Background/introduction Most populations have observed an increase in the role of HSV-1 as a cause of genital herpes simplex virus (HSV)

Aims To analyse HSV serotypes in first episode genital herpes in North West Northern Ireland.

Methods All patients who tested positive for HSV and were coded as C10A from 01/03/2015 – 01/03/2016 were included. Demographic details including sex, age, ethnicity and sexual identity were recorded. The confirmed serotype (HSV-1 vs HSV-2) was noted.

Results A total of 36 cases of first episode genital HSV was seen. 100% were white Caucasian (35/36 White UK); 29 were female and 7 were male. All females self-reported as heterosexual and of the 2/7 men were MSM. Overall median age at diagnosis was 23 years old (range 16–40). Of the 36 positive PCR tests 83.3% (30) were HSV-1 and 6.7% (6) were HSV-2. The median age at diagnosis for HSV-1 was also 23 years (range 16–32); 26 were female and 4 male. Of the 6 positive who tested positive for HSV-2, 3 each were male and female.

Conclusion It is well documented that HSV-1 is increasingly prevalent as a cause of first episode genital HSV, our rate of 83% for HSV-1 infection is notably high. Although not a significant diagnostic or management challenge this may reflect a lower prevalence of HSV-2 infection within the local sexually-active population or an increasing level of sexual risk behaviour capable of transmitting HSV-1 infection. Local clinicians need to be aware of the differences in prognosis for HSV-1 infection such that accurate information and advice can be given to help reduce stigma traditionally attached to HSV-2 infection.