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- Hellmér, Maria, et al.
(författare)
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Detection of Pathogenic Viruses in Sewage Provided Early Warnings of Hepatitis A Virus and Norovirus Outbreaks
- 2014
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Ingår i: Applied and Environmental Microbiology. - : American Society for Microbiology. - 0099-2240 .- 1098-5336. ; 80:21, s. 6771-6781
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Tidskriftsartikel (refereegranskat)abstract
- Most persons infected with enterically transmitted viruses shed large amounts of virus in feces for days or weeks, both before and after onset of symptoms. Therefore, viruses causing gastroenteritis may be detected in wastewater, even if only a few persons are infected. In this study, the presence of eight pathogenic viruses (norovirus, astrovirus, rotavirus, adenovirus, Aichi virus, parechovirus, hepatitis A virus [HAV], and hepatitis E virus) was investigated in sewage to explore whether their identification could be used as an early warning of outbreaks. Samples of the untreated sewage were collected in proportion to flow at Ryaverket, Gothenburg, Sweden. Daily samples collected during every second week between January and May 2013 were pooled and analyzed for detection of viruses by concentration through adsorption to milk proteins and PCR. The largest amount of noroviruses was detected in sewage 2 to 3 weeks before most patients were diagnosed with this infection in Gothenburg. The other viruses were detected at lower levels. HAV was detected between weeks 5 and 13, and partial sequencing of the structural VP1protein identified three different strains. Two strains were involved in an ongoing outbreak in Scandinavia and were also identified in samples from patients with acute hepatitis A in Gothenburg during spring of 2013. The third strain was unique and was not detected in any patient sample. The method used may thus be a tool to detect incipient outbreaks of these viruses and provide early warning before the causative pathogens have been recognized in health care.
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| 4. |
- Samimi-Rad, K., et al.
(författare)
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Patient-to-Patient Transmission of Hepatitis C at Iranian Thalassemia Centers Shown by Genetic Characterization of Viral Strains
- 2013
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Ingår i: Hepatitis Monthly. - : Briefland. - 1735-143X .- 1735-3408. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Hepatitis C is prevalent among thalassemia patients in Iran. It is mainly transfusion mediated, in particular among patients treated before 1996 when blood screening was introduced. Objectives: The current study aimed to investigate why patients still seroconvert to anti-HCV in Iranian thalassemia centers. Patients and Methods: During 2006-2007 sera were sampled from 217 anti-HCV positive thalassemia patients at nine thalassemia centers in Tehran and Amol city, where 34 (16%) patients had been infected after 1996. The HCV subtype could be determined by sequencing and .NCR-core region in 130 strains׳5 phylogenetic analysis of partial NS5B and/or Results: 1a (53%) was predominant followed by 3a (30%), 1b (15%), and one strain each of 2k, 3k and 4a. Phylogenetic analysis revealed 19 clades with up to ve strains diverging with less than six nucleotides from each other within subtypes 1a and 3a. Strains in seven cla des were from nine patients infected between 1999 and 2005 and similar to strains from eight patients infected before 1996, indicating ongoin g transmission at the centers. Further epidemiological investigation revealed that 28 patients infected with strains within the same clade had frequently been transfused at the same shift sitting on the same bed. An additional eight patients with related strains had frequently bee n transfused simultaneously in the same room. Conclusions: The results suggest nosocomial transmission at these thalassemia centers both before and after the introduction of blood screening. Further training of sta and strict adherence to preventive measures are thus essential to reduce the incidence of new HCV infections.
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