Last Christmas, my article expressed the same sentiments about getting the seasonal flu vaccine since the flu (short for influenza) is an unwelcome visitor this time each year. Ironically, last year Christmas, the swine flu and its vaccine were nowhere on our radar.

Fast-forward to Christmas 2009, and just as we are waiting to see Christmas and the New Year arrive, we are expecting the arrival of the H1N1 (swine flu) vaccine to Jamaica. Reports show, however, that there is a shortage of the vaccine worldwide.

Will the vaccine come to Jamaica?

Although it has been three months since the approval of the new H1N1 (2009) vaccine, here in Jamaica we do not yet have a scheduled date for its arrival. Hundreds of millions of doses have been manufactured by at least three manufacturers but it is still not enough to go around. We know, however, that the Government of Jamaica via the Ministry of Health (our national health authority) will regulate its distribution here.

What's in the vaccine?

When a person is given the vaccine, the immune system (the body's natural defence system) will produce its own protection (antibodies) against the disease. None of the ingredients in the vaccine can cause flu.

The vaccine consists of:

An antigen (in this case it is an inactive preparation of the flu virus). This pushes the body's defence mechanism to respond to the virus. The virus is inactivated so it won't give us the flu. The body will then produce antibodies, a protein substance to fight the antigen from the vaccine and any H1N1 (2009) virus which enters the body within a certain time frame thereafter.

An adjuvant, a chemical like aluminium hydroxide which increases the effectiveness of the vaccine. This may mean that less antigen is needed to produce the same vaccine. By extension, more doses of vaccine may be produced. The adjuvant may or may not be present in a vaccine. The only challenge is that vaccines with adjuvants tend to carry more side effects than those without. There are no flu vaccines with adjuvants licensed in the USA.

Who should be vaccinated?

Persons who are at risk of serious complications, like pneumonia, heart damage and dehydration, from the effects of the swine flu are regarded as being 'at risk'.

These people include children under five years old, the elderly, pregnant women, persons with diabetes, kidney and heart disease and those with a weak immune system, for example, those with HIV, cancer, and those undergoing chemotherapy or radiotherapy. Other at-risk persons are those with respiratory trouble, like asthma, bronchitis and emphysema.

Go ahead, have a happy Christmas

Don't allow any flu ('swine' or 'seasonal') to dampen your Christmas spirits. If you are at risk, as soon as the swine flu vaccine makes its appearance here, try to get yourself vaccinated. If you can, give yourself the gift of a flu vaccine. As for me, that's all I want for Christmas!

Dahlia McDaniel is a pharmacist and final-year doctoral candidate in public health at the University of London; email: yourhealth@gleanerjm.com.