When someone talks about having “the stomach flu,” they are probably describing acute-onset gastroenteritis caused by one of the noroviruses, which are members of the “calcivirus” family (Caliciviridae).[1] Noroviruses are entirely unrelated to influenza viruses.[2]

The Centers for Disease Control and Prevention (CDC) estimates that noroviruses cause nearly 21 million cases of acute gastroenteritis annually, making noroviruses the leading cause of gastroenteritis in adults in the United States. Norovirus is highly contagious and transmitted by infected individuals at an enormous rate. It is simple genetically and evolves quickly, and exposure does not lead to lasting immunity. It is estimated that each individual experiences norovirus five times during the course of their life. On average, norovirus also causes roughly 109,000 hospitalizations and 900 deaths each year in the United States, mostly among adults aged 65 and older (CDC).[3]

Nature has created an ingenious bug in norovirus. The round blue ball structure of norovirus is actually a protein surrounding the virus’s genetic material. [4]  The virus attaches to the outside of cells lining the intestine, and then transfers its genetic material into those cells. Once the genetic material has been transferred, norovirus reproduces, finally killing the human cells and releasing new copies of itself that attach to more cells of the intestine’s lining. 

The virus, due to its structure, is also very stable in the environment and is resistant to many sanitizers/disinfectants. It is a major concern for several sectors including health care, education, and tourism, and in food, shellfish, and produce. But most foodborne norovirus outbreaks occur in restaurants or institutional food service settings.

How Common is Norovirus?

    Currently, norovirus is the most common cause of acute gastroenteritis in the United States.[5] While bacterial causes of foodborne illness, such as pathogenic Escherichia coli and Salmonella, are often cited as commonly reported sources of food poisoning, noroviruses cause 58% of foodborne illnesses acquired in the U.S. Thus, norovirus is the leading cause of outbreaks from contaminated food in this country. According to CDC estimates, this translates into about 2,500 reported norovirus outbreaks in the United States each year. Norovirus outbreaks occur throughout the year but are most common from November to April. About 1 in every 15 individuals in the U.S. will get norovirus illness annually. By five years of age, one out of every 14 children will visit an emergency room, and one out of 278 children will be hospitalized due to norovirus.

    Norovirus outbreaks have been reported in many settings, including healthcare facilities, restaurants and catered events, schools, and childcare centers.[6] Cruise ships account for a small percentage (1%) of reported norovirus outbreaks overall.

    Sources of Norovirus and Challenges Associated with the Virus

    In addition to humans, norovirus can infect a broad range of hosts including livestock, pets, and wild animals (e.g., marine mammals and bats). Little is known about norovirus infections in most non-human hosts, but the close genetic relatedness between some animal and human noroviruses, coupled with a lack of understanding of where newly appearing human norovirus genotypes and variants are emerging from, has led to the hypothesis that norovirus may not be host restricted and might be able to jump the species barrier. To date, no animal noroviruses have been detected in human stool, but some serological evidence hints to possible transmission from animals to humans.

    In humans, norovirus is transmitted primarily through the fecal-oral route, with as few as 10 to 100 virion particles needed to initiate infection. Transmission occurs either person-to-person or through contamination of food or water. It can also transmit through several other means such as droplets of vomit and fomites (surfaces contaminated with either feces or vomit) contaminated with norovirus. The infection spreads mainly among the people in crowded and enclosed places such as schools, shelters, hotels, resorts, nursing homes, cruise ships, and airline flights, even those of short duration. The probability of norovirus infections is increased among the people with compromised immune systems, as well as people following unhygienic practices. 

    Historically, food is the most common vehicle of transmission for noroviruses; of 232 outbreaks of norovirus between July 1997 and June 2000, 57% were foodborne, 16% were spread from person-to-person, and 3% were waterborne. When food is the vehicle of transmission, contamination occurs most often through a food handler improperly handling a food directly before it is eaten.

    How is norovirus transmitted?

    Norovirus outbreaks can result from the evolution of one strain due to the pressure of population immunity. Typically, norovirus outbreaks are dominated by one strain, but they can also involve more than one strain. Although the GII.4 genotype drove most outbreaks worldwide for two decades, a newer strain—GII.17—became the predominant cause of U.S. norovirus outbreaks during the 2024–2025 season (CDC). For example, some outbreaks associated with shellfish have been found to contain up to seven different norovirus strains. Swedish outbreak studies also reveal a high degree of genetic variability, indicating a need for wide detection methods when studying these outbreaks.[7]

    Once infected, individuals begin viral shedding in stool and vomitus as soon as eight hours after exposure, with viral shedding peaking four days after exposure and, in some instances, continuing for up to 56 days. Given the high titers produced during viral shedding and the low number of norovirus particles that are needed to establish infection, it is possible that one individual could potentially infect thousands.[8]

    Although norovirus-infected individuals shed the highest number of viral particles while they are ill, asymptomatic shedding is also possible for a short period of time before the onset of symptoms. Concentrations of shed norovirus particles are high both for symptomatic and asymptomatic infected individuals, and peak titers of shedding usually occur during the first five days after infection.

