The Mayor of London Boris Johnson said: "London is home to almost half of all people living with HIV in the UK, but a quarter of them are unaware they carry the virus.
"It is vital that people who might be at risk get tested, not only to reduce the risk of transmission to others, but to ensure they get the life-saving treatments that are available."
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Teenage twin brothers were found guilty today of murdering a 'quiet, humble' father who dared to intervene in a robbery in north London.
The women were reportedly both students at City and Islington College campus in Holloway Road.