More commonly though, it is men who rape or sexually assault other men or boys.
According to police figures, about one in five adult males are the victims in reported sexual offences. The real figure could be much higher as a man is much less likely than a woman to report a sexual violation.
Victims suffer alone and in silence mostly, because of shame and the fear they will not be believed and their sexuality will be questioned.
Support services are largely unavailable, which is why the South African Male Survivors of Sexual Abuse (Samsosa) organisation was formed recently.
Its founder is Rees Mann, a dynamic Johannesburg businessman who was himself a victim of sexual abuse. He hopes to bust various myths about male sexual abuse and stresses that it is never the fault of the victim.
No one should ever blame himself, as the only way it occurs is if there is a sexual criminal present, who is the sole guilty party.
The headline cases usually feature priests or teachers abusing their positions of authority. But it is much wider than this and the reality needs to be exposed.
People from all walks of life can be victims of sexual assault. It is an act of violence, not sexual gratification or orientation.
The motivation is to hurt, humiliate, destroy and cause pain, insecurity and hopelessness in the victim. Most convicted rapists and abusers of males describe themselves as heterosexual, not gay. They also say that it never mattered whether their victims were male or female.
More males than females are raped by strangers – 48% in one survey compared to 28% of females.
Mann aims to break the terrible silence on this issue and to help victims on their journey to healing. The first step is disclosure, which is best done to a trusted friend or a trained therapist.
Rees told me of a man in his 60s who wrote to him, disclosing for the first time the abuse he had suffered as a child.
Speaking to other victims also helps, which is best arranged through an organisation like Samsosa.
They can be contacted at www.samsosa.org or on 071-280-9918.
A small minority of those who have been abused can become abusers themselves, harming both male and female victims.
This is one more reason why we need to confront this problem with urgency. We are approaching the organisers of the 16 Days of Activism for No Violence against Women and Children campaign.
There should also be at least one day that focuses attention on male victims of sexual abuse.
They need to know that they are not alone and that they can be survivors and thrivers.
Jack Bloom is the Democratic Alliance leader in the Gauteng Legislature