COVID-19 Testing: What Parents Need to Know
From nasal swabs to blood draws, here’s what all those tests mean
By Katie Sweeney
Who should be tested for the novel coronavirus that causes COVID-19? And what do the different types of tests actually measure? Attending Physician Jeffrey Bender, MD, a pediatric infectious disease specialist at Children’s Hospital Los Angeles, gives the latest update and explains what parents need to know.
Who should be tested?
Children’s Hospital Los Angeles now routinely tests for COVID-19. All children admitted to the hospital or who are undergoing a procedure are tested. Children with symptoms, patients who are medically fragile, or children who live at home with medically at-risk individuals are also tested if it is determined medically important by the treating provider.
One of the reasons why the test is given is because it “helps protect our staff, patients, and their families, and ensures that the right personal protective equipment is used when providing care,” Dr. Bender explains.
Types of COVID-19 tests
- RT-PCR assays:
This is the test preferred by the Centers for Disease Control and Prevention (CDC) to determine if an individual has the virus. The test uses a swab at the end of a long, thin stick to collect material from deep in the nasal passage—where the nose connects to the throat. The lab looks at the sample for genetic material that matches the virus. There are many platforms now available to detect SARS-CoV-2 (COVID-19).
- Rapid antigen tests:
This test works like a rapid test for influenza. The swab collects a sample from the front of the nasal passage or throat, which is checked for viral proteins and gives results in minutes.
Dr. Bender is cautious. “A problem with rapid flu tests is that they can be hard to interpret,” he notes. “A rapid COVID-19 test has the same issue. At Children’s Hospital, we have no plans to use rapid antigen tests.”
- Antibody test:
This tests the blood to see if the person has had the virus in the past. (It cannot tell if a patient has the virus right now.) These tests check for antibodies against the virus—special proteins that the body makes to fight an infection. “These tests are especially helpful for testing health care workers and in supporting public health efforts,” Dr. Bender explains.
Tests at our Hospital
The Laboratory at Children’s Hospital Los Angeles is using a number of RT-PCR assays that the Food and Drug Administration (FDA) have authorized for emergency use (EUA). One of the primary tests that is used is the CDC-EUA PCR assay. “Many labs still don’t have the technology to run these tests,” Dr. Bender says. “Our lab is very advanced, and we were one of the first to bring this testing online. This is a testament to the amazing work of our clinical lab.” Results are typically ready in less than 24 hours.
The CHLA lab has also implemented a COVID-19 antibody test that can check for past infection. It is currently available for ordering by physicians who deem it medically important to determine past infection.
Should my child be tested?
In the vast majority of cases, children still don’t need to be tested. Children with COVID-19 typically only have mild cold symptoms, instead of the more serious illness seen in adults. One benefit of testing is to inform the child and parent of the infection, which may help prevent further transmission. The need for testing is a discussion you should have with your pediatrician.
Regardless of testing, if your child gets a cold, adults in the home should take extra care to not catch the cold—and frequently wash their hands and disinfect surfaces.
If a child has more severe symptoms—persistent high fever, trouble breathing and not eating or drinking well—call your pediatrician. “I would encourage parents to reach out to their pediatrician first,” he says. “But if it’s severe and the child is getting worse, then you need to go to an emergency department.”
Parents and caregivers should listen to local health officials about social distancing and stay-at-home orders. And they should continue to wash their hands often—and teach their children how to wash their hands and cover their cough.
“These simple measures will help kids not only now, but also in future flu seasons,” Dr. Bender says. “They are learning life lessons that will protect them throughout their lives.”