The epidemiology of Norovirus in the Middle East and North Africa (MENA) region: a systematic review

Abstract

Norovirus (NoV) is considered the second leading cause of viral acute gastroenteritis (AGE). To our knowledge, there are no systematic reviews assessing the role of NoV in AGE in the Middle East and North Africa (MENA) region. Consequently, we conducted an extensive systematic literature review on articles studying NoV in the 24 countries of the MENA region during the past 15 years (2000-2015). The methods and reporting were set according to the 2015 PRISMA-P and based on the elements from the international prospective register of systematic reviews (PROSPERO). We retrieved 38 studies meeting our predefined inclusion criteria and were used to extract full data. Studies reporting on NoV were conducted in 15 out of the 24 countries of the region. The reported NoV infection rates in MENA countries ranged between 0.82% and 36.84%. The majority of studies were clinical observational studies assessing NoV rates mainly among children. Participants were recruited from in- and outpatient clinics. NoV infection was reported all year round with with peaks observed mainly during cold months. GII.4 was the predominant genotype detected in stool of participants as reported by 16 out of 25 studies (64%). Overall, there is an increasing recognition of NoV as an important causative agent of AGE across all age groups in the MENA region. Further studies are needed to assess the national and the regional burden of NoV among different age groups, its molecular diversity and seasonal variability.

Epidemiological, Molecular, and Clinical Features of Norovirus Infections among Pediatric Patients in Qatar

“…Our analysis revealed the dominance of the GII genogroup, specifically the GII.4 (62.2%) genotype, which is consistent with previous reports from MENA region [23]. This observation is also in agreement with the global distribution of NoV, where GII.4 represents 68% of reported NoV cases worldwide [47].…”

“…NoV GII.4 was found to be the predominant genotype among all age groups in the MENA region. According to the available data, NoV seems to peak in the winter season in ~40% of the MENA countries (Egypt, Morocco, Tunisia, and Turkey), while it still circulates during the fall and summer in 25% of the countries (Egypt, Libya, Morocco, Tunisia, and Turkey) [23]. This differential seasonality is affected by variations in environmental conditions, temperature cycles, as well as winds and humidity rain patterns [24].…”

Norovirus Infections and Disease in Lower‐Middleand Low‐Income Countries, 1997–2018

“…In the current review, norovirus was detected in LMIC in 15% (95% CI 15–16) of symptomatic cases and 8% (95% CI 7–9) of healthy controls. The percentage of norovirus detected overall in symptomatic cases correlates well with previous estimates in LMIC (15%; 95% CI 13–18) [19], in Latin America (15%; 95% CI 13–18) [15], and in MENA countries (15.3% median) [18]. The asymptomatic detection rate of 8% is comparable to the previous LMIC (5%; 95% CI 3–10) [19] and Latin American (8%; 95% CI 4–13) estimates [15].…”

“…The majority of these deaths occur in low-resource countries. Several systematic reviews have reported the prevalence of the norovirus in specific regions such as Latin America (15%; 95% CI 13–18) [15,16], China (19.8%–21.0%) [17], the Middle East and North Africa (MENA) (15.3%—median infection rate) [18], and 46 low-resource (developing) countries (17%; 95% CI 15–18) [19].…”

Progress on norovirus vaccine research: public health considerations and future directions

“…Children under 2 years old had higher norovirus prevalence (18%) than children up to 5 years old (12%) [23]. A review of 38 studies from 15 countries in the Middle East and Northern Africa (MENA) region from 2000 to 2015 reported a median norovirus prevalence of 15% among AGE patients (range 0.8–37% by country) [25]. A systematic review in Latin America found an overall pooled prevalence of 15% (95% CI 13%−18%) among AGE cases [26].…”