Active environmental surveillance of SARS-CoV-2 in Midwestern United States meatpacking plants.

This pilot project investigated environmental SARS-CoV-2 presence in seven Midwestern meatpacking plants from May 2020 to January 2021. This study investigated social distancing and infection control practices and incorporated environmental sampling of surfaces and air in employee common areas. All plants increased their social distancing efforts, increased the frequency of cleaning and disinfecting worker areas, and screened for symptomatic people to prevent entry into the workplace. 575 samples from common areas were collected and evaluated with RT-qPCR for the presence of SARS-CoV-2. 42/367 surface samples were positive, while no virus was detected in air samples. Case positive data from the counties surrounding each plant showed peak positive SARS-CoV-2 cases from 12-55 days before the virus was detected in the plant, indicating that environmental sampling is likely a lagging indicator of community and plant infection.

Invisible No More: The Impact of COVID-19 on Essential Food Production Workers.

From the farms to the packing plants, essential workers in critical food production industries keep food on our tables while risking their and their families' health and well-being to bring home a paycheck. They work in essential industries but are often invisible. The disparities illuminated by COVID-19 are not new. Instead, they are the result of years of inequities built into practices, policies, and systems that reinforce societal power structures. As a society, we are now at an antagonizing moment where we can change our collective trajectory to focus forward and promote equity and justice for workers in agriculture and food-related industries. To that end, we describe our experience and approach in addressing COVID-19 outbreaks in meat processing facilities, which included three pillars of action based on public health ethics and international human rights: (1) worksite prevention and control, (2) community-based prevention and control, and (3) treatment. Our approach can be translated to promote the health, safety, and well-being of the broader agricultural workforce.

Use of Vinegar and Water to Identify COVID-19 Cases During a Workplace Entrance Screening Protocol.

OBJECTIVE: To evaluate an empirical olfactory test to identify COVID-19 cases during a workplace entrance screening. METHOD: An active screening for olfactory dysfunction using water and vinegar was conducted in April to June 2020 among 4120 meat packing workers in Latin America. RESULTS: The sensitivity and specificity of the active olfactory screening examination were 41.2% and 85.3%, respectively, using reverse transcription polymerase chain reaction (RT-PCR) tests as a gold standard. 10.6% of employees who tested positive for COVID-19 had an olfactory dysfunction as their only symptom. These individuals would not have been identified with standard workplace screening measures including temperature screening. CONCLUSION: Active screening for olfactory dysfunction may serve as a valuable tool to both identify potential COVID-19 infections and exclude those who do not have infection and should be a part of parallel algorithm combined with standard workplace entrance screening procedures.

Characteristics of SARS-CoV-2 Transmission among Meat Processing Workers in Nebraska, USA, and Effectiveness of Risk Mitigation Measures.

The coronavirus disease (COVID-19) pandemic has severely impacted the meat processing industry in the United States. We sought to detail demographics and outcomes of severe acute respiratory syndrome coronavirus 2 infections among workers in Nebraska meat processing facilities and determine the effects of initiating universal mask policies and installing physical barriers at 13 meat processing facilities. During April 1-July 31, 2020, COVID-19 was diagnosed in 5,002 Nebraska meat processing workers (attack rate 19%). After initiating both universal masking and physical barrier interventions, 8/13 facilities showed a statistically significant reduction in COVID-19 incidence in <10 days. Characteristics and incidence of confirmed cases aligned with many nationwide trends becoming apparent during this pandemic: specifically, high attack rates among meat processing industry workers, disproportionately high risk of adverse outcomes among ethnic and racial minority groups and men, and effectiveness of using multiple prevention and control interventions to reduce disease transmission.

CD163 and pAPN double-knockout pigs are resistant to PRRSV and TGEV and exhibit decreased susceptibility to PDCoV while maintaining normal production performance.

