Vibrio Parahaemolyticus Control Plan

Purpose and Scope

This Vibrio parahaemolyticus (Vp) Control Plan is implemented in accordance with the National Shellfish Sanitation Plan Model Ordinance (NSSP MO) Section II Chapter II @.07 (adopted by reference at 18 AAC 34 under the authority of AS 17.20.005).

The goal of this plan is to reduce the probability of occurrence of Vp illness during periods that have been historically associated with illness and is part of a comprehensive program that includes all time and temperature requirements contained in the NSSP MO. The plan is based on the Alaska Department of Environmental Conservation (ADEC) Vp Risk Evaluation.

The plan outlines actions that the ADEC and all active oyster growing, harvesting, and dealer operations take from June 15 through September 15, the time period when, historically, water temperatures of classified growing areas in Alaska have exceeded 60°F, a water temperature that has been associated with confirmed Vp illnesses in Alaska in the past (PDF) and is representative of harvesting conditions that prompt the need for a control plan. The plan also describes response activities relating to the risk management of shellfish-related illnesses associated with Vp, in accordance with NSSP MO Section II Chapter II @.02.

For the remainder of the year when this plan is not in effect, September 16 through June 14, control of temperature to harvest must be accomplished as specified in the NSSP MO Section II Chapter VIII.

Additional requirements and resources may be found at:

Control Measures

This plan calls for three control measures:

Water Temperature Monitoring
Control of Time from Harvest to Temperature Control
Control of Time and Internal Temperature After Temperature Control

Trigger to Implement Control Measures

The sole trigger for plan implementation is the time period June 15 through September 15.

Water Temperature & Salinity Monitoring
- Weekly monitoring
- If a weekly temperature ≥ 60° F, then notify ADEC, monitor daily, and either stop harvest & lower gear or shorten time from harvest to temperature control
Time from Harvest to Temperature Control
- Within 5 hours after first shellstock harvested, if temperature is < 60° F; or
- WIthin 3 hours, if temperature is ≥ 60° F; or
- WIthin 1 hour, if temperature is ≥ 68° F
Time & Internal Temperature After Refrigeration (Original Dealer)
- Internal temperature ≤ 50° F
- Within 10 hours after temperature control

Water Temperature & Salinity Monitoring

1. The grower must
  - At least once each 7 days, measure ¹ the water temperature and salinity at the top of the suspended aquaculture gear at or about 5 p.m., or when water temperatures are typically the warmest ²; and
  - document the date, time, specific location (depths), temperature and salinity for each measurement on a monitoring record that is kept at the growing site and, during the season, made the data available to ADEC on request; and
  - Submit to ADEC, by October 1, a copy of the weekly temperature and salinity monitoring records.
2. If the weekly water temperature at the top of suspended gear is ≥ 60° F (15.6° C), the grower must
  - immediately notify the department by phone, fax, or email;
  - daily, measure the water temperature at the top of the suspended aquaculture gear at or about 5 p.m., or when water temperatures are typically the warmest; and
  - document the date, time, specific location (depth), and temperature value for each measurement on a monitoring record that is kept at the growing site and, during the season, make the data available to ADEC on request; and
  - Submit to ADEC, by October 1, a copy of daily temperature and salinity monitoring records.
3. In addition to implementing daily monitoring, the grower must either
  - stop harvest and lower the aquaculture gear below the thermocline for at least 10 days before harvesting; or
  - follow the time temperature control parameters below:
    - If the water or ambient air temperature is ≥ 68° F1 hour after the first shellstock harvested is no longer submerged.
    - If the water or ambient air temperature is ≥ 60° F and not more than ≥ 67˚ F at the time of harvest, cool the shellstock within 3 hours after the first shellstock harvested is no longer submerged.
4. A grower may raise gear or resume following Vp Time/Temperature Controls in (2), and return to weekly water temperature monitoring after 10 consecutive water temperature values (taken once each day as described above) show temperatures ≤ 59˚ F.

Control Time from Harvest to Temperature Control

1. The harvester must place shellstock under temperature control³ within 5 hours after the first shellstock harvested is no longer submerged; and
2. For each lot of shellstock harvested,
  - Record the time and air temperature when the first shellstock harvested is no longer submerged; and
  - Record the time and temperature of shellstock when placed into under temperature control.

Control Time/ Internal Temperature after Refrigeration (Original Dealer)

1. The original dealer must take actions in accordance with the firm’s HACCP plan, which must include controls, monitoring, and verification procedures to ensure that the internal temperature of oysters has reached < 50°F (10°C) within 10 hours ⁴ of being placed under refrigeration; and
2. For each lot received,
  - Record the time and air temperature at time of packing; and
  - Record the time and temperature of shellstock at time of shipping⁵

Summary of Changes:

2016: plan reformatted, rewritten, clarified requirements
2017: plan clarified and revised to allow option of shortened temperature control from harvest when gear is not lowered, provide additional guidance links, clarify record keeping requirements

Vp Illness Risk Management

After conducting an investigation to determine whether an epidemiological association exists between a Vp illness associated with consumption of shellfish harvested from a shellfish growing area and the illness was not related to post-harvesting contamination or mishandling, ADEC will calculate the risk per 100,000 servings and take action as described below:

Risk Does Not Exceed 1/100,000 within 30 daysorNo More Than 4 Cases w/in 30 Days and In Which No More Than 2 Cases from 1 Harvest Day: Determine extent of implicated area; and; Make reasonable attempts to ensure compliance with this plan; If closed, an area remains closed for a minimum of 7 days.
Risk Exceeds 1/100,000 within 30 daysor5 to 10 Cases w/in 30 Daysor2-3 Cases from 1 Harvest Day: Determine extent of implicated area; and; Immediately close implicated portion(s) of growing area; and; Transmit to FDA and receiving States, identifying dealer/shipper information.; If closed, an area remains closed for a minimum of 14 days.
More Than 10 Cases w/in 30 Daysor4 Cases from 1 Harvest Day: Determine extent of implicated area; and; Immediately close implicated portion(s) of growing area; and; Initiate product recall unless implicated product is no longer available on the market or a recall would not be effective in preventing additional illness (ADEC determines); and; Issue a consumer advisory for implicated species.; If closed, an area remains closed for a minimum of 21 days.

¹Growers must use a properly calibrated thermometer to measure water temperature. Guidance detailing how to calibrate a thermometer and examples of calibration records: Thermometer Calibration Guide, Thermometer Calibration Log
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