There is no agreed-upon definition that specifies exactly which symptoms trigger the need for a test. One expert says that if a meeting includes, for example, someone with stage 4 cancer, it would be appropriate for all attendees to pre-test.
Technically, anyone who wants a COVID-19 test can walk into a pharmacy or health care office and get one. In reality, however, access to the tests has been uneven and questions remain about the accuracy of the various tests. “We know that molecular testing has the highest sensitivity to rule out COVID — to rule out,” said Nira Pollock, MD, PhD, a member of the Infectious Diseases Society of America (IDSA), which tracks the state of COVID — 19 tests. Pollock, the associate medical director of the Infectious Diseases Diagnostic Laboratory at Boston Children’s Hospital, points out that questions also remain about “turnaround time, costs, and supplies for both patients and labs.”
Even as testing has evolved, long lines at healthcare facilities can persist, Pollock says. It can be difficult to get an appointment at a pharmacy, and fewer state test sites remain open. Supply chain issues mean that testing supplies are not always plentiful. Samples can be shipped to labs with long lead times. And while the tests themselves are free to consumers, office visits may involve copays.
Home testing offers many more conveniences with a potential pitfall: the possibility of a less accurate result. “Most of the available home tests are…antigen rapid diagnostic tests, or RDTs,
and they have significant potential benefits,” says Pollock. These include fast turnaround and lower costs, at least for third-party providers. Because home tests are relatively inexpensive and fast, they can be used for serial testing, although there is no consensus on the optimal interval between tests. However, the ability of rapid tests to detect the virus is somewhat reduced compared to that of PCR tests. “There is still disagreement about whether a negative RDT can effectively rule out infection in a symptomatic individual,” Pollock notes, adding that a person can have a negative antigen test and positive PCR test and be contagious.
One problem with home tests is that people can administer them incorrectly, which can affect the results. Another problem is that positive results may not be reported. “I think we’re probably going to lose track,” says Dial Hewlett Jr., MD, FIDSA, an IDSA fellow and medical director of the disease control division at the Westchester County Department of Health in New York. “We won’t have such an accurate idea of what the prevalence of the disease is at any given time. On the other hand, I think it will be helpful to access these results in a very quick way in terms of the practicalities of going to school.”
Rapid testing can indeed be the key to keeping kids in school, although there are obstacles.
There is no agreed-upon definition that specifies exactly which symptoms trigger the need for a test. There is also no consensus on the need for school testing if transmission rates are slow in an area. Pollock cites the Test and Stay program being tested in select counties by the Centers for Disease and Control and Prevention (CDC), which includes regular on-site rapid tests and contract tracking of potentially exposed children and staff so they don’t have to quarantine at home to go .
Although PCR tests produce more positive results than rapid tests, the delay time between testing and results can be up to several days. This can be problematic if people don’t go into quarantine while waiting for results. Hewlett explains that under the vaccine mandate for health professionals, those in his county who receive waivers must undergo molecular testing once a week. “The shortcoming of this is that a person can test negative on Monday and then actually develop symptoms on Tuesday,” he says. Meanwhile, colleagues during that time may be exposed.
For vaccinated but asymptomatic individuals, when and whether to test is a more nuanced discussion. If a group is planning to get together for the holidays and they are all vaccinated, should they all undergo COVID-19 testing beforehand? The answer depends on whether a person is frail due to age or comorbidity, the experts agree. “[T]esting in vaccinated people is really a risk balance — risk to the people around you, risk to yourself and your health history, and also access and resources,” Pollock says. Hewlett says that if the meeting includes, for example, someone with stage 4 cancer, it it would be appropriate for all attendees to test before meeting.
The panel’s experts complained that finances can play a role in a person’s decision to get a COVID-19 test. While tests performed in an urgent care center or lab are free to consumers, reports of third-party bills being sent to insurance companies or the government are not unheard of. And quick home tests can start at $25 for a 2-pack and go up to $35 or more, which is out of reach for many families, especially those with multiple children. “The fact that someone with resources can get a test to rule out COVID in their child and get that child back to school faster than possibly someone without those resources — it just shouldn’t be,” Pollock says.
Pollock adds that it has been difficult to find rapid tests lately, although the Biden administration has invested heavily in their development and availability, which should make them easier to obtain for the winter season.
This article first appeared in Infection®.