Your article on herpes implies that it is only American physicians and pharmaceuticals companies who are concerned about the public health implications of an increase in genital herpes simplex virus (HSV) infection

(This Week, 12 December 1998, p 24)

. In contrast, many clinicians and public health specialists are concerned, but opinions are divided about what action will be cost-effective in countering this trend.

The key observation, briefly quoted in the article, is that genital ulceration promotes the transmission of HIV. Genital HSV infection has emerged as the most common cause of genital ulceration in the developed and developing worlds, with a reduction in bacterial causes.

The value of serological testing to improve diagnosis for genital HSV infection is that it will enable patients to be counselled, and receive antiviral therapy if appropriate. Furthermore, as part of the development of effective vaccines to prevent HSV infection, a serology test will …

Further to Michael Day’s excellent article on herpes simplex

(This Week, 12 December, p 24)

, indeed there has been a steady increase in genital herpes simplex in the US. However, the pattern has not been repeated in Britain.

New cases recorded by genitourinary clinics in Britain have remained static for around three years at around 15 000 per annum and as far as we know, new cases seen at GPs’ surgeries remain at about 2.4 patients per GP per year, making up a total of around 90 000. Interestingly, an increasing proportion of genital infection is caused by type 1 virus, traditionally associated with facial symptoms.

The reason for the difference between the American and British experience is that the acquisition of the type 1 virus in childhood is higher in Britain than in the US. The antibodies developed prevent later genital infection by type 1 virus and give partial protection against type 2.

The moral is clear. As with most infections, herpes simplex is best caught when you are young and your immune system is fresh. Symptoms are more likely to be mild or non-existent and you will be less likely to catch another strain of the virus on another site when you are older.

We would also ask you to correct what could be misunderstood in Day’s article. While we agree that there has been hype over the usually harmless herpes simplex virus, as a charity we are not allowed to campaign about it. We merely give advice and information about herpes viruses to patients, medical professionals and the public.