(Bloomberg) -- Quidel Corp., the U.S. diagnostics firm, is weighing a combination with Qiagen NV in another sign of ongoing appetite for dealmaking in the medical equipment industry, people with knowledge of the matter said.Quidel, which makes several types of coronavirus tests, has made a preliminary approach to Qiagen to gauge interest in a potential deal, the people said, asking not to be identified discussing confidential information.Deliberations are at an early stage, and there’s no certainty they will result in a deal, the people said.Qiagen’s U.S.-traded shares rose as much as 9.2% in New York Monday. The shares closed up 3.2% to $55.78, giving the company a market value of about $12.8 billion. Quidel rose as much as 7.5% before falling 1.7% to close at $232.88, giving the company a market value of $9.8 billion.“We continue to look at opportunities that would leverage our global infrastructure, or that contribute to our interest in digital and telehealth,” Quidel Chief Executive Officer Doug Bryant said in an emailed statement. “We’ve said that we will not enter into an agreement that isn’t an obvious strategic fit. Beyond that, we will not comment on rumors and will not comment further.”A representative for Qiagen declined to comment.Covid TestsCovid-19 testing has proved a lucrative market for diagnostics companies in the last year, especially amid a surge in U.S. infections in recent months. But investors are increasingly asking how long-lasting that demand will be, as vaccines being rolled out globally threaten to eventually dampen sales.Qiagen agreed last year to be acquired by Thermo Fisher Scientific Inc. for 43 euros per share, though the deal was scrapped in August after the bid failed to win shareholder support. The Dutch company has been the target of regular takeover speculation since that transaction fell apart, and other suitors could also emerge.San Diego-based Quidel in December received emergency clearance for its rapid Covid-19 test to be used in the U.S. The company expects to be able to produce 600 million of the QuickVue tests per year by the end of 2021.In all, Quidel has had six Covid-19 tests receive emergency-use authorization from the U.S. Food and Drug Administration, including gold-standard polymerase chain reaction tests, quick-turnaround antigen products and a combination flu and Covid-19 test, according to an agency database. Qiagen has had one, a panel that was authorized by the FDA to detect Covid-19 and a range of other viruses, including flu and RSV.Health-Care DealsHealth-care companies have announced $69 billion of deals this year, nearly quadruple the amount from the same period in 2020, according to data compiled by Bloomberg. Transactions have included AmerisourceBergen Corp.’s $6.5 billion acquisition of a majority stake in the wholesale business of Walgreens Boots Alliance Inc., as well as Jazz Pharmaceuticals Plc’s $7.2 billion purchase of cannabinoid-drug maker GW Pharmaceuticals Plc.(Updates with CEO’s comment in fifth paragraph)For more articles like this, please visit us at bloomberg.comSubscribe now to stay ahead with the most trusted business news source.©2021 Bloomberg L.P.