Physical proximity may increase COVID-19 risk for poultry plant workers

A study published today in the Centers for Disease Control and Prevention's (CDC's) Morbidity and Mortality Weekly Report (MMWR) highlights factors that may increase the risk of infection with SARS-CoV-2, the virus that causes COVID-19, among US poultry facility workers—especially those who are foreign-born.

Higher risk of COVID-19 for those processing meat and poultry has been associated with physical proximity, shared equipment, and structural and social inequalities within the employee population.

Researchers with the Maryland Department of Health and the CDC administered a survey to 359 employees working in two Maryland poultry processing facilities over a 2-day period in May. Workers were queried about their activities and exposure risks for contracting SARS-CoV-2 during the week preceding the interview. Foreign-born workers, including immigrants and refugees, represented 37.8% of the overall total, 65.9% of whom were from Haiti.

Foreign-born workers were more likely to work in fixed locations on the production floor in cutup and packaging roles than US-born workers (odds ratio [OR], 4.8; 95% confidence interval [CI], 2.3 to 10.0). The authors note that these positions are considered high risk because of proximity to other workers and association with higher risk of COVID-19 transmission in other meat processing facilities.

Foreign-born employees were also more likely than US-born workers to report shared commutes (45.2% vs 29.9%), and were six times more likely to live with other poultry workers (OR, 6.0; 95% CI, 3.7 to 9.5). They were less likely to report participation in social gatherings in the week before the survey, were more likely to report wearing a mask during shared commutes, and reported fewer visits to businesses than US-born workers.

"Engineering and administrative controls might reduce SARS-CoV-2 transmission risk for workers on the production floor, many of whom are foreign-born," the study authors wrote. "Culturally and linguistically tailored messages should be disseminated about mitigation measures, particularly those pertaining to carpools and close living quarters."
Dec 17 MMWR study

Study: Delaying COVID-19 tracheostomy does not reduce risk for doctors

A study in JAMA Otolaryngology-Head & Neck Surgery today evaluated the timing of tracheostomy to open a COVID-19 patient's airway and found that early tracheostomy was associated with improvement in some outcomes and did not contribute to increased risk of infection for clinicians.

Tracheostomy— a surgical opening in a patient's neck to accommodate a breathing tube that delivers oxygen to the lungs—is often performed for patients undergoing prolonged mechanical ventilation, including COVID-19 patients.

The infectivity of SARS-CoV-2, was initially thought to mirror that of the virus responsible for the previous SARS epidemic in China, with maximal infectiousness around day 7 to 10 after symptom onset. Early in the COVID-19 pandemic, scientists and physicians followed 2003 CDC SARS guideline that recommended against tracheostomy during this period to avoid infection risk for clinicians.

Researchers at a tertiary-care medical center in New York City evaluated 148 critically ill patients (120 men and 28 women; mean age 58.1 years) with confirmed COVID-19 infections who received mechanical ventilation and tracheostomy from Mar 1 to May 7. Tracheostomy was performed by interventional pulmonologists and head and neck surgeons at the patient's bedside in the intensive care unit.

Early tracheostomy was defined as occurring prior to 10 days after endotracheal intubation—placement of a breathing tube through the windpipe via the mouth or nose. Tracheostomy was considered late if it occurred at day 10 after intubation or later.

The timing of tracheostomy was significantly associated with length of stay, with patients who underwent early tracheostomy discharged from the hospital 40 days after admission versus 49 days for those who underwent late tracheostomy (median difference, -8; 95% CI, -15 to -1).

None of the three pulmonologists who performed tracheostomy at the facility contracted COVID-19. Of the larger otolaryngology staff of 35 at the facility, 6 contracted COVID-19 but had not performed tracheostomies before becoming infected.

