One way scientists have described it is that a virus spilling over is, in a way, winning the lottery: The virus is in the right place at the right time, and on top of that, it has special, rare characteristics that allow it to infect people.
The Biden administration is planning to end the COVID-19 emergency declarations on May 11, and expects to run out of government-bought vaccines and treatments as soon as this summer and fall.
Because the medical condition is new and poorly understood, patients often consult multiple specialists who order a long sequence of tests to rule out other illnesses.
The PHE for the mpox outbreak that began last year is officially ending as of Tuesday, with the number of reported cases continuing to dwindle and advocacy groups declaring the emergency's conclusion a victory for the LGBTQ community.