Is an Old Virus Up to New Tricks?

EXOTIC DISEASESA recent upsurge of monkeypox cases in the Democratic Republic of Congo, in which the virus seems to have jumped from person to person more readily than before, is alarming some public health experts. One reason for the spread is that smallpox vaccinations--which also confer immunity to monkeypox--were so successful that they were stopped nearly 2 decades ago, creating an ever-growing pool of people who are susceptible to the animal virus.