Shiloh
Editor, Senior Moderator
Source: http://www.timesonline.co.uk/tol/tools_and_services/mobile_times/swine_flu/article6450267.ece
June 7, 2009
Expert: hospitals missing true extent of swine flu infection
Mark Henderson, Science Editor
The true extent of swine flu infection in Britain is being underestimated because hospitals are failing to test patients with respiratory illnesses for the virus, according to one of the world?s leading experts on the disease.
Professor Neil Ferguson, a senior epidemiologist at Imperial College, London, who advises the Government and the World Health Organisation, said an ?almost non-existent? hospital surveillance system means that serious cases of swine flu are almost certainly being missed.
Speaking at The Times Cheltenham Science Festival, he said there was anecdotal evidence of ?significant numbers? of cases of severe respiratory illness in London, which should be checked out in case they have been caused by swine flu. Wider surveillance strategies need to be rethought now that the H1N1 virus seems to be spreading widely through the community.
?One thing I am concerned about is that surveillance of severe disease is almost non-existent,? Professor Ferguson said. ?If you go into hospital and have severe respiratory disease, you will not be tested for H1N1.
?Anecdotally, I am hearing reports of a quite significant number of severe cases of respiratory illness in London. We need to be testing them.
?We need hospital-based surveillance, but while it?s being thought about it?s not been brought in yet.
?We?re not assessing respiratory patients for H1N1, and that is going to be important over the coming weeks.?
The UK needs to learn from the approach taken in the US where the epidemic is much more advanced, Professor Ferguson said.
?In the US, they?ve stopped trying to do individual case surveillance and they?re focusing on testing healthy young adults hospitalised with respiratory disease. That?s the direction we need to follow.?
While 541 cases have been officially confirmed, the true figure is several times higher and there is a danger that serious cases are not being picked up. At least a dozen people have been reported to have needed hospital treatment for H1N1, including a pregnant women who gave birth three months prematurely who remains critically ill, though the HPA could not provide confirmed statistics.
Professor Ferguson said that the HPA tally at best covers only half the total number of infections.
GPs identified six cases in May that were not linked to known infections, and extrapolations suggest that between 500 and 1,000 people with swine flu consulted a doctor last month but were not tested. As only a minority of patients with mild flu-like illnesses see a GP, even this is an underestimate, and two to three times as many people have probably had swine flu.
The HPA said it had already asked hospitals to test for swine flu. ?As part of the Agency?s enhanced surveillance all hospital labs in England have been asked by the HPA to refer specimens from all patients with flu-like illness to their HPA regional laboratory for testing,? a spokeswoman said.
She added that a pilot programme is being established at several hospitals to test patients who have other acute respiratory illnesses consistent with flu.
At present, swine flu surveillance has concentrated on tracing the contacts of people known to have the virus and testing them. Professor Ferguson said that while case-tracing had been valuable for monitoring the early phases of the outbreak, the spread of the disease means that that is becoming unsustainable. ?It will rapidly become impossible to track individual cases,? he said.Professor Ferguson said progress of the virus in the southern hemisphere would provide a good guide to how it is likely to spread in Britain in the autumn, as flu is highly seasonal.
The H1N1 virus, he said, is spreading much faster in the southern hemisphere, where it is winter, than in Europe and North America. In Chile, each patient is infecting about 1.7 other people, compared to about 1.2 in the UK, and a similar increase in transmission rates can be expected in the autumn.
?We?re getting some sense of what will happen from the southern hemisphere,? Professor Ferguson said.
June 7, 2009
Expert: hospitals missing true extent of swine flu infection
Mark Henderson, Science Editor
The true extent of swine flu infection in Britain is being underestimated because hospitals are failing to test patients with respiratory illnesses for the virus, according to one of the world?s leading experts on the disease.
Professor Neil Ferguson, a senior epidemiologist at Imperial College, London, who advises the Government and the World Health Organisation, said an ?almost non-existent? hospital surveillance system means that serious cases of swine flu are almost certainly being missed.
Speaking at The Times Cheltenham Science Festival, he said there was anecdotal evidence of ?significant numbers? of cases of severe respiratory illness in London, which should be checked out in case they have been caused by swine flu. Wider surveillance strategies need to be rethought now that the H1N1 virus seems to be spreading widely through the community.
?One thing I am concerned about is that surveillance of severe disease is almost non-existent,? Professor Ferguson said. ?If you go into hospital and have severe respiratory disease, you will not be tested for H1N1.
?Anecdotally, I am hearing reports of a quite significant number of severe cases of respiratory illness in London. We need to be testing them.
?We need hospital-based surveillance, but while it?s being thought about it?s not been brought in yet.
?We?re not assessing respiratory patients for H1N1, and that is going to be important over the coming weeks.?
The UK needs to learn from the approach taken in the US where the epidemic is much more advanced, Professor Ferguson said.
?In the US, they?ve stopped trying to do individual case surveillance and they?re focusing on testing healthy young adults hospitalised with respiratory disease. That?s the direction we need to follow.?
While 541 cases have been officially confirmed, the true figure is several times higher and there is a danger that serious cases are not being picked up. At least a dozen people have been reported to have needed hospital treatment for H1N1, including a pregnant women who gave birth three months prematurely who remains critically ill, though the HPA could not provide confirmed statistics.
Professor Ferguson said that the HPA tally at best covers only half the total number of infections.
GPs identified six cases in May that were not linked to known infections, and extrapolations suggest that between 500 and 1,000 people with swine flu consulted a doctor last month but were not tested. As only a minority of patients with mild flu-like illnesses see a GP, even this is an underestimate, and two to three times as many people have probably had swine flu.
The HPA said it had already asked hospitals to test for swine flu. ?As part of the Agency?s enhanced surveillance all hospital labs in England have been asked by the HPA to refer specimens from all patients with flu-like illness to their HPA regional laboratory for testing,? a spokeswoman said.
She added that a pilot programme is being established at several hospitals to test patients who have other acute respiratory illnesses consistent with flu.
At present, swine flu surveillance has concentrated on tracing the contacts of people known to have the virus and testing them. Professor Ferguson said that while case-tracing had been valuable for monitoring the early phases of the outbreak, the spread of the disease means that that is becoming unsustainable. ?It will rapidly become impossible to track individual cases,? he said.Professor Ferguson said progress of the virus in the southern hemisphere would provide a good guide to how it is likely to spread in Britain in the autumn, as flu is highly seasonal.
The H1N1 virus, he said, is spreading much faster in the southern hemisphere, where it is winter, than in Europe and North America. In Chile, each patient is infecting about 1.7 other people, compared to about 1.2 in the UK, and a similar increase in transmission rates can be expected in the autumn.
?We?re getting some sense of what will happen from the southern hemisphere,? Professor Ferguson said.
