Characterizing the temporal evolution of the hepatitis C virus epidemic in Pakistan

Hepatitis C risk score as a tool to identify individuals with HCV infection: a demonstration and cross-sectional epidemiological study in Egypt

OBJECTIVES

Hepatitis C virus (HCV) infection poses a global health challenge. By the end of 2021, the WHO estimated that less than a quarter of global HCV infections had been diagnosed. There is a need for a public health tool that can facilitate the identification of people with HCV infection and link them to testing and treatment, and that can be customised for each country.

METHODS

We derived and validated a risk score to identify people with HCV in Egypt and demonstrated its utility. Using data from the 2008 and 2014 Egypt Demographic and Health Surveys, two risk scores were constructed through multivariable logistic regression analysis. A range of diagnostic metrics was then calculated to evaluate the performance of these scores.

RESULTS

The 2008 and 2014 risk scores exhibited similar dependencies on sex, age and type of place of residence. Both risk scores demonstrated high and similar areas under the curve of 0.77 (95% CI: 0.76 to 0.78) and 0.78 (95% CI: 0.77 to 0.80), respectively. For the 2008 risk score, sensitivity was 73.7% (95% CI: 71.5% to 75.9%), specificity was 68.5% (95% CI: 67.5% to 69.4%), positive predictive value (PPV) was 27.8% (95% CI: 26.4% to 29.2%) and negative predictive value (NPV) was 94.1% (95% CI: 93.5% to 94.6%). For the 2014 risk score, sensitivity was 64.0% (95% CI: 61.5% to 66.6%), specificity was 78.2% (95% CI: 77.5% to 78.9%), PPV was 22.2% (95% CI: 20.9% to 23.5%) and NPV was 95.7% (95% CI: 95.4% to 96.1%). Each score was validated by applying it to a different survey database than the one used to derive it.

CONCLUSIONS

Implementation of HCV risk scores is an effective strategy to identify carriers of HCV infection and to link them to testing and treatment at low cost to national programmes.

Prevalence of hepatitis B and C viruses among migrant workers in Qatar

Limited data exist on viral hepatitis among migrant populations. This study investigated the prevalence of current hepatitis B virus (HBV) infection and lifetime hepatitis C virus (HCV) infection among Qatar's migrant craft and manual workers (CMWs), constituting 60% of the country's population. Sera collected during a nationwide COVID-19 population-based cross-sectional survey on CMWs between July 26 and September 9, 2020, underwent testing for HBsAg and HCV antibodies. Reactive samples underwent confirmatory testing, and logistic regression analyses were employed to explore associations with HBV and HCV infections. Among 2528 specimens tested for HBV infection, 15 were reactive, with 8 subsequently confirmed positive. Three samples lacked sufficient sera for confirmatory testing but were included in the analysis through multiple imputations. Prevalence of current HBV infection was 0.4% (95% CI 0.2-0.7%). Educational attainment and occupation were significantly associated with current HBV infection. For HCV infection, out of 2607 specimens tested, 46 were reactive, and 23 were subsequently confirmed positive. Prevalence of lifetime HCV infection was 0.8% (95% CI 0.5-1.2%). Egyptians exhibited the highest prevalence at 6.5% (95% CI 3.1-13.1%), followed by Pakistanis at 3.1% (95% CI 1.1-8.0%). Nationality, geographic location, and occupation were significantly associated with lifetime HCV infection. HBV infection is relatively low among CMWs, while HCV infection falls within the intermediate range, both compared to global and regional levels.

Implementation of the HepClink test-and-treat community strategy targeting Pakistani migrants with hepatitis C living in Catalonia (Spain) compared with the current practice of the Catalan health system: budget impact analysis

OBJECTIVES

To perform a budget impact analysis of the HepClink test-and-treat strategy in which community health agents offer hepatitis C virus (HCV) testing, diagnosis and treatment to the Pakistani population living in Catalonia compared with the current practice of the Catalan health system (without targeted screening programmes).

METHODS

We estimated the population of adult Pakistani migrants registered at the primary care centres in Catalonia by means of the Information System for the Development of Research in Primary Care (n=37 972 in 2019, Barcelona health area). This cohort was followed for a time period of 10 years after HCV diagnosis (2019-2028). The statistical significance of the differences observed in the anti-HCV positivity rate between screened and non-screened was confirmed (α=0.05). The budget impact was calculated from the perspective of the Catalan Department of Health. Sensitivity analyses included different levels of participation in HepClink: pessimistic, optimistic and maximum.

RESULTS

The HepClink scenario screened a higher percentage of individuals (69.8%) compared with the current scenario of HCV care (39.7%). Viraemia was lower in the HepClink scenario compared with the current scenario (1.7% vs 2.5%, respectively). The budget impact of the HepClink scenario was €884 244.42 in 10 years.

