Influenza - A Basic Summary for 2011

Please refer to www.swineflu.ie for a comprehensive and up-to-date guide to this subject for Ireland. It has sections for both the public and health care professionals.

For all practical purposes, swine flu is the same as this year's seasonal flu, also known as H1N1. This year's regular flu vaccine protects against swine flu. Most cases of flu are swine flu. It is a relatively mild illness for most people. It is however always important to remember that there is an increased incidence of bacterial infections especially meningococcal disease as co-infections with the flu.

Who Should be Vaccinated?

• Please see the letter below from the HSE (18th January 2011) on Revised National Immunisation Advisory Committee (NIAC) Recommendations for Influenza Vaccine for Pregnant Women and Those up to Six Weeks Post Partum.

The people who should be vaccinated this winter (as in every other year) include those with chronic illnesses or debility, people over 65, health care workers, pregnant women and those who care for these vulnerable people. People in these groups who have not already been vaccinated for this winter should arrange to do so as soon as possible. Vaccination of pregnant women is advised because they are at particular risk of severe illness being caused by this flu. This advice is supported by obstetricians in Ireland and internationally. This can be done at any stage of pregnancy including up to six weeks after delivery but sooner is better. People outside the identified groups, including healthy children, do not need to be vaccinated.

Explanatory note: Because many people got either swine flu itself, or the swine flu vaccine last year, many will already be immune. Since no vaccine is 100% effective, some individuals vaccinated last year will not actually be immune and may get flu. Schoolchildren were targeted for vaccination last year, not because they are at particular risk of severe illness, but because vaccinating children has an additional beneficial effect for the overall community. The vaccination of otherwise healthy children this year is not required, but children with chronic illness, including those with significant intellectual or physical disabilities and those on regular treatment for asthma should be vaccinated this winter, even if they had the swine flu vaccine last year.

Diagnosis and Testing

Influenza is reliably diagnosed based on the patient having appropriate symptoms and signs while it is known to be circulating in the population. Common symptoms include the sudden onset of a fever, cough, sore throat, muscle pains, headache or sometimes vomiting. Some people with flu will not have a fever. Swabs or blood tests are not usually necessary to make a reliable diagnosis or to treat patients. These tests are mainly done in patients who require hospitalisation. Laboratory confirmed case numbers, as reported in the media, are only the "tip of the iceberg" but serve to confirm that influenza is circulating.

Treatment of People with the Flu

Most people who get the flu will recover after a few days with simple treatment such as paracetamol to relieve symptoms.

People with chronic illnesses/debility (including asthma), people over 65, children under two years and pregnant women who develop symptoms of influenza should seek medical advice at an early stage in the illness, ideally within 24 hours, because they are at increased risk of complications. Treatment with Tamiflu (Oseltamivir) will often be advised in these situations.

Otherwise healthy people with

• severe symptoms
• or who are not improving by the third day of illness
• or who seem to improve initially but relapse

should also seek medical assistance.

Complications of Influenza and When to Use Tamiflu® in the Community

Key Points:

• The current advice is not to treat uncomplicated influenza in patients outside the identified risk groups.
• The current advice is to treat patients in the high risk groups with Oseltamivir, ideally within 48 hours of onset.
• Even low risk patients and their carers need to be aware of the small chance of an abrupt deterioration, and to know what to look for, and then act promptly and effectively.
• Consider starting oseltamivir in patients with complications of influenza, with or without concurrent antibiotic cover.
• When referring patients with complications of influenza to hospital, consider giving a first dose of oseltamivir immediately to minimise further delay.
• Remain alert to the increased risk of meningococcal disease.
• Immunosuppressed patients are particularly vulnerable.

Please see the attached document for more information.

Reduce Transmission

You can protect yourself and others from becoming infected by:

• Washing your hands with soap and water. Alcohol rubs may be a convenient alternative but are not essential.
• Avoiding unnecessary exposure to people who are ill with influenza. Wearing a surgical mask may be helpful in reducing the risk while caring for someone with influenza. Dispose of it carefully and wash hands afterwards.
• Being vaccinated if you are part of the population for which it is advised.

If you get sick with flu, you can help protect others by:

• Catching your cough or sneeze in a paper tissue (or your sleeve if no tissue is available) -"Catch it!"
• Disposing of the used tissue safely (a regular waste bin is adequate) -"Bin it!"
• Washing your hands frequently, especially after handling the tissue. -"Kill it!"
• Attention to basic hygiene on adjacent household surfaces including door handles and bins.
• Minimising contact with others while you are ill, especially vulnerable people such as the elderly, infants or pregnant women. Patients are most infective when the symptoms are more severe, and the risk of transmission to others reduces as the symptoms resolve, typically over 5-7 days. In real terms, this may mean staying out of work or school while you are sick.

Detailed information is available at www.swineflu.ie.