A molecular study on the prevalence and coinfections of Rotavirus, Norovirus, Astrovirus and Adenovirus in children with gastroenteritis.

BACKGROUND: Viral gastroenteritides are among the causes of higher morbidity and mortality in the childhood period, especially in infants. Although viral-induced diarrheal diseases are important problems in Erzurum, there have been no studies on the molecular prevalence of viral gastroenteritis agents in this region's children. The aim of the prospective study is to determine the molecular prevalence of the most commonly seen viral etiologic agents and their coinfection rates in children under 5 years of age with gastroenteritis in Erzurum, Turkey. METHODS: Stool samples from 375 children between 0 and 5 years of age who suffered from acute diarrhea were investigated for the presence of Rotavirus, Norovirus, Astrovirus and Adenovirus by reverse transcriptase polymerase chain reaction, followed by conventional PCR techniques. The presence of Rotavirus, Norovirus, Astrovirus and Adenovirus in the specimens was detected by amplification of the VP6, RdRp, ORF-1b and Hexon regions, respectively. Stool samples were also investigated non-viral enteropathogens by conventional techniques. RESULTS: At least one viral pathogen was detected in 59.2% of the stool samples. Rotavirus was the most frequently observed agent (32.3%), followed by Norovirus (20.3%), Adenovirus (9.6%) and Astrovirus (5.6%). All specimens were negative for bacterial pathogens. Twenty seven (7.2%) specimens were positive for intestinal helminths and protozoan. A total of 39 coinfection (10.4%) including 38 dual and 1 triple were detected. The most frequent coinfections were observed between Norovirus plus Rotavirus and Norovirus plus Adenovirus. CONCLUSIONS: Single infections or coinfections of the enteropathogenic viruses occur at a significant rate in Erzurum's children. This study draws attention to the necessity of taking account of multiple viral infections in studies on combined vaccines and the treatment of gastroenteritis.

Molecular and restriction fragment length polymorphism analysis of canine parvovirus 2 (CPV-2) in dogs in southeast Anatolia, Turkey.

Canine parvovirus-2 (CPV-2) is the aetiological agent of an infectious viral disease of dogs, characterised by diarrhoea and vomiting. Mutations of the CPV-2 genome have generated new variants circulating worldwide. This article reports the molecular analysis of CPV-2 variants collected in the dog population in southeast Anatolia, Turkey. Twenty blood samples previously taken for the laboratory diagnosis of dogs with suspected parvovirus were screened for CPV-2 by polymerase chain reaction (PCR). Of the 20 samples, 18 tested positive for CPV-2. Partial VP2 gene sequencing and restriction fragment length polymorphism (RFLP) analysis revealed CPV-2a (n = 1), CPV-2b (n = 16) and CPV-2c (n = 1) variants. Phylogenetic analysis based on the partial length VP2 gene showed that CPV-2b (n = 15) variants showed sequences clustering separately in the phylogenetic tree. The CPV-2c sample was phylogenetically related to Chinese strains and Indonesia strain, whereas the CPV-2a sample was phylogenetically related to the Portuguese strain. These results, which are the first to demonstrate the presence of CPV-2c in the dog population of southeast Anatolia, Turkey, indicate that CPV-2a/2b/2c variants co-exist in Turkey's dog population.

Distribution of G (VP7) and P (VP4) genotypes of group A bovine rotaviruses from Turkish calves with diarrhea, 1997-2008.

Group A rotaviruses are major enteric pathogens of calves. In order to investigate the genetic diversity of bovine rotaviruses (BRVs), a collection of 53 BRVs, detected from diarrheic calves from several Turkish geographical areas, between 1997 and 2008 was analyzed by RT-PCR for specificities of the outer capsid proteins VP7 (G type) and VP4 (P type), for the first time. Overall, G6 was the predominant G type, detected in 40/53 samples (75.4%), while P[11] was the predominant P type, detected in 52/53 samples (98.1%). The most common VP7/VP4 combinations were G6P[11] (60.3%) and G10P[11] (24.5%). Mixed infections were identified in 7/53 samples (13.2%). In the VP7 region the G6P[11] viruses were similar to other ones detected worldwide, forming an independent G6 lineage, distantly related to the G6 gene of the vaccine G6P[1] strain NCDV (90.1% amino acid identity), and suggesting that G6P[11] viruses represent a genetically stable BRV strain. The study of G and P type diversity is pivotal to understand the efficacy of the existing rotavirus vaccines and to provide the basis of future prophylaxis tools against rotaviral diarrhea of calves.