CONCLUSIONS

Scaling up the HepClink strategy to the whole Catalan territory infers a high budget impact for the Department of Health and allows increasing the detection of viraemia (+17.8%) among Pakistani migrants ≥18 years. To achieve a sustainable elimination of HCV by improving screening and treatment rates, there is room for improvement at two levels. First, taking advantage of the fact that 68.08% of the Pakistani population had visited their primary care physicians to reinforce targeted screening in primary care. Second, to use HepClink at the community level to reach individuals with reluctance to use healthcare services.

Treatment as prevention for hepatitis C virus in the Middle East and North Africa: a modeling study

Background

Direct-acting antivirals opened an opportunity for eliminating hepatitis C virus (HCV) infection in the Middle East and North Africa (MENA), the region most affected by HCV infection. Impact of HCV treatment as prevention (HCV-TasP) was investigated in 19 MENA countries.

Methods

An age-structured mathematical model was used to assess program impact using epidemiologic and programming measures. The model was fitted to a database of systematically gathered HCV antibody prevalence data. Two main scenarios were investigated for the treatment roll-out to achieve (i) 80% reduction in HCV incidence by 2030, and (ii) incidence rate < 1 per 100,000 person-years by 2030.

Results

In the target-80%-incidence-reduction scenario, number of treatments administrated by 2030 ranged from 2,610 in Lebanon to 180,416 in Sudan with a median of 53,079, and treatment coverage ranged between 40.2 and 78.4% with a median of 60.4%. By 2030, prevalence of chronic infection ranged between 0.0 and 0.3% with a median of 0.1%, and incidence rate, per 100,000 person-years, ranged between 0.9 and 16.3 with a median of 3.2. Program-attributed reduction in incidence rate ranged between 47.8 and 81.9% with a median of 68.5%, and number of averted infections ranged between 401 and 68,499 with a median of 8,703. Number of treatments needed to prevent one new infection ranged from 1.7 in Oman to 25.9 in Tunisia with a median of 6.5. In the target incidence rate  < 1 per 100,000 person-years scenario, number of treatments administrated by 2030 ranged from 3,470 in Lebanon to 211,912 in Sudan with a median of 54,479, and treatment coverage ranged between 55.5 and 95.9% with a median of 87.5%. By 2030, prevalence of chronic infection was less than 0.1%, and incidence rate, per 100,000 person-years, reached less than 1. Program-attributed reduction in incidence rate ranged between 61.0 and 97.5% with a median of 90.7%, and number of averted infections ranged between 559 and 104,315 with a median of 12,158. Number of treatments needed to prevent one new infection ranged from 1.3 in Oman to 25.9 in Tunisia with a median of 5.5.

Conclusion

HCV-TasP is an effective and indispensable prevention intervention to control MENA's HCV epidemic and to achieve elimination by 2030.

Characterizing trends and associations for hepatitis C virus antibody prevalence in the Middle East and North Africa: meta-regression analyses

This study characterized population-level trends and associations with hepatitis C virus (HCV) antibody (Ab) prevalence in the Middle East and North Africa (MENA). Data source was the standardized and systematically gathered MENA HCV Epidemiology Synthesis Project Database. Random-effects univariable and multivariable meta-regressions were conducted. 2,621 HCV Ab prevalence measures on 49,824,108 individuals were analyzed. In the analysis including all populations, 71% of the variation in prevalence was explained, mostly by at-risk population type. Compared to the general population, prevalence was 23-fold higher among people who inject drugs, and 14-fold higher among high-risk clinical populations. In the analysis including only the general population, 67% of the variation in prevalence was explained, mostly by country/subregion. Compared to Afghanistan, prevalence was highest in Egypt and Pakistan. Prevalence in the general population was declining at a rate of 4% per year, but outside the general population, the decline was at only 1% per year. HCV Ab prevalence in MENA is declining rapidly, but this decline is largely occurring in the general population following introduction of blood and injection safety measures. The decline in populations at higher risk of exposure is slow and below the level needed to achieve HCV elimination by 2030.

Pilot hepatitis C micro-elimination strategy in Pakistani migrants in Catalonia through a community intervention

BACKGROUND AND AIMS

Pakistani migrants in Catalonia, Spain, could have high hepatitis C virus (HCV) prevalence. The aims of the HepClink study were (i) to implement and assess the quality of a micro-elimination strategy based on a community intervention and (ii) to obtain data from primary care (PC) registries as a baseline comparator.

METHODS

The community intervention targeted Pakistani adults and consisted of education, screening and simplified access to treatment. Quality indicators were calculated (effectiveness, impact and acceptability). The testing rate, the prevalence of HCV antibodies and HCV-RNA were compared with those observed in the Pakistani population accessing PC in the previous year.