    Food handlers and health-care workers are considered important contributing factors in the spread of norovirus both in foodborne outbreaks and in person-to-person transmitted outbreaks occurring in healthcare institutions. Several case reports have confirmed the role of infected food handlers in causing outbreaks, and the percentage of outbreaks in which food handlers were involved has been reported to be as high as 34% to 70%. In healthcare settings, nosocomial (hospital-acquired) norovirus transmission is mainly caused by symptomatic shedders, but asymptomatic transmission is not uncommon.[9]

    Role of Restaurants

    Food service establishments are routinely linked to foodborne illness outbreaks, and out of the over 9,000 foodborne illness outbreaks reported to the CDC between 1998 to 2004 (a vast underestimation of disease burden), over half (52%) were associated with restaurants or delicatessens.[10] Not surprisingly, noroviruses were identified in almost half of the foodborne outbreaks when a specific cause was determined, and restaurants were by far the most common setting/source for these outbreaks (64%). These findings have led the CDC and others to call upon the food service industry to instigate preventive measures and policies to curtail norovirus transmission in their facilities.[11]

    Yet noroviruses are especially difficult to manage once introduced into a retail foodservice or grocery facility. Sometimes described as the “perfect human pathogen,” these viruses are able to last for up to two weeks on surfaces, are resistant to most commercially available disinfectants, and are easily spread by touch. Only a few virus particles are needed to make someone sick. In the case of a retail food setting, the presence of a single norovirus-infected staff member or customer can, within hours, lead to numerous cases of disease in the local population. Logistically, this results in staff absences, temporary closures of facilities for disinfection, and the need to dispose of potentially contaminated food, although there are also broader impacts such as legal expenses and damage to brand.[12]

    The history of norovirus outbreaks has led the CDC and others to call upon the restaurant industry to instigate preventive measures and policies to curtail norovirus transmission in their facilities including handwashing, cleaning, and sanitizing, and implementing employee health policies.

    Symptoms & Risks of Norovirus Infection

    The most common symptoms are sudden onset of vomiting and watery diarrhea, although stomach cramps and pain also often occur. Some people experience fever and body aches. Symptoms usually start 12 to 48 hours after being exposed and typically last about 1 to 3 days.[13]

    Although symptoms usually only last 1 to 2 days in healthy individuals, norovirus infection can become quite serious in children, the elderly, and immune-compromised individuals. In some cases, severe dehydration, malnutrition, and even death can result from norovirus infection, especially among children, and among older and immune-compromised adults in hospitals and nursing homes. 

    Diagnosing a Norovirus Infection

    Diagnosis of norovirus illness is based on the combination of symptoms, particularly the prominence of vomiting, fever, and short duration of illness. If a known norovirus outbreak is in progress, public health officials may obtain specimens from ill individuals for testing in a lab.[14] Lab tests consist of identifying norovirus under an electron microscope. A reverse transcriptase polymerase chain reaction test (RT-PCR assay) can also detect norovirus in food, water, stool samples, and on surfaces. These tests isolate and replicate the suspected virus’s genetic material for analysis. An ELISA can also be performed, which detects antigens; they are easier to perform than RT-PCR, but less sensitive and can also result in many false negatives.

    Treating a Norovirus Infection

    Collecting a stool sample and using molecular methods to find viral RNA is the preferred method to test for norovirus in the public health world. In many cases, however, diagnosis is made based on symptoms. Most people who become ill recover within 24 to 48 hours after symptoms with just rest and fluids to prevent dehydration. Antibiotics are not effective, as the illness is caused by a viral pathogen.[15]

    There is no specific treatment available for norovirus. In most healthy people, the illness is self-limiting; however, outbreaks among infants, children, elderly, and immune-compromised populations may result in severe complications among those affected. Death may result without prompt measures. A vital part of therapy for norovirus is the replacement of fluids and minerals such as sodium, potassium, and calcium—otherwise known as electrolytes—lost due to persistent vomiting and diarrhea. This rehydration can be done either by drinking large amounts of liquids, or intravenously.

    Preventing Norovirus Infection

    The role of food handlers has been documented substantially, highlighting that keeping ill food handlers out of the kitchen coupled with proper handwashing is the best strategy to prevent norovirus. Outbreaks linked to infected restaurant staff in the past have led to multiple meals served from the same kitchen causing illness. In a 2006 outbreak in Michigan, the investigation revealed that several foodservice workers had been ill and continued to work, ultimately leading to environmental contamination and persistence when a line cook had vomited in the restaurant. At least 364 restaurant patrons became ill with gastroenteritis consistent with norovirus. The investigation also identified deficiencies with employee handwashing practices, cleaning, and sanitizing of food and nonfood contact surfaces.

    The good news about norovirus is that it does not multiply in foods as many bacteria do. In addition, thorough cooking destroys the virus. To avoid norovirus, make sure the food you eat is cooked completely. While traveling in areas that have polluted water sources, raw vegetables should be washed thoroughly before being served, and travelers should drink only boiled drinks or carbonated bottled beverages without ice.[16]

    Shellfish (i.e., oysters, clams, mussels) pose the greatest risk, and any particular serving may be contaminated with norovirus; there is no way to detect a contaminated oyster, clam, or mussel from a safe one. Shellfish become contaminated when their waters become contaminated—e.g., when raw sewage is dumped overboard by recreational or commercial boaters. Shellfish are filter feeders and will concentrate virus particles present in their environment. With shellfish, only complete cooking offers reliable protection; steaming does not kill the virus or prevent its transmission. Some researchers suggest that norovirus monitoring in shellfish areas could be a good preventive strategy. Waterborne norovirus outbreaks are ubiquitous, but difficult to recognize. Improved analysis of environmental samples would have the potential to significantly improve the detection of norovirus in shellfish waters.[17]

    [1]           Tripathi, M., & Kumar, S. (2019). Developments of an Emerging Infectious Agent: Norovirus. Annual Research & Review in Biology, 31(4), 1-6. https://doi.org/10.9734/arrb/2019/v31i430054

    [2]           Desai AN. (2019). What Is Norovirus? JAMA. 322(20):2032.

