There has been a dramatic rise in people presenting with hepatitis B at sexually transmitted infection (STI) clinics.
Data published yesterday show the number of cases detected during clinic screening in 2003 represented a 96.5 per cent increase on 2002.
Some 57 cases were reported in 2002 and 112 in 2003, the latest year for which data are available.
The Health Protection Surveillance Centre or HPSC (formerly the National Disease Surveillance Centre) said the rise could be due to a rise in people attending STI clinics from areas of the world such as Sub-Saharan Africa, Asia and parts of eastern and central Europe where hepatitis B is endemic.
"Between 1989 and 1999 infectious hepatitis B cases reported through the STI quarterly notification system ranged from 0 to 4 cases per year. Notifications increased from two cases in 1999 to 57 in 2002 and 112 cases in 2003. This is the highest yearly total on record," the HPSC said.
Dr Mary Cronin, a specialist in public health medicine with the HPSC, said the public should not be alarmed by the rise but the situation needed to be monitored very closely.
She said hepatitis B, which in some cases may lead to liver cancer, can be transmitted sexually, through blood or from mother to child in the womb. Healthcare workers and the families of infected persons could be vaccinated against it, she added.
Meanwhile, the HPSC's STI report for 2003 shows more than 11,000 sexually transmitted infections were reported, an overall rise of 6.5 per cent on 2002 data.
More than 1,200 of the infections were among the 0-19 age group, but most - over 6,800 - occurred in the 20-29 age group. "This age group is more likely to have higher numbers of sexual partners, change partners more frequently and engage in high-risk behaviour such as unprotected sex with new sex partners," the report said.
Most cases were reported in the eastern region.
The most commonly reported STIs in 2003 were ano-genital warts, non-specific urethritis and chlamydia trachomatis.
In women if chlamydia is not treated it can cause pelvic inflammatory disease which can lead to ectopic pregnancy, chronic pelvic pain and infertility. Some 70 per cent of women and 50 per cent of men with this infection show no symptoms.
A subcommittee within the HPSC is examining the need for chlamydia screening in Ireland.