Here's how the US handled its first ever monkeypox outbreak that infected dozens of people across several states

Contact tracers found that all 35 human cases of monkeypox were traced back to contact with prairie dogs obtained from an animal distributor in Illinois, according to the CDC. 

The prairie dogs from the Illinois distributor "appear to have been infected through contact with Gambian giant rats and dormice that originated in Ghana" and were purchased by the distributor, the CDC found at the time. 

In addition to ordering quarantines, the CDC issued a joint order with the Food and Drug Administration to ban importing rodents like prairie dogs.

The CDC also recommended animal euthanasia for all the rodents that came in contact with the infected shipment of prairie dogs, according to the archived CDC site. 

"These animals are considered to pose a continued risk for infection for other animals and humans," the agency said at the time, per the site. 

On May 7, the UK Health Security Agency confirmed a case of monkeypox in a patient who had traveled from Nigeria to the United Kingdom.

As of May 20, the UKHSA has detected 20 cases of monkeypox since May 6.

The virus has since been detected in the US, Canada, Australia, Belgium, France, Germany, Italy, Portugal, Spain, and Sweden, per the World Health Organization.