Helena Bracken said revelations of events in the Austrian town of Amstetten, where Josef Fritzl imprisoned his daughter Elisabeth in an underground dungeon, had acted as a catalyst for people seeking help in Londonderry.
"We have had a lot more calls since the Fritzl case and when a young girl was raped in south Belfast last month. Things like this awaken people," she said.
Helena Bracken also claimed that Nexus and other counselling services in the city are only dealing with the tip of the iceberg.
There is a two year waiting list for appointments at the Clarendon Street based centre.
She said full-time counsellors at Nexus in Londonderry are dealing with a full capacity work load of 18-20 clients per week.
"This is the most horrendous thing to happen to anybody and it is a really uncomfortable thing for anybody to talk about. There is the old Irish cultural thing where we do not talk about sex and a lot of it was brushed under the carpet," said Helena.
However, the Nexus Regional Manager said high profile cases seemed to spark the national conscience and attitudes to pushing aside social constraints and taboos are changing.
As a result Helena Bracken believes that the eradication of sexual abuse in Londonderry, as well as the legacy of past cases is at least a generation away. The Regional Manager stated the breaking of a wall of silence and educating young people to speak out will be the only way forward.
"Sexual violence affects everything. Generally, people can't work, become depressed, lack in parenting skills and sometimes drink a lot. It is a ripple effect."
Funding restrictions mean that Nexus can only offer six month courses, equating to 24 hour-long sessions and Helena suggests this is inadequate to deal with the vast trauma of someone who has been abused daily over a lengthy period.
The Nexus leader also pointed out that there needs to be a greater realisation that the shame lies with the perpetrators of the crime and not the victim of abuse.
"I feel sometimes there is more press coverage given to the perpetrator than the victim. There are complaints that they are not enough tough sentences handed down, but the victims are always condemned to a life sentence."