6.1. Search Results and Study Selection
A total of 563 records were identified through the electronic search that reported HCV genotypes and subtypes from EMRO countries. Of these records, 349 duplicates were found and excluded. Based on screening of the remaining titles and abstracts, 158 potentially relevant manuscripts were retrieved and included for full full-text examination. We only included studies with primary data in our analysis; publications reporting the same data were considered duplicates and excluded. In addition, we excluded papers with unclear and ambiguous data. Screening of full-text studies identified 134 eligible studies for inclusion in the analysis (
Figure 1).
Flowchart of Systematic Literature Search and Article Selection
According to what we identified, no data were available from Djibouti, Oman, Somalia, and Yemen concerning prevalence of HCV genotypes and subtypes. Furthermore, only 1 study was found from Afghanistan, Palestine, Qatar, Syria, and Sudan. Finally, we found 49 studies from Iran involving 26058 subjects, 34 studies including 50407 subjects from Pakistan, 10 studies with 5270 subjects from Egypt, 6 studies with 2116 subjects from Saudi Arabia, 6 studies with 11825 subjects from Tunisia, 5 studies with 594 subjects from Iraq, 5 studies with 1680 subjects from Morocco, 3 studies with 374 subjects from Lebanon, 3 studies with 14641 subjects from Jordan, 2 studies with 264 subjects from Bahrain, 2 studies with 185 subjects from Kuwait, 2 studies with 2131 subjects from Libya, and 2 studies including 191 subjects from the United Arab Emirates. Populations investigated to estimate the prevalence of HCV genotypes and subtypes were mainly chronic-HCV-infected patients, such as people with thalassemia, hemophiliacs, hemodialysis patients, and injecting drug users. In addition, a few studies included general population groups, such as blood donors, healthy volunteers, and pregnant women. Characteristics of the included patients and the studies from the EMRO countries were shown in Appendix 1.
6.2. Prevalence of HCV Genotypes and Subtypes in EMRO Countries
Based on our results, genotype distribution of HCV takes diverse patterns in EMRO countries (
Figure 2). According to the random-effect model, the estimated pooled prevalence of HCV genotypes and subtypes in each of the EMRO countries is listed below.
Distribution of Hepatitis C Virus Genotypes and Subtypes in EMRO Countries
In Pakistan, genotype 3 was the predominant genotype with a rate of 67% (95% CI, 62 - 71); followed by genotype 1, 8% (95% CI, 6 - 10). Subtype 3a was the most common subtype with a rate of 56% (95% CI, 49 - 62); followed by subtype 3b, 10% (95% CI, 7 - 12). Appendix 2 provides forest plots depicting pooled summary estimates of the prevalence of HCV genotypes and subtypes in Pakistan. In Iran, genotype 1 was the most prevalent genotype with a rate of 54% (95% CI, 51 - 58); followed by genotype 3, 36% (95% CI, 32 - 39). Subtype 1a was the predominant subtype with a rate of 42% (95% CI, 39 - 46); followed by subtype 3a, 35% (95% CI, 31 - 38); and subtype 1b, 11% (95% CI, 10 - 13). Appendix 3 provides forest plots depicting pooled summary estimates of the prevalence of HCV genotypes and subtypes in Iran. A study in 113 HCV-RNA-positive injection drug users in Afghanistan showed subtype 3a as dominant with a rate of 39% (95% CI, 30 - 48); followed by subtype 1a, 22% (95% CI, 15 - 30).
Pooled summary estimates of the prevalence of HCV genotypes and subtypes in north African countries, including Egypt, Tunisia, Morocco, Libya, and Sudan, were shown in Appendix 4. In Tunisia, genotype 1 was the predominant genotype with a rate of 75% (95% CI, 57 - 94); followed by genotype 4, 22% (95% CI, 5 - 39). Subtype 1b was the most common subtype in Tunisia with a rate of 69% (95% CI, 50 - 88). In Egypt, genotype 4 was the most common genotype with a rate of 69% (95% CI, 36 - 100); followed by genotype 1, 5% (95% CI, 3 - 7). Subtype 4a was the most prevalent subtype with a rate of 59% (95% CI, 35 - 83); followed by subtype 1b, 3% (95% CI, 1 - 5). In Libya, genotype 4 and genotype 1 account for 32% (95% CI, 26 - 39); and 32% (95% CI, 30 - 34) of the pooled estimate of the HCV genotype rate, respectively, and were the predominant genotypes. There was no data about HCV subtypes in published studies from Libya. In Morocco, genotype 1 was the most prevalent genotype with a rate of 55% (95% CI, 41 - 69); followed by genotype 2, 26% (95% CI, 17 - 34). Subtype 1b was the most common subtype in Morocco with a rate of 32% (95% CI, 7 - 56). A study in 176 Sudanese patients with hepatosplenic schistosomiasis revealed genotype 4 as a major HCV genotype.
Pooled summary estimates of the prevalence of HCV genotypes and subtypes in Middle East Arab countries, including Saudi Arabia, Iraq, Lebanon, Jordan, Bahrain, Kuwait, the United Arab Emirates, Palestinian, Qatar, and Syria, were shown in Appendix 5. In Jordan, genotype 1 and genotype 4 account for 52% (95% CI, 11 - 94); and 52% (95% CI, 24 - 79) of the pooled estimate of the HCV genotype rate, respectively, and were the predominant genotypes. In Saudi Arabia, genotype 4 was the most prevalent genotype with a rate of 65% (95% CI, 59 - 72); followed by genotype 1, 23% (95% CI, 15 - 30). There was no data about HCV subtypes in published studies from Saudi Arabia. In Iraq, genotype 1 was the most common genotype with a rate of 45% (95% CI, 23 - 67); followed by genotype 4, 32% (95% CI, 17 - 48). Subtype 1b was the predominant subtype with a rate of 23% (95% CI, 12 - 35); followed by subtype 1a, 15% (95% CI, 2 - 27). In Lebanon, genotype 1 was the most common genotype with a rate of 37% (95% CI, 26 - 47); followed by genotype 4, 33% (95% CI, 18 - 47). The most common HCV genotype in Bahrain was genotype 1 with an estimated pooled prevalence of 37% (95% CI, 30 - 43). Genotype 4 was the most common genotype in Kuwait with a rate of 43% (95% CI, 33 - 52); followed by genotype 1, 28% (95% CI, 21 - 34). The predominant genotype in the United Arab Emirates was genotype 1 with a rate of 38% (95% CI, 16 - 60); followed by genotype 4, 30% (95% CI, 1 - 61). A study among 92 Palestinian chronic-HCV-infected patients reported genotype 4 as a predominant genotype with a rate of 64% (95% CI, 54 - 74); followed by genotype 1, 28% (95% CI, 19 - 37). An investigation into 400 chronic-HCV-infected patients in Qatar revealed genotype 4 as the most common genotype with a rate of 64% (95% CI, 59 - 69); followed by genotype 1, 20% (95% CI, 15 - 24). A comprehensive study among 636 consecutive HCV-infected patients referred to eight major medical centers in Syria showed genotype 4 as the most prevalent genotype with a rate of 59% (95% CI, 55 - 63); followed by genotype 1, 28% (95% CI, 25 - 32); and genotype 5, 10% (95% CI, 8 - 12).