SLIDE 1 Massachusetts 2015 Vibrio parahaemolyticus Presentation
Johanna Vostok, MPH
Massachusetts Department of Public Health
Scott Troppy, MPH, PMP
Massachusetts Department of Public Health
SLIDE 2
- Vibrio parahaemolyticus (Vp) and oysters
- National and statewide trends
- Summary of 2013 Vibrio season
- Review changes made to Vibrio events in MAVEN,
implemented May 2014
- Summary of 2014 Vibrio season
- What to expect this year
Overview
SLIDE 3
VIBRIO PARAHAEMOLYTICUS & OYSTERS
SLIDE 4 Vibrio parahaemolyticus, or Vp, is a bacterium that naturally lives off the coast of the United States and Canada and causes gastrointestinal illness in humans when consumed
- Is part of the same family of bacteria that cause cholera
What is is Vp?
SLIDE 5
- Vp naturally lives in brackish water along the coast of
Massachusetts
- Brackish water is water that has more salinity than fresh water, but not
as much as seawater
- May result from seawater mixing with freshwater, as in estuaries
- It is not an indication of pollution
- Thrives in low‐salt, high temperature environments
- Present in higher concentrations during the summer
Where does Vp come from?
SLIDE 6 Clinical features Watery diarrhea, often with abdominal cramping, nausea, vomiting, and fever. Less commonly, wound or soft tissue infections. Occasionally blood stream infections. Incubation period Less than 24 hours Duration Most persons recover after 3 days and suffer no long‐term consequences. Risk groups Everyone is at risk of infection. Individuals with underlying medical conditions, such as alcoholism and liver disease, may be at increased risk of infection and serious complications.
What type of illness does Vp cause?
SLIDE 7 Diagnosis
- Vibrio organisms can be isolated from stool, wound or
blood cultures
Treatment
- In most cases, no treatment necessary
- No evidence indicating antibiotic treatment decreases the
severity or length of illness
- Re‐hydration recommended from fluids lost due to
diarrhea
How is Vp diagnosed and treated?
SLIDE 8
- People become infected by eating raw or undercooked
shellfish, especially oysters
- Less commonly, Vp can cause an infection in the skin when an open
wound is exposed to warm seawater
- Documented in shellfish on Cape Cod as early as 1972*
*Earle and Crisley Appl. Environ. Microbiol., 1975
How does illness with Vp occur?
SLIDE 9 Oysters are filter feeders
- Feed on particles (algae) in surrounding seawater by filtering water
through gills
- Each oyster filters up to 5 liters of water per hour
- Oysters can accumulate Vp as they filter water – may result in
concentrations 100 times greater than those found in surrounding seawater
Potential for time‐temperature abuse after harvest
- Promote growth of bacteria
Consumed raw
- No opportunity for Vp to be killed
Why oysters?
SLIDE 10
NATIONAL & STATEWIDE TRENDS
SLIDE 11 Relative rates of culture‐confirmed infections compared with 2006–2008 rates, by year — FoodNet, United States, 2006–2013
MMWR April 18, 2014
SLIDE 12
SLIDE 13 Confirmed Vibrio cases in Massachusetts by species,
May 1 – October 31
8 20 22 20 39 63 32 10 20 30 40 50 60 70 80 10 20 30 40 50 60 70 80 90 100 2008 2009 2010 2011 2012 2013 2014
Percent VP Number of cases Year
Vibrio parahaemolyticus Vibrio fluvialis Vibrio alginolyticus Other Vibrio species Percent Vibrio parahaemolyticus (VP) Data as of April 21, 2015
SLIDE 14
2013 VIBRIO SEASON
SLIDE 15 2 4 6 8 10 12 14
Number of cases Week
Reported to MDPH Consumption of oysters Consumption of other seafood
Vibrio parahaemolyticus cases in Massachusetts, 2013:
week reported to MDPH vs. week of seafood consumption
5 VP cases with oyster exposure and no consumption date; 18 with no or unknown seafood consumption.
Closure Recall
SLIDE 16 2013 Challenges
- Burdensome to identify new cases in MAVEN
- Two surveillance systems used for case investigation: MAVEN &
COVIS
- Cumbersome to share information between programs
- Difficult to aggregate data, delaying public health action
SLIDE 17
CHANGES MADE TO VIBRIO EVENTS IN MAVEN
SLIDE 18
Cholera and Other Vibrio Illness Surveillance (COVIS)
SLIDE 19
Vibrio treated as an immediate disease from May 1st – October 31st
SLIDE 20 Notes from the Epi‐of‐the‐day (EOD) regarding next steps for investigation
Vp or Vibrio species in stool
Not Vp or Vibrio species in non‐ stool specimen
Old case
SLIDE 21
Vibrio Events in MAVEN
SLIDE 22
Clinical Question Package
SLIDE 23
Clinical Question Package
SLIDE 24
Risk/Exposure/Control & Prevention QPKG
SLIDE 25
Risk/Exposure/Control & Prevention QPKG
SLIDE 26
New Traceback Question Package for the MDPH Food Protection Program
SLIDE 27
2014 VIBRIO SEASON
SLIDE 28 Vibrio parahaemolyticus cases in Massachusetts, 2014:
week reported to MDPH vs. week of seafood consumption
2 4 6 8 10 12 14
Number of cases Week
Reported to MDPH Consumption of oysters Consumption of other seafood
Closure
3 VP cases with oyster exposure and no consumption date; 8 with no or unknown seafood consumption.
SLIDE 29 n Median Min Max Consumption
↓
19 1 4 Symptom onset
↓
26 4.5 9 Lab specimen collected
↓
28 5.5 19 Vibrio parahaemolyticus identified
↓
28 1 18 Report to MDPH
↓
28 4 29 Completion of CRF
Timeliness of Investigation
SLIDE 30
WHAT TO EXPECT THIS YEAR
SLIDE 31
- No additional changes have been made to MAVEN
- Same protocol as last year:
- Vibrio events will be treated as immediate events from May 1st –
October 31st
- MDPH epidemiologists will work with LBOHs to obtain case interview
within 24 hours of report of a case
The 2015 Vp Season
SLIDE 32
- WE NEED DETAILS!
- Case having difficulty recalling date, time, or location of
purchase:
- Did case pay using credit or debit card? Ask to look up bill/statement.
- Did case save paper receipt?
- Google‐‐ for restaurant name, items served on menu.
- Restaurant consumption of oysters:
- Were oysters consumed during happy hour, as an appetizer, or as a
meal?
- Was a specific type of oyster ordered?
- Are oyster types listed on restaurant/retail receipt?
Tips for Case Interview
SLIDE 33
- Vibrio parahaemolyticus Fact Sheet
http://www.mass.gov/eohhs/docs/dph/cdc/factsheets/vibrio.pdf
Additional Resources
SLIDE 34
- Vibriosis Chapter in Guide to Surveillance
http://www.mass.gov/eohhs/docs/dph/disease‐reporting/guide/vibriosis‐june‐2014.pdf
Additional Resources
SLIDE 35
Thank you
MAVEN Questions: isishelp@state.ma.us 617‐983‐6801 Case Follow‐up Questions: 617‐983‐6800
