Eleven cases of the plague have been confirmed in the United States and three people have died since April 1, according to the Centers for Disease Control.
The cases have been reported in Arizona, California, Colorado, Georgia, New Mexico and Oregon. In an average year, there are seven confirmed cases of the plague.
The plague is a life-threatening illness that comes from fleas. Symptoms include sudden, onset fever, with stomach pain, nausea and vomiting.
Plague cases higher than usual, CDC says