Nadia Teleb

The epidemiology of rotavirus diarrhea in countries in the Eastern Mediterranean Region.

OBJECTIVE Rotavirus is the leading cause of severe diarrhea among children worldwide, killing approximately 600,000 children annually, including 64,800 in the Eastern Mediterranean Region. Safe, effective rotavirus vaccines will be available soon, and accurate disease burden data will be needed to assess the burden of rotavirus and the value of new vaccines and monitor vaccine program impact. METHODS To identify epidemiologic studies in which rotavirus diagnostics were applied to children with acute gastroenteritis, we performed a systematic literature review. We selected studies that met 4 criteria and extracted rotavirus data on prevalence estimates, strain identification, age distribution of patients, and seasonal trends. RESULTS Of the 63 published studies with some rotavirus detection data, 29 met inclusion criteria. Among patients with diarrhea, rotavirus was detected in 40% of inpatients and 23% of outpatients. By 3 years of age, 75% of children experienced a documented rotavirus infection. Circulation of rotavirus occurred year-round, and no clear relationship between the timing of the rotavirus peak with either season or latitude was observed. Comparison of country-specific rotavirus detection rates indicated that the proportion of hospitalizations for rotavirus infection increased with income. CONCLUSION This systematic review of studies of rotavirus diarrhea among children in the countries of the Eastern Mediterranean Region documents that rotavirus is one of the most significant causes of childhood diarrhea in the region. The findings of this review will be used to establish sentinel hospital surveillance in these countries, estimate disease burden, and characterize its epidemiology using common protocols and diagnostics.

Sentinel Hospital-Based Surveillance of Rotavirus Diarrhea in Iran

BACKGROUND Rotavirus is the most common causes of severe, acute diarrhea during childhood and is an important cause of morbidity and mortality in developing countries. We established active hospital-based surveillance of childhood diarrhea to assess the scope of severe rotavirus disease in Iran. METHODS From May 2006 through April 2007, prospective surveillance of rotavirus diarrhea among children aged <5 years was conducted in 5 sentinel hospitals in Iran. Stool samples were tested for rotavirus using a commercially available enzyme immunoassay, and rotavirus-positive samples were genotyped using reverse-transcriptase polymerase chain reaction. RESULTS Of 2198 children admitted to the hospital for acute gastroenteritis, 1298 (59.1%) had stool samples test positive for rotavirus by enzyme immunoassay. Of the rotavirus episodes, 85% occurred during the first 2 years of life, with the peak prevalence of severe rotavirus disease occurring from September through January. Among the 110 rotavirus-positive samples that were genotyped, G4P[8] was the most commonly detected rotavirus genotype (30.9% of strains). Other commonly detected genotypes included P[8] with G nontypeable (21.8%), G4 with P nontypeable (13.6%), G1[P8] (10.9%), and G2[P4] (5.5%). CONCLUSIONS Rotavirus is the most common cause of severe diarrhea in Iran, which indicates that safe and effective rotavirus vaccination in Iran is a public health priority.

A global review of national influenza immunization policies: Analysis of the 2014 WHO/UNICEF Joint Reporting Form on immunization.

Introduction The WHO recommends annual influenza vaccination to prevent influenza illness in high-risk groups. Little is known about national influenza immunization policies globally. Material and Methods The 2014 WHO/UNICEF Joint Reporting Form (JRF) on Immunization was adapted to capture data on influenza immunization policies. We combined this dataset with additional JRF information on new vaccine introductions and strength of immunization programmes, as well as publicly available data on country economic status. Data from countries that did not complete the JRF were sought through additional sources. We described data on country influenza immunization policies and used bivariate analyses to identify factors associated with having such policies. Results Of 194 WHO Member States, 115 (59%) reported having a national influenza immunization policy in 2014. Among countries with a national policy, programmes target specific WHO-defined risk groups, including pregnant women (42%), young children (28%), adults with chronic illnesses (46%), the elderly (45%), and health care workers (47%). The Americas, Europe, and Western Pacific were the WHO regions that had the highest percentages of countries reporting that they had national influenza immunization policies. Compared to countries without policies, countries with policies were significantly more likely to have the following characteristics: to be high or upper middle income (p < 0.0001); to have introduced birth dose hepatitis B virus vaccine (p < 0.0001), pneumococcal conjugate vaccine (p = 0.032), or human papilloma virus vaccine (p = 0.002); to have achieved global goals for diphtheria-tetanus-pertussis vaccine coverage (p < 0.0001); and to have a functioning National Immunization Technical Advisory Group (p < 0.0001). Conclusions The 2014 revision of the JRF permitted a global assessment of national influenza immunization policies. The 59% of countries reporting that they had policies are wealthier, use more new or under-utilized vaccines, and have stronger immunization systems. Addressing disparities in public health resources and strengthening immunization systems may facilitate influenza vaccine introduction and use.

