The coronavirus has infected nearly 2.4 million people and killed more than 160,000 worldwide, according to the World Health Organization. As countries around the world, including the United States, grapple with how to contain COVID-19, new research is emerging on how the virus impacts the body both during infection and after recovery.

Watch the livestream in the player above.

PBS NewsHour correspondent William Brangham and Science Magazine writer Jon Cohen answered some questions about COVID-19 and what we know so far.

What does the virus do to our bodies?

Though news images of coronavirus patients being wheeled into an ambulance have become commonplace, a lot of people don’t know exactly what the virus does to the human body. While the coronavirus can cause flu-like symptoms, Cohen says it works a little differently.

“The fundamental thing it does is that it starves us of oxygen,” he said.

A lack of oxygen could lead to blood clots, which can create problems in the heart, as well as strain on other organs and extremities. It may even affect blood flow to the brain.

“Everything needs oxygen,” he said.

Are we getting close to a plateau of cases?

While some places in the world are certainly “flattening the curve,” others are still seeing a rise in cases, which means there isn’t a single, global measure of how much the infection is under control.

The biggest question for many is whether social distancing measures across the U.S. have been effective and whether Americans are reaching a plateau of cases — suggesting the virus might be receding or that life could soon return to a more normal flow. Cohen recommends a different perspective.

“I think we have to conceive of the pandemic as many pandemics,” he said.

While some places in the world are certainly “flattening the curve,” others are still seeing a rise in cases, which means there isn’t a single, global measure of how much the infection is under control.

“We will continue to pulse as the virus goes away and comes back until we can come up with biomedical strategies that are going to push it away for good,” he said.

Can you be infected by a new strain?

The nature of the virus is still being studied, both how it attacks a body and how it spreads.

An early study from China found that when rhesus monkeys were re-exposed to the virus after being infected, they did not contract the virus again. Researchers have theorized that humans will develop some level of immunity for some period of time once their body develops antibodies. Cohen, however, emphasizes that we still have a lot to learn.

“It’s maddening to people that we don’t have a firm answer,” he said.

Cohen said that’s why an overabundance of caution is the safest way to prevent the spread of the illness — that means even if you are exhibiting mild symptoms — or none at all — you should err on the side of caution, stay home and practice good hygiene.

What does a second wave look like if we don’t have a vaccine?

As states begin the process of considering how and when to reopen their economies, many fear another wave of infections and deaths.

“It can hit really hard when it comes back,” Cohen said. The key to avoiding more deaths, he added, will be to continue the same measures we’ve been taking: maintaining social distancing and protecting those who are vulnerable.

“Just be prepared for a lot of difficulty,” he said.

Despite the urgency to get the country working again, Cohen emphasized how complicated it is to create a treatment, and how long it takes to run through clinical trials.

“Viruses are really hard to stop,” he said.

Luckily, the global collaboration to find treatments for this virus shows promise for a quick turnaround on a solution.

“I’ve never seen this rapid of a response to a pandemic,” Cohen said.

Will the virus mutate?

As research and resources pour into the development of vaccines, some members of the public may be worried that the mutating nature of viruses may hinder that work.

Cohen, however, says this type of coronavirus actually doesn’t mutate quickly, at least compared to a virus like influenza.

He also explained that the mutation of the virus is only part of the equation. Much like the flu, the key is how much immunity coverage the vaccine would create.

What preventative measures are effective?

While treatments are still being developed, people are looking for ways to boost their immune systems or fight the infection themselves.

When asked about which over-the-counter medicines would help, Cohen said it is imperative to ask your doctor.

“If a journalist answers that question for you, be careful,” he said. “A journalist doesn’t know your medical history.”

That said, Cohen gained some insight when he spoke with George Gao, director-general of the Chinese Center for Disease Control and Prevention in March.

Back then, Gao told him the biggest mistake the U.S. is making is downplaying the importance of wearing masks. In recent weeks, the Centers for Disease Control and Prevention has changed their guidance to suggest that everyone should wear face masks or coverings in circumstances when social distancing is not possible.

While medical grade masks (like N95 masks) should be reserved for health care workers, fabric masks made at home can also be worn to prevent the virus’ spread.

“If you’re wearing a face covering, and you are sick, you’re less likely to transmit it,” said Cohen. He also suggests wearing a mask while you’re out in order to help normalize them, while also inspiring a “tinge of fear” that the virus is something to take seriously.

“Fear can be a positive thing to remind people what we’re dealing with,” he said.

Cohen also said there could be a certain charm to the masks, especially the creative hand-sewn patterns some have created.

“As ugly as this situation is, there’s some beauty in it as well,” he said. “We need some levity in these very serious times.”