The Role of Asymptomatic and Presymptomatic in Spread of COVID-19

(Updated 4/1/20) In CDC's MMWR articles, they provide evidence in the difficulty for control of COVID-19 with people who are asymptomatic or presymptomatic.  These people do not have symptoms but are infected and can spread the virus.

In a US study, they looked at two nursing homes in Washington state in early March.  

A "facility-wide testing identified a 30.3% prevalence of infection among residents, indicating very rapid spread, despite early adoption of infection prevention and control measures. Approximately half of all residents with positive test results did not have any symptoms at the time of testing, suggesting that transmission from asymptomatic and presymptomatic residents, who were not recognized as having SARS-CoV-2 infection and therefore not isolated, might have contributed to further spread. Similarly, studies have shown that influenza in the elderly, including those living in SNFs, often manifests as few or atypical symptoms, delaying diagnosis and contributing to transmission (6–8). "

Another study in Singapore was posted.  "Investigation of COVID-19 cases in Singapore identified seven clusters (clusters A–G) in which presymptomatic transmission likely occurred. These clusters occurred during January 19–March 12, and involved from two to five patients each (Figure). Ten of the cases within these clusters were attributed to presymptomatic transmission and accounted for 6.4% of the 157 locally acquired cases reported as of March 16."

This enforces the need for social distancing, handwashing, and frequent cleaning, but also tracing personal contact with people who are ill.   As in this case with the nursing home, social distancing can be an issue in addition to having a population that is high at risk.

One interesting note sited in the MMWR report - "Speech and other vocal activities such as singing have been shown to generate air particles, with the rate of emission corresponding to voice loudness (7). News outlets have reported that during a choir practice in Washington on March 10, presymptomatic transmission likely played a role in SARS-CoV-2 transmission to approximately 40 of 60 choir members.*"

CDC MMWR
https://www.cdc.gov/mmwr/volumes/69/wr/mm6913e1.htm
Asymptomatic and Presymptomatic SARS-CoV-2 Infections in Residents of a Long-Term Care Skilled Nursing Facility — King County, Washington, March 2020
Early Release / March 27, 2020 / 69

In the Time of COVID-19, Customer Safety Sells

Food retailers including farmers’ markets are working to comply with new guidance on selling product.  Some have moved to some combination of online ordering, pre-order via phone, pre-packed pickup only, or delivery.   For those that have embraced online ordering with either delivery or pre-packed pickup, they have seen huge increases in sales.  Extension hosted a few local market meetings over the past week, and the anecdotal  evidence suggests that for those operations that have fully adopted and communicated COVID safety measures, business has been good....safety sells.

A butcher in Philadelphia that had focused a good portion of their business on supplying the foodservice channel has moved to a delivery, pre-order pickup model.  With good fortune, they had been experimenting with online and had to rush to get it in place for this pandemic.  They have seen record sales over the past days.  They sold to the regular retail customers but also had a number of new customers.  Another Farmers’ Market in SE PA had also moved to online.  They had pre-order pickup and sales were brisk.

But for many, they will have to work out of the traditional model where shoppers will come to the site to purchase and these operations will adopt the state guidance.  One traditional market reported that sales were down, but regular customers did come out.  They had rudimentary safety systems in place including spacing and hand disinfectant, but they did not seem that they did not communicate their plan well.  One market manager whose market had not opened wondered if it was worth the effort against the risk of getting themselves or their volunteers sick.

This Week in Mislabeled Products for Week Ending March 28, 2020

Wrong Back Label - Winter Gardens Quality Foods, Inc., is voluntary recalling one of its products: Whole Foods Market Vodka Sauce carrying the lot code 20057, because of an undeclared allergen (Milk).   The recall was initiated following a customer complaint regarding the incorrect back label which contained the wrong ingredient and allergen statement.

Sulfites Not Declared - Tiffany Food Corp. of Brooklyn, NY is recalling Huangfushanzen Huang Mountain Tea Mushroom (黄府山珍茶花菇) Dried Mushrooms with UPC 6 943153 804047 and no other coding, because it may contain undeclared sulfites. The recall was initiated after routine sampling by Florida Department of Agriculture and Consumer Services (FDACS) and subsequent analysis revealed the presence of sulfites in Huangfushanzen Huang Mountain Tea Mushroom (黄府山珍茶花菇) Dried Mushrooms which were not declared on the label at a level that could cause a life-threatening reaction in sulfite-sensitive individuals.