RESULTS

A total of 505 participants were recruited through the community intervention (64.6% men, median 37 years) vs those accessing PC (N = 25 455, 70.9% men, median 38 years). Among study participants, 35.1% did not know about HCV and 9.7% had been previously tested. The testing rate in the community intervention was 99.4% vs 50.7% in PC. Prevalence was 4.6% vs 7.1% (p = .008) for HCV antibodies and 1.4% (3/6 new diagnoses) vs 2.4% (p = .183) for HCV-RNA. Among the six viremic patients, three began treatment within the intervention and two through the usual circuit and all completed the full course.

CONCLUSIONS

This novel community intervention was well accepted and effective at reaching a Pakistani migrant population with a low-level knowledge of HCV and largely not tested before. The observed prevalence and the high unawareness of their HCV status justify a targeted screening in this group both in the community and in PC.

Prevalence and assessment of the associated risk factors of hepatitis B and C infections in the low socioeconomic communities

Aim: This study determined the prevalence and risk factors associated with hepatitis B and C among the low socioeconomic population. Materials & methods: A total of 1004 participants were screened for hepatitis B/C infection and risk factors from six different localities of Islamabad, Pakistan Results: The prevalence rate of hepatitis B and C was 1 and 4%, respectively. Chi-square test showed hepatitis B/C infection was related with marital status, hepatitis B vaccination, blood recipients and family income. Multivariable analysis showed hepatitis B vaccination, exposure to therapeutic injections, dental visits, exposure to HCV patients and age of participants were independently associated with hepatitis C infection. Conclusion: The risk of hepatitis B/C infection is multifactorial and the population needs to be vaccinated at a larger scale to avoid outbreaks.

Hepatitis C virus among blood donors and general population in Middle East and North Africa: Meta-analyses and meta-regressions

BACKGROUND

Despite the Middle East and North Africa (MENA) Region reported to have the highest prevalence of hepatitis C virus (HCV) globally, HCV infection levels in the majority of MENA countries remain inadequately characterized. Blood donor data have been previously used as a proxy to assess levels and trends of HCV in the general population, however, it is unclear how comparable these populations are in MENA and whether blood donors provide an appropriate proxy.

AIM

To delineate HCV epidemiology among blood donors and the general population in the MENA.

METHODS

The data source was the systematically gathered MENA HCV Epidemiology Synthesis Project Database. Random-effects meta-analyses and meta-regressions were conducted. For comparison, analyses were conducted for Europe, utilizing the Hepatitis C Prevalence Database of the European Centre for Disease Prevention and Control.

RESULTS

One thousand two hundred and thirteen HCV antibody prevalence measures and 84 viremic rate measures were analyzed for MENA. Three hundred and seventy-seven antibody prevalence measures were analyzed for Europe. In MENA, pooled mean prevalence was 1.58% [95% confidence interval (CI): 1.48%–1.69%] among blood donors and 4.49% (95%CI: 4.10%–4.90%) in the general population. In Europe, pooled prevalence was 0.11% (95%CI: 0.10%–0.13%) among blood donors and 1.59% (95%CI: 1.25%–1.97%) in the general population. Prevalence in the general population was 1.72-fold (95%CI: 1.50–1.97) higher than that in blood donors in MENA, but it was 15.10-fold (95%CI: 11.48–19.86) higher in Europe. Prevalence was declining at a rate of 4% per year in both MENA and Europe [adjusted risk ratio: 0.96 (95%CI: 0.95–0.97) in MENA and 0.96 (95%CI: 0.92–0.99) in Europe]. Pooled mean viremic rate in MENA was 76.29% (95%CI: 67.64%–84.02%) among blood donors and 65.73% (95%CI: 61.03%–70.29%) in the general population.

CONCLUSION

Blood donor data provide a useful proxy for HCV infection in the wider population in MENA, but not Europe, and could improve HCV burden estimations and assess progress toward HCV elimination by 2030.

Hepatitis C virus: Its prevalence, risk factors and genotype distribution in Pakistan

Hepatitis C is a dangerous liver disease transmitted by Hepatitis C virus (HCV). HCV constitutes an important health issue in Pakistan. In Pakistani setting HCV is found frequently and is recognized as an alarming health problem. In this cross sectional study we reviewed published data regarding the seroprevalence of hepatitis C in general community, blood donors and pregnant females and risk factors linked with its occurrence in Pakistan. Data retrieved from163 studies published from 2001 to 2022 was utilized and weighted mean was calculated. Data of 1,875,232 individuals was collected and arranged into three groups, depending upon the population type such as (1) general population, (2) pregnant women, (3) blood donors. General population (765,426) and blood donors (973,260) formed the most of population. Mean Hepatitis C virus prevalence in general public and blood donors was 16.47% and 8.2% respectively. In pregnant females (136,546) the mean frequency was 9.3%. This study exhibits that the frequency of Hepatitis C in general population, pregnant females and blood donors groups was 11.32%. The data suggested that risks factors for transmitting HCV infection in Pakistan include unsterilized needle use, blood transfusions, shaving by barbers, lack of trained staff, needle stick injuries, injection drug users, household contacts/spousal transmission, unsterilized dental and surgical Instruments, improper disposal of hospital waste, poor infra-structure and others. The frequency of HCV infection is distressing in Pakistan. Health education and awareness programs are needed for decreasing Hepatitis C infection in Pakistan. The data necessitate the implementation of preventive and remedial approaches to decrease the disease load and mortality in Pakistan.

