Schoolchildren and their parents should be the first members of the population to be vaccinated against swine flu to best prevent its spread, according to research.
The recommendations come as the government figures showed the number of people being diagnosed with the virus in the UK is now falling steadily, with an estimated 11,000 new cases in England last week, down from 25,000 the week before.
The vaccination study by American scientists, published yesterday in the online version of the journal Science, concluded that the most effective way to protect the population would be to prioritise the immunisation of school pupils and their parents, as these groups are most likely to transmit swine flu to others.
The researchers looked at data collected during earlier flu pandemics in 1918 and 1957, in an attempt to locate the groups of people who would be best to target with a vaccine.
“We find that optimal vaccination is achieved by prioritisation of schoolchildren and adults aged 30 to 39 years,” the scientists wrote. “Schoolchildren are most responsible for transmission, and their parents serve as bridges to the rest of the population.”
The advice contradicts the Government’s plans for a mass immunisation campaign beginning in October, which is due to prioritise people with chronic health conditions, pregnant women and pensioners. A decision has yet to be taken about whether the rest of the population will receive injections.
The number of UK swine flu-related deaths currently stands at 59, with 10 occurring in the past week. In England, there are 263 patients being treated in hospital, down from 371 reported last week. Almost half of those who have died lived in London.
The government’s chief medical officer Sir Liam Donaldson said yesterday that it was “virtually impossible” to accurately predict when a second wave of swine flu will arrive.
A surge in the number of cases is widely expected in the autumn, when people’s immune systems are naturally weaker and schools and universities return after the summer holidays, but Sir Liam described this as only a “best guess”.
He said he hoped the current pandemic would follow the pattern of that in 1968-70, when the second wave hit at Christmas. This would give the government time to vaccinate as many people as possible.
A few weeks ago, one in four people reporting flu-like symptoms to their GP or the National Pandemic Flu Service were eventually diagnosed with swine flu; now it is one in 10.
“It is unusual to have [flu] around this time of year even at the levels we have got,” Sir Liam said. “We do expect a second wave but we can’t forecast when. The best guess is it will be this winter.”
The Health Protection Agency said that most cases of the H1N1 virus were mild, and that there was no sign of the virus mutating, becoming more severe or developing resistance to anti-viral drugs.
David Salisbury, Director of Immunisation, said: "This study is an interesting insight into the impacts of different strategies for seasonal influenza vaccination when large quantities of vaccine can be given before transmission of influenza takes place. However, we are presently in very different circumstances when there has already been much transmission of H1N1 infection amongst children. Hence, we believe that vaccination should start with individuals with risk factors for influenza (as in priority list) as they will benefit most from the early supplies of vaccine. We will review carefully subsequent uses of H1N1 vaccine either for individual protection or to reduce transmission."