Local health officials are urging residents to take precautions against pertussis, also known as whooping cough, due to a resurgence of the illness, especially in the Baldwin City area.

The Lawrence-Douglas County Health Department reported 23 cases of pertussis in October and is investigating additional cases.

So far this year, 84 cases have been reported in Douglas County, compared to 17 cases in all of 2011. Statewide, there have been 588 cases so far this year, compared with 52 in 2011.

Pertussis is a contagious respiratory disease caused by bacteria. It spreads through coughing or sneezing in proximity with others.

Symptoms are similar to those of the common cold: runny nose or congestion, sneezing and occasionally a mild cough or fever.

Infants and children with the disease may cough violently and rapidly, over and over, until the air is gone from their lungs and they’re forced to inhale with a loud “whooping” sound.

In rare cases, about 1 out of 200, pertussis can be fatal, especially in children age 1 and younger.

To stop the spread of pertussis, health officials recommend:

• Contacting your physician by phone if you have any symptoms.

• Taking all medication if recommended and isolating yourself.

• Staying home when you are ill.

• Covering your cough.

• Ensuring you and your children are up to date on immunizations for pertussis. The immunizations are commonly known as DTaP or Tdap.

The health department offers pertussis vaccines through its walk-in clinic, 200 Maine St. Some adults may be eligible to receive the vaccine at a reduced rate if they meet certain income guidelines.

For clinic hours, visit the health department’s website at www.ldchealth.org/contact.