http://hdl.handle.net/10500/3972 2013-05-26T04:23:39Z 2013-05-26T04:23:39Z Al Baqlani, Said Dewar, John Pearson, Lindsey Mothokoa, Charles Rupa, Varghese Al Awaidy, Salah Peenze, Ina Al Busaidy, Suleiman Steele, Duncan A. Al Lawati, Zainab http://hdl.handle.net/10500/3967 2012-08-08T12:00:26Z 2010-09-01T00:00:00Z

Molecular Characterization of Rotavirus Strains Circulating in Oman in 2005 Al Baqlani, Said; Dewar, John; Pearson, Lindsey; Mothokoa, Charles; Rupa, Varghese; Al Awaidy, Salah; Peenze, Ina; Al Busaidy, Suleiman; Steele, Duncan A.; Al Lawati, Zainab Limited genotyping data are available for rotavirus strains in the Middle East. In this study, we investigated the molecular epidemiology of human rotavirus strains circulating in the Sultanate of Oman during 2005. Rotavirus was detected in 178 (57.4%) of 310 of the diarrheal stools of young children under 5 years admitted to hospitals and outpatients clinics. Polyacrylamide gel electrophoresis demonstrated the cocirculation of 8 strains, although 2 strains predominated across the Sultanate. Genotyping revealed the presence of human rotavirus strains of types G1P[8], G2P[4], and G3P[8]. Several strains exhibited unusual combinations of G and P genotypes and RNA electropherotypes, indicating the likelihood of natural reassortment events occurring with a high frequency. In addition, the unusual P[10] genotype was identified among the rotavirus strains, in combination with the G1 type.

2010-09-01T00:00:00Z Aminu, M. Ahmad, A.A. Steele, A.D. Page, N.A. Dewar, J. Umoh, J.U. http://hdl.handle.net/10500/3966 2012-08-08T12:37:54Z 2010-09-01T00:00:00Z

Diversity of Rotavirus VP7 and VP4 Genotypes in Northwestern Nigeria Aminu, M.; Ahmad, A.A.; Steele, A.D.; Page, N.A.; Dewar, J.; Umoh, J.U. Background: Nigeria has recently been ranked third among the 10 countries with the greatest number of rotavirus disease–associated deaths per year. Estimates attribute up to 33,000 deaths annually to rotavirus disease in Nigerian children under 5 years old. Although the introduction of the new oral, live attenuated rotavirus vaccines may not occur for another 4–6 years in developing countries, background data on burden of disease, cost of rotavirus disease, and characterization of circulating strains is required to hasten this introduction to children who would clearly benefit from the intervention. Methods: Between July 2002 and July 2004, fecal specimens were collected from 869 infants and young children under 5 years of age presenting with diarrhea in Kaduna, Kebbi, Sokoto, and Zamfara states in northwestern Nigeria. In addition, 194 control specimens were also collected from children matched for age. Specimens were screened for the presence of rotavirus antigens. Rotavirus-positive specimens were further analyzed to determine electropherotype,subgroup specificity, and G and P genotypes. Results: Rotavirus was detected in 18% of children with diarrhea and 7.2% of the age-matched case control subjects. The highest rotavirus burden was detected in children aged undre 6 months. The majority of the rotaviruspositive specimens revealed viruses of long electropherotypes, subgroup II specificity, and G1P[8] genotypes. Furthermore, more than a quarter of specimens (37%) displayed mixed G and P genotypes, and almost a third could not be genotyped. Conclusions. The high numbers of mixed rotavirus infections highlight the multitude of enteric pathogens to which children in African countries are exposed. Data on circulating rotavirus strains serve to inform African government officials to the serious health threat posed by rotavirus in their respective countries and to document the diversity of strains before vaccine introduction.

