By John Miller

ZURICH (Reuters) – Only high-risk patients and those showing signs and symptoms of the new coronavirus should be tested because capacity remains too limited for now to screen everybody, Roche Chief Executive Severin Schwan said on Thursday.

Roche, ThermoFisher Scientific, Hologic and Laboratory Corporation of America have gotten emergency U.S. Food and Drug Administration authorisation for their tests. Schwan said that is helping to increase capacity as confirmed cases worldwide now exceed 200,000 and deaths top 8,000.

Schwan said limited hospital testing infrastructure and the availability of personnel to perform the screens have led to bottlenecks. He said neither commercial considerations nor regulatory approvals, which he said Roche got from the FDA within 24 hours after submitting it, are holding things back.

“There is simply not enough capacity, and as we are all aware, the incidence rates are rapidly increasing,” Schwan told reporters on a call with other drug industry executives, organised by the International Federation of Pharmaceutical Manufacturers and Associations (IFPMA).

So far, some drugs traditionally used against the HIV virus have flopped against the coronavirus. Rajeev Venkayya, the president of Takeda’s vaccines unit, said from Boston that he anticipates a medicine for the most critically ill patients to likely take up to 18 months – about as long as companies also predict it will take to come up with a vaccine.

Containing this disease has been particularly challenging because so many people who have contracted the virus show few or no symptoms but remain contagious for others, executives said.

“You can not be showing clinical symptoms, you may not even know you have it, but there is the possibility you can transmit it to other people,” Venkayya said. “That is why this virus has been transmitted around the world with such speed and stealth. It has been operating under the radar.”

Being able to perform more tests will help doctors and scientists better understand community-level transmission so that draconian containment strategies like the worldwide restrictions on travel and free movement that have sent the economy into a tailspin can be replaced with less-disruptive alternatives, Venkayya said.

(Reporting by John Miller; editing by Stephanie Nebehay)