There is evidence that the cockroach, also known as a roach, has inhabited this earth as far back as 350 millions years ago. To say it is a survivor and highly adaptable to changing environments is certainly an understatement. If an environment is suitable for humans, it is suitable for cockroaches. There are over 3,500 species of cockroaches and they distributed worldwide.
Cockroaches have been reported to spread bacteria and other pathogenic organisms such as Salmonella and Cholera simply through traveling from a contaminated source to another.