A sad milestone was reached this week, with the Ray Pfeifer Foundation reporting that 200 New York City firefighters have now died from "9/11 illness."

The foundation, which provides assistance to 9/11 first responders with medical bills not covered by insurance, said that Dennis Gilhooly, a retired FDNY captain, and Brian Case, a retired firefighter, are the 199th and 200th FDNY deaths related to the attacks on the World Trade Center, CBS News reports.

Toxins were released when the World Trade Center towers collapsed, and more than 50,000 people who were exposed have become sick, CBS News says. Studies have found a high number of deaths from non-Hodgkin's lymphoma and brain malignancies among 9/11 first responders and others who were exposed to the dust cloud after the towers fell. Catherine Garcia

Mort Drucker, the beloved artist known for his work at MAD magazine, has died at 91.

Drucker died Wednesday at his home in New York, his friend John Reiner confirmed to The New York Times. Reiner told CNN's Jake Tapper his death was not thought to be related to COVID-19.

After joining MAD in 1956, Drucker's hilarious caricatures satirizing pop culture soon became iconic, and he illustrated more than half of the magazine's movie parodies from the 1960s through 2008, per the Times. In a 2000 interview with the Times, he noted, "I think I've drawn almost everyone in Hollywood."

Among Drucker's other notable work includes the poster for George Lucas' American Graffiti; according to The Hollywood Reporter, Lucas personally drove to Drucker's home on Long Island to convince him to draw it.

"The World has lost a not just an extraordinary talent but a shining example of kindness, humility and humor," the National Cartoonists Society said in a statement.

MAD fans on Thursday quickly began sharing their favorite cartoons from Drucker's legendary career, including his parodies of Jaws and Star Wars. "Many of his illustrations are as vivid in my mind as the movies and TV shows that inspired them," The New York Times' Dave Itzkoff wrote.

Reiner told CNN's Jake Tapper that Drucker's final words to him were, "I'm the luckiest man — I've had a wonderful life." Brendan Morrow

First lady Melania Trump is officially donning a face mask during the COVID-19 pandemic, although the jury's still out on whether her husband will follow suit.

In a social media post Thursday, the first lady shared a photo of herself wearing what appears to be a surgical mask, touting the Centers for Disease Control and Prevention's recommendation "to wear cloth face coverings."

"Remember, this does NOT replace the importance of social distancing," she wrote. "It is recommended to keep us all safe."

Melania's masking comes one week after President Trump announced he would not be wearing a mask, despite the CDC-issued guidelines urging people to do so. At the time, Trump implied that it would be odd to be "sitting in the Oval Office, behind that beautiful Resolute Desk" while wearing a mask, so it's unclear how he's taking this news.

The photo of the first lady appears to show her wearing a surgical mask rather than the CDC-recommended "cloth face covering," the former of which is recommended only for use by health care professionals and medical first responders amid critical supply shortages.