Vaccines and drugs get much of the attention in the scientific race to fight COVID-19. But companies have been working just as hard on ways to meet the enormous demand for testing. Those investments are beginning to pay off.

Abbott Laboratories Inc. and ThermoFisher Scientific Inc., two major players in coronavirus testing, reported third-quarter results Wednesday that beat Wall Street estimates thanks largely to this focus. They followed Roche Holding AG, another leader in testing whose earnings last week showed a similar windfall. All three companies reported impressive growth as they ramped up machine production and rolled out new types of tests.

Abbott’s $881 million in COVID-19 testing revenue accounted for nearly 10% of its total sales in the third quarter. ThermoFisher, which makes money by building testing machines and providing other services and supplies to labs, generated $2 billion in COVID-19 related revenue, up from $1.3 billion last quarter. Revenue at Roche's molecular diagnostics business, which includes much of its coronavirus testing operations, more than doubled in the third quarter compared with the same period last year.