    [3]           “Updated Norovirus Outbreak Management and Disease Prevention Guideline.” Centers for Disease Control and Prevention, 4 Mar 2011. Available at: https://www.cdc.gov/mmwr/preview/mmwrhtml/rr6003a1.htm.

    [4]           Kallem, S., & Bigback, K. (2005, September 1). Caliciviridae. Retrieved September 07, 2020, from https://web.stanford.edu/group/virus/calici/2005kallem/caliciviridae.html

    [5]           Chikara Ogimi, Yae Jean Kim, Emily T Martin, Hee Jae Huh, Cheng-Hsun Chiu, Janet A Englund, What’s New With the Old Coronaviruses?, Journal of the Pediatric Infectious Diseases Society, Volume 9, Issue 2, June 2020, Pages 210–217, https://doi.org/10.1093/jpids/piaa037

    [6]           “Common Settings of Norovirus Outbreaks.” Centers for Disease Control and Prevention, 8 Oct 2020. Available at: https://www.cdc.gov/norovirus/trends-outbreaks/outbreaks.html.

    [7]           Lopman B, et al. (2012). Environmental transmission of norovirus gastroenteritis. Curr Opin Virol. 2(1):96-102.

    [8]           Marsh Z, et al. (2018). Epidemiology of Foodborne Norovirus Outbreaks – United States, 2009-2015. Food Safety. 6(2):58-66.

    [9]           Lopman B, Simmons K, Gambhir M, Vinjé J, Parashar U. (2014). Epidemiologic implications of asymptomatic reinfection: a mathematical modeling study of norovirus. Am J Epidemiol. 179(4):507-12.

    [10]         Hall AJ, Wikswo ME, Pringle K, Gould LH, Parashar UD. (2014). Vital Signs: Foodborne Norovirus Outbreaks – United States, 2009-2012. MMWR. 63(22):491-5.

    [11]         Sabrià A, et al. (2016). Norovirus shedding among food and healthcare workers exposed to the virus in outbreak settings. J Clin Virol. 82:119-25.

    [12]         Kosa KM, Cates SC, Hall AJ, Brophy JE, Fraser A. (2014) Gaps in Food Safety Professionals’ Knowledge about Noroviruses. J Food Prot. 77(8):1336-41.

    [13]         “Facts About Noroviruses.” Centers for Disease Control and Prevention, 15 Oct 2018. Available at: https://www.cdc.gov/nceh/vsp/pub/Norovirus/Norovirus.htm.

    [14]         Hall AJ, et al. (2011). Updated Norovirus Outbreak Management and Disease Prevention Guidelines. MMWR. 60(RR03):1-15.

    [15]         “Norovirus infection.” Mayo Clinic, 5 Feb 2020. Available at: https://www.mayoclinic.org/diseases-conditions/norovirus/symptoms-causes/syc-20355296.

    [16]         Lopman B, et al. (2012). Environmental transmission of norovirus gastroenteritis. Curr Opin Virol. 2(1):96-102

    [17]         “Facts About Noroviruses.” Centers for Disease Control and Prevention, 15 Oct 2018. Available at: https://www.cdc.gov/nceh/vsp/pub/Norovirus/Norovirus.htm.

    Update: February 19, 2026

    On February 18, 2026, the FDA expanded the list of oysters harvested in British Columbia, Canada that may be contaminated with norovirus. 

    FDA now advises restaurants not to serve, food retailers not to sell, and consumers not to eat oysters harvested between December 22, 2025 and February 4, 2026 from BC 17-20 CLF #1401656 by Stellar Bay Shellfish Ltd., Canada. These oysters were sold under the following brand names: Kusshi, Chrome Point, Stellar Bay, and Stellar Bay Gold.

    Updated Advisory: FDA Advisory for Oysters from British Columbia that are Potentially Contaminated with Norovirus

    Original post: February 13, 2026

    Between January 18, 2026 and February 2, 2026, 11 people from 5 different meal parties in Washington State reported norovirus-like illness symptoms after consuming raw oysters harvested from a specific growing area in British Columbia, Canada. 

    The United States Food and Drug Administration (FDA) is advising restaurants and retailers not to serve or sell these oysters and advising consumers not to eat them. 

    Washington State Case Information

    Eleven people from 5 separate meal parties reported norovirus-like symptoms after consuming raw oysters from British Columbia, Canada harvest area BC 17-20 #1401656. The exposures occurred between January 17, 2026 and February 1, 2026. 

