THE HSE HAS ORDERED additional stocks of the flu vaccine in an effort to combat swine flu.

Some 30,000 new vaccines have been ordered as most of the around-650,000 doses delivered in September have been used up, the Irish Times reports.

During Christmas week, some 91 cases of the H1N1 virus were detected – more than double the number detected the previous week, the Health Protection Surveillance Centre.

Here is TheJournal.ie’s list of things you should know about swine flu:

1. Swine flu is just as transmissible as the seasonal flu

2. The H1N1 swine flu virus first emerged in April 2009 and accounted for 98% of all flu cases seen in Ireland last year

3. The World Health Organisation said last year that it regards vaccination as the most effective way to prevent flu infection. This year’s seasonal flu vaccine (available from GPs) includes protection against swine flu…

4. …but people with a history of severe allergic reaction to the vaccine or who are sensitive to eggs should not get the vaccine

5. Flu symptoms come on suddenly, according to the HSE, and include a fever, muscles aches, headache and tiredness. Side effects of the vaccine include soreness/redness at the point of vaccination, headaches, fever, sweating and tiredness, and should dissipate after a day

6. The flu affects the respiratory tract and people with pre-existing medical conditions, compromised immune systems, infants (especially under 2 years) and pregnant women are considered particularly at risk of infection

7. Most people will not experience severe infections and will be able to recover fully at home instead of receiving hospital treatment, the HSE says