Two types of influenza adding to current wave of infection
Analysis: both types of flu are covered by this year’s vaccine
A girl is vaccinated against influenza at the General Hospital of the West in Zapopan, Jalisco, Mexico, last Monday. Photograph: EPA/Ulises Ruiz Basurto
The outbreak of swine flu at Cork University Hospital mirrors the increase in influenza-like illness seen in the community in recent weeks.
The hospital said it had one confirmed case of the H1N1 flu virus but reports from the Health Protection Surveillance Centre suggest another influenza A type (H3) is also contributing to the wave of infection.
We also know that influenza A(H1) and A(H3) are co-circulating across Europe. Both types of flu are “covered” by this year’s vaccine, which is available free from GPs for all people in at-risk groups, and from pharmacists for everyone aged 65 and over.
Flu rates, as measured by a network of “sentinel” general practices, have increased from 20.5 per 100,000 of the population to 32.4 per 100,000. There has also been an increase in flu-related deaths. But rates are not yet at epidemic levels.
When samples from patients are analysed by the National Virus Reference Laboratory, many turn out to be other respiratory viruses. These cause flu-like symptoms but generally do not result in the absolute prostration often seen with full-blown flu. In people with chronic underlying disease, especially those aged over 65, complications from flu are common.
Currently available influenza vaccines provide 70-90 per cent protection against influenza in people aged under 65. While efficacy in older people is lower, the vaccine lessens the severity of the flu.
What should I do if I think I have the flu?
Symptoms of seasonal flu include sudden onset of fever, cough as well as sore throat, aching muscles and joints. If you think you are coming down with flu, it’s best to isolate yourself in bed. Drink plenty of fluids and take paracetamol to reduce your temperature. Most people will recover with self-care in about a week to 10 days.
However, if you develop any of the following, then it is important to seek medical advice: increasing difficulty breathing, for example inability to complete a sentence; sharp chest pains that make it difficult to breathe or cough; thick yellow or green phlegm or brown or bloody phlegm; severe earache; uncharacteristic changes in behaviour such as becoming confused or appearing terrified (particularly in children); and being so drowsy as to have difficulty eating, drinking or speaking.
How do I know if I am in an at-risk group?
People with pre-existing health conditions such as heart and lung disease as well as those with chronic liver and kidney disease are at greater risk from influenza. If you have diabetes or a chronic neurological disorder you are considered at risk. Pregnant women are also advised to seek vaccination.