    Advice to Consumers

    • If purchasing oysters, ask the retailer where they were harvested. Do not purchase oysters harvested from British Columbia, Canada harvest area BC 17-20 #1401656 with original harvest dates from December 22, 2025 to February 4, 2026. These oysters were sold under the following brand names: Kusshi, Chrome Point, Stellar Bay, and Stellar Bay Gold. 
    • If you purchased oysters recently, contact your retailer to find out where they were harvested. If you are unable to determine where the oysters were harvested, discard them. 

    Advice to Retailers

    Do not sell or serve the following Stellar Bay Shellfish Ltd. oysters:

    • Kusshi, Chrome Point, Stellar Bay, or Stellar Bay Gold brand oysters harvested from British Columbia, Canada harvest area BC 17-20 (Nanoose Bay) CLF #1401656 with original harvest dates from December 22, 2025 to February 4, 2026.

    About Norovirus

    Norovirus is a viral infection spread through direct contact with someone infected with norovirus, eating food or drinking liquid contaminated with norovirus, or touching objects or surfaces contaminated with norovirus. Shellfish can be contaminated with norovirus if they are grown in contaminated water. 

    Symptoms of Norovirus Infection

    Symptoms typically appear 12 to 48 hours after exposure and can include: 

    • Vomiting
    • Watery diarrhea 
    • Abdominal cramps
    • Muscle aches
    • Headache
    • Fever
    • Chills

    Most people feel better in 1 to 2 days but they can spread infection to others while they are sick and after their symptoms resolve. 

    Prevention

    • Wash hands with soap and water after going to the bathroom, changing diapers, and before eating or preparing food.
    • Cook shellfish thoroughly and wash fruits and vegetables.
    • If you are sick with norovirus-like symptoms, stay home from work and do not cook food for others while you have symptoms and for at least 3 days after you recover. 
    • Clean and disinfect contaminated surfaces and wash laundry in hot water (see Resources below for detailed cleaning instructions).

    The Utah Department of Agriculture and Food (UDAF) Division of Regulatory Services, the Utah Department of Health and Human Services, and Utah County Health Department are investigating a norovirus outbreak in Utah county that has been linked to frozen half shell oysters imported from the Republic of Korea. On July 24, the U.S. Food and Drug Administration (FDA) issued a recall of Korean frozen half shell oysters from Designated Area No. 1 harvested between December 30, 2024 and February 6, 2025. UDAF is expanding this recall to include all oysters from this area harvested through August 6, 2025.

    UDAF is advising restaurants and retailers to not serve or sell, and consumers not to eat, any Korean frozen half shell oysters from Designated Area No. 1 harvested between December 30, 2024 and August 6, 2025. At this time, UDAF is aware that product that was recalled in July was distributed to restaurants in Cache, Davis, Salt Lake, and Utah counties and product may have been distributed to additional counties. This is an ongoing investigation and UDAF is working with local, state, and federal partners to ensure a safe food supply and safeguard public health. This advisory is issued due to new evidence of product contamination beyond the initial FDA recall parameters.

    Background: FDA Recall

    On July 24, 2025, the U.S. Food and Drug Administration (FDA) issued a recall of Korean frozen half shell oysters from Designated Area No. 1 with the following details:

      • Certification Number: KR-15-SP
      • Harvest Dates: December 30, 2024 – February 6, 2025
      • Lot Codes: B250103, B250106, B250112, B250114, B250119, B250121, B250123, B250130, B250108, B250116, B250206
      • FDA Advisory: FDA Recall Notice

    New Norovirus Detection: On August 18, 2025, UDAF was notified that an additional lot of frozen half shell oysters tested positive for norovirus:

      • Certification Number: KR-15-SP
      • Harvest Date: February 13, 2025
      • Harvest Area: Designated Area No. 1
      • Lot Code: B250213

    This newly identified contaminated lot falls outside the FDA’s original advisory, prompting UDAF to expand the warning to include all frozen half shell oysters from this harvest area and date range.

    Norovirus Information: Symptoms typically appear 12–48 hours after exposure and may include:

      • Nausea
      • Vomiting
      • Diarrhea
      • Stomach cramps
      • Fever and headache (in some cases)

    Most people recover within 1–3 days, but vulnerable groups, such as young children, older adults, and individuals with weakened immune systems may experience more severe illness. Anyone who has eaten these oysters and develops symptoms should contact their healthcare provider and report the illness to igotsick.health.utah.gov. People who are sick should not prepare food for others until at least 48 hours after symptoms stop.

    Ongoing Investigation: This advisory is part of a collaborative investigation with local health departments, the Utah Department of Health and Human Services (DHHS), and the FDA. Further updates will be provided at ag.utah.gov as new information becomes available. To report a concern, please contact UDAF’s Division of Regulatory Services at (801) 982-2220.

    FDA Advises Restaurants and Retailers Not to Serve or Sell and Consumers Not to Eat Certain Frozen, Raw, Half-shell Oysters from Republic of Korea Potentially Contaminated with Norovirus

    Audience

    • Restaurants and food retailers in Arizona (AZ), California (CA), Colorado (CO), Montana (MT), and Utah (UT) that have purchased frozen, raw, half-shell oysters with lot code: B250112, harvested from Designated Area No. 1 in the Republic of Korea (ROK) on Jan. 12, 2025, and processed by JBR KR-15-SP in Tongyeong-si, ROK.  
       
