This is the second confirmed case of the measles at Kennebecasis Valley High School. The first was confirmed on May 13.
Video: Do you need a booster vaccine to guard against the measles? Theres a recommended age group
“We know that if somebody is exposed to measles during the time that someone is contagious that if you get a dose of the vaccine within 72 hours, that it’s protective against measles.”
GNB is offering immunization to staff and students potentially exposed to measles at KVH. All three confirmed cases are in the Saint John region, you're being reminded to check vaccination records. @Global_NB pic.twitter.com/Wc1HH61wBx
The first case in Saint John was confirmed last month in an individual who recently travelled internationally.
Chief Medical Officer of Health, Dr. Jennifer Russell, said the vaccination is not mandatory, but she confirmed the message to staff and students is they must receive the booster shot or they cant go to the school.
The New Brunswick Community College reported a suspected case of the measles last week, but tests came back negative.
The Department of Health is asking those potentially exposed to the measles to check their immunization records or contact their health-care provider.
Measles is a highly contagious infection and can be prevented with a vaccine. Most people who contract the virus make a full recovery.
FREDERICTON — New Brunswick health authorities are advising staff and students at a high school near Saint John that they must receive a measles booster shot if they want to continue going to the school.
There is a second confirmed case of measles at Kennebecasis Valley High School in Quispamsis, bringing the total number of cases of the highly contagious respiratory disease in the Saint John region to three.
Public health scrambled to offer the measles, mumps, rubella (MMR) vaccine to all KVHS students and staff Friday, regardless of their previous immunization history.
The agency adds that one or two out of every 1,000 children who are infected with the virus will die from respiratory and neurological complications.
"We know that if somebody is exposed to measles during the time that somebody is contagious — that if you get a dose of the vaccine within 72 hours, that is protective," the province's chief medical officer of health, Dr. Jennifer Russell, said during a news conference in Fredericton.
The latest case was confirmed Thursday night, according to an advisory emailed to parents Friday at 7 a.m.
The directive follows news of a third confirmed measles case in the Saint John area — the second at Kennebecasis Valley High School.
Because of the short notice about the clinic, students were allowed to sign their own immunization consent forms.
A doctors assistant prepares a measles vaccination in Berlin, Germany, Tuesday, Feb. 24, 2015. (Lukas Schulze/THE CANADIAN PRESS/AP)
Although Russell was "encouraging" all students and staff to get the shot on Friday, it was not mandatory, Department of Health spokesperson Bruce Macfarlane clarified near the end of the school day.
"Over the course of the day and with the tremendous turnout at the school clinic, Public Health believes that we have created sufficient herd [or community] immunity to protect most students and staff," he said in an email to CBC News. "As such Public Health will not be excluding non-participants but thank those that did accept the vaccine."
According to the Public Health Agency of Canada, because measles spreads so easily, at least 95 per cent of people need to be vaccinated for so-called herd immunity to work.
The notice sent to parents Friday by Anglophone South School District superintendent Zoë Watson said, "Students and staff who do not receive the vaccine may be excluded from school for 21 days."
Ten additional public health nurses were brought in from outside the region to help with the special immunization clinic.
Immunization clinics were held at the school May 16-17, but those vaccines did not provide retroactive protection because they were not administered within 72 hours of possible exposure, Russell said. They would, however, protect recipients from future events, she said.
Those who received the MMR or another live vaccine within the last month were advised not to get the MMR shot on Friday.
Individuals who are immunocompromised or pregnant should not receive a live vaccine and are being asked to stay home from school until public health can offer further advice.
The second KVHS case was exposed within the past 72 hours to the first one at the school, announced on May 13, she said without elaborating.
And the first infected individual at KVHS was at the Saint John Regional Hospital's emergency department at the same time as the first confirmed case, announced on April 26.
That person had recently travelled to Europe and visited the Halifax Infirmary's emergency department on April 17 for unrelated symptoms.
"There is no blame or responsibility here," said Russell. "These are things that happen that are outside of our control.
"People who go to another country or travel on a plane, where they are exposed to measles, it's not their fault. And so, being exposed in a setting like an emergency department, we're not blaming anybody, it's nobody's fault. These are things that just happen."
An unspecified number of teachers, staff and students at 19 schools across the Anglophone South School District were told earlier this week to stay home until early next week because they may have been exposed to the infected individual at Kennebecasis Valley High School.
They could be incubating the disease that's transmitted through the air or by direct contact, officials said.
About 500 teachers and staff from the various schools attended a New Brunswick Teachers' Association meeting at KVHS on May 6, officials said.
Grade 8 students from Harry Miller Middle School and Quispamsis Middle School and their parents went on a tour of KVHS on May 8.
Education Minister Dominic Cardy said earlier this week he isn't ruling out mandatory immunization for teachers and school staff in the province.
"That's certainly a conversation that will be had going forward," he told CBC News. Russell said now is not the time for that debate.
Liberal education critic and Victoria-La Vallée MLA Chuck Chiasson said it's important to know that number before making any decisions.
"I think it's a good thing that we assess the size of the problem to see how serious it is," he said in an emailed statement.
"The safety of the students will always be the priority, but there are certain charter rights that need to be taken into consideration."
New Brunswick and Ontario are the only two jurisdictions in Canada that require students to prove they are immunized against several diseases, including measles, mumps and diphtheria, before they enter the school system. Some exemptions are granted for medical or personal reasons.
Measles symptoms, which usually begin within eight to 12 days after infection, may include fever, cough, runny nose, red or sore eyes, sleepiness, irritability and tiny white spots in the mouth.
Within three to seven days, a red blotchy rash usually develops on the face and then spreads to the rest of the body.
Anyone exhibiting symptoms should call ahead before visiting their doctor's office, a clinic or emergency room so proper measures can be put into place to prevent the possible spread to others, said Russell.
Most people with measles recover completely after about 10 days, but complications can include ear infections, pneumonia, blindness and swelling of the brain, which can cause seizures, deafness, brain damage or death.
In New Brunswick, children are routinely immunized against the measles with two doses of MMR, at 12 months and 18 months. Both shots provide nearly 100 per cent protection.
But some people born between 1970 and 1995 have not had the recommended second dose. One vaccine is about 85 per cent effective.
A dedicated phone line has been set up to help people check their immunization record — 643-6251.
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