A total of 22 people contracted the illness between March 8 and mid-May, state officials said.
The state is working with the federal Centers for Disease Control and Prevention to investigate the outbreak. State officials have declined to name a town within Union County where the outbreak may have started while it works the federal government on the investigation.
Up to 300 people a year in New Jersey contract Legionnaires, which is contracted by breathing in tiny water droplets infected with the bacterium that causes it. The disease grows in decorative water fountains, certain types of air conditioning units (but not home air conditioners) and water towers. It is not contagious and can usually be treated with antibiotics.
Symptoms may include fever, cough or diarrhea and may take up to two weeks to develop. Anyone who develops those symptoms and lives in or has visited Union County recently is urged to see a doctor.
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