The UKHealthProtectionAgency estimates that around a quarter of the population could be affected by avian flu in the future, with possibly 50, 000 deaths in England and Wales alone.
The HealthProtectionAgency (HPA) said its figures suggested about 100, 000 people in the UK were currently living with HIV, but about a quarter of them did not know they had the virus, which untreated can lead to the development of Aids.