SIOUX FALLS, S.D. (KELO) — According to the South Dakota Department of Health, nearly 12,000 at-home COVID-19 test kits have been ordered directly through the DOH website in the last year.

The DOH at-home tests are free to order, and come with return shipping envelopes as well. The whole process is free of cost to South Dakotans.

Here you can watch a video walking you through the ordering process for the Vault Health PCR test through the DOH.

The tests themselves are provided by Vault Health, a virtual health care company that has been working with the state of South Dakota to provide lab testing for over a year now.

This lack of cost is what sets the DOH/Vault tests apart from many others available to consumers.

“The Vault Health [test] is an option that is free and available to all South Dakotans so that they don’t have to pay for a test,” said South Dakota state epidemiologist Dr. Josh Clayton. “If you are going to another location such as a pharmacy to purchase your test, there will be a cost associated with that.”

The other main difference between the Vault tests and other at-home tests that consumers can buy is the type of test itself. “With the Vault Health [test] it is a PCR test,” said Clayton. “Most of the at-homes [available in stores] are antigen-based tests.”

While PCR and antigen tests are different, Clayton stressed the fact that whichever you take, you should still trust the reliability of the result and take appropriate action if the test is positive.

But what is the difference between a PCR and an antigen test?

“It really is just a different way of testing for the sars-cov-2 virus that causes COVID-19,” Clayton explained. “The PCR is a method where you’re amplifying — what might be there for the genetic material of the virus itself, and you’re looking at that virus and saying yes it’s present or no it’s not present.”

This is different form how the antigen tests function. “Typically with the antigen tests, you’re looking at that spike protein on the surface of the virus itself, and that’s what the test binds to and then determines whether that’s positive or negative.”

Vault Health’s chief clinical officer Alexander Pastuszak explained this difference in greater detail while explaining why PCR tests are the “best in class” when it comes to COVID-19 testing.

“A PCR test tends to be among the most sensitive and specific and tends to essentially be quote unquote the gold standard for nucleic acid assessment because the test itself — the analysis process and the technology that’s used to detect the presence of nucleic acid — is exquisitely sensitive,” said Pastuszak.

An antigen test is just in and of itself less sensitive than a PCR test, just because the two things that are interacting — the thing you’re looking for and then the thing that gives you the signal — they don’t interact as tightly as the things that interact in the PCR-based test.

Alexander Pastuszak, Vault Health

Perhaps the most noticeable difference between a Vault test and an antigen test you could pick up at the store is that rather than receiving results within minutes at home, the Vault test must be sent to a lab for completion.

Vault currently runs two labs in the united states in partnership with Infinity Biologix, one in New Jersey, and one in Minnesota. This is where the tests go once mailed back.

Jacob Newton: “Tell me a bit about the process then with the tests. When I take mine; I drop it in the mail, it shows up at your lab in Minnesota; what happens then?”

Pastuszek: “So, testing in a lab is a standard, highly automated process. The samples are basically dropped off by the courier or logistics shipper at the lab — the trained lab personnel then take the samples; they essentially run them through what’s called an accessioning process which tells the lab that the sample is there, and then that sample is run through the nucleic acid extraction and analysis steps. Essentially, you take the sample, you get the viral RNA out of that, and then you put it into a form that’s ready to be analyzed by the systems in the lab.”

Pastuszek says that while the sample is being analyzed, there are specific probes looking for three distinct genes within the viral RNA. If at least two of the three genes are found to be present, then the test comes back positive. Once this is done, the test is returned to Vault, and the results are reported to patient and the state.

While PCR tests are more sensitive, antigen tests also have an advantage.

“What we know now is that the antigen tests better reflect when a person is considered infectious to others,” said Clayton. “If you test positive via a rapid antigen test, that’s very indicative of you being able to transmit the virus to others.”

This advantage comes down to the fact that the antigen test is less sensitive than the PCR test. Clayton explains that because the PCR tests are so sensitive, they are able to detect the virus whether it is alive or dead, meaning that you may test positive despite being past the point of being able to transmit the virus.

Despite this, Pastuszek notes that if a patient wants to be as sure as possible of their COVID-19 status, a PCR test is the way to go. That being said, he also acknowledges that there is a time and place for each version of the test.

“When do you use a test of a certain type,” he asked rhetorically. “[Antigen tests] are probably best used in the setting of somebody who has symptoms — there’s a much greater chance that a test like that is going to pick up and show a positive result in a person who is symptomatic than somebody who’s asymptomatic.”

If it were me — and I was symptomatic, I would take an antigen test, right? Just because I know that I can get it quickly, and in order for me to protect the people around me and answer the question of should I isolate and get away from people, I would want to take that. If there was a different situation where, for example I had been exposed and that I was concerned that maybe I was going to get it and pass it to people — then I would 100% always reach for a PCR test.

Alexander Pastuszak, Vault Health

Essentially, if you need confirmation of your COVID-19 status immediately, reach for a rapid antigen test; if you have time, but need to be certain, order a PCR test.

Time can absolutely be a factor between the two tests as well. When ordering a Vault test, you are told upon confirmation of the order that your test will be delivered to you the next day (unless you order after 3pm on a Friday, in which case your test kit will ship Monday). However the COVID-19 appears to be impacting this process just like any other.

I ordered my test at approximately 10:10am on Thursday, January 6, 2022. Despite this, my test did not ship until Monday, January 10, arriving the next day. Meanwhile, KELOLAND’s Rae Yost and Anna Peters also ordered tests on Monday, January 10, and also received them the next day.

Asked about this discrepancy in shipping times, five days as compared to just one, Vault Health’s director of communications Kate Brickman offered the following explanation via email:

Newton: “Are discrepancies in shipping times like this common?”

Brickman: “Typically, no. The majority of the time tests are delivered next-day with little to no issues. However, currently we are seeing some impacts to our day-to-day test operations caused by rising COVID-19 infection rates and surging demand. Like all industries – from airlines, to restaurants, to hospitals – our workforce is also being impacted by increasing COVID-19 infection rates. The unprecedented surge in demand for tests is straining all aspects of our testing system, including shipping, staffing, supply and more. We continue to work closely with our lab partner to deal with staffing shortages, deploying our national network of resources as efficiently as possible and hiring more people every day.”

Even if the process does unfold as planned, patients will still be looking at a minimum of three to four days from the time they request their test, to the time that they receive their results. In order to minimize potential delays, Clayton recommends planning ahead.

“Go ahead and order your kit now,” he said. “That decreases that delay in getting the kit to you, and then you can turn around and do that specimen collection and get that kit returned.”

You do not need to have been exposed to COVID-19 or be experiencing symptoms to request a Vault PCR test, meaning you can order one now in preparation of needing it in the future. In terms of shelf-life, Pastuszek says tests sent out now will last into 2023 before expiring. This longevity is another thing which sets the Vault test apart from a store bought antigen test, which often expires relatively quickly.

In terms of actually taking the test, the process involves following a link sent to your email to a virtual waiting room where you will await a Zoom meeting with a Vault technician who will oversee your test.

Check out this short video below for an explanation of the steps of the testing process.