Hepatitis C virus DNA vaccines: a systematic review

BACKGROUND

Vaccination against HCV is an effective measure in reduction of virus-related public health burden and mortality. However, no prophylactic vaccine is available as of yet. DNA-based immunization is a promising modality to generate cellular and humoral immune responses. The objective of this study is to provide a systematic review of HCV DNA vaccines and investigate and discuss the strategies employed to optimize their efficacies.

METHODS

MEDLINE (PubMed), Web of Science, Scopus, ScienceDirect, and databases in persian language including the Regional Information Centre for Science & Technology (RICeST), the Scientific Information Database and the Iranian Research Institute for Information Science and Technology (IranDoc) were examined to identify studies pertaining to HCV nucleic acid vaccine development from 2000 to 2020.

RESULTS

Twenty-seven articles were included. Studies related to HCV RNA vaccines were yet to be published. A variety of strategies were identified with the potential to optimize HCV DNA vaccines such as incorporating multiple viral proteins and molecular tags such as HBsAg and Immunoglobulin Fc, multi-epitope expression, co-expression plasmid utilization, recombinant subunit immunogens, heterologous prime-boosting, incorporating NS3 mutants in DNA vaccines, utilization of adjuvants, employment of less explored methods such as Gene Electro Transfer, construction of multi- CTL epitopes, utilizing co/post translational modifications and polycistronic genes, among others. The effectiveness of the aforementioned strategies in boosting immune response and improving vaccine potency was assessed.

CONCLUSIONS

The recent progress on HCV vaccine development was examined in this systematic review to identify candidates with most promising prophylactic and therapeutic potential.

Association of blood groups with hepatitis C viremia

Hepatitis C virus remained a public health problem with approximately half of the patients untreated and undiagnosed. Chronic HCV is a leading cause of cirrhosis, fibrosis, hepatocellular carcinoma and other hepatic morbidities. Active HCV has a prevalence rate of about 1% (71 million). By July, 2019, 10 million population of Pakistan was declared to have active HCV infection. According to World Health Organization, 23,720 people died of hepatitis-related complexities in Pakistan in 2016. Individuals with certain types of ABO blood groups were more susceptible to diverse kinds of infections. For instance, blood types A and AB predisposed individuals to severe malaria, while type O conferred resistance to the many of the protozoan agent.

This study was designed to explore the association of hepatitis C viremia to blood groups, Rh factors, age and gender distribution among Pakistani population. Total 246 participants were screened for HCV in Taqwa diagnostics laboratory, Multan and 200 were found positive. They were divided into 4 groups on the basis of their age. First group included patients ranging from 17 to 25 (52), second, third and fourth group included patients from 26 to 34 (92), 35 to 43 (42) and 44 to above (14) respectively. Confirmed Hepatitis C patients were subjected to analysis of blood group, Rh factor and viral load. Results demonstrated that patients having ‘O’ blood group (60.37%) were reported for high viral load than any of the other blood groups in the patients of Southern Punjab, Pakistan. Furthermore, Rh-negative factor (26.42) was associated with high viral load than that of the Rh-positive factor (73.58). Disclosure practiced that age group (26–34) was reported for the high viral load than that of the any other group of this study. Females were more aggressively affected by HCV Viremia than male because the mean viral load among the females was higher than that of the males. Greater social awareness and gender-sensitive healthcare is necessary to improve the experiences of patients with HCV.

Forecasting the type 2 diabetes mellitus epidemic and the role of key risk factors in Oman up to 2050: Mathematical modeling analyses

AIMS/INTRODUCTION

To investigate and forecast type 2 diabetes mellitus epidemic, its related risk factors and cost in Oman by 2050.

MATERIALS AND METHODS

An age-structured mathematical model was used to characterize type 2 diabetes mellitus epidemiology and trends in Oman between 1990 and 2050. The model was parametrized using current and quality data, including six nationally representative population-based epidemiological surveys for type 2 diabetes mellitus and its key risk factors.

RESULTS

The projected type 2 diabetes mellitus prevalence increased from 15.2% in 2020 to 23.8% in 2050. The prevalence increased from 16.8 and 13.8% in 2020 among women and men to 26.3 and 21.4% in 2050, respectively. In 2020, 190,489 Omanis were living with type 2 diabetes mellitus compared with 570,227 in 2050. The incidence rate per 1,000 person-years changed from 8.3 in 2020 to 12.1 in 2050. Type 2 diabetes mellitus' share of Oman's national health expenditure grew by 36% between 2020 and 2050 (from 21.2 to 28.8%). Obesity explained 56.7% of type 2 diabetes mellitus cases in 2020 and 71.4% in 2050, physical inactivity explained 4.3% in 2020 and 2.7% in 2050, whereas smoking accounted for <1% of type 2 diabetes mellitus cases throughout 2020-2050. Sensitivity and uncertainty analyses affirmed these predictions.

