Water- and foodborne viruses : current developments : water and food are still major sources of enteric viruses

Despite the major advances made in preventive health care and food technology, water and foodborne transmission of human enteric viruses is a well-recognised widespread public health problem. Factors such as changing lifestyles and demographics, faster and more frequent travel, decreasing water supplies and the globalisation of the food industry have contributed to the increase in water- and foodborne infections. Water and food contaminated with viruses may conform to acceptable bacterial standards and look, taste and smell normal.http://www.cmej.org.za/index.php/cme

Novel norovirus recombinants detected in South Africa

BACKGROUND: Noroviruses (NoV) are the leading cause of viral gastroenteritis worldwide. Recombination frequently occurs within and between NoV genotypes and recombinants have been implicated in sporadic cases, outbreaks and pandemics of NoV. There is a lack of data on NoV recombinants in Africa and therefore their presence and diversity was investigated in South Africa (SA). RESULTS: Between 2010 and 2013, eleven types of NoV recombinants were identified in SA. Amplification of the polymerase/capsid region spanning the ORF1/2 junction and phylogenetic analysis confirmed each of the recombinant types. SimPlot and maximum x(2) analysis indicated that all recombinants had a breakpoint in the region of the ORF1/2 junction (P < 0.05). The majority (9/11) were intergenotype recombinants, but two intragenotype GII.4 recombinants were characterised. Three combinations represent novel recombinants namely GII.P not assigned (NA)/GII.3, GII.P4 New Orleans 2009/GII.4 NA and GII.P16/GII.17. Several widely reported recombinants were identified and included GII.P21/GII.2, GII.P21/GII.3, GII.Pe/GII.4 Sydney 2012, and GII.Pg/GII.12. Other recombinants that were identified were GII.Pg/GII.1, GII.Pe/GII.4 Osaka 2007, GII.P4 New Orleans 2009/GII.4 Sydney 2012, GII.P7/GII.6. To date these recombinant types all have a reportedly restricted geographic distribution. This is the first report of the GII.P4 New Orleans 2009/GII.4 Sydney 2012 recombinant in Africa. CONCLUSIONS: Over the past four years, remarkably diverse NoV recombinants have been circulating in SA. Pandemic strains such as the GII.Pe/GII.4 Sydney 2012 recombinant co-circulated with novel and emerging recombinant strains. Combined polymerase- and capsid-based NoV genotyping is essential to determine the true diversity and global prevalence of these viruses

Quantification and molecular characterisation of human sapoviruses in water sources impacted by highly polluted discharged wastewater in South Africa

Sapoviruses (SaVs) were detected and quantified in 8/10 water samples collected from wastewater treatment works (WWTW) and water sources impacted by these WWTWs in Limpopo Province, South Africa. The median SaV concentration was 2.45 x 106 copies/L and SaV genotypes I.2 and IV were characterised. This study provides new data on the high concentrations of clinically relevant SaVs in rivers and dams impacted by poor-performing WWTWs.This study was funded, in part, by the Poliomyelitis Research Foundation, and in part by an on-going solicited Water Research Commission research project co-funded by Department of Agriculture, Forestry and Fisheries, SA. “An investigation into the link between water quality and microbiological safety of fruit and vegetables from the farming to the processing stages of production and marketing” (Project No K5/1875//4, Water Research Commission Abridged Knowledge review 2009/10, Pretoria).http://jwh.iwaponline.comhb2016Medical Virolog

Molecular characterisation of hepatitis : a virus strains from water sources in South Africa

