The coronavirus primarily spreads from person to person and not easily from a contaminated surface. That's the takeaway from the Centers for Disease Control and Prevention, which this month updated its "How COVID-19 Spreads" website.
The revised guidance now states, "The virus spreads easily between people." It also notes that the coronavirus, which causes the disease covid-19, "is spreading very easily and sustainably between people."
The CDC also clarified what sources are not major risks. Under a new heading, "The virus does not spread easily in other ways" the agency explains that touching contaminated objects or surfaces does not appear to be a significant mode of transmission. The same is true for exposure to infected animals.
CDC spokeswoman Kristen Nordlund said Thursday that the revisions were the product of an internal review and "usability testing."
"Our transmission language has not changed," Nordlund said. "Covid-19 spreads mainly through close contact from person to person."
The virus travels through the droplets a person produces when talking or coughing, the CDC website says. An individual does not need to feel sick or show symptoms to spread the submicroscopic virus. Close contact means within about 6 feet, the distance at which a sneeze propels heavy droplets.
Example after example have shown the microbe's affinity for density. The virus has spread easily in nursing homes, prisons, cruise ships and meatpacking plants -- places where many people are living or working in close proximity. A recent CDC report described how a choir practice in Washington state in March became a super-spreader event when one sick person infected 52 others.
"Direct contact with people has the highest likelihood of getting infected -- being close to an infected person, rather than accepting a newspaper or a FedEx guy dropping off a box," said virologist Vincent Munster, a researcher at the Virus Ecology Section of Rocky Mountain Laboratories, the National Institute of Allergy and Infectious Diseases facility in Hamilton, Mont.
Munster and his colleagues showed in laboratory experiments that the virus remained potentially viable on cardboard for up to 24 hours and on plastic and metal surfaces for up to three days. But the virus typically degrades within hours when outside a host.
The change to the CDC website, without formal announcement or explanation, concerns Angela Rasmussen, a virologist at the Columbia University School of Public Health.
"A persistent problem in this pandemic has been lack of clear messaging from governmental leadership, and this is another unfortunate example of that trend," she said. "It could even have a detrimental effect on hand hygiene and encourage complacency about physical distancing or other measures."
The website, archived on May 1, includes the same statement about surfaces as the current version: "It may be possible that a person can get COVID-19 by touching a surface or object that has the virus on it and then touching their own mouth, nose, or possibly their eyes. This is not thought to be the main way the virus spreads, but we are still learning more about this virus."
A Section on 05/22/2020