Joe Palca

Historically tobacco plants are responsible for their share of illness and death. But two companies are using the plants to produce proteins for a vaccine. One candidate vaccine is in clinical trials.

A new study estimates the pandemic could cause over 400,000 deaths in the U.S. this year. It includes those who died of COVID-19 and people who died due to disruptions caused by the pandemic.

Large-scale safety and efficacy trials of experimental vaccines in tens of thousands of volunteers are underway. Answers about the trials are likely to come late this year.

President Trump sounded upbeat after being released from the hospital, and announced in a video that people should not be afraid of the virus. His treatment regimen is not available to most people.

The president's doctor has offered a fairly upbeat assessment of Trump's condition. But typically, only hospitalized COVID-19 patients in need of oxygen are given the drug.

The president has been receiving a steroid, an antiviral medication and an experimental drug cocktail. He's also received supplemental oxygen.

White House physician Sean Conley says that President Trump was doing "very well" and that the symptoms he had are resolving and improving.

There are no proven treatments for patients with COVID-19, and the treatments that do exist tend to be used on patients with advanced illness.

The Defense Advanced Research Projects Agency is sponsoring a program to develop effective medical countermeasures to a pandemic. The coronavirus pandemic gave those plans a real-life challenge.

Volunteers getting the shot help determine if a candidate vaccine works. But what with social distancing and masks, scientists must discern if it's the shot or these other measures preventing illness.

Over 100,000 people worldwide are taking part in coronavirus vaccine trials. NPR answers common questions, such as why so many people are needed and what it means to say a vaccine works.

David Legates, a professor whose research has been supported by fossil fuel companies, has been hired for a top position at the federal agency that oversees weather and climate forecasting.

The company had placed its worldwide vaccine trials on hold for several days. It now says a safety review by regulators and reviewers is complete. No word on when studies in the U.S. might resume.

AstraZeneca, which is working with the University of Oxford, hasn't said what the illness is. It will try to determine whether the illness is related to the vaccine, or just a chance event.

Scientists and engineers in California are building a unique 3.2 billion pixel camera for a telescope under construction in Chile. The camera has taken its first test pictures — of broccoli.

Several COVID-19 vaccine candidates are being tested now. But why does it take 30,000 volunteers to know if one is safe and effective? And what does it mean to say a vaccine candidate is working?

Several COVID-19 vaccine candidates are currently under testing to see if they prevent the disease. What determines if a vaccine works and why does it take 30,000 volunteers to figure that out?

A vaccine against the coronavirus needs to keep people from getting very sick and dying. But preventing the spread of the disease is also important, and vaccines delivered by nasal spray may do that.

New vaccines usually take years to get the approval of the Food and Drug Administration. But the Trump administration suggests the FDA may greenlight a coronavirus vaccine by the end of the year.

New vaccines usually take years to get the approval of the Food and Drug Administration. But the Trump administration suggests the FDA may greenlight a coronavirus vaccine by the end of the year.