Martin Jones, MSC, RN, CNS.
Co-ordinator, Sexual Health, Eastbourne Downs Primary Care TrustThis Factfile focuses on the most common viral sexually transmitted infections (STIs), genital wart virus infection and genital herpes. Blood-borne viral STIs are covered next month.
This Factfile focuses on the most common viral sexually transmitted infections (STIs), genital wart virus infection and genital herpes. Blood-borne viral STIs are covered next month.
Viral STIs are associated with long-term or even life-long carriage of infective agents.
Genital wart virus infection
Wart virus infection is the most common viral STI diagnosed in genitourinary medicine departments (GUM) in England, Wales and Northern Ireland. In 2001, diagnoses of genital warts increased by 2% (34 843 to 35 497) in males and by 3% (31 268 to 32 196) in females (PHLS, 2003). There has been a tripling of cases in males and a five-fold rise in females between 1972 and 2001.
Genital warts are caused by infection with human papilloma virus (HPV) types, which are spread through sexual contact. The development of molecular laboratory techniques has enabled scientists to identify a number of HPV types that are associated with genital wart virus infection and with cervical cancer. HPV types associated with cancer of the cervix do not tend to cause external anogenital warts. This has led to a revision of guidelines for managing genital wart virus infection. HPV typing is not routinely available outside research laboratories.
Diagnosis is made on clinical examination. Genital warts are benign fleshy growths in the anogenital region, often noticed by the patient. Men and women who have had anal sex may have peri-anal warts. Treatment is for cosmetic reasons, and may be carried out at home or in the clinic. Many patients experience psychological distress.
Genital warts may occur in stable sexual relationships. Diagnosis is not an indication that either partner has had a different sexual partner, as the incubation period may be 3-18 months or even longer (MSSVD, 2002).
For treatment options in the clinic or at home, see panel, right. Other surgical treatments are listed in Table 1, along with clearance rates. All treatment approaches are associated with recurrence, adding to the psychological burden of some people.
Advice to patients must be up to date and consistent. Outdated, conflicting advice adds to patient distress. Condoms are indicated for client preference and in new relationships.
There is a link between certain HPV types and cervical intra-epithelial neoplasia (CIN) or dyskariosis, which may cause anxiety to patients. The HPV types linked with cervical cancer are different from those causing external genital warts. Women do not require more frequent cervical smear tests - follow guidance from the NHS Cervical Screening Programme. Research is taking place to determine the most appropriate management strategy for women found to have HPV infection on a cervical smear test (NHS Cancer Screening Programmes, 2003).
Genital herpes is the most common cause of genital ulceration in the UK and is associated with an increased risk of transmission of HIV. In 2001, there were 17 850 new cases in England, Wales and Northern Ireland (PHLS, 2003).
Genital herpes is caused by infection with herpes simplex virus type 1 (HSV1) or herpes simplex virus type 2 (HSV2). HSV1 infection typically causes oral herpes (cold sores) and is increasingly the cause of genital herpes. HSV2 is almost exclusively found in genital areas.
Genital herpes may be caused by unprotected vaginal, oral or anal sex. Neonatal infection is rare but can be severe, so Caesarean section is advised for women experiencing a primary attack at labour.
Typically, primary genital herpes starts with a prodrome with itch or tingling, followed by localised erythema; blisters form and burst creating painful ulcers, which crust over before eventually healing; systemic 'flu-like' symptoms are not uncommon, including: fever, lymphadenopathy, aching limbs, headache and backache. Patients, particularly women, may experience dysuria and, in severe cases, women may develop urinary retention. Peri-anal lesions can cause pain when opening bowels.
Like genital warts, diagnosis is on clinical examination as this allows immediate antiviral treatment. However, swabs taken from freshly punctured blisters or newly formed ulcers should be sent in viral culture medium for HSV culture, which may include typing according to the local laboratory service. Swabs from crusted or healing ulcers are unlikely to provide sufficient viral material for successful culture.
After primary infection, HSV remains latent in local sensory ganglia but may reactivate to cause recurrent attacks or asymptomatic viral shedding. The greatest risk of passing HSV to a sexual partner is while symptoms are present. However, asymptomatic viral shedding, particularly - but not exclusively - during the first year after infection, can transmit infection to sexual partners.