CONCLUSIONS

The type 2 diabetes mellitus epidemic in Oman is expected to increase significantly over the next three decades, consuming nearly one-third of the national health expenditure. The type 2 diabetes mellitus burden is heavily influenced by obesity. Interventions targeting this single risk factor should be a national priority to reduce and control the burden of type 2 diabetes mellitus in Oman.

Analytic Characterization of the Herpes Simplex Virus Type 2 Epidemic in the United States, 1950-2050

Background

We analytically characterized the past, present, and future levels and trends of the national herpes simplex virus type 2 (HSV-2) epidemic in the United States.

Methods

A population-level mathematical model was constructed to describe HSV-2 transmission dynamics and was fitted to the data series of the National Health and Nutrition Examination Survey.

Results

Over 1950–2050, antibody prevalence (seroprevalence) increased rapidly from 1960, peaking at 19.9% in 1983 in those aged 15–49 years, before reversing course to decline to 13.2% by 2020 and 8.5% by 2050. Incidence rate peaked in 1971 at 11.9 per 1000 person-years, before declining by 59% by 2020 and 70% by 2050. Annual number of new infections peaked at 1 033 000 in 1978, before declining to 667 000 by 2020 and 600 000 by 2050. Women were disproportionately affected, averaging 75% higher seroprevalence, 95% higher incidence rate, and 71% higher annual number of infections. In 2020, 78% of infections were acquired by those 15–34 years of age.

Conclusions

The epidemic has undergone a major transition over a century, with the greatest impact in those 15–34 years of age. In addition to 47 million prevalent infections in 2020, high incidence will persist over the next 3 decades, adding >600 000 new infections every year.

Characterizing the historical role of parenteral antischistosomal therapy in hepatitis C virus transmission in Egypt

Background

Egypt is the nation most affected by hepatitis C virus (HCV) infection, following an epidemic of historic proportions. We aimed to characterize the epidemic’s historical evolution and to delineate the role of parenteral antischistosomal therapy (PAT) campaigns in transmission.

Methods

A mathematical model was constructed and analysed in order to understand HCV-transmission dynamics. The model was fitted to Egypt’s Demographic and Health Survey data and to a systematic database of HCV-prevalence data.

Results

The incidence rate peaked in 1966 at 15.7 infections per 1000 person-years—a period of time that coincides with the PAT campaigns—and rapidly declined thereafter, beginning the mid-1990s. The annual number of new infections peaked in 1993 at 581 200 (with rapid demographic growth), leading to a high-incidence-cohort effect, and declined to 67 800 by 2018. The number of individuals ever infected (1950–2018) was 16.4 million, with HCV prevalence peaking in 1979. The number of individuals ever exposed to PAT was 8.3 million; however, of these individuals, 7.3 million were alive in 1980 and only 3.5 million alive in 2018. The number of individuals ever infected due to PAT exposure was 963 900, with 850 200 individuals alive in 1980 and only 389 800 alive in 2018. The proportion of PAT-attributed prevalent infections peaked at 19.9% in 1972, declining to 5.5% by 2018.

Conclusions

PAT campaigns played an important role in HCV transmission, yet explain only 6% of infections—they appear to be a manifestation, rather than a cause, of the epidemic. A possible driver of the epidemic could be the mass expansion of inadequate-quality healthcare during PAT campaigns and subsequent decades. Despite a historic toll, the epidemic has been rapidly diminishing since the mid-1990s.

Epidemiological Impact of Novel Preventive and Therapeutic HSV-2 Vaccination in the United States: Mathematical Modeling Analyses

This study aims to inform herpes simplex virus type 2 (HSV-2) vaccine development, licensure, and implementation by delineating the population-level impact of vaccination. Mathematical models were constructed to describe the transmission dynamics in presence of prophylactic or therapeutic vaccines assuming 50% efficacy, with application to the United States. Catch-up prophylactic vaccination will reduce, by 2050, annual number of new infections by 58%, incidence rate by 60%, seroprevalence by 21%, and avert yearly as much as 350,000 infections. Number of vaccinations needed to avert one infection was only 50 by 2050, 34 by prioritizing those aged 15-19 years, 4 by prioritizing the highest sexual risk group, 43 by prioritizing women, and 47 by prioritizing men. Therapeutic vaccination of infected adults with symptomatic disease will reduce, by 2050, annual number of new infections by 12%, incidence rate by 13%, seroprevalence by 4%, and avert yearly as much as 76,000 infections. Number of vaccinations needed to avert one infection was eight by 2050, two by prioritizing those aged 15-19 years, three by prioritizing the highest sexual risk group, seven by prioritizing men, and ten by prioritizing women. HSV-2 vaccination offers an impactful and cost-effective intervention to prevent genital herpes medical and psychosexual disease burden.

