Norovirus in a United States virgin islands resort: outbreak investigation, response, and costs

J Travel Med. 2016 Jun 13;23(5). doi: 10.1093/jtm/taw040. Print 2016 May.

Abstract

Background: During 8-20 April 2012, an outbreak of gastrointestinal illness occurred among guests and employees of a resort hotel in St. Thomas, US Virgin Islands. We describe outbreak characteristics, and estimate indirect (non-medical) costs to travellers.

Methods: Employees who met the case definition were interviewed and provided stool samples. Samples were tested for norovirus by real-time reverse-transcription polymerase chain reaction. Guests were asked to complete a survey aimed to identify and characterize cases, and to estimate quality adjusted vacation days (QAVD) lost.

Results: Overall, 66 persons (20 employees and 46 guests) met the probable case definition. The first reported illness onset occurred in a hotel employee on 8 April, while the first reported onset in a guest occurred on 13 April. An employee suffered a public diarrhoea incident on 13 April in the central kitchen, followed by illness onset in the next day among employees that assisted with the clean-up. On 15 April, after 10 guests reported ill, the hotel implemented an outbreak response protocol instructing ill employees to take a 3-day leave, and obtain medical clearance prior to resuming work. Ill guests were advised to self-isolate, and rapid cleaning of public areas and guest rooms where suspected contamination occurred was implemented. We estimated that 65 QAVDs were lost by 43 guests (1.5 days/guest). Using an approximate cost of $450 per vacation day, we estimated indirect illness cost at $675 per guest case. Seven (64%) of 11 cases' stool specimens were positive for norovirus genotype GII.4 Den Haag.

Conclusions: A norovirus outbreak in a resort hotel resulted in substantial indirect costs and loss of vacation days to ill travellers. We recommend outbreak control measures including exclusion of ill employees, until ≥48-72 h after resolution of symptoms, self-isolation of ill guests and appropriate cleaning in hotel-associated norovirus outbreaks.

Keywords: Norovirus; US virgin islands; indirect cost; outbreak; resort.

MeSH terms

  • Caliciviridae Infections / diagnosis
  • Caliciviridae Infections / epidemiology*
  • Diarrhea / diagnosis
  • Diarrhea / epidemiology*
  • Disease Outbreaks / statistics & numerical data*
  • Female
  • Gastroenteritis / diagnosis
  • Gastroenteritis / epidemiology*
  • Humans
  • Norovirus / isolation & purification
  • Travel*
  • United States Virgin Islands