    • Consumers in AZ, CA, CO, MT, and UT who have purchased frozen, raw, half-shell oysters with lot code: B250112, harvested from Designated Area No. 1 in the Republic of Korea (ROK) on Jan. 12, 2025, and processed by JBR KR-15-SP in Tongyeong-si, ROK. 

    Product

    • Certain frozen, raw, half-shell oysters processed by JBR KR-15-SP, harvested on Jan. 12, 2025, from harvest area Designated Area No. 1 in the Republic of Korea (ROK).  The implicated products include Lot Code: B250112. The frozen, raw, half-shell oysters were distributed to restaurants and retailers in AZ, CA, CO, MT, and UT and may have been distributed to other states as well. 

      The photo below is included for reference as an example of product tag/label that would be included on cartons of frozen, raw, half-shell oysters with Lot Code: B250112.

     Purpose

    Wang Globalnet of Vernon, CA has recalled frozen, raw, half-shell oysters with Lot Code: B250112, harvested from Designated Area No. 1 in the Republic of Korea (ROK) on Jan. 12, 2025 and processed by JBR KR-15-SP in Tongyeong-si, ROK because they may be contaminated with norovirus.  The FDA is advising consumers not to eat and restaurants and food retailers not to serve or sell and to dispose of these frozen, raw, half-shell oysters that were distributed in AZ, CA, CO, MT, and UT, and may have been distributed to other states as well.

    Shellfish, such as oysters, contaminated with norovirus can cause illness if eaten, and potentially severe illness in people with compromised immune systems. Food containing norovirus may look, smell, and taste normal. Consumers of these products who are experiencing symptoms of illness should contact their healthcare provider and report their symptoms to their local Health Department. Diarrhea, abdominal cramps, nausea, vomiting, and fever may be associated with gastroenteritis infections caused by this organism.

    Symptoms of Norovirus

    People of all ages can get infected and sick with norovirus. The most common symptoms of norovirus are diarrhea, vomiting, nausea, and stomach pain. Other symptoms include fever, headache, and body ache.

    A person usually develops symptoms 12 to 48 hours after being exposed to norovirus. Most people with norovirus illness get better within 1 to 3 days.

    If you have norovirus illness, you can feel extremely ill, and vomit or have diarrhea many times a day. This can lead to dehydration, especially in young children, older adults, and people with other illnesses. Symptoms of dehydration include decrease in urination, dry mouth and throat, and feeling dizzy when standing up. Children who are dehydrated may cry with few or no tears and be unusually sleepy or fussy.

    If you think you or someone you are caring for is severely dehydrated, call your healthcare provider.

    Summary of Problem and Scope

    On July 16, 2025, the Utah Department of Agriculture and Food informed the FDA of an outbreak of norovirus illnesses associated with consumption of certain oysters from the Republic of Korea with Lot Code: B250112 harvested from Designated Area No. 1 in the ROK on Jan. 12, 2025, and processed by JBR KR-15-SP in Tongyeong-si, ROK.  The product was recalled by  Wang Globalnet of Vernon, CA on July 21, 2025.

    FDA Actions

    The FDA is issuing this alert advising restaurants and food retailers not to serve or sell and consumers not to eat frozen, raw, half-shell oysters with Lot Code: B250112, harvested from Designated Area No. 1 in the Republic of Korea (ROK) on Jan. 12, 2025, and processed by JBR KR-15-SP in Tongyeong-si, ROK, and distributed in AZ, CA, CO, MT and UT, due to possible norovirus contamination.  The FDA is awaiting further information on distribution of these frozen, raw, half-shell oysters and will continue to monitor the investigation and provide assistance to state authorities as needed.  As new information becomes available, the FDA intends to update the safety alert.  

    Recommendations for Restaurants and Retailers

    Restaurants and retailers should not serve or sell the potentially contaminated frozen, raw, half-shell oysters. Restaurants and retailers should dispose of any products by throwing them in the garbage or contacting their distributor to arrange for destruction.

    Restaurants and retailers should also be aware that shellfish may be a source of pathogens and should control the potential for cross-contamination of food processing equipment and the food processing environment. Their employees should follow the steps below:

    • Wash hands with warm water and soap following the cleaning and sanitation process.
    • Retailers, restaurants, and other food service operators who have processed and packaged any potentially contaminated products need to be concerned about cross-contamination of cutting surfaces and utensils through contact with the potentially contaminated products.
    • Retailers that have sold bulk product should clean and sanitize the containers used to hold the product.
    • Regular frequent cleaning and sanitizing of food contact surfaces and utensils used in food preparation may help to minimize the likelihood of cross-contamination.

    California based S&M Shellfish Co. has issued a product recall for oysters after confirming multiple illnesses due to norovirus contamination. The oysters affected were sold under the names Fanny Bay, Buckley Bay and Royal Miyagi Oysters and were harvested between December 1st and 9th in British Columbia. 

    California restaurants and businesses affected by the recall include San Francisco’s Waterbar, San Francisco’s Mission Street Oyster Bar, Redwood City’s Hurrica, Santa Rosa’s Santa Rosa Seafood and San Pablo’s Mariscos La Playita, according to a notice from the California Department of Public Health. The oysters were also distributed in Arizona, Colorado, Washington, D.C., Florida, Georgia, Hawaii, Illinois, Kentucky, Missouri, Nevada, New Jersey, New York, North Carolina and Pennsylvania.

