As COVID-19 case counts and deaths continue to rise and the stock market has struggled to regain its footing, one bright spot are the drugmakers and diagnostics companies moving forward with plans to develop tests, treatments, and vaccines for the novel coronavirus.

Pfizer, which has developed and marketed other vaccines, entered the COVID-19 vaccine race, saying Tuesday that it is working with BioNTech SE to help the German life sciences company develop and potentially distribute its COVID-19 vaccine candidate. In trading on Tuesday morning, Pfizer’s stock gained 4%, and shares of BioNTech soared 57%.

The first participant in Moderna Inc.’s MRNA, +2.91% closely watched Phase 1 trial for its COVID-19 vaccine candidate received a dose of mRNA-1273, the company said Monday. Moderna is running the trial in collaboration with the National Institutes of Health, with the goal of evaluating the safety of the vaccine in 45 participants, who are all healthy adults. Moderna’s stock is up 13%.

Regeneron Pharmaceuticals REGN, -1.72% said Monday it started enrolling patients in a Phase 2/3 trial in New York testing Kevzara, a rheumatoid arthritis drug it developed with Sanofi SNY, +0.71% , as a treatment for people who have been hospitalized with severe COVID-19 infections. Specifically, the companies want to know what impact Kevzara has on a patient’s fever and need for supplemental oxygen. The trial is expected to enroll up to 400 patients.

Regeneron is also planning to test antibodies in the prevention and treatment of COVID-19 in clinical trials later this summer. Shares of Regeneron gained 10%; Sanofi’s stock was up 0.2%.

In the U.S., there are now 5,702 people who have tested positive for COVID-19 and at least 94 have died, according to the most recent data from the Johns Hopkins Whiting School of Engineering’s Centers for Systems Science and Engineering.

Experts have said they expect the number of COVID-19 cases in the U.S. to be much higher; however, there have been both issues and delays with the test developed by the Centers for Disease Control and Prevention (CDC). The public health agency said 25,162 COVID-19 tests have been performed in the U.S., as of March 16. This includes 4,255 specimens tested by the CDC and 20,907 tests performed by public health laboratories using the CDC’s testing kit, between Jan. 18 and March 16. The CDC, which has not conducted a test since March 12, has been criticized by the low rates of testing, especially when compared with testing rates in other countries, like South Korea, which has tested more than 260,000 people, according to the Korea Centers for Disease Control and Prevention.

A number of commercial diagnostics makers including Hologic Inc. HOLX, +0.53% , Roche Holding AG ROG, +1.84% and Thermo Fisher Scientific Inc. TMO, -0.89% have recently said they received emergency use authorization from the Food and Administration for their COVID-19 tests. Roche said Monday it started shipping 400,000 test kits last Friday, and plans to ship an additional 400,000 tests to the U.S. immediately. Thermo said Monday it is ready to ship 1.5 million tests and that it has the capacity to send 5 million tests a week in April. Hologic Inc. plans to produce up to 600,000 tests in April for the U.S.

President Donald Trump on Monday called for Americans to radically curtail daily activities for 15 days, to slow the spread of the disease in the U.S. He told people not to gather in groups of 10 or more or to visit restaurants or bars. The Kaiser Permanente health system has postponed all elective and non-urgent surgeries and procedures. A set of new rules in San Francisco only allows people to leave their homes for doctor’s visits or food shopping unless they work in what the city calls an “essential business,” such as being a health care worker or garbage collector.

On Tuesday morning, some of the nation’s most prominent retailers and restaurant chains announced significant changes to their operations over the coming weeks, with fast-food giant McDonald’s Corp. MCD, -1.03% moving to a takeout or delivery model and discount retailer Dollar General Corp. DG, +2.26% asking people to allow senior citizens to shop during the first hour its stores are open.

Worldwide, there are now 194,217 cases of COVID-19 and at least 7,864 people have died. More than 80,000 people have recovered. In Western Europe, where the outbreaks appear to still be worsening, Italy has 31,506 cases and 2,503 deaths; Spain has 11,309 cases and 509 deaths; Germany has 8,604 cases and 23 deaths; and France has 6,664 cases and 148 deaths.

In South Korea, there are 8,320 cases and 81 deaths. And Iran, which is combating a severe outbreak of the novel coronavirus, has 16,169 cases and 988 deaths.

Here’s what companies are saying about COVID-19:

• Foot Locker Inc. FL, -0.44% has closed stores across North America, Europe, Middle East and Asia and Malaysia through March 31. The athletic retailer has also withdrawn its full-year outlook and plans to provide an update with its first-quarter earnings announcement on May 22.

• Michaels Companies Inc. MIK, -0.24% gave an outlook ahead of expectations but that didn’t take into account the impact of the coronavirus. Mark Cosby, Michaels CEO, said the company doesn’t expect “material supply chain disruptions” in the first quarter but sales in certain categories are slowing.

• L Brands Inc. LB, -0.52% closed all Victoria’s Secret, Pink and Bath & Body Works stores in the U.S. and Canada through March 29 due to the pandemic. It also withdrew its guidance for the first quarter.

• Lands’ End Inc. LE, +1.50% said the coronavirus outbreak has resulted in lower customer demand over the past week, and that it will not provide guidance for fiscal 2020 given the “rapidly changing business environment.”

• Canopy Growth Corp. CGC, -0.24% plans to close all of its corporate-owned retail stores temporarily over worries about the coronavirus. “This is a big decision but it was also an easy one to make — our retail teams are public-facing and have been serving an above-average volume of transactions in recent days,” CEO David Klein said in a statement. Cannabis companies have been reported a spike in demand for weed as more people are ordered to hunker down at home.

• Dunkin’ Brands Group Inc. DNKN, -0.71% has limited service to drive-through, carryout and delivery, as a result of the COVID-19 pandemic. The coffee and doughnut seller will remove tables and chairs from all its restaurants and outdoor patios to prevent the congregation of customers.

• Nordstrom Inc. JWN, -3.07% closed its U.S. and Canadian stores, including Nordstrom full-line, Nordstrom Rack, Trunk Club clubhouses and Jeffrey, for two weeks. The company’s online business, which accounted for one-third of sales in 2019, will remain in business. The company also withdrew its fiscal 2020 guidance offered on March 3, which didn’t include the impact of the coronavirus.

• Exxon Mobil Corp. XOM, -1.61% is “looking to significantly reduce spending” in the near-term as a result of market conditions caused by the pandemic and commodity price decreases. “We will outline plans when they are finalized,” CEO Darren Woods said in a statement.

• Dollar General Inc. DG, +2.26% is “strongly encouraging” that the first hour of store operations be dedicated solely for senior shoppers, who are the most vulnerable to infection. “Dollar General wants to provide these at-risk customers with the ability to purchase the items they need and want at the beginning of each day to avoid busier and more crowded shopping periods,” the company said in a statement.

• McDonald’s Corp. MCD, -1.03% has turned its U.S. company-owned restaurants into takeout only in the wake of COVID-19 and urged franchise owners to do the same. The fast-food giant also said it was closing its PlayPlaces indoor playgrounds. McDonald’s has 14,428 U.S. restaurants, with 93% of those owned by franchisees, according to the company.

Additional reporting by Ciara Linnane, Claudia Assis, Mike Murphy, Tomi Kilgore, and Wallace Witkowski

Read more of MarketWatch’s COVID-19 coverage:

Dow attempts to bounce back a day after coronavirus fears fueled a 3,000-point plunge

Global recession is expected this year: S&P Global

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