Authorities in Tanzania have identified the mysterious outbreak that killed three people in the southern region of Lindi last week as Leptospirosis.

A team of health scientists had launched an investigation after the unexplained deaths of three people. Some of the symptoms exhibited by the victims included fever, headaches, fatigue and nosebleeds. The trio were among 11 people who had been diagnosed with the issue.

The country's Minister of Health, Ummy Mwalimu, on Monday said test results from samples of patients in Ruangwa, one of the districts in Lindi, were positive for the disease, which is also known as "rat fever".

Mwalimu added that more than 20 cases have so far been reported, while two patients are currently hospitalised. Contact tracing is underway.

"Up to now, no other person among contacts has shown any symptoms of the disease," she said.

Mwalimu also appealed to the public to remain calm noting that the disease was preventable and curable.

According to the Centres for Disease Control and Prevention (CDC), the bacteria are transmitted from animals to humans through cuts or abrasions in the skin, nose, or eyes that come in contact with water or soil contaminated with the urine of infected animals. However, the disease cannot be transmitted from one human to another.

(With input from agencies)