Over half of UK swine flu hospital admissions and inpatient deaths occurred in people with no underlying health problems or obvious risk factors, new research at the University of Liverpool has shown.
"The study found that well over half of hospital admissions and deaths occurred in previously healthy people. Hospital admissions were highest in children under the age of five years and pregnant women.
The findings support the vaccination of pregnant women - which may also protect their soon-to-be-born children - and all children under five years of age," Dr Calum Semple, Senior Lecturer in Child Health at the University of Liverpool and Consultant Respiratory Paediatrician at Alder Hey Children's Hospital, said.
The research, carried out by the Universities of Liverpool and Nottingham, was based on an analysis of clinical data from 55 hospitals in 20 urban areas during the first wave of the swine flu pandemic during May to September 2009. The data were collected as part of the Government's Influenza Clinical Information Network (FLU CIN) surveillance programme.
Between April 27 and September 30 2009, data were collected on 631 people with swine flu - 405 of them adults - admitted to the 55 hospitals. Their ages ranged from three months to 90 years.
One in three (36 percent) were under 16 and one in 20 (5 percent) were aged 65 and older. Those from black and minority ethnic backgrounds made up over 60 percent of admissions.
Just under half of the patients had underlying conditions - mostly asthma. But almost half of them were not routinely using inhalers or taking oral steroids, which suggests they had mild, rather than severe, disease. Over half of all admissions (55 percent) and inpatient deaths (59 percent) occurred in people with no previous health problems.