silva P. Kouyoumjian; Z. Al Kanaani; Laith J. Abu-Raddad
We aimed to investigate hepatitis C virus (HCV) epidemiology among hemodialysis (HD) patients in the Middle East and North Africa (MENA). Our data source was an HCV biological measures database populated through systematic literature searches. Descriptive epidemiologic syntheses, effects meta-analyses and meta-regressions, and genotype analyses were conducted. We analyzed 289 studies, including 106 463 HD patients. HCV incidence ranged between 0 and 100% as seroconversion risk, and between 0 and 14·7 per 1000 person-years as incidence rate. The regional pooled mean estimate was 29·2% (95% CI: 25·6-32·8%) for HCV antibody positive prevalence and 63·0% (95% CI: 55·4-70·3%) for the viremic rate. Region within MENA, country income group, and year of data collection were associated with HCV prevalence; year of data collection adjusted odds ratio was 0·92 (95% CI: 0·90-0·95). Genotype diversity varied across countries with four genotypes documented regionally: genotype 1 (39·3%), genotype 2 (5·7%), genotype 3 (29·6%), and genotype 4 (25·4%). Our findings showed that one-third of HD patients are HCV antibody positive and one-fifth are chronic carriers and can transmit the infection. However, HCV prevalence is declining. In context of growing HD patient population and increasing HCV treatment availability, it is critical to improve standards of infection control in dialysis and expand treatment coverage.
Royal Society Open Science | 2018
Zaina Al Kanaani; Sarwat Mahmud; Silva P. Kouyoumjian; Laith J. Abu-Raddad
To characterize hepatitis C virus (HCV) epidemiology in Pakistan and estimate the pooled mean HCV antibody prevalence in different risk populations, we systematically reviewed all available records of HCV incidence and/or prevalence from 1989 to 2016, as informed by the Cochrane Collaboration Handbook. This systematic review was reported following the PRISMA guidelines. Populations were classified into six categories based on the risk of exposure to HCV infection. Meta-analyses were performed using DerSimonian and Laird random-effects models with inverse variance weighting. The search identified one HCV incidence study and 341 prevalence measures/strata. Meta-analyses estimated the pooled mean HCV prevalence at 6.2% among the general population, 34.5% among high-risk clinical populations, 12.8% among populations at intermediate risk, 16.9% among special clinical populations, 55.9% among populations with liver-related conditions and 53.6% among people who inject drugs. Most reported risk factors in analytical epidemiologic studies related to healthcare procedures. Pakistan is enduring an HCV epidemic of historical proportions—one in every 20 Pakistanis is infected. HCV plays a major role in liver disease burden in this country, and HCV prevalence is high in all-risk populations. Most transmission appears to be driven by healthcare procedures. HCV treatment and prevention must become a national priority.
PLOS ONE | 2017
Manale Harfouche; Hiam Chemaitelly; Silva P. Kouyoumjian; Sarwat Mahmud; Karima Chaabna; Zaina Al-Kanaani; Laith J. Abu-Raddad
Objectives To estimate hepatitis C virus (HCV) viremic rate, defined as the proportion of HCV chronically infected individuals out of all ever infected individuals, in the Middle East and North Africa (MENA). Methods Sources of data were systematically-gathered and standardized databases of the MENA HCV Epidemiology Synthesis Project. Meta-analyses were conducted using DerSimonian-Laird random-effects models to determine pooled HCV viremic rate by risk population or subpopulation, country/subregion, sex, and study sampling method. Random-effects meta-regressions were conducted to identify predictors of higher viremic rate. Results Analyses were conducted on 178 measures for HCV viremic rate among 19,593 HCV antibody positive individuals. In the MENA region, the overall pooled mean viremic rate was 67.6% (95% CI: 64.9–70.3%). Across risk populations, the pooled mean rate ranged between 57.4% (95% CI: 49.4–65.2%) in people who inject drugs, and 75.5% (95% CI: 61.0–87.6%) in populations with liver-related conditions. Across countries/subregions, the pooled mean rate ranged between 62.1% (95% CI: 50.0–72.7%) and 70.4% (95% CI: 65.5–75.1%). Similar pooled estimates were further observed by risk subpopulation, sex, and sampling method. None of the hypothesized population-level predictors of higher viremic rate were statistically significant. Conclusions Two-thirds of HCV antibody positive individuals in MENA are chronically infected. Though there is extensive variation in study-specific measures of HCV viremic rate, pooled mean estimates are similar regardless of risk population or subpopulation, country/subregion, HCV antibody prevalence in the background population, or sex. HCV viremic rate is a useful indicator to track the progress in (and coverage of) HCV treatment programs towards the set target of HCV elimination by 2030.
International Journal of Infectious Diseases | 2017
Silva P. Kouyoumjian; Houssine El Rhilani; Amina Latifi; Amina El Kettani; Hiam Chemaitelly; Kamal Alami; Aziza Bennani; Laith J. Abu-Raddad
OBJECTIVES The aim of this study was to assess HIV modes of exposure in Morocco at the national level and also for Souss-Massa-Drâa, the region most affected by HIV. Another aim was to assess the impact of different scenarios of select intervention packages. METHODS The Modes of Transmission Model was adapted and used, and was parameterized using quality bio-behavioral surveillance data among key populations, routine data sources, and literature reviews. RESULTS Nationally in 2013, the largest number of new infections occurred among clients of female sex workers (FSWs) (25%; 95% confidence interval (CI) 14-37%), followed by men who have sex with men (MSM) (22%; 95% CI 12-35%), HIV serodiscordant couples (22%; 95% CI 12-34%), FSWs (11%; 95% CI 6-18%), and people who inject drugs (5%; 95% CI 2-9%). A similar pattern of results was observed in Souss-Massa-Drâa, but the HIV incidence rate was four-fold that at the national level. Different scenarios of feasible intervention packages reduced HIV incidence by 8-44%. CONCLUSIONS Commercial heterosexual sex networks continue as the leading driver of the epidemic, with half of HIV incidence. A quarter of new infections occurred among MSM, a third of which in Souss-Massa-Drâa. Feasible expanded coverage of interventions could lead to large reductions in incidence.