Raw oysters are prized as a delicacy, but they also carry serious risks if mishandled. Because oysters filter large volumes of water, they can accumulate harmful bacteria and viruses such as Vibrio, Pseudomonas, and norovirus. To reduce those dangers, strict federal and state rules including harvest tags, refrigeration requirements, and use-by limits govern every step from harvest to restaurant plate. These safeguards are not just red tape. They are critical public-health protections that, when ignored, can lead to devastating illnesses, amputations, or even death.

Food Safety and Oyster Handling: Why Standards Matter 

Strict rules govern the harvesting, handling, and serving of oysters. Both federal law and state health codes (including California) require that oysters carry a Shellfish Tag that accurately lists the harvest date, lot number, and harvest location. These tags are not just paperwork, they are critical safeguards that allow distributors, restaurants, and regulators to ensure oysters are safe to eat. 

Industry standards further emphasize that: 

• Harvest dates must remain accurate and unaltered as oysters move through the supply chain. Standards such as distributors not selling oysters more than a week old or restaurants not serving oysters more than 7, 10 or 14 days old cannot be maintained if dates are inaccurate.
• Time and temperature must be carefully controlled to prevent bacteria from multiplying. 

When these standards are not followed, the consequences can be devastating. 

An Example of What Can Go Wrong – Schneider Wallace’s Recent Oyster Illness Case 

Schneider Wallace Cottrell Kim obtained a multi-million dollar settlement for a man whose left arm was amputated at the shoulder after developing necrotizing fasciitis (flesh-easting infection) after eating raw oysters. 

In this case, the oysters were repeatedly mislabeled with incorrect harvest dates. Our client dined at a California restaurant where they were served raw oysters from shipments that had a harvest date repeatedly rewritten to make the oysters seem fresher. Harvested one day before a holiday, but labeled as harvested the day after the holiday.  Tags then entered incorrectly, moving the harvest date forward again. When repackaged by distributors, new tags moved the date yet again. The harvester, initial distributor and a 2nd distributor all mislabeled lots of oysters, and the multiple changes to the harvest date ultimately hid a week of time. Standards the companies had for how fresh oysters must be to accept and resell or distribute were made irrelevant by a cascade of false harvest dates. 

Shortly after eating them, the diner began experiencing severe symptoms: chills, fever, and gastrointestinal illness. Within days, the infection progressed rapidly, ultimately leading to a flesh-eating bacterial condition known as necrotizing fasciitis. Emergency surgery was required, including the amputation of an arm, to save the individual’s life. 

Medical testing confirmed the presence of harmful bacteria commonly associated with spoiled oysters. Experts concluded that the age and mishandling of the shellfish were a substantial factor in causing the illness. 

The case demonstrates how a single breakdown in food safety protocols can cascade into catastrophic harm. The settlement we achieved reflects not only the seriousness of our client’s injuries but also the broader responsibility of food distributors and restaurants to ensure strict compliance with safety regulations. 

Live Oysters: How They’re Tracked and Tagged from Water to Plate 

In the U.S., live oysters (“shellstock”) move under a uniform framework called the National Shellfish Sanitation Program (NSSP). Every sack/box must carry a waterproof tag so regulators can trace any illness back to the exact harvest area and date; restaurants must keep those tags on file for 90 days after the last shellfish from that container is sold or served. 

At Harvest (Harvester Tag) 

A licensed harvester (or aquaculture grower) attaches a durable, waterproof tag before leaving the harvest area. At minimum under the NSSP, that tag lists: the harvester’s ID, date of harvest, the most precise growing-area designation practicable, and the type/quantity of shellstock, plus the bold statement directing retailers to keep the tag for 90 days. States may add more fields (e.g., time of harvest), but those are the national minimums. 

At the First Certified Dealer (Dealer Tag) 

When shellstock reaches a certified dealer (shucker-packer, reshipper, etc.), the dealer tag rides with the lot through commerce. It must include the dealer name/address, certification number(s), harvest date (or date of depuration/wet-storage), species/quantity, the same 90-day tag-retention statement (with a line for retailers to fill in the date the last shellfish was sold/served), consumer advisory, and “Keep Refrigerated.” 

