A new Centers for Disease Control and Prevention (CDC) report suggests that one coronavirus test may not be enough to be sure that someone has not been infected after exposure.
The report, published Monday, found that more than 70 percent of inmates at a Louisiana prison who were exposed to someone infected with coronavirus ultimately came down with COVID-19.
But about 25 percent of them tested negative once, or even twice, between exposure and getting a positive result.
As the threat of asymptomatic spread becomes clearer and outbreaks rage in detention facilities the US, the CDC underscores the need to perform ‘serial’ diagnostic tests, especially on those who have been exposed to someone with coronavirus and those living in densely-packed group settings.
It also comes as California’s San Quentin Prison revealed more than 1,000 of its inmates have been infected.
Coronavirus has spread like wildfire in US prisons, including one in Louisiana where 72% of inmates in dorms where someone was infected caught the virus, despite stepped-up disinfecting measures and quarantines (file)
US prisons, where overcrowding is a common problem, have become hotbeds for the spread of coronavirus.
SARS-CoV-2, the virus that causes COVID-19, is a highly contagious pathogen, far more so than its cousins in the coronavirus family, SARS and MERS.
It loves nothing more than crowds in confined spaces, making prisons perfect fodder for coronavirus’s spread.
On March 29, a staff member at one Louisiana prison (which the CDC does not name) developed coronavirus symptoms.
Shortly thereafter, the person tested positive for COVID-19.
Within a matter of days, two more employees of the facility and a first prisoner tested positive.
In the entire prison’s complex, there were 700 prisoners, spread out across 15 dormitories.
For the next month, the prison staff did daily temperature and blood-oxygen level screenings of the inmates, which led to the diagnoses of 35 inmates, spread across five dormitories between April 8 and May 7.
The 98 inmates were tested for coronavirus daily, and 16 tested negative once and two tested negative twice before they were finally diagnosed with COVID-19 (file)
Everyone who tested positive was transferred for treatment, and the 98 remaining prisoners in those dormitories were placed under quarantine.
Then, the Louisiana Department of Health and the CDC swept in to begin a full-scale screening operation on May 7.
Already, on day one, 53 people tested positive.
The health officials continued to test the prisoners for two weeks. By the end of that period, 71 people tested positive, meaning that the virus spread to 72 percent of people sharing a building with the original 35 infected prisoners.
Sixteen of those people tested negative once before eventually testing positive and two tested negative twice before their cases were confirmed.
Nearly half of the prisoners (45 percent) said they had no symptoms when they were tested.
‘The high attack rate within these five dormitories and the large proportion of asymptomatic persons with SARS-CoV-2 infection suggest that serial testing of close contacts, including those in congregate settings, should begin immediately after identification of a case to limit further transmission,’ the CDC report authors wrote.
‘Some persons infected with SARS-CoV-2 were likely not detected until weeks after they had been infected, which could have contributed to rapid transmission within the quarantined dormitories.’
According to Politico, at least 1,327 inmates in federal prisons were covid-positive as of June 20. Another nearly 5,000 had been infected and recovered and 98 had died.
The CDC report makes clear just how easily coronavirus can spread in the confined quarters of prisons – even if swift action is taken to isolate infected people.
But it has implications beyond prison walls, too.
‘High rates of COVID-19 transmission in correctional and detention facilities also have the potential to influence broader community transmission,’ the CDC report says.
‘Reducing transmission in correctional and detention facilities potentially also reduces transmission in communities where staff members live and where detained persons return when released.’