U.S. officials continued the cautious process of reopening certain states and localities, which helped to bolster investor confidence on Monday even as the coronavirus’ toll mounted around the world.

As the federal government debated the next stages of a stimulus package to combat the economic effects of the COVID-19 crisis, more than 3 million individuals to date have been infected, with more than 200,000 dead globally.

In the U.S., the number of infections is nearing 1 million, and more than 54,000 have died. New York and New Jersey remain America’s two hardest-hit regions, but have seen a decline in rates of hospitalizations and deaths. In the Empire State, where Gov. Andrew Cuomo stated restrictions for certain parts of the state would likely extend beyond May 15. There are more than 288,000 cases in New York, and the Garden State now has more than 111,000 cases.

However, several states are eyeing a May reopening, with New York allowing construction and manufacturing to get back to work as of May 15. On Monday, Cuomo said an antibody survey showed that nearly 15% of state residents have the virus — with that number nearly 25% in New York City, the main vector of the state’s COVID-19 outbreak.

The linchpin of relaxing restrictive orders hinges on sufficient testing. In recent days, the discussion has shifted from testing citizens for the virus to trying to determine the extent to which some may have already been exposed, and as a result may have some measure of immunity.

The U.S. has now conducted more than 5.4 million tests — a significant increase in the past few days, but still not enough to safely reopen, some experts say.

In addition, the question of immunity remains an open question. If a person has the antibodies, it is unclear if that means they are immune from getting the disease ever again, after a few years, or if they can get it whenever it comes back if it is a seasonal outbreak.

Over the weekend, the World Health Organization recently said there is no evidence that if a person has the antibodies they are immune from a second infection.

Dr. Dara Kass, a physician at Columbia Medical Center, told Yahoo Finance the level of immunity that antibodies provide will play a role in vaccination trials.

"That frequency may actually play into the vaccination timeline,” she said, adding that even still, it wasn’t clear whether antibodies would provide blanket immunity for those who have them.

The FDA has approved four antibody tests, but more are expected to help meet the demand. Meanwhile, vaccine and treatment efforts continue globally.