    The U.S. Food & Drug Administration is recommending businesses dispose of these products or return them to their distributor for destruction. The oysters can be identified by the original harvesters or producers, printed on the shellfish tag: Pacific Northwest Shellfish and Union Bay Seafood.

    Washington company Rudy’s Shellfish also recently issued a recall of oysters and Manila clams harvested from Nov. 15 to Dec. 11 due to a norovirus outbreak. The affected shellfish were distributed in California as well as other states.

    More than 70 people reported feeling ill after eating oysters at the LA Times’ 101 Best Restaurants event in Los Angeles on Dec. 3, according to L.A. Taco. The Los Angeles County Department of Public Health is investigating a norovirus outbreak associated with the oysters served at “an event on December 3,” a spokesperson told L.A. Taco without referring to the LA Times party specifically. An LA Times spokesperson told L.A. Taco that the oysters served at the event were Fanny Bay Oysters originating from British Columbia and sourced by Santa Monica Seafood.

    The Desert Sun reported this week that there have been 57 confirmed and probable cases of norovirus reported by people who ate raw oysters from British Columbia at California restaurants, according to the CDPH. 

    Norovirus symptoms include diarrhea, vomiting, nausea, stomach pain, fever, headache and body ache, according to the FDA. Symptoms usually develop between 12 and 48 hours after exposure and last one to three days. 

    af-bug-mast

    In October 2024, Public Health Seattle King County (PHSKC) officials investigated an outbreak of norovirus associated with McDonald’s Restaurant located at 8515 124th Ave NE in Kirkland, WA. Three people who did not know each other reported illness after eating at the restaurant between October 23 and October 26, 2024. No one was hospitalized and no one died. Two of the three people who became sick underwent testing. Both people tested positive for norovirus.

    PHSKC visited the restaurant on October 29, 2024 and confirmed that no restaurant workers reported being sick in the past two weeks. Investigators did not find any unsafe food practices related to the spread of PHSKC revisited the restaurant on November 1, 2024, and asked them to follow their norovirus cleaning protocols and complete a deep cleaning of the restaurant.

    The Pierce County Department of Health announced that it was working with Harvest Buffet, 3121 S. 38th St., Tacoma, following a suspected norovirus outbreak. We closed the restaurant around 10 a.m. Thursday, Oct. 10, and will reopen it after at least 24 hours. Staff will clean and sanitize the restaurant and take all steps necessary to ensure the public is no longer at risk.

    Multiple people in the same group but from different households reported norovirus-like symptoms on Wednesday after they ate at the restaurant Sunday, Oct. 6. The meal was their only common source of food.

    If you ate at Harvest Buffet recently and became ill, contact us at food@tpchd.org, report online, or (253) 649-1696. 

    Norovirus is highly contagious. It can cause diarrhea and vomiting, often at the same time. Symptoms typically last a day or two. It is the same virus often related to cruise ship outbreaks.

    In addition to cleaning and sanitizing the restaurant, staff will throw out all ready-to-eat foods like vegetables, bread, and cheese.

    Cleaning for norovirus

    Clean vomit or diarrhea accidents immediately.

    Step 1. Remove vomit or poop.

    • Pick up the chunks with paper towels or other disposable material. Wear disposable gloves if available. 
    • Soak up liquids with absorbent materials. Use kitty litter or dry oatmeal for carpeted areas.
    • Double bag and discard.
    • Do not use a vacuum cleaner.

    Step 2. Sanitize areas where vomit or poop was present, as well as bathroom surfaces and other things you frequently touch. 

    • Disinfect hard surfaces using 1 2/3 cups of household bleach per gallon of water. Allow for 1 minute of contact time.
    • Sanitize all handles and knobs in your house with the bleach solution.
    • Linens (including clothing, towels, napkins): Wash separately in hot water and dry on high.
    • Steam clean carpets using the highest setting for heat.
    • Avoid cross-contamination (use separate sanitation cloths for bathroom and other surfaces).
    • Clean and disinfect all containers used (e.g., buckets).

    Handwashing

    Wash hands often with soap and warm water for at least 20 seconds. Especially after cleaning, restroom use, and before eating.

    If you ate at Harvest Buffet and became ill, contact the Health Department at food@tpchd.org, report online, or call (253) 649-1696.

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    The DLNR Division of State Parks (DSP), in consultation with the Hawai‘i Dept. of Health (DOH), has elected to close the entire Kalalau Trail section, from Kē‘ē to Honopu in the Nāpali Coast State Wilderness Park. DLNR and DOH are closely coordinating the situation in Kalalau and taking appropriate action to ensure public health and safety.

    The highly contagious norovirus has been identified as the cause of illness to dozens of backpackers along the trail. This viral illness typically causes copious vomiting, often accompanied by fever, abdominal cramps, and diarrhea.

    The closure is effective immediately and DOH is recommending closure at least until Sept. 19. All comfort stations along the trail are being cleaned and disinfected. Ha‘ena State Park and Kē‘ē Beach will remain open with enhanced cleaning and disinfection of the comfort station there.

