Epidemiology of echinococcosis in Iran: a systematic review and meta-analysis

Abstract

BackgroundEchinococcosis is a zoonotic disease caused by the larval stages of taeniid cestodes of the genus Echinococcus. The two major types of infection in humans are cystic echinococcosis (CE) or hydatidosis and alveolar echinococcosis (AE). It is endemic in some parts of the world, such as the Middle East, with Iran being a part of it. This systematic review and meta-analysis were conducted to determine the prevalence of CE and AE echinococcosis and their epidemiological and clinical aspects in Iran.MethodsElectronic databases, including MEDLINE (via PubMed), SCOPUS, Web of Science, SID and Mag Iran (two Persian scientific search engines) were searched from 1 January 1990 to 8 August 2017. The prevalence of CE and AE echinococcosis was estimated using the random effects meta-analysis. Heterogeneity was evaluated by subgroup analysis. Data were analyzed by STATA version 12.ResultsOf the 2051 records identified in the mentioned electronic databases, Seventy-eight articles met our eligibility criteria, with a total of 214124individuals. The meta-analysis was performed on only 37 out of 78 included studies. The pooled prevalence of CE and AE in Iran was 5% [95% confidence interval )CI(: 3-6%] and 2% [95% CI: 0-5%], respectively. Subgroup meta-analysis revealed that the prevalence of CE was significantly higher in North [9%, 95% CI: 4-18%] and West of Iran [6%, 95% CI: 3-11%], patients younger than 40 years of age [7%, 95% CI: 4-12%], villagers and nomads [6%, 95% CI: 2-12%], and studies that used the combination of serological, clinical, and imaging diagnostic methods [7%, 95% CI: 5-9%]. There were no significant differences between the prevalence of CE among low and high-quality studies. Housewives were the most affected group by hydatidosis (n=24/77, 31%), followed by illiterate people (n=11/77, 14%) and farmers (n= 9/77, 12%). Liver [55%, 95% CI: 46-65%] and lung [28%, 95% CI, 22-35%] were the most common sites of cyst formation.ConclusionsGiven to the importance of echinococcosis on human health and domestic animals industry, it is necessary to implement monitoring and control measures in this regard.

An Update on the Epidemiological Features of Imported Schistosomiasis and Cystic Echinococcosis in Kuwait, 2010–2018

“…The seroprevalence of CE in our study was similar in younger versus older subjects and male ( n = 33; 3.3%) versus female ( n = 24; 2.4%) patients ( p > 0.05). Although similar findings were reported from a high-risk area in Jordan [23], a recent systematic review and meta-analysis of 37 studies from Iran showed higher prevalence of CE in patients younger than 40 years of age [21]. A study from Iraq has shown that CE affected more females (61.2%) than males (38.8%) and more cases were reported in the age-group of 21–30 years than in other age-groups [24].…”

“…A more recent systematic review and meta-analysis from the Middle Eastern countries has also reported CE seroprevalence rates of 7.4 and 10.7% in the general population and in high-risk individuals, respectively [20]. Similarly, a systematic review and meta-analysis had reported higher pooled prevalence of CE and alveolar echinococcosis in Iran at 5 and 2%, respectively [21]. In addition, it also detected a significant association of CE with keeping dogs as pets or contact with dogs ( p = 0.022) as well as consumption of raw or undercooked vegetables ( p < 0.001) [22].…”

Assessment of Knowledge, Attitudes and Practices Relating to Parasitic Diseases and Anthelmintic Resistance Among Livestock Farmers in Hamedan, Iran

“…However, the most important zoonotic disease in Iran with an estimated annual monetary burden of US$232.3 million is cystic echinococcosis (23). The weighted prevalence of hydatidosis in animal and human intermediate hosts reach 15.6 and 5%, respectively (24,25). Livestock in Iran are mainly slaughtered in industrial abattoirs with standardized protocols for condemnation of infected organs, but farmers in remote areas slaughter their own sheep and goats.…”

Transcriptomic Features of Echinococcus granulosus Protoscolex during the Encystation Process

“…Cystic echinococcosis (CE), also known as hydatid disease, is a chronic neglected zoonotic disease caused by the larvae of Echinococcus granulosus that endangers human health and leads to huge economic losses in animal husbandry [1]. Recent epidemiological studies have shown that at least 270 million people (58% of the total population) are at risk of CE in Central Asia, including Mongolia, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, Uzbekistan, Iran, Pakistan, and western China [2,3]. The larval stage (hydatid cyst) of E. granulosus is characterized by long-term growth in the internal organs of humans and other intermediate hosts, especially in the liver and lungs [4].…”