20,000 unaware they have HIV.
D015492:AIDS Serodiagnosis; D001364:Awareness; D015658:HIV Infections / Q000453:epidemiology* / Q000635:transmission; D006297:Health Services Accessibility; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D006113:United Kingdom / Q000453:epidemiology