what are 4 factors that help determine whether hiv is likely to be transmitted?
['Having Unprotected Sex. Most people get HIV by having sex. ... ', 'Drug Use. Using needles to inject drugs makes your chances of HIV higher. ... ', 'Having Certain Health Problems. Having a sexually transmitted infection (STI) makes your risk of HIV higher. ... ', 'Blood Products. ... ', 'Having Certain Jobs. ... ', 'References.']