Maine’s phased reopening plan relies on detecting and isolating people infected with the coronavirus, but public health experts say the testing regime envisioned by the state is likely too small to accomplish that.
Gov. Janet Mills’ four-stage plan announced Tuesday cautiously opens parts of Maine’s economy step by step, with state officials ready halt the process or reimpose restrictions if they see indications the virus is spreading rather than retreating.
But the testing regime supporting it is far less extensive than many public health experts recommend, and it continues to focus on people entering or residing in health care facilities or in congregate settings that experience active outbreaks.
Dr. Nirav D. Shah, director of the Maine Center for Disease Control and Prevention Derek Davis/Staff Photographer
That testing strategy – outlined by Dr. Nirav Shah, director of the Maine Center for Disease Control and Prevention, in an interview with the Portland Press Herald/Maine Sunday Telegram – envisions increasing Maine’s testing capacity twofold to threefold over the coming weeks, from about 1,000 tests per day to 2,000 to 3,000. The increase – which he and other lab operators say is achievable, despite shortages of reagents, swabs and other critical testing elements – would allow greatly expanded testing within the health care system.
“We start working on testing patients who might be in the hospital before they go back to a nursing home and vice versa, every single patient that is scheduled for an elective surgery, every expectant mother close to delivery,” Shah explained. “The types of people I believe it would be necessary to test to get a handle on the outbreak.”
The state would also be able to expand its testing in congregate settings such as industrial plants, homeless shelters and long-term care facilities. Currently, everyone living or working in such a setting is tested if there are three or more confirmed cases, the technical definition of an outbreak. The expanded capacity would allow testing everyone once there has been a single case.
But Maine’s testing capacity – which works out to an ability to test 0.15 to 0.22 percent of the population each day – would not be sufficient to test asymptomatic people more widely, as is being done in Los Angeles County, where every citizen is being offered a free test.
Shah said this testing strategy parallels the recommendations laid out in a widely circulated April 18 article by Dr. Ashish Jha of the Harvard Global Health Institute and Dr. Thomas Tsai of the Harvard T.H. Chan School of Public Health. They calculated the minimum number of tests needed to detect most new infections, allowing officials to quickly isolate those people and those they came in contact with, rather than being forced to isolate everyone when the outbreak surges. The article, which was featured in The New York Times, calculated the nation needs 500,000 tests a day, or 1 per 152 people, meaning Maine would need about 8,800 daily.
In an interview, Tsai said this number represents “the bare minimum” requirement.
“I don’t think it may be enough,” Tsai, who is also a surgeon at Boston’s Brigham and Women’s Hospital, told the Press Herald/Sunday Telegram. “We need to be testing 5 million if we could or 20 million a day (nationally) if we could. Initially the U.S. was so constrained by the supply chain we could only test the very sick and front-line health care workers. But now that testing capacity is slowly improving.”
“Maine doesn’t have to wait for people to come to the hospital,” he added. “Because it’s a less densely populated state, it has an opportunity to build that surveillance infrastructure to be able to track individual cases and trace them out in a way that is not possible if you are in the middle of an outbreak.”
A more detailed interdisciplinary report organized by Harvard’s Edmond J. Safra Center for Ethics argues that a much wider testing net will be required if Maine and other states are to avoid having to shut down their economies over and over until a vaccine is available. To test broadly enough to detect asymptomatic carriers of the disease – estimated at 20 to 40 percent of the total infected – would require the ability to test 2 percent of the population a day during May, ramping up to 5 percent in August, when more restrictions are removed.
That translates to 27,000 and 67,500 tests a day in Maine – an order of magnitude more than the Maine CDC is contemplating – plus a small army of contact tracers who can figure out whom each positive case may have already infected. A system would need to be in place, the study argues, to support each infected person while they isolate.
“We think getting to enough testing to ward off a second wave should be the goal, and that does require even more of an increase than Maine proposes here,” the Safra Center’s director, Danielle Allen, said of Maine’s plan via email.
Dr. Edison Liu, president and CEO of The Jackson Laboratory, which developed COVID-19 testing capacity in March, said widespread testing of asymptomatic people is essential.
“We need to be able to know, in the workplace, who is infectious and who isn’t,” said Liu, who led Singapore’s scientific response to the 2003 SARS pandemic. “Just as you would stop somebody carrying a loaded gun into your workplace, you should be able to prevent a person shedding the virus from coming into the workplace because they are a danger to their co-workers.”
“Health care workers, individuals in grocery stores, nursing home caretakers, first responders – these people need to be tested now,” he added. “Test the call centers, the paper plants and every person who is incarcerated.”
TRIPLING THE CAPACITY
The good news is that, despite shortages of swabs and reagents, Maine laboratory managers believe they can achieve the doubling or tripling of the state’s testing capacity envisioned by the Mills administration’s plan.
Shah said the Maine CDC’s own lab has a capacity of 300 tests a day and, with the expected arrival of two testing instruments in the coming days and weeks, intends to reach 500 daily tests. He said the agency is hiring two additional lab staff members.
The biggest challenge to achieving these goals remains the shortage of reagents – chemicals required to conduct the tests – but the new instruments will help alleviate the problem, because they require a reagent pack that is less difficult to secure.
NorDx, based in Scarborough, can handle about 250 COVID-19 tests a day, most of which come from health care providers who share its membership in MaineHealth, the state’s largest hospital network. Laboratory medical director Robert Carlson said NorDx is seeking to double that capacity to 500 in the next few weeks as the national shortage of reagents abates.
“At this point, it’s mostly a reagent constriction, but once we hit 500 or 700 tests a day, we will have reached the capacity of our current instrumentation as well,” Carlson said.
If Maine does seek to increase testing more widely, it’s not clear how difficult that would be.
An unknown amount of additional testing capacity is already drawn from out-of-state labs like New Jersey-based Quest Diagnostics and North Carolina’s LabCorp, though these options often have long turnaround times, limiting their usefulness.
‘TELL US WHAT YOU NEED’
Jackson Lab is already processing 700 tests a day at a testing site it set up in March at its campus in Farmington, Connecticut, Liu said, and it is expanding to be able to process 20,000 a day in the next six to eight weeks, 20 times Maine’s current capacity.
“I have no doubt I can get to 20,000. It’s an issue of time and money,” said Liu, who has partnered with Connecticut’s public health department and two hospital systems, UConn Health and Hartford HealthCare, on the project. Reagents haven’t been an issue for Jackson, he said, because of a relationship with the manufacturer of their instruments, ThermoFisher.
Most of Jackson’s expanded capacity will serve Connecticut, but Liu said the Bar Harbor-based institution could create large-scale capacity for Maine as well, if state officials committed to it.
“For a state of 1.3 million people, we can get the number of tests that would be necessary very, very soon,” he said. “It’s not a whole ton of people; it just depends on how you roll it out. It’s an issue of will and an issue of organization.”
“Don’t ask us what we can do,” Liu added. “Tell us what you need, and we will get it done.”
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