If shellstock is re-containered (e.g., broken down from a master sack), the new container must be retagged with all required dealer-tag information, and the original harvester tag must be retained for 90 days. Consumers are put at risk when this information is missing or incorrectly retagged, as occurred in one case Schneider Wallace handled. 

What California Operators Must Do 

California adopts the NSSP framework and explicitly requires that shellstock tags stay attached to the container until it’s empty, and that the source identity be maintained for 90 days in chronological order correlated to the date(s) of sale or service. (This is what enables rapid traceback if illnesses are reported.) 

Health Risks from Raw Oysters: Vibrio, Pseudomonas, and Norovirus 

Raw oysters can carry naturally occurring marine bacteria, most notably Vibrio species, and can also concentrate human enteric viruses like norovirus from contaminated waters. Illness ranges from gastroenteritis to sepsis, necrotizing (flesh-eating) wound infections, limb loss, and death. This is especially a risk in people with liver disease, diabetes, immunosuppression, or open wounds. 

1) Vibrio Bacteria 

• What it is: Vibrio live naturally in coastal and brackish waters; oysters filter and can concentrate the bacteria. The main oyster food illness associated species are V. parahaemolyticus (typically gastroenteritis) and V. vulnificus (can cause rapidly progressive bloodstream and wound infections). 
• Symptoms & severity:
  • V. parahaemolyticus: acute diarrhea, abdominal cramps, nausea/vomiting, fever; severe disease is less common but possible in high-risk patients
  • V. vulnificus: primary septicemia after eating raw oysters, or as necrotizing wound infection after seawater exposure. Many patients require intensive care or limb amputation. 1 in 5 die, sometimes within 24–48 hours of symptom onset.
• Why controls matter: Warmer temperatures accelerate Vibrio growth; the NSSP requires tight time-to-temperature controls from harvest through distribution to keep bacterial levels down.

2) Pseudomonas Bacteria (Spoilage Pathogen) 

• What it is. A bacteria best known for opportunistic infection (lungs, blood, wounds) in healthcare settings; a possible but rarer illness type for oysters and shellfish. Pseudomonas can be detected in oysters and is often associated with spoilage of seafood. Spoilage and the risks of spoilage increase dramatically with temperature and time. 
• Risk profile. Documented oyster-related foodborne disease from Pseudomonas are less common but do occur; the concerns are (a) quality/spoilage when counts are high, and (b) wound/soft-tissue infection from marine water exposure in susceptible individuals. 

3) Norovirus (Common Cause of Oyster-linked Outbreaks) 

• What it is. A highly contagious human virus; oysters can bioaccumulate norovirus when waters are contaminated (e.g., sewage overflows, ill food handlers at wet-storage sites). Unlike bacteria, norovirus doesn’t multiply in oysters; risk hinges on contamination and inadequate cooking. 
• Symptoms & course. Sudden vomiting, diarrhea, cramps, and low-grade fever 12–48 hours after exposure; illness is usually 1–3 days but can be severe in the elderly, young children, and the immunocompromised. 
• Possible long-term effects. After acute gastroenteritis (including norovirus), a subset of patients develop post-infectious irritable bowel syndrome (PI-IBS), meta-analyses suggest a several-fold increased risk that can persist months to years 

4) Catastrophic Outcomes to be Aware of (Rare but Real) 

• Sepsis and death. V. vulnificus bloodstream infections carry 50% fatality rates if they progress to primary septicemia and can progress rapidly; early recognition and antibiotics are critical.
• Necrotizing (“flesh-eating”) infections & amputations. Typically wound-exposure cases with V. vulnificus, but other bacteria such as pseudomonas can be a source. Tissue damage can necessitate surgical debridement or amputation to control spread and prevent death. 
• Chronic GI symptoms. PI-IBS and other functional GI disorders can follow an acute gastrointestinal infection (including norovirus). 

Recent Shellfish-linked Illness Events (2024–2025) 

California: ~400 gastrointestinal illnesses after raw oysters served across CA Investigators found two concurrent outbreaks attributable to norovirus/other enteric viruses, with one cluster likely contaminated during wet storage away from the original growing area. 

