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<p>The long term goal of the project is to reduce the overall burden of enteric illness in residents and island visitors associated with the consumption of molluscan shellfish on the island of Puerto Rico. The primary goal of this effort is to garner the information needed to make specific recommendations for development of an island-wide molluscan shellfish sanitation program. Studies are proposed to assess the extent of shellfish bed contamination in surface waters supporting the food supply of Puerto Rico and to document the presence or absence of pathogens in molluscan shellfish sold in retail markets in Puerto Rico. A training program will also be established to provide designated agency employees with the training needed to conduct routine surveillance of surface waters and molluscan shellfish for enteric pathogens.</p>
<p>Specific objectives include:</p>
<ol>
<li>Estimating the prevalence of noroviruses and other enteric pathogens in molluscan shellfish harvested in Puerto Rican waters and sold in local Puerto Rican markets;</li>
<li>Assessing vendor and consumer knowledge of the risk posed by consuming raw shellfish;</li>
<li>Using the collected environmental and survey data to develop appropriate outreach activities and materials for public education;</li>
<li>Developing and conducting a workshop to train state, and federal workers in the design, and implementation of shellfish sanitation programs;</li>
<li>Establishing a continuing education program for sustaining molluscan shellfish food safety education and training efforts.</li>
</ol>
<p>The field and laboratory studies will provide the information needed to conduct a more comprehensive risk analysis of the hazard posed to island residents and travelers that consume shellfish harvested from Puerto Rican coastal waters. The studies will demonstrate the potential utility of adapting National Shellfish Sanitation Program guidelines for the sanitary control of shellfish, and highlight the need for more active involvement of US and Puerto Rican regulatory agencies in the harvesting and marketing of seafood commodities on the island. The proposed surveys will also help guide the development of educational materials and identify appropriate distribution media for reaching island residents and tourists. We anticipate these activities should have a multiplying effect and markedly benefit overall efforts to reduce the burden of illness associated with raw shellfish consumption. The workshop and listserv will help establish a network of trained laboratory workers that we envision will eventually be the backbone of a shellfish sanitation program for the island. We will also work with IICA and other Caribbean agencies to conduct the workshop at other sites in the Caribbean.</p>
<p>NON-TECHNICAL SUMMARY: Molluscan shellfish for human consumption are harvested from coastal estuaries and sounds. However, during heavy rain these surface waters routinely receive effluent containing fecal waste of residential, municipal, agricultural or wildlife origin in storm discharges. Each year this surface water contamination contributes to the continued occurrence of molluscan shellfish-associated gastroenteritis. Consequently site selection is the most important pre-harvest food safety decision commercial fisherman and aquaculturists make prior to harvesting or raising molluscan shellfish. Concerns about typhoid fever (Salmonella typhi) associated with shellfish consumption prompted the initiation of the National Shellfish Sanitation Program (NSSP) in the US in the 1950s. Participating state agencies monitor shellfish rearing areas for evidence of fecal contamination and determine sites where shellfish can be harvested. When fecal waste is detected in growing areas, the area is closed to shellfish harvesting. Similar programs are in place within the European Economic Community, and Australia. Although these programs have not eliminated the occurrence of shellfish-related illness, they have reduced the overall incidence of shellfish-associated gastrointestinal infections. When typhoid is now diagnosed in the US the infections are generally travel-related. Indeed, S. typhi, hepatitis A, Norwalk-like viruses (NLV) and other pathogens that often contaminate shellfish are noted on traveler's health alerts for Puerto Rico and the other Caribbean islands. Puerto Rico is a self-governed commonwealth of the US with a population of almost four million. In addition to Puerto Rico's four million residents, each year more than 1.3 million cruise-line patrons and 9.05 million vacationers who arrive by air visit the islands' on-shore restaurants and markets. The project will focus on estimating the potential risk of exposure to enteric pathogens when consuming molluscan shellfish in Puerto Rico, assessing consumer and vendor understanding of the risks of raw shellfish consumption, development of refined consumer and vendor education materials focused on shellfish consumption and conducting a workshop to introduce workers to the techniques available for enhancing shellfish sanitation.</p>
<p>APPROACH: The project will include field studies to estimate the prevalence of noroviruses and other enteric pathogens in molluscan shellfish harvested in Puerto Rican and markets, consumer surveys, development of consumer education materials and the training of laboratory workers in shellfish sanitation techniques. The studies will focus on a total of 12 sites that will be sampled bimonthly for one year and after 5 storm events. Standard National Shellfish Sanitation Program protocols will be used to conduct a descriptive shoal survey of each site, and point sources will be documented. Water, sediment and bivalve samples will be obtained from the primary areas from which bivalves are harvested for human consumption; West coast: a) Boqueron Bay; North coast: b) San Juan Bay, c) Arecibo Bay; South coast: d) Guanica Bay, e) Jobos Bay and, f) the island of Vieques off of the south east coast. Standard sampling protocols developed by ISSC described in the NSSP Guide for the Control of Molluscan Shellfish Model Ordinance will be used to conduct a survey of primary shellfish rearing areas. These standardized protocols focus on the detection of indicator enteric bacteria in shellfish. Market shellfish will also be purchased from vendors and examined for norovirus, hepatitis A virus and Salmonella. Isolates obtained from market shellfish will be phenotypically and genotypically compared with isolates obtained from coastal stations. The proposed studies will provide a temporal and spatially diverse picture of the distribution of enteric pathogens in coastal waters and molluscan shellfish beds. Vendor and consumer knowledge of the risk posed by consuming raw shellfish will also be evaluated. Surveys will be conducted of consumers, restaurant workers, and vendor attitudes about shellfish consumption by conducting pre and post educational intervention surveys at retail markets over a two-year period. The survey instrument will employ a combination of Likert scale and dichotomous response options. Individual questions will focus on personal knowledge of the risks associated with shellfish consumption and sources of information accessed by the respondent. Confidence intervals for the difference between proportions will be calculated to compare pre and post survey responses. The survey information collected will be used by a panel of consumer education and extension specialists to develop new outreach materials for consumers. Alternative drafts of developed consumer education materials will be pre-tested prior to distribution. To improve shellfish sanitation monitoring expertise A combined classroom and field-based workshop will be developed and conducted in Puerto Rico to provide participants with the information needed to develop, and implement an effective shellfish sanitation program. The workshops will be designed for federal, state and municipal employees with a basic background in biology and some college training. Workshop information will be posted on the project web site, and we will also provide links to information provided by other agencies.</p>