1. Paula Meza
Norovirus (NV) is a virus commonly associated with diarrhea, vomiting, fever, myalgia,
abdominal cramps and general malaise. Population most recently effected with outbreaks is cruise ships
travelers. Cruise-ship outbreaks demonstrate how easily noroviruses can be transmitted from person to
person in a closed environment, resulting in large outbreaks. NV is considered the leading cause of
adult gastroenteritis outbreaks worldwide and is thought to be second only to Rotavirus in terms of all
causes of gastroenteritis. Recent improvements in diagnostics and surveillance are likely to reveal even
more outbreaks being detected aboard ships. The probable role of international travelers as vectors is
revealed by the similarity of strains between outbreaks across the world. NV can be transmitted by
airborne transmission as well as via ingestion.
In many countries, including the US, infectious agents are categorized in risk groups based on
their relative risk. Factors that are taken into consideration include: pathogenicity of the organism,
mode of transmission, and the availability of effective preventive measures and treatment. WHO
classifies NV as a Level 2 Risk Group. This level means: moderate individual risk, low community risk. A
pathogen that can cause human or animal disease but is unlikely to be a serious hazard to laboratory
workers, the community, livestock or the environment. Laboratory exposures may cause serious
infection, but effective treatment and preventative measures are available and the risk of spread of
infection is limited.
Treatment of NV on cruise ships (and other venues, including hospitals) includes: Taking extra
precautions (airborne, droplet) with those infected or symptomatic, or quarantining those individuals to
their rooms or cabin. Prompt cleaning and disinfection of areas contaminated by vomit and feces

2. should be done immediately – additionally emphasis must be given to cleaning staff and crew regarding
hand washing after contact with affected passengers or crew and objects, before handling food or drink
and on leaving an affected room or cabin.
Sources:
ABSA.org (American Biologic Safety Association)
WHO.int (World Health Organization International)