    Officers from the DLNR Division of Conservation and Resources Enforcement (DOCARE) will travel to Kalalau, Hanakoa, and Hanakāpīʻai this weekend to direct any remaining permitted and unpermitted hikers and campers to leave the area. The Kalalau Trailhead at Kē‘ē will be manned by law enforcement 24/7 to prevent entrance onto the trail.

    DOH has received reports of illness from at least 37 people who were hiking the Kalalau Trail and camping at a state campsite at Kalalau beach, though the actual number of affected people is estimated to be higher. A DOH team is at Kalalau today collecting  water, soil, and environmental swabs to assess ongoing risk of transmission from contaminated surfaces or water.

    Norovirus was detected in multiple samples from people who didn’t directly interact with each other.

    Beginning with the initial closure Wednesday morning and again yesterday, DOCARE officers flew into Kalalau to tell campers they needed to leave. Officer Christian “Kana‘i” Gayagas said he and a fellow officer approached about 40 campers at Kalalau. They cited two, who did not have the required permit to hike beyond Hanakāpīʻai.

    Forrest Liss of Kaua‘i backpacked  to Kalalau on Tuesday, prior to the park closure. He said he’d heard about some sort of illness on social media and spoke while cleaning camp, preparing to hike out. He said by the time he and his party reached camp most everyone who was sick had already left. He added, “We figure camping, people get sick. Maybe they drank the water. People get sick but when they start going through the protocols of shutting down the park, actually this is something a little more serious.”

    Norovirus has impacted at least three other popular trails in the U.S. in recent years.

    The National Park Service Office of Public Health has received increasing reports of gastrointestinal (GI) illnesses among hikers and other individuals along the Appalachian Trail in areas of Georgia, Tennessee and North Carolina. Norovirus is suspected as the cause of illness and has been confirmed diagnostically in at least some of the cases. The impact of norovirus in other areas and states along the Appalachian Trail is possible due to virus transmissibility and challenges to hand hygiene and sanitation along the trail.

    According to media reports, dozens of people visiting Havasu Falls in Arizona got ill and were flown out for medical treatment in June. Norovirus was confirmed as the cause of sickness in some cases. According to the Centers for Disease Control, in 2022, the largest outbreak of acute gastroenteritis documented in the Grand Canyon National Park backcountry occurred. At least 222 rafters and backpackers became infected, probably with norovirus. Also, in 2022 and again this past April, hikers on the Pacific Coast Trail also reported getting sick.

    Coincidentally, Thursday had been scheduled as a regular DSP maintenance day at Kalalau. In addition to the DOCARE officers, three state parks workers collected and bagged rubbish to be helicoptered out of the valley. They did two “sling loads,” which is dramatically different from a decade ago when it was common for helicopters to lift dozens of 600-pound sling loads of trash out of Kalalau.

    In addition to that work and replacing missing signs, they employed DOH recommendations when cleaning the camp’s comfort station. Derrick Louis of DSP said, “We swept the floor and bleached the whole bathroom, floors, railings, toilets, everything. Waited at least 7 to10 minutes, cleaned everything and did it again and then we wiped everything down with a disinfectant.”

    Despite the current closure, Kalalau Valley has a long history of harboring squatters who are often hidden in the thick forest of the valley making them undetectable.

    Commercial and recreational boaters should not drop people off to swim, paddle, or kayak to Kalalau beach. It is imperative to keep humans out based on the DOH protocols. People can be cited or arrested during the closure, and once Kalalau reopens if they are present without a required state permit.

    San Diego County health officials have linked 11 confirmed and probable cases of norovirus illness to frozen oysters imported from South Korea. 

    Customers who ate the oysters at 100s Seafood Grill Buffet in Mission Valley between March 31 and April 1 became sick, one person went to the emergency department.  

    The U.S. Food & Drug Administration (FDA) is now linking the San Diego illnesses to quick-frozen oysters.  

    The FDA is cautioning all restaurants and stores that sell frozen, raw half-shell oysters to check their freezers and verify the origin of their oysters.  To identify their origin, look for shellfish tag or label information. Oysters processed by JBR (KR 15 SP) in Tongyeongsi, Republic of Korea on 11/27/2023, 1/4/2024 and 2/15/2024 with lot numbers B231126, B240103 and B240214 should not be consumed. The County of San Diego is working with the California Department of Public Health to identify other potential retailers in our region. 

    These items may be labeled “Amazing Sea Brand.” 

    If you have consumed these oysters and feel ill, it is important to see your doctor for evaluation,” said Wilma Wooten, M.D., M.P.H., County Public Health Officer. “If you or someone you live with is sick with norovirus, it is important to wash your hands often and clean common areas to prevent spreading the infection.” 

    This comes four months after County of San Diego health officials linked 41 confirmed and probable cases of norovirus to raw oysters imported from a specific harvest location in Northwest Mexico. 

    People infected with norovirus generally develop nausea, vomiting, diarrhea, stomach cramps, fever and body aches approximately 12 to 48 hours after consuming contaminated foods. The illness typically lasts for one to three days. The vomiting and diarrhea can lead to dehydration requiring medical attention, especially in young children, older adults and people with other illnesses.   

    The County’s Epidemiology Program and Department of Environmental Health and Quality are working closely with California Department of Public Health, including the Shellfish Program, to continue investigating illnesses associated with oysters.   

