The number of flea-born Typhus cases in Los Angeles has hit 107.
So far this year 72 patients have been recorded by Los Angeles County Department of Public Health with a further 15 in Long Beach and 20 in Pasadena.
In the 2000s there were around 20 cases recorded per year and analysts are putting the dramatic rise down to a 47 per cent increase in homelessness since 2012.
One official in Long Beach told NBC News that almost half a million potential cases are ‘under investigation.’
But no new cases have been reported there since October 5.
Flea-borne typhus occurs when faeces from an infected insect come into contact with a person’s cut or gets rubbed into their eyes.
These fleas often live on feral cats and rats who are attracted to areas with trash on the streets.
Most sufferers endure headache, fever and rash, however, in severe cases, typhus can lead to life-threatening hepatitis and internal bleeding.
Dr Ying-Ying Goh, Pasadena’s health officer, said: ‘Typhus fever is a disease that can cause serious complications requiring lengthy hospitalization, and rarely, death.’
She encouraged all residents in the city to take precautions in order to prevent fleas in and around their homes, CNNreports.
Dr Anne Rimoin, an associate professor of epidemiology at the University of California, told CNN: ‘Right now, it’s hard to speculate on why we are seeing more cases.