Advice on future sexual precautions will vary. A condom may be useful, particularly during recurrences or in new relationships. Long-term partners may already have unrecognised or asymptomatic HSV infection.
Recurrences, except in individuals with HIV, are usually shorter and less painful than the primary attack and tend to be less common over time. If recurrences are frequent, for example six or more a year, suppressive antiviral therapy for up to a year may help, via a local GUM clinic (CEG, 2002b).
People with genital herpes often experience extreme anxiety and distress. They should be given written information to support advice or discussion, time to ask questions, and the opportunity to return.
Indications for seeing the sexual partners of people diagnosed with genital herpes include: diagnosis of unrecognised HSV infection, answering questions, providing health information and managing distress.
A history of genital herpes and/or short recurrences is unlikely to affect the outcome of a pregnancy. Pregnant women with a past history of genital herpes and their partners should be managed sensitively. However, a primary attack, particularly towards the end of the third trimester, can cause severe, potentially life-threatening neonatal illness. All obstetric units should have policies in place for this rare situation.
TREATING GENITAL WART VIRUS INFECTION
- Cryotherapy involves freezing individual warts, for example with liquid nitrogen. Nurses working with patient group directions (PGDs) may perform this weekly. It is useful for small numbers of warts and keratinised warts. However, cryotherapy requires weekly clinic visits until the warts are no longer visible, and may be inconvenient to patients
- Ablative treatment with trichloroacetic acid (TCAA) may similarly be performed by nurses working with PGDs. TCAA is applied using a wooden 'orange stick', taking care not to allow acid onto surrounding skin. TCAA is caustic and the patient must be advised that it may cause depigmentation of treated areas.
- Podophyllotoxin is available in a cream or solution, with applicators and a mirror, if necessary, for home treatment. Podophyllotoxin is useful, particularly for large numbers of soft, non-keratinised warts. It should not be used in pregnancy. Podophyllotoxin has several advantages over unpurified podophyllin, including better tolerability, better efficacy and patient convenience. Many GUM clinics no longer use unpurified podophyllin because of concerns about toxicity. Podophyllotoxin should be avoided in pregnancy and stopped if it causes unacceptable levels of irritation
- Imiquomod is available as a cream for home treatment. It acts by stimulating local immune responses to wart virus infection. Imiquomod costs £55.18 per treatment pack, compared with £14.49-£16.62 for podophyllotoxin (BMA/RPSGB, 2002), so may often be seen as a second-line treatment, after other, cheaper options have failed. When clinic costs are added in, home treatments may be cheaper.
TREATMENT OPTIONS FOR HERPES VIRUS
- Treatment is useful only when started within five days of the start of the attack or if new lesions are forming
- There is no clinical advantage between the three licensed antiviral drugs, so aciclovir is preferred on grounds of cost (BMA/RPSGB, 2002). Treatment with topical aciclovir cream is not indicated as it has no effect on the clinical outcome of genital herpes
- Pain and flu-like symptoms may be managed with paracetamol or aspirin
- Lignocaine gel is useful as a topical analgesic
- Laxatives may help in peri-anal HSV.
COST OF ANTIVIRAL DRUGS
- Aciclovir 200mg 5 x daily, £4.23- Famciclovir 250mg 3 x daily, £28.12
- Valaciclovir 500mg 2 x daily, £23.50
- Next month's Factfile looks at bloodborne STIs
British Medical Association and Royal Pharmaceutical Society of Great Britain. (2002)British National Formulary 44. London: BMA/RPSGB.
Clinical Effectiveness Group (AGUM & MSSVD). (2002a)National Guideline for the Management of Anogenital Warts. www.agum.org.uk
Clinical Effectiveness Group (AGUM & MSSVD). (2002b)National Guideline for the Management of Genital Herpes. www.agum.org.uk
Medical Society for the Study of Venereal Diseases. (2002)Sexually Transmitted Infections Foundation Course: course manual 2002-2003 version 1. London: MSSVD.
NHS Cancer Screening Programmes. (2003)Available at: www.cancerscreening.nhs.uk
Public Health Laboratory Service. (2003)HIV and Sexually Transmitted Infections. www.phls.org.uk