    To report illness to the County after dining out or purchasing from wholesale food locations call (858) 505-6814, or email fhdepi@sdcounty.ca.gov.

    Audience

    Restaurants and food retailers in Connecticut (CT), Florida (FL), Georgia (GA), Maine (ME), Maryland (MD), Massachusetts (MA), Minnesota (MN), New Jersey (NJ), Ohio (OH), Rhode Island (RI), South Carolina (SC) and Texas (TX) that have recently purchased oysters from Norm Bloom and Son (CT-069-SS, AQ), harvested from Westport, CT, lot 207, with the harvest date 2/20/2024.

    Consumers in CT, FL, GA, MA, MD, ME, MN, NJ, OH, RI, SC, and TX who have recently purchased oysters from Norm Bloom and Son (CT-069-SS, AQ), harvested from Westport, CT, lot 207, with the harvest date 2/20/2024.

    Product

    Recalled oysters are from Norm Bloom and Son (CT-069-SS, AQ), harvested from Westport, CT, lot 207, with the harvest date 2/20/2024. The oysters were distributed to restaurants and retailers in CT, FL, GA, MA, MD, ME, MN, NJ, OH, RI, SC, and TX, and may have been distributed to other states as well.

    Purpose

    The FDA is notifying restaurants, food retailers, and consumers that the Connecticut Department of Agriculture, Bureau of Aquaculture is conducting a recall of oysters harvested by Norm Bloom and Son (CT-069-SS, AQ) from Westport, CT, lot 207, with the harvest date 2/20/2024, because they are associated with a norovirus outbreak in Minnesota and may be contaminated with norovirus. The FDA is advising restaurants and food retailers not to serve or sell and consumers not to eat the recalled oysters.

    Shellfish contaminated with norovirus can cause illness if eaten, and potentially severe illness in people with compromised immune systems. Food containing norovirus may look, smell, and taste normal. Consumers of these products who are experiencing symptoms of illness should contact their healthcare provider and report their symptoms to their local Health Department. Diarrhea, abdominal cramps, nausea, vomiting, and fever may be associated with gastroenteritis infections caused by this organism.

    Symptoms of Norovirus

    People of all ages can get infected and sick with norovirus. The most common symptoms of norovirus are diarrhea, vomiting, nausea, and stomach pain. Other symptoms include fever, headache, and body ache.

    A person usually develops symptoms 12 to 48 hours after being exposed to norovirus. Most people with norovirus illness get better within 1 to 3 days.

    If you have norovirus illness, you can feel extremely ill, and vomit or have diarrhea many times a day. This can lead to dehydration, especially in young children, older adults, and people with other illnesses. Symptoms of dehydration include decrease in urination, dry mouth and throat, and feeling dizzy when standing up. Children who are dehydrated may cry with few or no tears and be unusually sleepy or fussy.

    If you think you or someone you are caring for is severely dehydrated, call your healthcare provider

    Summary of Problem and Scope

    The Connecticut Department of Agriculture, Bureau of Aquaculture is conducting a recall of oysters from Norm Bloom and Son (CT-069-SS, AQ), harvested from Westport, CT, lot 207, with the harvest date 2/20/2024, because they are associated with a norovirus outbreak in Minnesota and may be contaminated with norovirus. The oysters were distributed to restaurants and retailers in CT, FL, GA, MA, MD, ME, MN, NJ, OH, RI, SC, and TX, and may have been distributed to other states as well. The FDA is advising consumers not to eat, and restaurants and food retailers not to sell, and to dispose of these oysters.

    Contaminated oysters can cause illness if eaten raw, particularly in people with compromised immune systems. Food contaminated with norovirus may look, smell, and taste normal. Consumers of these products who are experiencing symptoms of norovirus illness should contact their healthcare provider, who should report their symptoms to their local Health Department.

    FDA Actions

    The FDA is sharing the notice of the CT oyster recallExternal Link Disclaimer and advising consumers not to eat, and restaurants and food retailers not to sell, oysters from Norm Bloom and Son (CT-069-SS, AQ), harvested from Westport, CT, lot 207, with the harvest date 2/20/2024, and distributed to restaurants and retailers in  CT, FL, GA, MA, MD, ME, MN, NJ, OH, RI, SC, and TX. The FDA is awaiting information on further interstate distribution of the oysters and will continue to monitor the investigation and provide assistance to state authorities as needed.

    Recommendations for Restaurants and Retailers

    Restaurants and retailers should not serve or sell the potentially contaminated oysters. Restaurants and retailers should dispose of any products by throwing them in the garbage or returning them to their distributor for destruction.

    Restaurants and retailers should also be aware that shellfish may be a source of pathogens and should control the potential for cross-contamination of food processing equipment and the food processing environment. They should follow the steps below:

    • Wash hands with warm water and soap following the cleaning and sanitation process.
    • Retailers, restaurants, and other food service operators who have processed and packaged any potentially contaminated products need to be concerned about cross-contamination of cutting surfaces and utensils through contact with the potentially contaminated products.
    • Retailers that have sold bulk product should clean and sanitize the containers used to hold the product.
    • Regular frequent cleaning and sanitizing of food contact surfaces and utensils used in food preparation may help to minimize the likelihood of cross-contamination.