The clinics were scheduled to wrap up at the end of this week but will now be extended for another week and may be kept open longer depending on demand, according to Fraser Health spokesperson Roy Thorpe-Dorward.

The Health Authority is also stockpiling 50,000 doses of vaccine to ensure it is prepared if the outbreak spreads farther west.

As of Tuesday, 110 cases of the highly infectious disease, also known as pertussis had been reported in the eastern Fraser Valley, including eight in Chilliwack.

A handful of whooping cough cases have also been reported in Maple Ridge, Langley and Surrey, but Fraser Health officials said it's not clear whether these are cases that normally crop up year to year or are part of the spread of the outbreak.

Chilliwack residents have been lining up the get the vaccine since Fraser Health expanded its pertussis alert to include Chilliwack, Agassiz and Harrison last month.

"More cases are cropping up, so I'm thinking it's a good thing, " said Lisa Mindel, who got the shot Tuesday along with her 13-year-old daughter Meghan at a clinic at Central elementary.

More than 2,000 people in the eastern Fraser Valley have been immunized at clinics and doctors' offices since the outbreak began.

"The best protection against pertussis is to get vaccinated," said Paul Van Buynder, Fraser Health's chief medical health officer in an earlier release. "Pertussis in very young children can lead to hospitalization and even death."

Whooping cough can be a severe illness in people without adequate immunization, and many adults are not protected because the vaccine they got as children is only effective for five to 10 years.

Early symptoms are like those of a cold with sneezing, a runny nose, a low fever and a mild cough, but over a week or two, the cough gets worse, leading to longer spells of coughing that often end with a whooping sound when the person breathes in.

In rare cases, pertussis can cause pneumonia, convulsions, brain damage and death.

Fraser Health is urging parents to ensure their children are fully immunized and is offering free booster vaccine to adults who are in regular contact with young children in Hope, Agassiz, Harrison Hot Springs and Chilliwack.

Adults who have not had a booster in the last five years are asked to contact their local health unit, their doctor or health care provider to receive the free vaccine.

? For more information about whooping cough, visit www.healthlinkbc.ca. To find out about clinics, contact your local health unit: Chilliwack, 604-702-4900; Agassiz, 604-793-7160, or Hope, 604860-7630.

cnaylor@chilliwacktimes.com