High COVID antibodies noted in public service, especially in jail staff, EMTs

While 10.1% of first responders and public service personnel in New York City reported positive COVID test results, 22.5% had COVID-19–specific antibodies in their blood, with even higher rates in prison staff and emergency medical technicians (EMTs), according to an Emerging Infectious Diseases study yesterday.

The study ran from May 18 through Jul 2, 2020, and included 22,647 participants from correctional facilities, emergency medical services, childcare settings, fire and police departments, and the medical examiner's office. A prior estimate from the same period found that 19.5% of New York City residents tested seropositive, meaning their blood contained antibodies to SARS-CoV-2, the virus that causes COVID-19.

The researchers found that correctional staff and EMTs had the highest rates of seroprevalence at 39.2% and 38.3%, respectively, while laboratory technicians and medicolegal death investigators had the lowest rates, at 10.1% and 10.8%, respectively.

First responders and public safety workers made up 87.9% of the study cohort, and a closer analysis showed that 31.6% of those who performed at least 25 aerosol-generating procedures per shift tested seropositive, compared with the 20.7% who didn't perform any of those procedures. Workers who wore personal protective equipment (PPE) all the time also had higher seropositivity rates, although the researchers say this could be due to higher exposure risks on the job, improper PPE use, insufficient training, or a perceived shortage of supplies.

"These populations face unique challenges when working in congregate or uncontrolled settings and would be a critical population for vaccination and other public health efforts to reduce SARS-CoV-2 infection," the researchers write.

Some individual factors were also associated with antibody likelihood, such as household exposure to someone who had COVID (adjusted odds ratio [aOR], 3.52), black ethnicity (aOR, 1.50), or severe obesity (aOR, 1.31). Location mattered, as well: Borough seroprevalence ranged from 17.4% (Staten Island) to 28.8% (the Bronx).
Jan 25 Emerg Infect Dis study

Cumulative smoking especially associated with more severe COVID-19

People who have smoked for more than 30 pack-years—a unit for cumulative smoking—are about twice as likely to be hospitalized and to die after testing positive for COVID-19 as nonsmokers, according to a research letter published yesterday in JAMA Internal Medicine.

The researchers looked at health records from 7,102 patients who were in Cleveland Clinic's COVID-19 registry from Mar 8 through Aug 25, 2020. Of those, 84.8% had never smoked, 2.4% were current smokers, and 12.8% formerly smoked.

The investigators found that people who had smoked for more than 30 pack-years were 2.25 times more likely to be hospitalized after a positive COVID-19 test (95% confidence interval [CI], 1.76 to 2.88) and 1.89 times more likely to die following diagnosis compared with nonsmokers (95% CI, 1.29 to 1.76).

Those who smoked from 0 to 10 pack-years and 10 to 30 pack-years also showed some increased likelihood of adverse COVID outcomes. Using the same multivariable logistic regression model, which adjusted for age, race, and gender, the researchers found that the odds ratio for hospitalization was 0.99 and 1.41, respectively, and that odds ratio for death was 1.66 and 1.47, respectively.

"We have demonstrated in this single central registry of patients who tested positive for COVID-19 that increased cumulative smoking was associated with a higher risk of hospitalization and mortality from COVID-19 in a dose-dependent manner," the researchers write, adding, "The association between cumulative smoking and adverse COVID-19 outcomes is likely mediated in part by comorbidities."
Jan 25 JAMA Intern Med study