LOS ANGELES (MCT) — National Park Service officials and public health authorities are considering notifying visitors from other countries about a recent outbreak of hantavirus at Yosemite National Park that has killed two people and sickened at least one other.

Earlier this week, park officials emailed some 1,700 visitors who stayed in cabins in Yosemite's Curry Village between mid-June and late August, said park spokesman Scott Gediman. Letters were sent to visitors whose email addresses were not on record.

Dr. David Wong, an epidemiologist with the National Park Service's Office of Public Health, said Wednesday that officials were still trying to determine how many of those 1,700 visitors were from out of the country.

If that number is a "sizable population," he said, officials would consider asking the World Health Organization to help broaden the warning beyond the U.S.