Hepatitis A virus (HAV) strains found in selected South African (SA) surface waters were characterised to establish what HAV types are circulating in the environment, thus reflecting circulation in the surrounding communities. Surface water samples used for irrigation or domestic purposes, and water samples from the outflow of wastewater plants were collected from six provinces. Viruses were recovered from the samples using a glass wool adsorption-elution method and then further concentrated using polyethylene glycol/sodium chloride precipitation. After automated nucleic acid extraction, samples were analysed for HAV by real-time reverse-transcriptase polymerase chain reaction. HAV strains were genotyped by nucleotide sequence analysis of the capsid gene VP1 and the VP1/P2B junction. HAVs were detected in 76% (16/21) of the surface water samples and in 37% (19/51) of the samples from the wastewater plants. Strains were characterised from 32 of the 35 samples and classified within genotype IB. The presence of genotype IB in the water sources confirms human faecal contamination. Hence, these faecally-contaminated water sources may be a potential transmission route of HAV infection and a potential source of contamination of irrigated fresh produce in SA.Rachida Saïd was supported by a Poliomyelitis Research Foundation post-graduate bursary. This study was funded, in part, by the National Research Foundation (NRF), and in part by an on-going solicited research project (K5/ 1875//4) funded by the WRC and co-funded by the Department of Agriculture, Forestry and Fisheries, South Africa.http://www.iwaponline.com/wst/toc.htmhb201

First detection of human sapoviruses in river water in South Africa

Over a 2-year period, from January 2009 to December 2010, water samples were collected from three rivers (Klip, Rietspruit and Suikerbosrand) in the Vaal River System, South Africa. Enteric viruses were recovered by a glass wool adsorption–elution method and concentrated using polyethylene glycol/sodium chloride precipitation. Sapoviruses (SaVs) were detected using published sapovirus (SaV)-specific primers and Taqman probes in a two-step real-time reverse transcription-polymerase chain reaction assay. Based on sequence analysis of the 50-end of the capsid gene, SaVs were genotyped. In 2009, SaVs were detected in 39% (15/38) of samples from the Klip river, 83% (5/6) from the Rietspruit and 14% (1/7) of samples from the Suikerbosrand river. In 2010, SaVs were detected in 54% (14/26) of Klip river samples, 92% (11/12) from the Rietspruit and 20% (2/10) of samples from the Suikerbosrand river. SaV strains identified in the water samples were characterised into several GI and GII genotypes. The presence of SaVs in these rivers indicates human faecal contamination which may pose a potential health risk to persons exposed to these water sources during domestic or recreational activities.Poliomyelitis Research Foundation and National Research Foundation (NRF), Iliso Consulting and the Medical Research Council of South Africahttp://www.iwaponline.comhb201

Circulation of classic and recombinant human astroviruses detected in South Africa : 2009 to 2014

BACKGROUND : Astroviruses (AstVs) are associated with diarrhoeal and extra-intestinal infections in human, animal and avian species. A prevalence of 7% was reported in selected regions in SA while AstVs detected from clinical stool specimens were almost identical phylogenetically to strains identified in environmental and water samples. This study investigated the molecular diversity of astroviruses circulating between 2009 and 2014 in South Africa (SA). METHODS : Astroviruses detected in stool specimens collected from hospitalised children were investigated retrospectively. Astroviruses were characterised using type-specific RT-PCR, partial nucleotide sequence analyses in ORF1 and ORF2 and whole genome sequencing. Different genotypes were compared with clinical features to investigate genotype-related associations. The Vesikari severity scale (VSS) was evaluated for scoring astrovirus diarrhoeal infections. RESULTS : Of 405 astroviruses detected, 49.9 % (202/405) were characterised into 32 genotypes comprising 66.3 % (134/202) putative-recombinants and 33.7 % (68/202) classic strains. No trends by year of collection, age or site were observed. Whole genome analysis in eight strains revealed that genotypes assigned by partial nucleotide sequence analyses to five astroviruses were incorrect. Bivariate analyses showed there were no significant associations between genotypes and clinical symptoms or severity of infection. A comparison of Vesikari parameters with astrovirus-positive proxy values demonstrated that Vesikari scores for duration of diarrhoea and admission temperatures would result in a milder infection rating in astrovirus-positive cases. CONCLUSIONS : Diverse genotypes co-circulated with putative-recombinants predominating. Astrovirus classification was complicated by the lack of a consistent characterisation system and reliable reference database. The VSS should be used cautiously to rate astrovirus diarrhoea. While surveillance in communities and out-patient clinics must be continued, screening for human astroviruses in alternate hosts is needed to determine the reservoir species.The Rotavirus Sentinel Surveillance program was funded by GlaxoSmithKline (E-Track 200238). Research was supported by a National Health Laboratory Service Research Grant and the Poliomyelitis Research Foundation.http://www.elsevier.com/locate/jcv2021-12-31hj2021Medical Virolog

