Epidemiology, Diagnosis, Control and Prevention of Norwalk-Like- Virus Outbreaks on Cruise Ships

Transcription

1 Epidemiology, Diagnosis, Control and Prevention of Norwalk-Like- Virus Outbreaks on Cruise Ships BC Food Protection Association May 6, 2003 Susan Clay, A/ PH Manager Harsh Thakore, A/ Regional Manager Workplace and Public 1

2 Outline Epidemiology of NLV (Susan Clay) Characteristic Modes of transmission Clinical presentation Outbreak settings Treatment Prevention and Control (Harsh Thakore) Workplace and Public 2

3 Is NLV a Significant PH Problem? NLV stats for 2002: US CDC: Estimates 23 million cases Canadian PH: Estimates 1.2 million cases Northern Europe*: 12 million cases *England, Sweden, Finland and Russia Workplace and Public 3

4 Outbreaks on Cruise Ships, 2002 Princess Cruise Lines: over 450 ill pax and crew Holland America: over 600 ill pax and crew Walt Disney Cruises: over 500 ill pax and crew Norwegian Cruises: Over 300 ill pax and crew Coronia: Multiple outbreaks Others: Wilderness, Sundream, Olympic etc. Workplace and Public 4

5 Public Issues Affecting International Passenger Vessels Norwalk Like Virus (Norovirus) 2002 Rpt No. Illness Pax Sick Crew Sick Total 25 NLV ecoli Salmonella Shigella 169 nil unknown GI related problems reported (April) Workplace and Public 5

6 Epidemiology Leading cause (65%) of nonbacterial G.I. Outbreaks in and U.S.A. Affects all age groups Persons with increased susceptibility Elderly persons (68% of all cases reported) Very young children Immunocompromised Source: Infected Humans Workplace and Public 6

7 Modes of Transmission Primarily, Fecal-Oral Ingestion of contaminated food or water Ingestion of aerosolized vomitus droplets Secondary Person to Person transmission Hand-to-hand contact with vomitus/fecally contaminated skin or fomites (any contaminated object such as a door knob) Workplace and Public 7

8 Mode of Transmission of AII Outbreaks Jan Nov 2000 Foodborne 39% Waterborne 3% Person-to- Person 12% Unknown 18% Source: MMWR, June 2001 No data 28% Workplace and Public 8

9 Characteristics: What makes NLV highly communicable? Low infectious dose <10 viral particles can cause illness Multiple modes of transmission Environmental stability survives freezing and heating to 60 C Resistant to acidic conditions, vinegar, alcohol and high sugar concentrations (enables survival on produce and prepared foods) No lasting immunity Workplace and Public Source: MMWR, June

10 Clinical Presentation 30% of infections may be asymptomatic Symptoms Abrupt onset of vomiting (80%) Watery, non-bloody diarrhea (87%) Nausea (78%) Abdominal cramps Fever Headache Workplace and Public 10

11 Clinical Presentation (Cont d) Incubation period: hours Illness duration: hours Rarely severe in effect, but highly communicable to others Dehydration most common complication in young and elderly Workplace and Public 11

12 Treatment No specific therapy for the illness Replacement of fluids and electrolytes for symptomatic therapy Workplace and Public 12

13 Outbreak Settings Restaurants Nursing homes/hospitals Schools Day care centres Other (cruise ships, trains etc.) Workplace and Public 13

14 Location of Confirmed NLV OB s LTCF 65% Schools 3% Restaurants 4% Camps 5% Cruiseships 7% Other 7% Hospitals 9% Workplace and Public 14

15 Prevention and Control Measures on Cruise Ships Harsh Thakore Workplace and Public 15

16 Outline Background to HC Cruise Ship Inspection Program Reporting of Communicable Diseases to HC Prevention and Control Workplace and Public 16

17 Program Specific Objectives to protect and safeguard the health of the traveling public Program Activities support s signature to the International Regulations by the World Organization (WHO) Workplace and Public 17

18 Cruise Ship Inspection Authority Program Department of National and Welfare Act; Section 4(2) of the Act International Regulations Quarantine Act Potable Water Act and Regulations Workplace and Public 18

19 Cruise Ship Inspection Program PURPOSE AND GOALS To achieve and maintain a level of sanitation that will lower the risk of Gastrointestinal (GI) Disease outbreaks and assist the industry in its effort to provide a healthful environment for their passengers and crews. Workplace and Public 19

20 Short History of the Program Spring 1970, MV Oronsay arrives in Vancouver harbour with a full blown typhoid outbreak Ship is detained in Vancouver for over a month Ship had traveled from England to East Coast of USA and was not allowed to dock in USA by public authorities was pressured into allowing the vessel to dock flying the yellow quarantine flag and investigation was begun by National and Welfare Conclusion: Due to a cross-connection of their potable water and sewage pipes, resulting in the contamination of the entire ship s potable water system Workplace and Public 20