Porcine reproductive and respiratory syndrome virus (PRRSV) and transmissible gastroenteritis virus (TGEV) are two highly infectious and lethal viruses causing major economic losses to pig production. Here, we report generation of double-gene-knockout (DKO) pigs harboring edited knockout alleles for known receptor proteins CD163 and pAPN and show that DKO pigs are completely resistant to genotype 2 PRRSV and TGEV. We found no differences in meat-production or reproductive-performance traits between wild-type and DKO pigs, but detected increased iron in DKO muscle. Additional infection challenge experiments showed that DKO pigs exhibited decreased susceptibility to porcine deltacoronavirus (PDCoV), thus offering unprecedented in vivo evidence of pAPN as one of PDCoV receptors. Beyond showing that multiple gene edits can be combined in a livestock animal to achieve simultaneous resistance to two major viruses, our study introduces a valuable model for investigating infection mechanisms of porcine pathogenic viruses that exploit pAPN or CD163 for entry.

Pig epidemics are the biggest threat to the pork industry. In 2019 alone, hundreds of billions of dollars worldwide were lost due to various pig diseases, many of them caused by viruses. The porcine reproductive and respiratory virus (PRRS virus for short), for instance, leads to reproductive disorders such as stillbirths and premature labor. Two coronaviruses ­ the transmissible gastroenteritis virus (or TGEV) and the porcine delta coronavirus ­ cause deadly diarrhea and could potentially cross over into humans. Unfortunately, there are still no safe and effective methods to prevent or control these pig illnesses, but growing disease-resistant pigs could reduce both financial and animal losses. Traditionally, breeding pigs to have a particular trait is a slow process that can take many years. But with gene editing technology, it is possible to change or remove specific genes in a single generation of animals. When viruses infect a host, they use certain proteins on the surface of the host's cells to find their inside: the PRRS virus relies a protein called CD163, and TGEV uses pAPN. Xu, Zhou, Mu et al. used gene editing technology to delete the genes that encode the CD163 and pAPN proteins in pigs. When the animals were infected with PRRS virus or TGEV, the non-edited pigs got sick but the gene-edited animals remained healthy. Unexpectedly, pigs without CD163 and pAPN also coped better with porcine delta coronavirus infections, suggesting that CD163 and pAPN may also help this coronavirus infect cells. Finally, the gene-edited pigs reproduced and produced meat as well as the control pigs. These experiments show that gene editing can be a powerful technology for producing animals with desirable traits. The gene-edited pigs also provide new knowledge about how porcine viruses infect pigs, and may offer a starting point to breed disease-resistant animals on a larger scale.

COVID-19 Outbreak Among Employees at a Meat Processing Facility - South Dakota, March-April 2020.

On March 24, 2020, the South Dakota Department of Health (SDDOH) was notified of a case of coronavirus disease 2019 (COVID-19) in an employee at a meat processing facility (facility A) and initiated an investigation to isolate the employee and identify and quarantine contacts. On April 2, when 19 cases had been confirmed among facility A employees, enhanced testing for SARS-CoV-2, the virus that causes COVID-19, was implemented, so that any employee with a COVID-19-compatible sign or symptom (e.g., fever, cough, or shortness of breath) could receive a test from a local health care facility. By April 11, 369 COVID-19 cases had been confirmed among facility A employees; on April 12, facility A began a phased closure* and did not reopen during the period of investigation (March 16-April 25, 2020). At the request of SDDOH, a CDC team arrived on April 15 to assist with the investigation. During March 16-April 25, a total of 929 (25.6%) laboratory-confirmed COVID-19 cases were diagnosed among 3,635 facility A employees. At the outbreak's peak, an average of 67 cases per day occurred. An additional 210 (8.7%) cases were identified among 2,403 contacts of employees with diagnosed COVID-19. Overall, 48 COVID-19 patients were hospitalized, including 39 employees and nine contacts. Two employees died; no contacts died. Attack rates were highest among department-groups where employees tended to work in proximity (i.e., <6 feet [2 meters]) to one another on the production line. Cases among employees and their contacts declined to approximately 10 per day within 7 days of facility closure. SARS-CoV-2 can spread rapidly in meat processing facilities because of the close proximity of workstations and prolonged contact between employees (1,2). Facilities can reduce this risk by implementing a robust mitigation program, including engineering and administrative controls, consistent with published guidelines (1).