When most of us think of "coronavirus stocks," we think of the pharmaceutical or biotech companies working on treatments or vaccines. But there's another kind of coronavirus stock out there -- one whose products are already generating revenue. 

I'm talking about Abbott Laboratories (ABT 2.60%), which recently launched three tests for COVID-19, the illness caused by the novel coronavirus. Now the company is working on a fourth.

A nurse holds up a blood sample for coronavirus testing.

Image source: Getty Images.

Each test suits a particular need as the healthcare community and governments attempt to wage war against the virus, which has resulted in more than 2.5 million cases worldwide. The first is a molecular coronavirus detection test to be run on Abbott's m2000 RealTime system in hospitals and laboratories. The second is another molecular test, but this one is the world's fastest, and it's portable, so it may be used in point-of-care situations. This test, run on Abbott's ID NOW platform, produces positive results in as little as five minutes and negative results in 13 minutes.

Antibody blood test

The third test is a bit different. This one is a laboratory-based antibody blood test that detects whether a person has had COVID-19. Tests like this may offer insight into how long antibodies remain in the body and whether they offer immunity for the future. Abbott's test detects the IgG antibody, a protein developed late in the illness that may be left behind for months or years. As governments try to open countries back up for business, such a test could be crucial because it has the potential to show how much of the population may have immunity.

Abbott's fourth test, now in development, might offer another key element in the fight against COVID-19. It is a lateral flow serology test that would make mass testing across the entire population possible. Lateral flow serology tests detect a target substance in a liquid sample without the need for other equipment, meaning it's an ideal way to approach large-scale testing.

Abbott brought the first three tests to market in March and April, too late for a meaningful contribution to first-quarter earnings, but investors should keep an eye on the performance of the company's diagnostics business in the second quarter. A boost from the coronavirus tests will be welcome, as the coronavirus outbreak resulted in fewer routine laboratory tests during the first quarter. As a result, revenue in core laboratory diagnostics fell by 6.8%. Diagnostics as a whole only fell 0.8% as growth in molecular and other tests compensated for losses elsewhere.

The best stock yet?

So why is Abbott the best coronavirus stock yet? The global coronavirus diagnostics market is expected to reach $2.2 billion by 2025, according to a new report by TechSci Research. The lack of tests since the start of the coronavirus outbreak has been one of the main challenges worldwide, so a company that is able to provide the necessary number may be one of the winners in the race to contain the virus.

At this point, treatments and vaccines for the coronavirus are involved in clinical or pre-clinical testing. If you're investing in a product's developer because of its coronavirus work and the company's other programs, that's a great idea. If you're only betting on approval of the coronavirus product, that may be risky business.

Two advantages

Abbott offers two significant advantages over other companies working on treatment or vaccines: Three of Abbott's coronavirus products are already commercialized, and the company already has many successful products on the market in areas including diagnostics, medical devices, and nutrition. First-quarter global sales totaled $7.7 billion, a 2.5% increase in spite of disturbances due to the coronavirus outbreak. Like many of its peers, Abbott has suspended guidance for the year because it still is too early to say how long the outbreak will last. But thanks to its solid position, we can expect any negative impact would be temporary.

Abbott shares have increased 9% so far this year, a satisfactory performance considering the 13% decline by the S&P 500. Still, the stock's gains pale when compared to those seen at clinical-stage biotech companies including Moderna (MRNA -1.80%) and Inovio Pharmaceuticals (INO -1.43%), which have climbed by 142% and 262%, respectively, this year. But for a long-term investor who wants to bet on a company where coronavirus-related work is part of an already booming business, Abbott may be the best choice yet.