Clinical trials worldwide suggest that up to 85 per cent of healthy adults who are vaccinated against the H1N1 swine flu virus will develop immunity within 10 days. (CBC)

The swine flu vaccine is now available in B.C. for those people who are most at risk from the H1N1 virus.

But healthy British Columbians are being asked to let those at high-risk be immunized first in order to ensure the most vulnerable are protected.

Starting Monday morning, clinics across B.C. will offer the vaccine for free to:

• Pregnant women past their 20th week.
• Adults under 65 with chronic medical conditions such as lung, heart, kidney or liver disease, diabetes or who are immunosuppressed.
• Persons — including First Nations people — living in remote and isolated settings or communities.

People who fall into these groups and for whom the seasonal flu vaccine is normally recommended will be able to receive both shots at the same time.

Starting the week of Nov. 2, the people eligible to receive the H1N1 vaccine will expand to include the following groups:

• All initial groups.
• Children six months to less than five years of age.
• Health-care workers (including all health-care system workers involved with the pandemic response or delivery of essential health services).
• Household contacts and care providers of infants less than six months of age, and persons who are immunocompromised.

In mid-November, everyone else who needs and wants the H1N1 vaccine will be recommended to receive it. Public notification will happen at this time so that everyone is aware the vaccine is available to them.

For adults, one dose of the vaccine is sufficient while kids under 10 years of age will still need two. The vaccine is not recommended for infants under six months old.

Recommendations for pregnant women

Health officials say women in the second half of their pregnancy are among those at highest risk of severe outcomes from the pandemic H1N1 virus.

While the unadjuvanted H1N1 vaccine is recommended for pregnant women, the adjuvanted version, available earlier next week, is approved for everyone who wants to protect themselves from this pandemic.

Since B.C. is experiencing epidemic levels of the H1N1 virus now, women in the second half of their pregnancy are advised not to wait until November for unadjuvanted vaccine, but to get immunized now with the adjuvanted version.

Adjuvants are compounds that boost the immune system's response to vaccine, allowing smaller doses to be used per person.

Seasonal flu shot still recommended

While it appears as if people born before 1957 have a much lower risk of contracting the H1N1 flu virus, the H1N1 vaccine is still recommended for everyone who needs and wants it, when it is available to them, say health officials.

After extensive consideration at the national level, B.C. and the provincial health officer are recommending that those British Columbians who normally receive the seasonal flu vaccine now be able to receive that vaccine at the same time as their H1N1 shot.

Guillain-Barré Syndrome (GBS), a form of paralysis that is usually temporary and can occur after some common infections, may be associated with seasonal influenza vaccine in about one per million recipients. It is expected that a similar pattern may be seen for the H1N1 influenza vaccine, say health officials.

So far, nine deaths in B.C. have been linked to the swine flu and an estimated total of 111 people have been hospitalized with the disease.