Fraser Health has issued a warning that cases of measles have begun spreading outside of the previous school and religious groups where they first appeared, and are now showing up in Chilliwack and Agassiz.

The measles virus is passed through airborne droplets and direct personal contact. (U.S. Centres for Disease Control and Prevention)

Chief Medical Health Officer Dr. Paul Van Buynder says only one child has been admitted to hospital so far, but dozens of cases have also been reported in the general populations of the two Fraser Valley municipalities.

The health district says its warning includes all of Fraser Valley East, including Abbotsford, Mission, Chilliwack, Agassiz, Harrison Hot Springs and Hope.

Special vaccination clinics next week

Arrangements are being made to distribute increased measles vaccines to doctors and pharmacies in the area. Children under the age of five are most at risk of serious complications, and Van Buynder says they should be vaccinated right away.

Special vaccination clinics in Chilliwack and Agassiz are being organized for early next week and their locations will be available on Fraser Health's website.

Pregnant women should avoid the antigenic vaccine, but can seek protection with immunoglobulins, Dr. Meena Dawar said. (CBC)

Van Buynder is asking anyone with symptoms to isolate themselves at home.

“It is not necessary to attend a medical centre for testing to confirm measles during an outbreak unless you are quite sick," he said.

"We know there are measles circulating and laboratory confirmation is not necessary."

Van Buynder says people who are very sick should get to the doctor, but only after warning them that they are coming.

Tough sell in 'Bible Belt'

The health authority is facing some opposition to vaccinations in the Fraser Valley's so-called "Bible Belt."

This morning on CBC's Early Edition, Rev. Adriaan Geuze, a pastor at the Reformed Congregation of North America, questioned the effectiveness of vaccinations.

Fraser Health says children under five are most at risk of serious complications and should be vaccinated immediately. ((Dita Alangkara/Associated Press))

"Members of our congregation do not believe vaccinations are safe," he said. "They are worried about administering vaccines to our children and vaccination does not automatically mean you are immune to the disease."

He added: "The claim that by not vaccinating children, we are putting others members of the Fraser Valley at risk is quite strange. You are actually admitting that vaccination is not so effective after all."

What are the symptoms of measles?

Symptoms of measles may develop seven to 21 days after exposure to an infected person.

Symptoms include a high fever, runny nose, cough, drowsiness, irritability and red eyes. Small white spots may appear in the mouth and throat. A red blotchy rash begins to appear on the face three to seven days after the start of symptoms, then spreads down the body to the arms and legs. This rash usually lasts four to seven days. Symptoms generally last from one to two weeks.

READ: Fraser Health public service announcement on outbreak