2010-09-01T00:00:00Z Mapaseka, Seheri Luyanda Van der Merwe, Lize Tumbo, John Bos, Pieter Duncan Steele, A. Dewar Barr, John Geyer, Annelise Zweygarth, Monika Esona, Mathew Dioh Sommerfelt, Halvor http://hdl.handle.net/10500/3934 2012-08-15T05:58:45Z 2010-09-01T00:00:00Z

Prospective hospital-based surveillance to estimate rotavirus disease burden in the Gauteng and North West Province of South Africa during 2003–2005 Mapaseka, Seheri Luyanda; Van der Merwe, Lize; Tumbo, John; Bos, Pieter; Duncan Steele, A.; Dewar Barr, John; Geyer, Annelise; Zweygarth, Monika; Esona, Mathew Dioh; Sommerfelt, Halvor Background : Rotavirus is considered to be the most common cause of serious acute dehydrating diarrhea worldwide. However, there is a scarcity of information on rotavirus disease burden in sub-Saharan Africa. Methods : We conducted prospective, hospital-based surveillance for rotavirus diarrhea among children 5 years of age at the tertiary care Dr. George Mukhari Hospital (DGM) and at the Brits district Hospital (BH) in the Gauteng and North West Provinces in South Africa; we estimated that up to 80% of children under 5 years of age in their catchment areas who are hospitalized for diarrhea are admitted to one of these hospitals. Results: At DGM, 2553 children under 5 years of age were admitted for diarrhea from January 2003 through December 2005, and 852 children under 5 years of age were treated for diarrhea at BH during 2004–2005. We examined stool specimens from 450 children (53%) at BH and from 1870 children (73%) admitted to DGM. An estimated 22.8% (95% confidence interval [CI], 21.2%–24.5%) of the children hospitalized with diarrhea at DGM were rotavirus positive, and the corresponding figure at BH was 18.2% (95% CI, 14.9%–22.1%). Among children under 5 years of age admitted to DGM for any reason, an estimated 5.5% (95% CI, 5.1%–6.0%) had rotavirus diarrhea. Our incidence estimates suggest that 1 in 43–62 children in the area is likely to be hospitalized with rotavirus. diarrhea by 2 years of age. Conclusions: Prevention of serious rotavirus illness by vaccination will substantially reduce not only the disease. burden among young children but also the case load in South African health care facilities. Present affiliations : Life and Consumer Sciences, University of South Africa (Florida Campus), Johannesburg, South Africa (J.B.D.); Gastroenteritis and Respiratory Viruses Laboratory Branch, Division of Viral Diseases, National Center for Immunizations and Respiratory Disease, Centers for Disease Control and Prevention, Atlanta, Georgia (M.D.E.); and Vaccines and Immunization, PATH, Seattle, Washington (A.D.S.).

2010-09-01T00:00:00Z Esona, Mathew Dioh Kerin, Tara Peenze, Ina Nicola Page, James Nyangao Akran Agbaya, Veronigue Aminu, Maryam Sebunya,Theresia Glass, Roger Steele, Duncan Armah, George Page, Nicola Nyangao, James Trabelsi, Abdelhalim Gentsch, Jon http://hdl.handle.net/10500/3933 2012-08-15T05:57:42Z 2010-09-01T00:00:00Z

Determination of the G and P types of previously nontypeable rotavirus strains from the African notavirus network, 1996–2004 : identification of unusual G types Esona, Mathew Dioh; Kerin, Tara; Peenze, Ina; Nicola Page, James Nyangao; Akran Agbaya, Veronigue; Aminu, Maryam; Sebunya,Theresia; Glass, Roger; Steele, Duncan; Armah, George; Page, Nicola; Nyangao, James; Trabelsi, Abdelhalim; Gentsch, Jon A total of 215 nontypeable rotavirus samples collected from children 5 years of age by members of the African Rotavirus Network were characterized using reverse-transcription polymerase chain reaction analysis and sequencing. The most predominant strain identified was P[8]G1 (46.9%). Genotypes P[8]G10, P[8]G8, P[6]G8, and P[7]G5 were also detected at frequencies varying from 0.5% to 2.3%. This study suggests that reassortment of unusual G types into a background of globally common genotype P[8] strains may be a major mechanism of generating rotavirus diversity. Nucleotide substitutions at the P[8], P[6], and G1 primer binding sites accounted for the failure to type these strains initially. Hence, these findings highlight the need for regular evaluation of rotavirus genotyping methods. Acknowledgments: The postdoctoral fellowship of Dr Esona was provided through the Rotavirus Vaccine Program, a collaboration between the Program for Appropriate Technology in Health, the World Health Organization, and the Centers for Disease Control and Prevention. Our sincere thanks also go to all the staff of the Medical Research Council Diarrhoeal Pathogens Research Unit, University of Limpopo, and the Gastroenteritis and Respiratory Viruses Laboratory Branch at the Centers for Disease Control and revention,Atlanta, for their immense assistance.

2010-09-01T00:00:00Z