A second Kansas youth has died from E. coli contamination, but health officials say the two cases are isolated and do not indicate an outbreak.

A 4-year-old Chase County boy is the latest victim of the disease, dying Sunday at Wesley Medical Center in Wichita. A county health official says the unnamed boy's father is a rancher and the youth could have come into contact with cow manure.

An 18-month-old Liberal boy died Wednesday at the same Wichita hospital, and his brother was admitted with the same symptoms but is expected to be OK. Investigators aren't sure how the boys came into contact with the bacteria.

Infection control nurse Lois Rayhal says it only takes a little bacteria to cause diseases. She says the cases are a reminder that people need to wash their hands frequently, especially after coming into contact with cattle.