California: State alert after 57 confirmed/probable norovirus cases among diners who ate BC-harvested raw oysters 

Southern California: FDA warned against specific harvest areas in Baja California and Sonora due to norovirus; SoCal counties reported 200+ illnesses during the advisory period. 

National: Importer Sea Win (Los Angeles) recalled 650 cases of frozen half-shell oysters tied to a norovirus outbreak. FDA advised restaurants/retailers not to serve implicated lots. 

National: FDA issued a new advisory against certain frozen raw half-shell oysters distributed to AZ, CA, CO, MT, and UT (potential norovirus). 

Louisiana: Vibrio vulnificus surge with deaths. The Louisiana Dept. of Health reported an unusually high case count and fatalities in 2025: 26 cases and 5 deaths as of Sept 16, 2025 (all hospitalized), prompting a statewide caution about raw seafood/sea-water exposure. Earlier in the season, their department reported 17 cases/4 deaths (through July 31). 

Pacific Northwest
A PSP (saxitoxin) bloom prompted coast-wide closures in Oregon; dozens of illnesses reported, with expanded harvest bans and FDA consumer warnings extending into Washington. (PSP is a toxin in clams, mussels, oysters; cooking or freezing will not neutralize it.) 

Pacific Oysters (Crassostrea gigas): What the Study Shows about Pseudomonas and Vibrio 

A 2009 study on retail-style, refrigerated Pacific oysters ) profiled which microbes dominate over time. It found that in raw oysters at day 0, the leading groups were Pseudomonas (~22%) and Vibrionaceae (~20%).  

During chilled storage, Pseudomonas expanded to ~73% by the end of shelf life, while Vibrionaceae remained at ~20%, i.e., refrigeration slowed growth but did not eliminate Vibrio-family bacteria. The same work showed a broad-spectrum effect of chitosan and an extension of sensory/microbiological shelf life from ~8–9 days to ~14–15 days under those conditions. 

What That Means in Practice 

• Pseudomonas: spoilage driver. Expect off-odors, slime, and loss of quality as storage progresses. 
• Vibrionaceae (includes Vibrio parahaemolyticus / V. vulnificus). Persistence at 20% even under proper refrigeration underscores why time-to-temperature control and verified sourcing are critical; refrigeration alone can’t eliminate Vibrio risk in raw service. 

Legal Liability for Harvesters, Distributors, Resellers, and Retail 

If oysters are held under insanitary conditions (e.g., kept warm beyond required limits) they can be deemed “adulterated” under the Federal Food, Drug, and Cosmetic Act (FD&C Act). If the label or tag is false or misleading (e.g., wrong harvest date/area), the product is “misbranded.” Either violation can trigger regulatory action and bolster civil tort claims. 

Harvester / Grower Responsibilities 

• Accurate harvester tags with harvest date/area and other NSSP-required data; tags must ride with the lot through commerce. False dates or areas = misbranding and undermine traceback efforts.
• Time-to-temperature controls from the moment of harvest (state Vibrio Control Plans under the NSSP). Failure to promptly cool/ice can support an adulteration theory (“held under insanitary conditions”). 

Harvester / Grower Legal Exposure 

Companies that misbrand or adulterate product, and endanger end customers health and lives, can be found negligent, negligence per se (violation of statutes/regs), and, where contamination/temperature abuse renders the food unfit, breach of implied warranty and strict products liability theories may be alleged. In California, negligence per se is codified at Evidence Code § 669 

Certified Dealer, Processor, Distributor Liability 

• Must operate under seafood HACCP (21 C.F.R. Part 123) and the FDA Hazards & Controls Guidance, including receiving from approved sources, verifying time–temperature control, and keeping records. Breakdowns (e.g., warm transport, missing monitoring) are HACCP deviations
• Mislabeling or re-tagging with inaccurate harvest information is misbranding; temperature abuse is adulteration 

Dealer Liability 

Negligence (including negligent transport/cold-chain failures), negligence per se (HACCP or NSSP violations), breach of implied warranty/strict liability if the food is not “fit for ordinary purposes.” (In CA, Commercial Code § 2314 applies; food served for value counts as a “sale.”) 