Considerations for Introduction of a Rotavirus Vaccine in Oman: Rotavirus Disease and Economic Burden

Rotavirus is the most common cause of fatal childhood diarrhea worldwide. We provide the first estimates of the health care and economic burden of severe rotavirus disease in Oman. We conducted active, hospital-based surveillance of rotavirus disease at 11 regional public hospitals in Oman, using the guidelines suggested by the generic World Health Organization protocol. From July 2006 through June 2008, all children aged <5 years who were hospitalized for acute gastroenteritis were enrolled in the surveillance program, and their stool samples were tested for rotavirus using a commercially available enzyme immunoassay (ID EIA Rotavirus Test; Dako Diagnostics). Rotavirus was detected in samples from 1712 (49%) of 3470 children. These children were hospitalized for a median of 3 days for severe diarrhea. A marked seasonal peak was evident with a majority of the cases occurring from December through May. Of the rotavirus cases, 69% occurred in children aged 6-17 months. We identified a diverse strain pattern in Oman, with G2 (37%), G1 (38%), and G9 (11%) accounting for most of typeable strains. By our burden estimates, the Omani government spends an estimated US

Epidemiology of rotavirus gastroenteritis among children <5 years of age in Morocco during 1 year of sentinel hospital surveillance, June 2006-May 2007.

791,817 and US

Characterization of human rotaviruses circulating in Iraq in 2008: Atypical G8 and high prevalence of P[6] strains

1.8 million annually to treat rotavirus-associated diarrhea in the outpatient and hospital settings, respectively. A rotavirus vaccination program might substantially reduce the burden of severe diarrhea among children in Oman.

Baseline burden of rotavirus disease in Sudan to monitor the impact of vaccination.

BACKGROUND In anticipation of vaccine introduction, we assessed the epidemiology, burden, and genotype of infecting strains of rotavirus disease among Moroccan children hospitalized for acute gastroenteritis. METHODS From June 2006 through May 2007, 345 children <5 years of age who had acute gastroenteritis and were admitted to 4 sentinel hospitals in different regions of Morocco were enrolled in this surveillance study, and stool specimens were tested for the presence of rotavirus with use of enzyme immunoassay. RNA from positive samples was genotyped by reverse-transcriptase polymerase chain reaction. RESULTS Overall, 314 children had complete data available, and among these, 138 (44%) tested positive for rotavirus. Rotavirus infection was most common among children <24 months of age (95% of all hospitalizations for rotavirus infection). Rotavirus infection was detected year-round at all 4 sites but was most prevalent from September through January. Genotype analysis demonstrated that 30.6% of samples were G1[P8], 26% were G9[P8], 7.5% were G2[P6], 3.7% were G1[P6], and 0.7% were G2[P8]. Nucleotide sequencing analysis of G- or P-untypeable strains showed that 4.5% were G9[P8], 2.2% were G1[8], 2.2% were G2[P6], and 1.5% were G2[P4]. A high frequency of mixed infection (21%) was found, of which G1G2[P8] accounted for the majority (16.4%). CONCLUSIONS Rotavirus was responsible for 44% of all hospitalizations for diarrhea among young children at these 4 separate sites in Morocco. These data will help inform a decision on the introduction of rotavirus vaccine in Morocco. Continued and extended surveillance in Morocco will be important to monitor changes in the epidemiology of rotavirus disease and the impact of vaccination after introduction.

Monitoring of rotavirus vaccination in Morocco: establishing the baseline burden of rotavirus disease.

