Group A Rotavirus in Sewage Samples from Barcelona and Cairo: Emergence of Unusual Genotypes

Abstract

The presence of rotavirus strains in sewage samples from Cairo, Egypt (November 1998 to October 1999), and Barcelona, Spain (November 1998 to December 2002), was investigated by using a generic molecular detection method based on amplification of a VP6 gene fragment. Overall, 85.7 and 66.9% of the sewage samples from Cairo and Barcelona, respectively, were positive. Positive samples were characterized further, and VP7 and VP4 genotypes were determined. Although 30% of the positive samples from Cairo were G untypeable, the distribution of G types in the positive samples was 69.6% G1, 13% G3, 8.7% G4, and 8.7% G9. The percentage of untypeable samples was much higher for the Barcelona samples (56.5%), and the distribution in the positive samples was 56.4% G1, 31.5% G3, 6% G9, 4% G2, and 2% G5. When the P types were examined, 26.7% of the positive samples from Cairo were untypeable, and the distribution of types in the positive samples was 53. Group A rotaviruses are the leading cause of infantile diarrhea worldwide (24) and are associated with more than 600,000 deaths annually, mainly in developing countries (15). Rotavirus strains may be serotyped on the basis of two outer capsid proteins that are the targets of neutralizing antibodies produced following natural infection; these are glycoprotein VP7, which determines G serotypes, and the protease-sensitive protein VP4, which determines P types (24). Fourteen rotavirus G serotypes, including 10 serotypes that infect humans, have been identified (11). A good correlation between G serotypes and genotypes has been demonstrated (16), and a new genotype of bovine origin has been recognized (30). The correlation is less clear for VP4, since while 13 P serotypes have been detected (11), at least 20 genotypes, including 8 genotypes that infect humans, have been characterized (11). Genotyping studies have indicated that four G-P combinations, P[8]G1, P[4]G2, P[8]G3, and P[8]G4, are common worldwide. Two emerging combinations, P[8]G9 and P[6]G9, are becoming common (1,2,12,15,23). The distribution of rotavirus types may vary between distinct geographic and socioeconomic regions of the world or even between years in a given community. Since the rotavirus serotypes (genotypes) circulating in a given region have a direct influence on the predicted efficiency of a potential vaccine for the region, an examination of the G and P type distribution is necessary.The aim of the present work was to ascertain the G and P type distributions in two different urban areas, Greater Cairo in Egypt from November 1998 to October 1999 and Barcelona in Spain from October 1998 to December 2002, by using sewage samples as the virus sources. Different concentration procedures were used in Cairo and Barcelona. In the first case, viruses from 3 liters of sewage were concentrated in 75 ml of 50 mM glycine buffer with 3% beef extract (Oxoid) by adsorption-elution to negatively charged nitrocellulose membranes (Schleicher and Schuell) (31) and were reconcentrated by organic flocculation in 1 ml of 0.14 N...

Performance Evaluation of a Waste Stabilization Pond in a Rural Area in Egypt

“…Villena et al [33] found that rotaviruses were detected in 85.7% of raw sewage samples in wastewater treatment plants in Cairo. The variation in rotavirus percentage of frequency may be due to increasing of population in Cairo than the population in El-Mofti village.…”

“…The primers VP6-3 5-GCTTTAAAACGAAGTCTTCAAC-3 and VP6-4 5-GGTAAATTACCAATTCCTCCAG-3 were used for amplification of a fragment of the VP6-coding gene corresponding to nucleotides 2-187 for rotavirus with a predicted product size of 190 bp [33] .…”

Diversity of Group A Human Rotavirus Types Circulating over a 4-Year Period in Madrid, Spain

“…In Spain, G5 rotavirus strains have not been detected in human clinical samples. Locally, in Barcelona, Villena et al (45) detected only three G5 strains (2%) in 104 sewage samples. One of these samples was associated with a P [8] type, while the other two could not be associated with any P type but were closely related to porcine strains by phylogenetic analysis.…”

One-year monthly survey of rotavirus, astrovirus and norovirus in three sewage treatment plants in Beijing, China and associated health risk assessment

“…In Bangkok, 25% of the sewage samples were positive for rotavirus using RT-nested PCR (Kittigul et al 2005). A RT-PCR hybridization was used in a study from Barcelona and Cairo, where 66.9% and 85.7% of sewage samples were positive for rotavirus, respectively (Villena et al 2003). A study in France reported a prevalence of rotavirus in raw sewage of 42% (Dubois et al 1997).…”