ANALYSIS:As the virus really starts to bite, our watchwords must be hygiene and perhaps vaccination
THE LATEST figures from the Department of Health are a clear indication the outbreak of pandemic H1N1 in the Republic has accelerated considerably. At 158.8 cases per 100,000 people, the rate of swine flu infection is greater than any seen in seasonal influenza since surveillance commenced in 2000. Those aged five to 14 and, to a slightly lesser extent, the under-fours, are taking the brunt of the infection, with eight in 10 cases hitting under 35s.
Despite rising prevalence, the H1N1 virus remains a mild infection for the vast majority of those who get it. Most will recover by staying at home for seven days, taking paracetamol and drinking plenty of fluids. A small number may require treatment with anti-virals at home, with just the occasional person requiring hospital admission because of complications. The most serious of these are pneumonia, acute respiratory distress syndrome and kidney failure. Of those admitted to hospital, about 45 per cent have a pre-existing condition.
It is early days yet and we are likely to see a number of waves of infection throughout the winter months. Experience in other countries suggests these waves peak after two to six weeks. There is useful information emerging from Australia and New Zealand, countries just coming out of winter which have experienced a similar period to the one we are entering.
Investigators from New South Wales provide perhaps the most comprehensive description of the pandemic using multiple surveillance systems. The pandemic there lasted 10 weeks and had a substantial impact on intensive care units (ICUs), with an increased risk of severe illness, including respiratory failure, in those aged between 35 and 60. Vulnerable groups included pregnant women, indigenous people, those with chronic respiratory disease, and those with morbid obesity. However, the good news is the general influenza-related mortality between April and September 2009 was lower than that seen during the same period in recent years, which suggests the H1N1 virus carries a lower mortality rate than regular seasonal influenza.
The swine flu stretched health services in the southern hemisphere to their maximum. In Australia and New Zealand, ICU admissions due to confirmed infection with pandemic influenza reached a maximum of 20 per cent capacity during the most intense weeks of the pandemic.
We will experience similar pressures here, with the cancellation of routine clinics and operations at certain times. But the most important message for now is to renew hygiene efforts and for those of us at risk of complications to attend for vaccination.