Scientists have warned that a rare bacterial disease that was only active in non-human animal species is now a threat to human health.

The disease is carried by rats, which are exceptionally common throughout both urban and rural environments, so the threat is quite substantial. One person has already died as a result of the disease, and two more victims were battling the illness in quarantine.

The disease in question is called leptospirosis, and all three initial cases were identified within one block of the Concourse region of the Bronx in New York City.

A cluster of this illness has never before been reported. The disease can lead to both kidney and liver failure, as well as pulmonary hemorrhage and even death. While only one of the three initial cases died, the others eventually recovered and were released from the hospital.

One of the victims was a man called Braulio Balbuena Flores, and he was in the hospital for more than two weeks with a bad fever, insomnia, general aches and pains, and a complete lack of appetite.

This is not the first time that leptospirosis has been seen in humans, but it is the first incident of several cases within such a small area.

In the previous 10 years, there were only 26 cases of the disease reported in NYC. That represents an average of about 2 or 3 cases per year, all spread throughout the city. These three cases occurred within weeks of each and were all within a single city block.