70 NATIONAL GEOGRAPHIC
By the time infectious disease
specialist Michael Callahan
climbed aboard the Grand
Princess in early March,
he was already an old hand
in the COVID-19 pandemic.
He’d gotten his start in
January trading notes in
his tightly knit network of
fellow experts about the
emerging pathogen in Wuhan,
China. He saw patients in
Singa pore as the disease
was breaking out there, and
he briefed U.S. government
officials in Washington, D.C.,
on where it might occur next.
He helped evacuate a cruise
ship in Yokohama, Japan.
Present Day