The status of hepatitis C virus infection among people who inject drugs in the Middle East and North Africa

BACKGROUND AND AIMS

People who inject drugs (PWID) are a key population at high risk of hepatitis C virus (HCV) infection. The aim of this study was to delineate the epidemiology of HCV in PWID in the Middle East and North Africa (MENA).

METHODS

Syntheses of data were conducted on the standardized and systematically assembled databases of the MENA HCV Epidemiology Synthesis Project, 1989-2018. Random-effects meta-analyses and meta-regressions were performed. Meta-regression variables included country, study site, year of data collection and year of publication [to assess trends in HCV antibody prevalence over time], sample size and sampling methodology. Numbers of chronically infected PWID across MENA were estimated. The Shannon Diversity Index was calculated to assess genotype diversity.

RESULTS

Based on 118 HCV antibody prevalence measures, the pooled mean prevalence in PWID for all MENA was 49.3% [95% confidence interval (CI) = 44.4-54.1%]. The country-specific pooled mean ranged from 21.7% (95% CI = 4.9-38.6%) in Tunisia to 94.2% (95% CI = 90.8-96.7%) in Libya. An estimated 221 704 PWID were chronically infected, with the largest numbers found in Iran at 68 526 and in Pakistan at 46 554. There was no statistically significant evidence for a decline in HCV antibody prevalence over time. Genotype diversity was moderate (Shannon Diversity Index of 1.01 out of 1.95; 52.1%). The pooled mean percentage for each HCV genotype was highest in genotype 3 (42.7%) and in genotype 1 (35.9%).

CONCLUSION

Half of people who inject drugs in the Middle East and North Africa appear to have ever been infected with hepatitis C virus, but there are large variations in antibody prevalence among countries. In addition to > 200 000 chronically infected current people who inject drugs, there is an unknown number of people who no longer inject drugs who may have acquired hepatitis C virus during past injecting drug use. Harm reduction services must be expanded, and innovative strategies need to be employed to ensure accessibility to hepatitis C virus testing and treatment.

Key associations for hepatitis C virus genotypes in the Middle East and North Africa

This study aimed to investigate the epidemiology of hepatitis C virus (HCV) genotypes in the Middle East and North Africa (MENA) through an analytical and quantitative meta-regression methodology. For the most common genotypes 1, 3, and 4, country/subregion explained more than 77% of the variation in the distribution of each genotype. Genotype 1 was common across MENA, and was more present in high-risk clinical populations than in the general population. Genotype 3 was much more present in Afghanistan, Iran, and Pakistan than the rest of countries, and was associated with transmission through injecting drug use. Genotype 4 was broadly disseminated in Egypt in all populations, with overall limited presence elsewhere. While genotype 2 was more present in high-risk clinical populations and people who inject drugs, most of the variation in its distribution remained unexplained. Genotypes 5, 6, and 7 had low or no presence in MENA, limiting the epidemiological inferences that could be drawn. To sum up, geography is the principal determinant of HCV genotype distribution. Genotype 1 is associated with transmission through high-risk clinical procedures, while genotype 3 is associated with injecting drug use. These findings demonstrate the power of such analytical approach, which if extended to other regions and globally, can yield relevant epidemiological inferences.

Hepatitis C Virus Infection in Populations With Liver-Related Diseases in the Middle East and North Africa

We investigated hepatitis C virus (HCV) epidemiology in populations with liver‐related diseases (LRDs) in the Middle East and North Africa. The data source was standardized databases of HCV measures populated through systematic reviews. Random‐effects meta‐analyses and meta‐regressions were performed, and genotype diversity was assessed. Analyses were based on 252 HCV antibody prevalence measures, eight viremic rate measures, and 30 genotype measures on 132,358 subjects. Pooled mean prevalence in LRD populations was 58.8% (95% confidence interval [CI], 51.5%‐66.0%) in Egypt and 55.8% (95% CI, 49.1%‐62.4%) in Pakistan; these values were higher than in other countries, which had a pooled prevalence of only 15.6% (95% CI, 12.4%‐19.0%). Mean prevalence was highest in patients with hepatocellular carcinoma at 56.9% (95% CI, 50.2%‐63.5%) and those with cirrhosis at 50.4% (95% CI, 40.8%‐60.0%). Type of LRD population and country were the strongest predictors of prevalence, explaining 48.6% of the variation. No evidence for prevalence decline was found, but there was strong evidence for prevalence increase in Pakistan. A strong, positive association was identified between prevalence in the general population and that in LRD populations; the Pearson correlation coefficient ranged between 0.605 and 0.862. The pooled mean viremic rate was 75.5% (95% CI, 61.0%‐87.6%). Genotype 4 was most common (44.2%), followed by genotype 3 (34.5%), genotype 1 (17.0%), genotype 2 (3.5%), genotype 6 (0.5%), and genotype 5 (0.3%). Conclusion: HCV appears to play a dominant role in liver diseases in Egypt and Pakistan and has a growing role in Pakistan. Testing and treatment of LRD populations are essential to reduce disease burden and transmission and to reach HCV elimination by 2030.