Human calicivirus diversity in wastewater in South Africa

AIM : To investigate the diversity of human caliciviruses (HuCVs) in wastewater from small- to medium-sized communities in five provinces of South Africa (SA). METHODS AND RESULTS : Wastewater samples (51) were screened for norovirus (NoV) GI, GII, GIV and sapovirus (SaV) using real-time reverse transcription (RT)-PCR. Partial capsid nucleotide sequences were analysed for genotyping. At least one HuCV was detected in 42 samples (82%) with NoV GI being detected in 15 (29%), NoV GII in 32 (63%) and SaV in 37 (73%) samples. NoV GIV was not detected. Five NoV GI genotypes (GI.1, GI.3, GI.4, GI.8 and GI.unassigned), eight NoV GII genotypes (GII.2, GII.3, GII.4, GII.6, GII.7, GII.12, GII.13 and GII.17) and six SaV genotypes (GI.2, GI.3, GI.6, GI.7, GII.1 and GII.2) were characterized. CONCLUSIONS : Many NoV and SaV genotypes were detected in wastewater, demonstrating a high genetic diversity of HuCVs in the surrounding communities. Caliciviruses were characterized from several provinces in SA, indicating widespread occurrence in the country. SIGNIFICANCE AND THE IMPACT OF THE STUDY : This study provides valuable new data on CVs circulating in SA, including the first data on SaV strains from wastewater in Africa. Environmental surveillance is especially important in countries like SA where outbreak reporting systems or routine HuCV surveillance is lackinghttp://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1365-2672hb2013ay201

Norovirus GII.17 predominates in selected surface water sources in Kenya

In this study, the prevalence and genotypes of noroviruses (NoVs) in selected water sources from rural, urban and refugee settings in Kenya were investigated. Ten litres each of river, household and borehole water was collected in rural (Mboone River), urban (Nairobi and Mutoine River) and refugee (Dadaab refugee camp) settings. NoVs were recovered from the water samples by a glass wool adsorption–elution technique and/or PEG/NaCl precipitation. Nucleic acid was extracted using the automated MagNA Pure platform. NoVs were detected with singleplex real-time reverse transcription-polymerase chain reaction assays and characterised by nucleotide sequence analysis. NoVs were detected in 63 % (25/40) of the selected water samples comprising GII (42.5 %), GI (2.5 %) and mixed GI/GII (17.5 %) positive samples. The prevalence of NoVs in the Mutoine River (urban area) was higher than in the Mboone River (rural area) (P = 0.0013). Noroviruses GI.1, GI.3, GI.9, GII.4, GII.6, GII.12, GII.16 and GII.17 were identified, with GII.17 accounting for 76 % (16/21) of the typed strains. The NoV GII.17 predominance differs to other studies in Africa and further surveillance of NoVs in clinical and environmental settings is required to clarify/elucidate this observation. As information regarding NoVs in Kenyan water sources is limited this report provides valuable new data on NoV genotypes circulating in environmental water sources and the surrounding communities in Kenya.The National Research Foundation, South Africa and the National Council for Science and Technology, Kenya: South Africa/Kenya Research Programme.http://link.springer.com/journal/12560hb2017Medical Virolog

Molecular detection and characterisation of mumps virus in cerebrospinal fluid in a Gauteng laboratory

The study aimed to determine the presence of mumps virus (MuV) in cerebrospinal fluid (CSF) specimens and to genetically characterise detected MuV strains. A real-time reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the MuV F gene, and characterisation was performed by sequencing of the SH gene. Mumps virus was detected in 1.2% (3/260) of specimens. Phylogenetic analysis of one MuV strain revealed that it clustered with the Jeryl-Lynn and RIT4385 vaccine strains. As far as the authors could ascertain this is the first study to provide viral proof that these vaccine-like strains may be associated with aseptic meningitis.The information contained in this article was presented by Marieke Brauer at the UNIPATH 2014 conference, held on 19-21 September 2014 at the CSIR Convention Centre in Pretoria (no abstract number available).http://www.sajei.co.za/index.php/SAJEIam2016Medical Virolog