Health-care companies rose as investors sought out sectors that were less sensitive to the spike in Covid-19 cases.

U.S. health officials warned that the coronavirus pandemic remained treacherous. The U.S. added more than 50,000 new cases for the first time Wednesday as case growth accelerated in populous states such as Florida and Texas.

The National Institutes for Health Director Francis Collins said the agency's goal will be to "have an additional one million tests per day available" by this fall through an experimental NIH program seeking to develop new kinds of Covid-19 diagnostic tests.

Separately, Federal health officials are in talks with the American Red Cross and blood organizations about ramping up the collection of blood plasma from recovered Covid-19 patients, in a large-scale effort to build supplies of the promising experimental treatment, The Wall Street Journal reported.

Drugmaker Alexion Pharmaceuticals agreed to pay more than $21 million to settle claims it bribed government officials to increase prescription drug sales in Turkey and Russia, the U.S. Securities and Exchange Commission said.


 Write to Rob Curran at rob.curran@dowjones.com