Characterization of the hepatitis C virus epidemic in Pakistan

Background

With one in every 20 Pakistanis already infected, Pakistan has the second largest number of hepatitis C virus (HCV) infections globally. The aim of this study was to present a quantitative and analytical characterization of the HCV epidemic in Pakistan.

Methods

A standardized database of HCV antibody incidence and prevalence and HCV genotypes in all subpopulations was systematically assembled. Random-effects meta-analyses and random-effects meta-regressions were performed. Shannon Diversity Index was calculated to determine genotype diversity.

Results

The database included two incidence, 309 prevalence, and 48 genotype measures. Pooled mean HCV prevalence ranged between 7.0% (95% confidence interval (CI): 5.8–8.3%) in Sindh and 0.9% (95% CI: 0.1–2.4%) in Federally Administered Tribal Areas (F.A.T.A). Estimated number of chronically-infected persons ranged between 4.2 million in Punjab and 0.03 million in F.A.T.A. HCV prevalence was stable over time [adjusted odds ratio (AOR) of 1.0 (95% CI: 1.0–1.0)]. Population classification was the strongest predictor of HCV prevalence, explaining 51.8% of prevalence variation. Relative to the general population, HCV prevalence was higher in people who inject drugs [AOR of 23.8 (95% CI: 13.0–43.6)], populations with liver-related conditions [AOR of 22.3 (95% CI: 15.7–31.6)], and high-risk clinical populations [AOR of 7.8 (95% CI: 4.8–12.7)]. Low genotype diversity was observed (Shannon diversity index of 0.67 out of 1.95; 34.5%). There were only minor differences in genotype diversity by province, with genotype 3 being most common in all provinces.

Conclusion

Pakistan’s HCV epidemic shows homogeneity across the provinces, and over time. HCV prevalence is strikingly persistent at high level, with no evidence for a decline over the last three decades. Scale up of HCV treatment and prevention is urgently needed.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-4403-7) contains supplementary material, which is available to authorized users.

Treatment as prevention for hepatitis C virus in Pakistan: mathematical modelling projections

OBJECTIVE

Direct-acting antivirals have opened an opportunity for controlling hepatitis C virus (HCV) infection in Pakistan, where 10% of the global infection burden is found. We aimed to evaluate the implications of five treatment programme scenarios for HCV treatment as prevention (HCV-TasP) in Pakistan.

DESIGN

An age-structured mathematical model was used to evaluate programme impact using epidemiological and programme indicators.

SETTING

Total Pakistan population.

PARTICIPANTS

Total Pakistan HCV-infected population.

INTERVENTIONS

HCV treatment programme scenarios from 2018 up to 2030.

RESULTS

By 2030 across the five HCV-TasP scenarios, 0.6-7.3 million treatments were administered, treatment coverage reached between 3.7% and 98.7%, prevalence of chronic infection reached 2.4%-0.03%, incidence reduction ranged between 41% and 99%, program-attributed reduction in incidence rate ranged between 7.2% and 98.5% and number of averted infections ranged between 126 221 and 750 547. Annual incidence rate reduction in the first decade of the programme was around 6%-18%. Number of treatments needed to prevent one new infection ranged between 4.7-9.8, at a drug cost of about US$900. Cost of the programme by 2030, in the most ambitious elimination scenario, reached US$708 million. Stipulated WHO target for 2030 cannot be accomplished without scaling up treatment to 490 000 per year, and maintaining it for a decade.

CONCLUSION

HCV-TasP is a highly impactful and potent approach to control Pakistan's HCV epidemic and achieve elimination by 2030.

Who to Test for Hepatitis C Virus in the Middle East and North Africa?: Pooled Analyses of 2,500 Prevalence Measures, Including 49 Million Tests