Another Recall of Enoki Mushrooms from Korea Due to Listeria

Guan’s Mushroom Co of Commerce, CA is recalling all cases of its 200g/7.05 ounce packages of Enoki Mushroom (Product of Korea) because it has the potential to be contaminated with Listeria monocytogenes,  The potential for contamination was noted after routine testing by State of California revealed the presence of Listeria monocytogenes in 200g package of Enoki.  This comes 10 days after another recall was issued for Enoki mushrooms from Korea by a California company.

https://www.fda.gov/safety/recalls-market-withdrawals-safety-alerts/guans-mushroom-co-recalls-enoki-because-possible-health-risk
Guan’s Mushroom Co Recalls Enoki Because of Possible Health Risk
Summary
Company Announcement Date:  March 23, 2020
FDA Publish Date:  March 23, 2020
Product Type: Food & Beverages
Reason for Announcement:  Potential Listeria monocytogenes  Foodborne Illness
Company Name: Guan's Mushroom Co.
Brand Name:  Guan's Mushroom Co.
Product Description:  Enoki Mushroom

FDA to Provide Flexibility on Nutritional Labeling for Foodservice Items Sold as Retail Items

FDA issued a temporary allowance during the COVID-19 emergency that allows for the sale of food without proper nutritional labeling.  So this could be food or ingredients that a restaurant has that they can now sell as a retail item, or items intended for sale in the foodservice channel from a manufacturer but now want to move it through retail sales.

So nutrition labeling does not need to be on these items during this time, but the items still have to have:

• a statement of identify
• an ingredient statement,
• the name and place of the business of the food manufacturer, packer, or distributor,
• net quantity of contents, and
• allergen information required by the Food Allergen Labeling and Consumer Protection Act

This is a great in helping get food that is in the foodservice channel sold to consumers.

https://www.fda.gov/food/cfsan-constituent-updates/fda-provides-temporary-flexibility-regarding-nutrition-labeling-certain-packaged-food-response-covid

Center for Food Safety and Applied Nutrition
Constituent Update
FDA Provides Temporary Flexibility Regarding Nutrition Labeling of Certain Packaged Food in Response to the COVID-19 Pandemic
March 26, 20202

NIH - Study Looks at Stability of COVID-19 Virus in the Environment

A study in New England Journal of Medicine provided information on the stability of the COVID-19 virus, or SARS-VoV-2, in the environment.

From the report below, "SARS-CoV-2 remained active on plastic and stainless steel surfaces for two to three days under the conditions in this experiment. It remained infectious for up to 24 hours on cardboard and four hours on copper. The virus was detectable in aerosols for up to three hours. These times will vary under real-world conditions, depending on factors including temperature, humidity, ventilation, and the amount of virus deposited."

So basically, there are many factors that come into play regarding stability of this virus including temperature and humidity.  What this does show is that the virus can survive in the environment so actions like hand washing and frequent disinfecting of high contact surfaces are important mitigation practices.

https://www.nih.gov/news-events/nih-research-matters/study-suggests-new-coronavirus-may-remain-surfaces-days
March 24, 2020
Study suggests new coronavirus may remain on surfaces for days

FDA Says Food Supply Safe and Strong in Light of COVID-19

FDA released a statement saying the food supply is safe and solid despite some local shortages during this COVID-19 pandemic.  The statement does not provide any significant new information.  Of course, the food industries are recognized as 'critical infrastructure and "workers in the food and agriculture sector – including those working in agricultural production and food processing of both human and animal food, distribution, retail and food service, and allied industries – are named as essential critical infrastructure workers who are vital to community continuity and resilience."

"If an employee is confirmed to have COVID-19, employers should inform workers of their possible exposure while maintaining confidentiality. Employees exposed to a co-worker with confirmed COVID-19 should follow the Centers for Disease Control and Prevention’s guidance: What to do if you are sick with coronavirus disease 2019 (COVID-19). Employers should consult with their local health department for additional guidance."

https://www.fda.gov/news-events/fda-voices-perspectives-fda-leadership-and-experts/fda-offers-assurance-about-food-safety-and-supply-people-and-animals-during-covid-19
FDA Offers Assurance About Food Safety and Supply for People and Animals During COVID-19

CDC Provides Alert on Ongoing E. coli Outbreak Linked to Clover Sprouts

CDC issues a food safety alert for an E. coli outbreak linked to clover sprouts.  To this point, there have been 39 cases in six states (Iowa, Illinois, Missouri, Texas, Florida, and Utah).  On March 16, 2020, Chicago Indoor Garden recalled all products containing red clover sprouts
.

CDC
https://www.cdc.gov/media/releases/2020/s0319-food-safety-alert-e-coli.html
Food Safety Alert Regarding a Multistate Outbreak of E. Coli

This Week in Mislabeled Product for Week Ending March 21, 2020

Wrong Package - Lindt & Sprüngli (USA) Inc. of Stratham, New Hampshire, is issuing a voluntary recall of one lot of its Lindt Excellence 85% Cocoa chocolate bars due to the bars being wrapped in the wrong packaging. The bars are labeled as Excellence 85% Cocoa, but contain Lindt Excellence Dark Caramel Sea Salt bars, therefore the package does not contain accurate information about allergens - milk and soy.

Label Misses Wheat - Raw Seafoods, Inc is recalling  Wegmans branded Ginger Salmon Oven Safe Meal and Salmon Teriyaki Oven Safe Meal due to undeclared wheat.