Surveillance to Prevent the Spread of Norovirus Outbreak from Asymptomatic Food Handlers during the PyeongChang 2018 Olympics

The human noroviruses are major causes of nonbacterial gastroenteritis, and are transmitted by both food and water, as well as via a person-to-person route. Asymptomatic norovirus infection of food handlers may play a role in transmission. The outbreak of noroviruses infections has been recognized in PyeongChang Winter Olympics, starting with security staffs from February 3, 2018. The Ministry of Food and Drug Safety in Korea conducted a noroviruses surveillance from asymptomatic food handlers of food catering facilities related to the Olympics to prevent the spread of the noroviruses. A total of 707 rectal swab samples from food handlers were collected and examined for norovirus using real-time RT-PCR and conventional RT-PCR. Five of 707 detected noroviruses. Genotypes of the norovirus-positive samples were determined with sequencing analysis. Identified genotypes of norovirus in asymptomatic food handlers included GI.3, GII.4, and GII.17. The GII.17 was prevalent among the genotypes, accounting for 3 of 5 detections. Food handlers with noroviruses detected in rectal swab are excluded from cooking and all foods handled by infected food handlers were discarded. Surveillance of norovirus infection for food handlers contributed to preventing noroviruses spread.

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Enteric calicivirus and rotavirus infections in domestic pigs

Epidemiology and Infection ◽

10.1017/s0950268809990872 ◽

2009 ◽

Vol 138 (4) ◽

pp. 542-548 ◽

Cited By ~ 30

Author(s):

N. HALAIHEL ◽

R. M. MASÍA ◽

M. FERNÁNDEZ-JIMÉNEZ ◽

J. M. RIBES ◽

R. MONTAVA ◽

...

Keyword(s):

Real Time ◽

Rt Pcr ◽

Northern Spain ◽

Group V ◽

Human Noroviruses ◽

Group Iii ◽

Group I ◽

Faecal Samples ◽

Faecal Consistency ◽

Group A

SUMMARYWe report the prevalence of rotavirus and calicivirus infections, along with their respective association with diarrhoea in the porcine population of the region of northern Spain. A total of 221 samples were collected at random from different farms in the region and from the main slaughterhouse facility in the city of Zaragoza. Faecal samples were scored as diarrhoeic or normal and grouped into five groups to match general farm management and age criteria: group I (suckling 0–4 weeks), group II (weaning >4–8 weeks), group III (transition >8–16 weeks), group IV (fattening >16–24 weeks) and group V (adults >24 weeks). Group A rotavirus detection and caliciviruses were investigated by reverse transcription–polymerase chain reaction (RT–PCR). Conventional RT–PCR was performed using primers designed to detect rotavirus group A, caliciviruses and/or human noroviruses. A real-time RT–PCR was carried out using TaqMan probes for genogroups GI and GII of noroviruses. Rotaviruses and caliciviruses were detected with an overall prevalence of 16·7% and 12·2%, respectively. Rotavirus detection in faecal samples was associated with both age and faecal consistency, being more frequent in piglets aged <8 weeks with odds ratios (ORs) equal to 4·3 and 4·9, respectively. Calicivirus shedding in faecal samples was homogenously distributed in all ages, showing no significant association with age or faecal consistency (OR 0·87 and 0·99, respectively). A selection of rotavirus-positive stools were genotyped by multiplex nested PCR. G10, P[6], G12 P[8], G9 [p8] and G4 P[23] genotype combinations were found. Three isolates showed a G3 genotype, but their VP4 gene could not be amplified. It should be noted that the G9 genotype was the major G genotype circulating during that period in Spain. None of the porcine samples was positive for norovirus by real-time RT–PCR, despite the ability of this technique to detect at least 18 human norovirus genotypes. Our data indicate that human noroviruses are unlikely to be circulating in the porcine population; however, sapoviruses have been found. Contrary to rotavirus infection, Calicivirus infection is asymptomatic. Specific primers to detect porcine noroviruses are needed.

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Characterization of Ozone Disinfection of Murine Norovirus

Applied and Environmental Microbiology ◽

10.1128/aem.01955-09 ◽

2009 ◽

Vol 76 (4) ◽

pp. 1120-1124 ◽

Cited By ~ 42

Author(s):

Mi Young Lim ◽

Ju-Mi Kim ◽

Jung Eun Lee ◽

GwangPyo Ko

Keyword(s):

Public Health ◽

Reverse Transcriptase ◽

Real Time ◽

Plaque Assay ◽

Murine Norovirus ◽

Rt Pcr ◽

Human Noroviruses ◽

Pcr Assays ◽

Ozone Disinfection

ABSTRACT Despite the importance of human noroviruses (NoVs) in public health, little information concerning the effectiveness of ozone against NoVs is available. We determined the efficacy of ozone disinfection using murine norovirus (MNV) as a surrogate of human NoV. MNV in ozone demand-free buffer was exposed to a predetermined dose of ozone at two different pHs and temperatures. The virus remaining in the solution was analyzed by plaque assay, real-time TaqMan reverse transcriptase PCR (RT-PCR) (short template), and long-template conventional RT-PCR. Under all conditions, more than 99% of the MNV was inactivated by ozone at 1 mg/liter within 2 min. Both RT-PCR assays significantly underestimated the inactivation of MNV, compared with that measured by plaque assay. Our results indicate that NoV may be more resistant to ozone than has been previously reported. Nevertheless, proper ozone disinfection practices can be used to easily control its transmission in water.

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