Fecal samples from 976 children with gastroenteritis were collected and analyzed for group A rotavirus (RVA), in three different cities in Iraq between January 2008 and December 2008. RVA antigen was detected in 394 (40%) of the samples, and 98 samples were available for further genotype analyses using multiplex RT-PCR and sequence analyses for untypeable strains. The G/P-genotype combination was determined for 69 samples, and 19, 2 and 8 samples remained P-untypeable, G-untypeable and G/P-untypeable (UT), respectively. The most prevalent genotype was G2 (40%, 39/98) most often associated with P[6]. G1 was the second most common genotype (16%, 16/98) mainly associated with P[8] and P[UT]. G3, G4 and G9 were detected at a lower prevalence (3%, 11%, 3%, respectively), mainly associated with P[6]. Surprisingly, five G8P[6], and seven G12 RVA strains in combination with P[6] and P[8] were also detected for the first time in Iraq. Overall, a striking high prevalence of 47% of the analyzed samples possessed the P[6] genotype (65% of the P-typed RVA strains). Atypical genotype combinations such as G1P[4], G1P[6], G2P[8] or strains with mixed G-types were detected sporadically. The detection of unusual G8P[6] RVA strains prompted us to further analyze the NSP2, NSP3, NSP4 and NSP5 gene segments of three selected G8P[6] strains, resulting in their designation to the N2, T2, E2 and H2 genotypes, respectively. The VP7, VP4, NSP2, NSP3 and NSP5 gene segments clustered closely with common human RVA strains, whereas the NSP4 gene sequences were found to cluster with animal derived RVA strains, suggesting a potential reassortment event. The high prevalence of RVA strains with the G8, G12 and P[6] genotypes in combination with a DS-1-like genotype constellation in Iraq, needs to be monitored closely as these RVA strains might challenge the effectiveness of current RVA vaccines.

Vaccination with Haemophilus influenzae type b conjugate vaccine reduces bacterial meningitis in Morocco

Background: In 2011, Sudan became the first low-income country in Africa to introduce a rotavirus vaccine. Prevaccine baseline data on rotavirus disease burden are crucial for monitoring the impact of this new vaccine program. Methods: We conducted active, hospital-based surveillance for rotavirus disease at 8 regional public hospitals in Sudan using a standard protocol recommended by the World Health Organization for 2 full years immediately preceding vaccine introduction. Cases were children <5 years hospitalized with gastroenteritis, defined as acute onset of 3 or more loose stools or 2 or more episodes of vomiting in a 24-hour period. Stool specimens from cases were tested for rotavirus using a commercially available assay. Results: From June 2009 to May 2011, rotavirus was detected in 3985 (36%) of 10,953 children hospitalized for gastroenteritis, with detection rates ranging from 25% to 48% at the 8 hospitals. Approximately 61% of the rotavirus hospitalizations occurred before 1 year of age and most (91%) occurred before 2 years of age. Rotavirus was detected year-round in Sudan with peaks during March to May and November to December. Applying rotavirus prevalence to national estimates of diarrhea events, we calculated 9800 deaths, 22,800 hospitalizations and 55,400 outpatient visits related to rotavirus per year among children <5 years of age in Sudan. Conclusions: The high burden of rotavirus disease in Sudan indicates that the recently implemented vaccination program should substantially improve child health in Sudan. This nationwide rotavirus surveillance system will be an important platform for assessing the benefits and value of rotavirus vaccine in a developing country setting.

Bacterial Meningitis Surveillance in the Eastern Mediterranean Region, 2005-2010: Successes and Challenges of a Regional Network

BACKGROUND Rotavirus is a leading cause of childhood morbidity and mortality worldwide. Clinical trials for two rotavirus vaccines recommended by the WHO for global use since 2009 have successfully demonstrated the safety and efficacy of these vaccines in a wide range of countries. To control the burden of severe and fatal diarrheal disease, the Ministry of Health of Morocco introduced the single strain rotavirus vaccine into their national immunization program in 2010. METHODS We employed a standard WHO case definition to identify children under 5 hospitalized with AGE at four hospitals from June 2006 to May 2010 to establish baseline burden of rotavirus disease before introduction of vaccine. Stool samples were collected and tested for rotavirus using a standard enzyme immunoassay. RESULTS Overall, 40% (741 of 1841) of the children hospitalized with AGE tested positive for rotavirus, making it the single most common cause of severe gastroenteritis among children in Morocco. Applying this prevalence to the estimates of diarrheal hospitalizations and deaths in Morocco, we estimate that rotavirus annually causes 19,646 hospitalizations and 1604 deaths in children under 5 years of age. DISCUSSION On the basis of these surveillance data, we estimate that 1 in 389 Moroccan children died and 1 in 32 was hospitalized due to rotavirus before their fifth birthday. A considerable proportion of these deaths and hospitalizations should be preventable through vaccination, and the 4 years of stable prevaccine surveillance in Morocco will be a tremendously useful platform for assessing potential changes in the epidemiology of rotavirus disease and measuring impact of the new rotavirus vaccine program in Morocco.