US health officials have reported that total deaths caused due to plague this year have reached four after the death of a 70-year-old man in Utah. Officials said the victim might have contracted the disease from a flea or contact with a dead animal.

JoDee Baker, an epidemiologist with the agency, said in a statement that the most common way to get infected is through flea or contact with a dead animal.

The rare disease which is spread by rodents and fleas is naturally occurring in Utah rodents and is often seen in prairie dog population.

As per Wildlife and health officials, an outbreak of bubonic plague killed 60 to 80 prairie dogs in an eastern Utah colony. The Centers for Disease Control and Prevention (CDC) also said 12 human cases had been reported in six US states since 1 April.

The other three people who have died have been reported to be of the age 16, 52 and 79, said officials.

According to the CDC's data, between one and 17 cases of the illness are been reported every year in the United Sates since 2000. Deaths due to it are rare, with no more than two a year having been recorded over the past 15 years.

Dr Paul Mead sad so far only four death cases have come across and this number is not at all a matter of alert. But said yes it is true that the number is twice as many, but when you're dealing with small numbers, you have that kind of variation.

Patients in a few of the 11 other cases this year came down with the plague after visiting Yosemite national park in California, noted officials.