It was one heck of a Thursday for the Johns Hopkins Hospital researchers in Baltimore, Maryland, after a tuberculosis (TB) scare evacuated multiple buildings.
At around 12 pm, a vial of frozen Mycobacterium tuberculosis was dropped onto the floor in an internal bridge that connects the hospital's Cancer Research Building 1 to Cancer Research Building 2.
When the vial dropped, the lid came off. Not long after, someone pulled the fire alarm and employees were quickly evacuated.
As Sarah Meehan and Lauren Lumpkin from the Baltimore Sun explains:
"Nearly a dozen fire vehicles surrounded the hospital's cancer research centre Thursday afternoon.
"A hub of white tents, which usually hosts the hospital's weekly farmers' market, was converted into a waiting area for those evacuated from the building."
There were employees in the area where the spill occurred, but hospital officials believe that no one was exposed to the bacteria, and no one was treated.
"I don't think I'm going to have an appointment this afternoon, the way it looks," said Murphy Davis, a patient of the hospital, to WBAL at the time.
While we don't know the details of why the sample was in a hallway, the part of the hospital it was in is a research section, and the Center for Tuberculosis Research is one of the institutes in those buildings.
TB is a disease that most commonly infects the lungs; in most cases, it usually stays dormant, remaining hidden and not infecting anyone else.
But in a proportion of people carrying the bacteria, the disease manages to find a way around the immune system's defences, and M. tuberculosis will actually reproduce inside white blood cells.
These dead white blood cells then cause the irritation that leads to one of the most well-known symptoms, the bloodied cough.
"There was a small tube that contained a frozen sample, and it was dropped and the lid came off while the sample was still frozen inside," Landon King, executive vice dean of the Johns Hopkins School of Medicine said to WBAL.
The sample being frozen is a good thing in this situation, as frozen bacteria can be stored and revived for later use, but it's harder for the biological material to spread or become infectious.
"We have determined there is no risk involved," King, told the Baltimore Sun.
King said the sample that leaked was "equivalent to a few drops".
The building reopened several hours later at around 4:20 pm.
We're glad everyone is okay, and although it was probably inconvenient, it's always better to be safe than sorry when it comes to dangerous diseases.