June 1, 2020

NIOSH Director: COVID-19 Vaccine Development Moving Quickly, but Hurdles Remain

By Ed Rutkowski

NIOSH Director Dr. John Howard summarized the current state of knowledge regarding the COVID-19 pandemic at AIHce EXP 2020 this morning, addressing disease transmission, testing, mitigation strategies, and vaccine development. The session was held live over the internet as part of the first-ever fully virtual AIHce.

Howard’s message regarding a vaccine was hopeful but cautionary. “Things are happening faster than we’ve ever seen before,” Howard said of efforts around the world to develop a vaccine. But given that development encompasses several phases with the last involving thousands of volunteers, it is likely to take 12 to 18 months before a vaccine is ready. Howard also reminded listeners that resistance to vaccination has taken hold among people who question the safety of vaccines. “It’s important to remember even when we do get a vaccine” that convincing people to take it will be a challenge, Howard said.

Howard emphasized the role of aerosols in transmitting COVID-19, explaining that infected individuals generate particles containing the virus when they cough, sneeze, or speak. While the larger droplets fall to the ground relatively quickly, smaller particles can stay airborne for long periods. Recently published research indicates that even speech from asymptomatic people can transmit disease, Howard said.

Pre-symptomatic and asymptomatic people have been shown to play a significant role in transmitting COVID-19. Reports from CDC in March and April indicated that approximately half of the residents of a Seattle nursing home who tested positive for COVID-19 had no symptoms at the time of testing. On the Diamond Princess cruise ship, which was the focus of another CDC report, 47 percent of infected passengers were asymptomatic at the time of testing.

The virus can also be transmitted through contact with surfaces that have infectious material, Howard said. The length of time the virus lasts on certain surfaces varies.

Serology testing, which detects the presence of antibodies, looks for evidence of prior infection but does not identify whether people are protected from re-infection. Howard said that experiments have shown that antibodies protect monkeys from reinfection, but scientists do not yet know how long this protection lasts.

Mitigation strategies developed by CDC in recent weeks have attempted to address the many ways that people congregate at home, at work, and during transport. While guidelines vary for different circumstances, the primary strategy, Howard said, is to keep infected people away from the non-infected. Studies are showing that stay-at-home orders have been very effective in reducing transmission.

A number of products, many containing ethanol or sodium hypochlorite, are effective at disinfecting surfaces, Howard said. EPA has published a list of products for use against SARS-CoV-2, the virus that causes COVID-19.

While no medications have been approved for treatment of COVID-19, the antiviral Remdesivir has shown promise. A recent study in the New England Journal of Medicine indicated that the drug shortened the time to recovery for individuals with the disease.

Ed Rutkowski is editor-in-chief of The Synergist.