21 Short History of the Program This incidence highlighted a need for a better inspection and surveillance strategy for the cruise ship industry Beginning in 1970 Mr. John Yashack of US CDC began a small program monitoring cruise lines operating or visiting USA for food and water sanitation Workplace and Public At the same time in Vancouver, B.C. a small scale inspection program was initiated to inspect the ships visiting the Port of Vancouver By 1976 there were a total of about seven ships visiting Vancouver on a regular Alaska itinerary In 1977 a formal inspection process was developed in Vancouver using our regular inspection forms, and assigning a point score 21

22 Short History of the Program 1980 s saw a tremendous increase in cruise ship traveling public, and resulted in a significant growth of the industry for the Port of Vancouver. During the 1980 s regular cruise ship inspections were carried out twice per ship of all vessels visiting the Port of Vancouver There still was a lack of consistency of inspection as well as no national coordination between the East and West. By mid eighties the US vessel sanitation program was well developed with their own manual in the process of being implemented 1989 a voluntary compliance program between the cruise ship industry and USPH came into effect, precipitated by three major outbreaks of food borne illness Workplace and Public 22

23 Short History of the Program In the USA this program was a cost recovery program completely funded by the cruise ship industry 1990, Vancouver Inspectors were struggling to adopt an inspection program similar in scope to the US. However, without national agreements and lack of funding it was a very disjointed program 1995 saw the separation of Indian from Public Service, and the creation of OHSA in This same year under the leadership of Mr. Sandy Cocksedge, the first meeting to negotiate a harmonization between USA and took place in Miami, Florida. Several joint meeting between USA and followed. USA inspectors were and are still today reluctant to negotiate a fully reciprocal inspection program. This is the wish of the industry. Workplace and Public 23

24 Short History of the Program In Fall1997 OHSA negotiated a voluntary compliance program with the cruise industry on a full cost recovery basis. Finally we had an agreement which was national in scope. agreed to use the USPH guidelines for inspection and carry out one inspection per ship each year. This inspection program became a reality in spring of 1998 This was also the year when a large outbreak of Norwalk type virus illness occurred on the West Coast, as well as a respiratory illness outbreak happened on the East Coast. Our resources were stretched to their limits, however, we proved to the industry, as well to the USPH that we could cope with such emergencies. Workplace and Public 24

25 Cruise ship Inspection Form 5 sections - 41 items Disease Reporting (5) Potable Water (21) Swimming Pools & Spas (4) Food Safety (53) Personnel (13) Food (17) Equipment (17) Toilet and hand washing Facilities (4) Toxic Substances (5) Facilities (8) Environmental (6) Integrated Pest Management Housekeeping and Child Activity Centers Workplace and Public 25

26 Potable and Recreational water Workplace and Public 26

27 Food Safety Workplace and Public 27

28 Workplace and Public 28

29 Workplace and Public 29

30 Prevention/Control Measures 1. Surveillance Mandatory GI logs Mandatory Inventory of antidiartheal medications sold Mandatory reporting of ill crew to medical officer Workplace and Public 30

31 Prevention/Control Measures 2. Reporting GI illness report is submitted to HC 24 hours before vessel s arrival in Canadian waters Special Reporting: immediate reporting of vessels destinate for Canadian waters when GI illness rates reach 2% Additional reporting: Quarantine Act Workplace and Public 31

32 Electronic Reporting Workplace and Public 32

33 Prevention/Control Measures Educate staff to identify and immediately report ill passengers or crew Notify Mgt Management to notify : **Immediate identification and notification of ill passengers or crew will greatly improve the chances of controlling the outbreak at the early stages Workplace and Public 33

34 Prevention/Control Measures Isolation of infected individuals Exclude food handlers with current vomiting, diarrhea, or history of symptoms within past 72 hrs. Isolation of infected passengers Recommendation only Workplace and Public 34

35 Prevention/Control Measures Aggressive disinfection 1000 ppm Chlorine for all hard contact surfaces Accelerated hydrogen peroxide to disinfect soft furnishings NB: Non-synergistic Workplace and Public 35

36 Prevention/Control Measures Establish procedures for soiled linens and clothes Wear gloves and handle with minimal agitation to prevent aerosolization of viral particles Bag Soiled Linens Separately in Properly Labeled bags/bins Launder with detergent on Hot Water Cycle Workplace and Public 36

37 Prevention/Control Measures Educate staff on importance of good personal hygiene Proper hand washing videos Educate passengers re: good personal hygiene Daily news releases from Captain Workplace and Public 37

38 Prevention/Control Measures Provision of safe food and water Ensure food safety Storage (Cold Vs Hot) Preparation (adequate temperature) Holding (protected) Serving Adequate food temp. Good personal hygiene Provision of safe water Workplace and Public 38

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