The number of people in Northern Ireland diagnosed annually with HIV could double this year, shock figures revealed today.

As many people were diagnosed in the first six months of the year as in the whole of 2006.

Chief Medical Officer Dr Michael McBride said be was very concerned by a "worrying surge" in the number of new cases.

Speaking on World Aids Day, Dr McBride said: "It is vital that people look after their sexual health."

His warning was issued as the Communicable Diseases Surveillance Centre for Northern Ireland (CDSCNI) issued its annual report on the surveillance of HIV and other sexually transmitted diseases.

It showed that during 2007 there were 65 new diagnoses of HIV, an increase of 16% on the 56 cases in 2006.

Worryingly provisional figures for the first six months of this year showed the prospect of an even bigger increase this year - with 54 new cases diagnosed by the end of June.

"If this trend is maintained, Northern Ireland will have witnessed a potential near doubling of cases by the year end," it warned.

The number of people diagnosed each year has shown a continuous increase over the past 10 years.

Dr Neil Irvine, consultant epidemiologist with CDSCNI, said the latest report again confirmed the upward trend. He said it showed no sign of abating despite consistent messages about the need for safe sex.

The report also showed that in the 25 years since the emergence of HIV as a major threat to public health, 593 people have been diagnosed in Northern Ireland.

The Chief Medical Officer said: "In Northern Ireland the incidence of HIV is relatively low in comparison with the rest of the UK - however we cannot be complacent."

He added: "The latest figures for Northern Ireland indicate a worrying surge in new diagnoses of HIV.

"I am also very concerned by provisional figures for the first half of 2008 which would indicate further substantial increases in the numbers this year."

Dr McBride insisted: "It is vital that people look after their sexual health. As Chief Medical Officer I will continue to advocate for the prevention of HIV and other sexually transmitted infections in the context of an overall approach to good sexual health."

The Department of Health's Sexual Health Promotion Strategy and Action Plan was launched today.

Dr McBride said it aimed to improve, protect and promote the sexual health and wellbeing of the population of the province. One of its primary aims was to reduce the number of STIs, including HIV.

"World Aids Day presents an opportunity to increase awareness of HIV and AIDS and the ongoing efforts in prevention, treatment and care.

"The fact that HIV infections are continuing to occur demonstrates the need to continue to reinforce the 'safer sex' message," he said.

He added: "I am committed to ensuring we redouble our efforts and early diagnosis and that people in Northern Ireland living with HIV have access to the highest standards of treatment and care and most effective use of drug treatment."

The vice-chair of the Stormont Assembly's Health Committee, Michele O'Neil, called on the Executive and Assembly to play their part in increasing awareness and assisting those suffering from HIV/Aids.

Ms O'Neil said: "It is now our responsibility in the assembly to raise awareness of issues such as this and to have an open and frank discussion."

The Sinn Fein MLA added: "This is an issue of both local and global significance, one which Ireland is not immune from, and which requires united action.

"There is also a continued need for greater awareness of sexual health and safe sex practices."

She said political leaders needed to recognise the relationship between poverty, discrimination and HIV/Aids, and the need to break the cycle of underdevelopment, poverty and disease.

"The assembly has a responsibility to address this growing crisis," said Ms O'Neil.