The Centers for Disease Control and Prevention (CDC) has revised coronavirus testing guidelines particularly for asymptomatic individuals.
CDC no longer recommends testing for people who have been exposed to the virus, saying that individuals who do not manifest symptoms “do not necessarily need a test.”
The agency advised people who are vulnerable to the coronavirus to take the test if they have been within 6 feet of an individual who is Covid-19 positive for at least 15 minutes.
CDC previously suggested testing for individuals with a “recent known or suspected exposure” to the virus even if they did not show any symptoms. According to the CDC’s previous guidance, “the potential for asymptomatic and pre-symptomatic transmission” is cited as a reason why asymptomatic people who were exposed to the virus must be “quickly identified and tested.”
Several studies revealed that people who do not show symptoms can still carry and spread the virus. This can happen even in the presymptomatic phase a few days before symptoms manifest or if they are asymptomatic and do not experience symptoms.
Negative tests
“You do not necessarily need a test unless you are a vulnerable individual or your health care provider or State or local public health officials recommend you take one,” the CDC’s site says of asymptomatic people who had been exposed to an infected person for at least 15 minutes. “A negative test does not mean you will not develop an infection from the close contact or contract an infection at a later time.”
The agency added new language pertaining to asymptomatic individuals as “healthy people,” which is similar to language that is typically used on social media posts that oppose to the use of masks.
“In areas where there are limited number of new cases, State or local public health officials may request to test a small number of asymptomatic ‘healthy people,’ particularly from vulnerable populations,” the new guidance shows.
The CDC’s updated guidance mentions that people can carry and spread the virus, even if they do not manifest any symptoms and feel healthy. According to the agency, its “current best estimate” is that up to 50% of spread of the virus happens before people start to experience symptoms.
Assistant Secretary for Health Adm. Brett Giroir, who heads the Trump administration’s testing effort, defended the change in coronavirus testing guidelines. He said that it aims to empower local health officials and clinicians. He also dismissed allegations of succumbing to political pressure from the Trump administration.
“Let me tell you, right up front that the new guidelines are a CDC action,” he said, stressing that members of the White House coronavirus task force, such as Dr. Anthony Fauci and CDC Director Dr. Robert Redfield, are knowledgeable of the new guidelines.
"Frustrating"
Dr. Michael Mina, a professor of epidemiology at Harvard’s School of Public Health, emphasized the importance of testing people who do not show any symptoms for Covid-19 to help manage a targeted US response.
“It’s absolutely crucial that we continue to know who is spreading virus and that is largely due to asymptomatic individuals or at least there is a large fraction of spread that is asymptomatic,” he said. “That makes the new guidance frustrating, to say the least.”
Epidemiologists and former health officials also slammed the change in coronavirus testing guidelines because of the role that people without symptoms are suspected of playing in spreading the coronavirus.
“This makes no sense. People without symptoms account for up to 50% of transmission,” tweeted Dr. Leana Wen, a public health professor at George Washington University and former health commissioner of Baltimore. “We need MORE testing, not less.”
According to Dr. Tom Frieden, the former director of the CDC under President Barack Obama, the change in the guidance is “probably indefensible” and was “likely imposed on CDC’s website.”
Will Humble, executive director of the Arizona Public Health Association and former director of the Arizona Department of Health Services, described the change as “bizarre.”
“Testing contacts is a core part of contact tracing!” he said on Twitter. 50% of transmission happens before symptoms occur & you make this policy decision? The CDC brand is toast.”
