The risk of HIV transmission by oral sex and kissing is very low. While infectious HIV may be detected in the saliva, it is present in substantially reduced quantities compared with blood or genital secretions. Furthermore, the saliva contains endogenous antiviral factors, including HIV-speciﬁc antibodies, and a number of soluble factors, such as secretory leukocyte protease inhibitor. Saliva may alter HIV-1 gp120 structure and lyse HIV-infected cells secondary to the inherent hypotonicity of the saliva. While oral sex has been identiﬁed as the only reported risk factor for HIV transmission in some men who have sex with men, the findings of large cohort studies in which no cases of HIV transmission were identiﬁed have not confirmed this. However, oral transmission of SIV has been reported in a macaque model. There is no evidence that HIV transmission can occur as a result of exposure to tears, sweat, faeces or urine.