Expanding hepatitis C virus (HCV) treatment coverage is challenged by limited testing and diagnosis. This study assessed the risk of exposure, for the Middle East and North Africa, by population, yields of testing, and program efficiency of testing strategies. A standardized and systematically assembled database of 2,542 HCV antibody prevalence studies on 49 million individuals was analyzed. Random effects meta-analyses were conducted to estimate pooled measures for risk of exposure, risk ratio (RR) of exposure, and yields of testing. Program expansion path curves were calculated to assess program efficiency. Countries clustered into two patterns: generalized versus concentrated epidemics. In generalized epidemics (Egypt and Pakistan) relative to general populations, RR of exposure was 6.8 for people who inject drugs (PWID), 6.7 for populations with liver conditions, and 5.0 for populations with high-risk health care exposures. In concentrated epidemics (remaining countries), corresponding RRs were 97.2, 45.1, and 22.2, respectively. In generalized epidemics, the number of tests needed to identify a chronic infection was 2.5 for PWID, 2.4 for populations with liver conditions, 2.7 for populations with high-risk health care exposures, and 14.2 for general populations. In concentrated epidemics, corresponding numbers were 2.8, 8.6, 5.1, and 222.2, respectively. Program expansion path curves demonstrated major gains in program efficiency by targeting specific populations. Risk of exposure varies immensely by population and shows a distinctive hierarchy, particularly in concentrated epidemics. Testing strategies can be much more efficient through population prioritization by risk of exposure. General population testing is not programmatically efficient in concentrated epidemics.

Epidemiology and Elimination of HCV-Related Liver Disease

Hepatitis C virus (HCV) infection, defined by active carriage of HCV RNA, affects nearly 1.0% of the worldwide population. The main risk factors include unsafe injection drug use and iatrogenic infections. Chronic HCV infection can promote liver damage, cirrhosis and hepatocellular carcinoma (HCC) in affected individuals. The advent of new second-generation, direct-acting antiviral (DAA) agents allow a virological cure in more than 90% of treated patients, and therefore prevent HCV-related complications. Recently, concerns have been raised regarding the safety of DAA-regimens in cirrhotic patients with respect to the occurrence and the recurrence of HCC. Here, we review the current available data on HCV epidemiology, the beneficial effects of therapy, and discuss the recent controversy with respect to the potential link with liver cancer. We also highlight the challenges that have to be overcome to achieve the ambitious World Health Organization objective of HCV eradication by 2030.

Hepatitis C virus infection spontaneous clearance: Has it been underestimated?

OBJECTIVES

Hepatitis C virus (HCV) clearance rate (f_clearance) is defined as the proportion of infected persons who will spontaneously clear their infection after acute infection. We aimed to estimate f_clearance using a novel approach that avoids limitations in existing estimates, and to clarify the link between f_clearance and HCV viremic rate-the latter being the proportion of RNA positivity among those antibody positive.

METHODS

A mathematical model was developed to describe HCV transmission. f_clearance was estimated by fitting the model to probability-based and nationally representative population-based data for Egypt (Egypt 2008 and Egypt 2015) and USA (NHANES A and NHANES B). Uncertainty and sensitivity analyses were conducted.

RESULTS

f_clearance was estimated at 39.9% (95% uncertainty interval (UI): 34.3%-46.4%) and 33.5% (95% UI: 29.2%-38.3%) for Egypt 2008 and Egypt 2015 data, respectively; and at 29.6% (23.0%-37.1%) and 39.9% (31.2%-51.0%) for NHANES A and NHANES B data, respectively. f_clearance was found related to HCV viremic rate through (approximately) the formula f_clearance=1.16 (1-HCV viremic rate). HCV viremic rate was higher with higher risk of HCV exposure. Robustness of results was demonstrated in uncertainty and sensitivity analyses.

CONCLUSION

One-third of HCV-infected persons clear their infection spontaneously, higher than earlier estimates-the immune-system capacity to clear HCV infection may have been underestimated.

The epidemiology of hepatitis C virus in Pakistan: systematic review and meta-analyses

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.

Individual-level key associations and modes of exposure for hepatitis C virus infection in the Middle East and North Africa: a systematic synthesis

PURPOSE

To identify, map, and synthesize the individual-level key associations and modes of exposure for hepatitis C virus (HCV) infection in the Middle East and North Africa (MENA), the most affected region by HCV.

METHODS

Source of data was the MENA HCV Epidemiology Synthesis Project database, populated through systematic literature searches. Risk factors determined to be statistically significant after adjustment for confounders were extracted and categorized into key associations or modes of exposure.

RESULTS

In total, 329 risk factors were identified from 109 articles in 14 of 24 MENA countries. Among key associations, age was most frequently reported (n = 39; 34.2%), followed by other infections/diseases (n = 20; 17.5%), and incarceration (n = 17; 14.9%). Among modes of exposure, health care-related exposures were most frequently reported (n = 127; 59.5%), followed by injecting drug use exposures (n = 45; 20.9%), community-related exposures (n = 34; 15.8%), and sexual-related exposures (n = 8; 3.7%). Blood transfusion, hemodialysis, surgical and other medical procedures, dental work, and medical injections were identified as key health care-related exposures.

CONCLUSIONS

Health care appears to be the primary driver of prevalent (and possibly incident) infections in MENA, followed by injecting drug use. HCV screening should target the identified modes of exposure. Commitment to prevention should be an integral component of HCV response to achieve HCV elimination by 2030, with focus on strengthening infection control in health care facilities, improving injection safety and blood screening, and expanding harm reduction services for people who inject drugs.