"These data demonstrate that with thoughtful selection of patients, there is no countervailing evidence to recommend categorically delaying tracheostomy in this patient population," the study authors concluded.
Dec 17 JAMA Otolaryngol Head Neck Surg study

CDC says waterborne diseases cause 6,600 deaths a year in US

Infections caused by 17 waterborne pathogens cause approximately 7.15 million illnesses and 6,630 deaths (0.9% case mortality) across the United States each year, report CDC researchers in Emerging Infectious Diseases yesterday. The most common diseases were otitis externa (65.3% of cases), norovirus infections (18.6%), giardiasis (5.8%), and cryptosporidiosis (4.5%).

The researchers excluded diseases caused by water-adjacent pathogens like malaria, algal toxins, and chemical exposures. Other waterborne diseases with insufficient data, such as sapovirus and rotavirus, were also not included.

Using data from 2000 through 2015 and the 2014 US population, statistical modeling, and structured expert judgment, the researchers found that otitis externa caused 94.3% of emergency department treat-and-release visits for waterborne-transmitted diseases. Nontuberculous mycobacteria (NTM) infection, otitis externa, and Pseudomonas pneumonia caused 43.6%, 19.7%, and 13.1% of waterborne disease hospitalizations, respectively.

Pseudomonas septicemia had the highest cost per hospital stay ($38,200) followed by Legionnaires' disease ($37,300). The most cumulative costs were incurred by NTM infection ($1.53 billion), otitis externa ($564 million), and Pseudomonas pneumonia ($453 million).

The researchers also classified the study's waterborne diseases into primarily respiratory and enteric illnesses, finding that 5,530 (83.4%) of the deaths were from respiratory-related illness compared with 131 (2.0%) of enteric illnesses. When compared with a 2011 Emerging Infectious Diseases study, waterborne diseases had a lower burden on the enteric system than foodborne disease, possibly because water treatment is made to prevent enteric illness.

Overall, waterborne diseases caused more illness than foodborne diseases if nonspecified agents were excluded.

"This analysis highlights the expanding role of environmental pathogens (e.g., mycobacteria, Pseudomonas, Legionella) that can grow in drinking water distribution systems; plumbing in hospitals, homes, and other buildings; recreational water venues; and industrial water systems (e.g., cooling towers)," write the CDC researchers.
Dec 16 Emerg Infect Dis study

BARDA adds more monkeypox-smallpox vaccine to federal stockpile

Bavarian Nordic yesterday announced that the US Biomedical Advanced Research and Development Authority (BARDA) has exercised an option to buy more of its new monkeypox and smallpox vaccine. BARDA is part of the US Department of Health and Human Services.

The option is part of a $200 million order for the vaccine, called Jynnoes, that was awarded in April. The first $106 million covered the production of bulk vaccine and supply of liquid-frozen doses. With the new option, BARDA is spending $83 million to buy more bulk vaccine with $12 million earmarked for more liquid-frozen doses that will be made at the company's new fill-and-finish facility.

The vaccine was approved in 2019 as the first vaccine approved for monkeypox and the first for a non-replicating smallpox vaccine. Supplies of the vaccine are placed in the Strategic National Stockpile for use when needed by front-line responders to a bioterrorism incident or lab accident.
Dec 16 Bavarian Nordic press release
May 1 CIDRAP News scan "BARDA contract adds monkeypox-smallpox vaccine to federal stockpile"

Fatal H5N6 avian flu case reported in China

China recently reported a fatal H5N6 avian flu case involving an 81-year-old woman from Jiangsu province, Hong Kong's Centre for Health Protection (CHP) said in a Dec 11 statement.

The woman worked as a farmer and had been exposed to live chickens at her home before her symptoms began on Nov 16. She was hospitalized and then died from her infection on Nov 27.

Mainland China has now reported 25 human H5N6 cases since 2014, 8 of them fatal. Though H5N6 outbreaks in birds have been reported in China and a number of other Asian countries, human infections have been reported only in China.

The country reported its last case in August 2019 in a woman from Beijing.
Dec 11 CHP statement
Aug 19, 2019, CIDRAP News scan "China reports H5N6 avian flu infection in Beijing woman"