If you have had chickenpox, the virus that caused it is still with you. It rests in nerve tissue and can reactivate decades later as shingles. Québec's health ministry puts the lifetime figure at one in three people. This guide explains who the vaccine is for, how the two doses work and what the days after a dose look like.

What shingles is

Shingles is a reactivation of the varicella-zoster virus, the same virus that causes chickenpox. It usually appears as a band of blistering rash on one side of the body, along the path of a single nerve.

For some people the pain continues for months after the rash has cleared. This is called postherpetic neuralgia, and it is the main reason the vaccine exists. The chance of shingles rises with age, as the immune memory that keeps the virus at rest fades.

How the vaccine works

The vaccine used today is recombinant, not live. It contains a single protein from the surface of the virus, along with an adjuvant that helps the immune system respond strongly to it. That rebuilds the immune memory that the years have worn down.

Because it is not a live vaccine, it can be given to adults whose immune system is weakened, with a physician's review.

Who it is recommended for

The Canadian Immunization Guide recommends it for adults aged 50 and over, and for adults 18 and over who are or will be immunocompromised.

Two groups often ask whether it still applies to them. If you have already had shingles, it does: shingles can come back, and the guide suggests vaccination can be considered at least one year after the episode. If you received the older live vaccine, the two-dose series is recommended as well, at least one year later.

The vaccine is not given during an active shingles rash, to anyone with a known severe allergy to one of its components, or on a day when you have a fever.

Two doses, and how they are spaced

Two doses are needed. The Canadian Immunization Guide sets them two to six months apart, and Québec's program accepts an interval of two to twelve months. If your second dose is late, the series is not restarted. You simply receive the second dose.

For someone whose immune system is weakened, the second dose can be given sooner, as early as four weeks after the first. The physician sets the interval that suits you.

How well it works

According to the Canadian Immunization Guide, efficacy stays above 90 percent in the four years after vaccination, in every age group, and remains over 70 percent up to ten years later. Québec's health ministry adds that when shingles does occur after vaccination, the risk of lasting nerve pain is reduced by 90 percent.

What to expect after a dose

This vaccine produces more of a reaction than most, which is a sign of the immune response it is designed to create. A sore arm is the most common effect and is reported by more than half of people. Tiredness, muscle aches, a headache or a mild fever are also common and last a day or two.

Québec's data show that for about 17 percent of people, these effects are enough to set aside usual activities for a day or two, a little more often after the second dose. Many people choose a day when they can take it easy. Difficulty breathing or swelling of the face is rare and needs urgent care.

Public coverage in Québec, and private vaccination

At the time of writing, Québec offers the vaccine free of charge to people aged 71 and over and to immunocompromised adults 18 and over. Adults aged 50 to 70 can be vaccinated at their own cost. Eligibility has changed more than once, so the current rules on Québec.ca are worth a look before you book.

At Clinique Medix, shingles vaccination is offered by appointment. A physician reviews your history before the dose, the dose is recorded in your medical file, and you stay about fifteen minutes afterwards.

Before your appointment

Bring your vaccination record if you have one, and a list of your medications. Eat and drink beforehand, and wear a short sleeve, since the dose goes into the upper arm.

Clinique Medix is at 1220 Bernard Avenue in Outremont. To book, contact the clinic and the team will call you back.

FAQ

Do I need both doses of the shingles vaccine?

Yes. One dose gives partial protection, and the second is what makes it last. They are given two to six months apart, and a late second dose does not mean starting over.

I have already had shingles. Should I still be vaccinated?

Yes. Shingles can come back. Vaccination can be considered at least one year after the episode, and the physician confirms the timing.

At what age is the shingles vaccine recommended?

From age 50, and from age 18 for adults who are or will be immunocompromised.

Is the shingles vaccine free in Québec?

At the time of writing, it is free for people aged 71 and over and for immunocompromised adults 18 and over. Adults aged 50 to 70 pay for it.

What are the common side effects?

A sore arm, tiredness, muscle aches, a headache or a mild fever for a day or two, a little more often after the second dose.

The shingles vaccine: who it is for and how the two doses work