Norovirus shedding among food and healthcare workers exposed to the virus in outbreak settings

作者:Sabria Aurora; Pinto Rosa M; Bosch Albert; Bartolome Rosa; Cornejo Thais; Torner Nuria; Martinez Ana; de Simon Mercedes; Dominguez Angela; Guix Susana
来源:Journal of Clinical Virology, 2016, 82: 119-125.
DOI:10.1016/j.jcv.2016.07.012

摘要

Background: Noroviruses (NoV) are highly contagious and the leading cause of nonbacterial outbreaks of gastroenteritis worldwide. Individuals who are infected asymptomatically may act as reservoirs and facilitate the transmission of NoV, but the likelihood of workers of becoming infected in outbreak settings has not been systematically studied. Objectives: We evaluated the occurrence of norovirus infections among workers exposed to the virus in different outbreak settings. Study design: We screened feces from food handlers and healthcare workers related with gastroenteritis outbreaks, and shedding concentrations over time were calculated from serial samples of infected individuals. Sequence analyses of the capsid P2 domain and region C were used to evaluate linkage between asymptomatic employees and outbreak cases. Results: Of all employees, 59.1% were positive for NoV, and more than 70% of them were asymptomatic. Asymptomatic infections were significantly more frequent in foodborne compared to person-to-person transmitted outbreaks; and in restaurants and hotels, compared to nursing homes and healthcare institutions. Mean viral loads were similar between symptomatic and asymptomatic individuals, starting at 7.51 +/- 1.80 and 6.49 +/- 1.93 login genome copies/g, respectively, and decreasing to 5.28 +/- 0.76 and 4.52 +/- 1.45 log(10) genome copies/g after 19 days. Conclusions: The likelihood of becoming infected when a NoV outbreak occurs at the work place is high and similar between food handlers and healthcare workers, but asymptomatic infections are more frequently identified among food handlers. Since shed amounts of viruses in the absence of symptoms are also high, reinforcement of hygiene practices among workers is especially relevant to reduce the risk of virus secondary transmissions.

  • 出版日期2016-9