Herpes simplex type 1 versus Herpes simplex type 2 in anogenital herpes; a 10 year study from the Waikato region of New Zealand.
OBJECTIVE
To determine the proportion of Herpes simplex type 1 vs Herpes simplex type 2, as a cause of anogenital herpes in the Waikato region. We specifically looked for changes in the proportions over time, and for gender or age group associations.


METHODS
We undertook a retrospective data-analysis of all anogenital isolates positive for Herpes simplex types 1 or 2 in those greater than and equal to 14 years of age, received at Waikato Hospital Laboratory (Hamilton, New Zealand) over a 10-year period. Around half way through the study period, the test type changed from viral culture to HSV nucleic acid amplification assay.


RESULTS
Between 1997 and 2006, 3933 anogenital isolates were positive for either Herpes simplex types 1 or 2. The proportion of type 1 vs type 2 oscillated around 30 to 40% over the 10 years, with no particular trend. Overall, 71% of positive isolates were from females, with 80% of the type 1 isolates from females. Presence of type 1 was inversely proportional to age, accounting for 53% of positive isolates in the <25 year age group, 30% in the 25-35 year group, and 26% in the >35 year group.


CONCLUSIONS
Herpes simplex type 1 is a major contributor to anogenital herpes in the Waikato. Females accounted for the majority of both types and there was a much higher proportion of type 1 seen in the younger age groups. These findings have been reported overseas but this is the first reported New Zealand data.
Gray
Erana
E
Sexual Health Clinic, Waikato Hospital, Private Bag 3200, Hamilton, New Zealand. erana_gray@hotmail.com
Morgan
Jane
J
Lindeman
Jennifer
J
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D005260:Female; D006558:Herpes Genitalis / Q000145:classification* / Q000453:epidemiology; D018259:Herpesvirus 1, Human / Q000302:isolation & purification* / Q000472:pathogenicity; D018258:Herpesvirus 2, Human / Q000302:isolation & purification* / Q000472:pathogenicity; D006801:Humans; D008297:Male; D008499:Medical Records; D008875:Middle Aged; D009520:New Zealand / Q000453:epidemiology; D012189:Retrospective Studies; D017678:Sex Distribution