Dissemination of gastroenteric viruses in the production of lettuce in developing countries: a public health concern.

Investigation of major viruses responsible for acute viral gastroenteritis, such as norovirus (NoV), rotavirus species A (RVA) and human adenovirus (HAdV), was conducted in the mountainous region of the state of Rio de Janeiro in a lettuce-producing area. Irrigation water and lettuce samples were collected at different production stages. Viruses were concentrated using an adsorption-elution method and detected by quantitative polymerase chain reaction (qPCR). We detected HAdV in all collection points, although no virus infectivity was shown. The RVA was the most prevalent virus from both water (16.7% [10/60]) and lettuce samples (11.1% [4/36]), with loads ranging from 2.97 × 102 to 6.88 × 103 genomic copies per litre (gc L-1) and 6.24 × 102 to 1.30 × 104 gc per 25 g, respectively. NoV was detected in 8.33% [8/96] in water and lettuce samples, with concentrations ranging from 7.29 × 101 to 1.92 × 103 gc L-1 and from 4.29 × 101 to 2.98 × 103 gc 25 g-1, respectively. Escherichia coli values also demonstrated poor quality of the irrigation and washing water. The presence of at least two different virus strains in all sites reveals the need to improve basic sanitation measures in order to increase food safety.

Group A rotavirus detection on environmental surfaces in a hospital intensive care unit.

BACKGROUND: Environmental surfaces can play a role in the spread of pathogens, such as enteric viruses, within a hospital. This study assessed the level of contamination of group A rotavirus (RV-A) on environmental surfaces samples from an adult intensive care unit in a hospital in Rio de Janeiro, Brazil. METHODS: A total of 504 environmental surface samples were obtained from multiple sites in the intensive care unit, including flushing buttons, telephones, and alcohol gel supports. Nested and quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) were used to detect and quantify RV-A levels through partial amplification of VP6 and NSP3 genes, respectively, and the viability of the viruses detected was assessed by MA-104 cell integrated cell culture/RT-PCR. RESULTS: RV-A was detected by nested RT-PCR in 14% of the samples (73 of 504), with viral loads ranging from 3.4 genomic copies/mL to 2.9 × 10(3) genomic copies/mL. The nucleotide sequence of the amplicons obtained from nested RT-PCR confirmed that the positive samples were RV-A. Moreover, 3 of 10 strains investigated demonstrated viability by integrated cell culture/RT-PCR. CONCLUSION: The detection of RV-A on environmental surface samples indicates a need for improvements to hospital cleaning procedures to reduce viral contamination, and suggests, as reported previously, that RV-A can be used as a biomarker to assess contamination in hospitals.