Retail & Restaurants 

• Food Code duties: cold-hold ≤ 41 °F, maintain consumer advisories for raw/undercooked foods, and date-mark opened ready-to-eat containers (7-day rule).
• Shellstock tag retention for 90 days, in chronological order correlated to sale/serve dates; in California this is explicit in Health & Safety Code § 114039.4. Failure to keep tags obscures traceback and can create new liabilities for the business.

Restaurant Liability 

Negligent handling (e.g., warm raw-bar display), negligence per se for Food Code or Cal Code breaches (depending on local adoption), failure-to-warn or misrepresentation if advisories are missing or tags are inaccurate, and implied warranty or strict liability. 

Liability to the Plaintiff For Oyster Injury 

Ultimately the restaurant, dealers and distributors, and harvesters can be made liable for an injury, due to failures to take due care and follow regulations.  In our recent multi-million dollar settlement, the lawsuit advanced several causes of action: 

• Negligence and Negligence Per Se – for failure to comply with health and safety codes and internal policies regarding oyster handling and accurate harvest date tagging. 
• Strict Products Liability – because the oysters were defective and unfit for safe consumption. 
• Breach of Implied Warranty – as the oysters were not of merchantable quality and failed to meet ordinary consumer expectations. 
• Loss of Consortium – brought on behalf of our client’s spouse, recognizing the profound impact of these injuries on their family life. 

The case underscores the critical importance of compliance with state, federal, and industry standards in the handling of perishable seafood products. 

The Cost of Illness and the Recovery after Eating Unsafe Oysters 

The patient or consumer cost of a food borne illness from oysters can vary dramatically. Norovirus most typically results in short-lived gastroenteritis and time off work; Vibrio parahaemolyticus ranges from outpatient to brief hospitalization; Vibrio vulnificus can require ICU care, multiple surgeries, even amputation, with long rehabilitation and permanent loss. All come with a risk of death, which cannot be eliminated. 

Typical costs a consumer may face after illness: 

• Acute medical care: ED visit, labs/cultures, IV fluids and antibiotics; for severe Vibrio cases, ICU days, vasopressors, surgical debridement, skin grafts, and amputation where necessary. CDC notes that many V. vulnificus patients require intensive care or limb amputation, and about 1 in 5 die, sometimes within 1–2 days. 
• Post-acute & rehab: inpatient rehab, outpatient wound care, prosthetics and prosthetic replacement cycles (if amputation), home health, and adaptive equipment. 
• Medication & follow-up: antibiotics, pain management, infectious-disease/surgery follow-ups. 
• Productivity losses: days to months off work for the patient (and sometimes caregivers). For norovirus, productivity loss is the largest cost. 
• Chronic sequelae: a subset develop post-infectious IBS (PI-IBS) and related functional GI symptoms that can last years, raising ongoing medical and productivity costs. Meta-analyses estimate a ~4–6× higher IBS risk after infectious gastroenteritis 
• Wrongful death–related losses: Loss of financial support where fatalities occur. 

The CDC says that Norovirus costs the U.S. $2 billion per year in total. Vibrio infections can be devastating to the individual household, with one study putting the total loss including medical, and lost productivity at over $4 million per case. 

“What Costs or Damages Should I Document After an Oyster or Other Food Borne Illness”? 

If you have experienced a food borne illness, these are some of the costs you should document and keep track of for reimbursement: 

• Past/future medical expenses (acute through rehab/prosthetics) 
• Lost wages and loss of earning capacity 
• Non-economic damages (pain/suffering; loss of enjoyment) 
• Wrongful death damages where applicable 
• Household/attendant care and home modifications (for amputees and long-term disability) 

Food Illness Law Firm 

Schneider Wallace is known for our aggressive pursuit of injured consumers’ rights through complex litigation and class action lawsuits. To learn more about recovering damages for injuries caused by unsafe food, contact us for a free consultation with our trial lawyers. We practice before state and federal courts in jurisdictions throughout the United States, and have offices in California, Texas, and Washington D.C.