Antibody testing is here.
Christus St. Vincent Regional Medical Center in Santa Fe is now offering a test that can determine whether a person has been exposed to the novel coronavirus.
“Once you have it, it says that you have been exposed and you’ve had a normal immune response to it and you have some kind of protection,” Lance Wilson, president of Christus St. Vincent’s clinician group, told The New Mexican.
In recent weeks, policymakers and health officials around the nation and world have said they hope testing for antibodies — a protein found in blood that attacks bacteria and viruses — could give them a more accurate understanding of how much of the population has been infected with COVID-19 and could help guide decisions on when to reopen the economy.
New Mexico plans to implement these blood tests, too. Gov. Michelle Lujan Grisham said last week that the state was preparing to implement the tests and already had a strategy for identifying and purchasing materials approved by the Food and Drug Administration.
“Until you know exactly who’s been exposed and exactly how many people have antibodies and exactly how many people have the virus and what age groups, you don’t have enough information to make the next set of decisions,” Lujan Grisham said Wednesday.
Antibody studies carried out in some parts of the U.S. have shown many more people likely have been exposed to the virus than previously believed. Preliminary results of a study released last week showed 1 of every 5 New York City residents tested positive for antibodies, the New York Times reported.
Yet state officials have cautioned, as did Christus St. Vincent, that antibody tests aren’t yet able to determine with certainty whether a positive result means a person is immune to the disease.
Indeed, the World Health Organization said Friday there is currently no evidence people who have recovered from the disease and have COVID-19 antibodies are safe from developing a second infection. It warned policymakers against using antibody test results to issue “immunity passports” or “risk-free certificates” to people who test positive.
“Yes, you’ve probably been exposed and you’re developing antibodies,” Wilson said of a person who tests positive. “But we don’t know at what level of antibody production that means you’re immune and you’re protected and you’re safe to go back to work or you’re safe to be in the community.”
The New Mexico Human Services Department reiterated Monday that “the level of antibodies needed to make someone immune from COVID-19 or how long the protection might last is still unknown,” spokeswoman Jodi McGinnis Porter said.
Still, performing the tests can help providers like Christus St. Vincent collect data to develop a more precise understanding over time of what level of antibodies might guarantee immunity, Wilson said.
Christus St. Vincent is offering two types of antibody testing. One, called an “IgG” test, can be requested by any patient who has a doctor’s order. Patients get their blood drawn at Christus St. Vincent’s Entrada Contenta facility, and the samples are then processed by the Mayo Clinic, which is partnering with the hospital.
The other test is performed internally by the hospital before health care workers carry out certain procedures to help make sure patients are low-risk, Wilson said.
“Not a lot of the hospitals in New Mexico have access or are using this test,” Wilson said of the inpatient antibody testing. “But we’re not using it by itself. We’re using it just as an additional piece of information for screening for people that are low-risk already.”
The state has provided a list of circumstances under which its Medical Advisory Team recommends antibody testing.
The Human Services Department said Monday the state was still waiting for additional details on a federal pilot program in which it is participating that may include antibody testing.
The Department of Health is negotiating with Abbott Laboratories to buy “serologic test reagents when they become available,” McGinnis Porter said.
Christus St. Vincent’s antibody tests also will help the provider determine which patients can donate plasma that can be given to another patient who has contracted COVID-19.
Christus St. Vincent last week carried out its first plasma transfusion for the disease in cooperation with a national program led by the Mayo Clinic. Since then, the hospital has performed its second such procedure.
One of those two patients has since improved enough to be discharged, while the other is still on a ventilator but is showing signs of improvement, Chief Medical Officer David Gonzales said.
Gonzales said it was too soon to say for sure whether the improvement in the patients’ conditions was due to the plasma transfusion but that it was a “promising observation.”
The hospital is part of a nationwide study to determine the efficacy of the procedure, and it is looking for people who have had COVID-19 to donate blood so it can have more samples for the study, Gonzales said.
People can donate 14 to 28 days after they first tested positive for the disease, and those interested in donating can call 505-913-4256.
Christus St. Vincent also has expanded its capacity for testing performed with a nasal swab to determine whether a person has COVID-19.
Unlike many providers in New Mexico, the hospital has a laboratory on-site where it runs some of the samples it collects, Wilson said. That allows the hospital to produce results in less than an hour, he said.
Christus St. Vincent sends the bulk of its samples to the Mayo Clinic for processing.
The hospital has done 1,365 tests, of which 1,299 have been negative and 20 are still in process. Eight patients have been hospitalized for the disease at Christus St. Vincent since the outbreak began, with three currently admitted at its COVID-19 unit.
A total of 58,803 COVID-19 tests had been performed in New Mexico as of Monday afternoon, with 2,823 people testing positive and 104 deaths related to the disease.
Christus St. Vincent also has been processing samples collected by other community health care providers, the Indian Health Service and corrections facilities such as the Santa Fe County jail.