Corey et al. Since the absolute reduction was not large, the yearly number needed to treat was Individuals in the valacyclovir group received mg of valacyclovir once daily for eight months. This therapy effectively reduced viral shedding relative to the placebo group. As a result, it reduces transmission when the source partner does not have any recognizable symptoms but is still shedding virus, which is when most transmission events occur 18 , The potential benefits of using suppressive valacyclovir to reduce transmissions are obvious: reducing the psychological and physical harms of acquiring genital herpes, while lowering the economic costs associated with this infection.
Psychologically, acquiring symptomatic genital herpes can have a significant emotional impact on patients 20 — Such patients may suffer from social isolation and have difficulty initiating relationships 23 , In contrast, other studies have shown that appropriate counseling can significantly reduce the psychological harm caused by diagnosing genital herpes 25 — Receiving genital herpes can also cause anger towards the source partner.
Additionally, the source partner may be significantly worried about transmitting genital herpes to their non-infected partner Therefore by reducing transmission, valacyclovir can diminish possible psychological harms, although counseling has been shown to be effective in this regard as well Potential physical harms due to genital herpes can be prevented with suppressive therapy, assuming that the partner acquires a recognizable, symptomatic infection.
Genital herpes caused by HSV-1 recurs infrequently and the frequency decreases over time with a recurrence duration of 7 days 12 , In contrast, HSV-2 genital herpes recurs more frequently and the rate of recurrence decreases slowly over time with a recurrence duration of 8. Local symptoms for HSV-2 infection include pain, itching, and vaginal or urethral discharge Complications of genital herpes include dysuria, aseptic meningitis, autonomic nervous system dysfunction, transverse myelitis, yeast infections, and extragenital lesions Economically, reducing the population incidence of genital herpes will decrease such healthcare costs as hospitalizations, clinical examinations, consultations, and tests.
Indirect economic costs for patients, such as time off work and traveling costs, will also be avoided 21 , 23 , 31 , Recurrent genital herpes can also lower work effectiveness during severe symptomatic events Szucs et al. Of the total cost, In summary, reducing transmission will diminish the psychological, physical, and certain economic burdens of symptomatic genital herpes.
However, it should be noted that only There are numerous costs associated with suppressive valacyclovir therapy in couples discordant for genital herpes. First, patients may replace safe sex practices with such therapy. Condoms offer significant, but not complete, protection against HSV-2 33 , Condoms also protect against other sexually transmitted infections that an individual in the relationship may have.
However, Corey et al. Furthermore, it may be suggested that suppressive use of valacyclovir will cause antiviral resistance. Despite a lack of long-term studies, no resistance to this drug has been found for therapy lasting one year 35 — Currently, there appears to be little physical harm in taking valacyclovir every day for more than a year in healthy patients 35 — In patients infected with human immunodeficiency virus HIV , there are no data on the safety of therapy lasting more than 6 months Headaches, nausea and vomiting, dizziness, and abdominal pain are the most commonly reported adverse effects.
Psychologically, taking a drug every day may cause harm or distress. Although patients with recurrent genital herpes prefer suppressive over episodic therapy 22 , it is not known how asymptomatic patients would respond to and comply with daily therapy over the long-term. As previously described, there would be some financial savings with suppressive valacyclovir therapy, but there would also be significant economic costs associated with this program due to drug costs and screening 31 , 32 , Another significant cost would be identifying those individuals that have an asymptomatic or unrecognized clinical infection.
However all three groups have similar frequencies of asymptomatic shedding events 19 , defined as detection of HSV on the surface of skin or mucosa in the absence of genital lesions Most individuals with unrecognized symptomatic genital herpes can identify their symptoms with counseling and education 42 , The presence of antibodies to HSV-1 alone gives no information on the presence of genital herpes because the site of the infection, oral or genital, cannot be determined Since HSV-1 is very common, genital herpes due to HSV-1 would be difficult to detect without swabbing genital lesions.
In addition, the frequency of testing required to identify individuals with genital herpes adds to the cost of screening If testing were recommended with every new sexual partner, there would be considerable strain placed on the healthcare system and the patient. Moreover, it is predicted that there would be significant psychological harm associated with diagnosing patients with genital herpes who were previously unaware of their infection.
Through a large screening program, physicians may actually cause more psychosocial harm to asymptomatic individuals, such as social isolation and reluctance to initiate relationships, than the physical harms these individuals experience 23 , 24 , 46 , However as previously noted, studies have shown that counseling is effective in reducing psychological harm upon diagnosis 25 , In addition, disclosing the problem to their current partner, who may raise questions of infidelity or past sexual history, may damage or ruin the relationship.
Screening of targeted populations, however, may be appropriate. Such circumstances may include individuals who are at increased risk of HIV infections, HIV positive patients, and patients with a partner with genital herpes By diagnosing these individuals with genital herpes, infected individuals may recognize outbreaks and abstain during such periods.
In fact, transmission rates may decrease after source partners disclose Current models suggest that suppressive therapy will have a minimal effect on reducing the population incidence of genital herpes at the currently low levels of diagnosis and treatment The coverage level and the duration of suppressive therapy are important factors in reducing the population incidence The coverage level is primarily determined by the proportion of patients diagnosed and the proportion of diagnosed that are receiving therapy.
With a coverage level of 3. According to Williams et al. Additionally, the duration of suppressive therapy can be increased. At a coverage level of 3. Therefore, the savings from the program would balance the cost after 92 years. Obviously, one must also consider the increased quality of life gained from a decrease in incidence. Such screening would be essential to this program because they are the majority of individuals with genital herpes and the main group transmitting the virus 42 , The compliance may also be lower in the general public than in the trial performed by Corey et al.
The potential for overuse of expensive serologic testing is enormous. The psychological and physical benefits noted above may convince a symptomatic, discordant couple into asking for valacyclovir to reduce the likelihood of transmission, but in how many instances will valacyclovir reduce transmission? Thus, transmission is a rare event without valacyclovir use.
Furthermore, when transmission does occur, most people do not develop symptomatic genital herpes. This approval gives patients another tool, in addition to safer sex practices, to help them protect their partners," said Larry Corey, MD, lead study investigator and professor, Laboratory Medicine and Medicine, University of Washington and head of the Program in Infectious Diseases, Fred Hutchinson Cancer Research Center.
While genital herpes is not a life-threatening disease, once infected, the virus never leaves the body, making it a lifelong condition that can recur at various times with or without symptoms. The virus is generally spread through skin-to-skin contact during sexual activity and often during times when there are no visible signs of a herpes outbreak.
In fact, in clinical studies, the majority of people got GH from a partner who knew they had GH but reported no signs or symptoms at the time of recent sexual activity. The approval follows a unanimous recommendation by an FDA Advisory Committee on May 14, , to approve suppressive therapy with Valtrex for reducing the risk of transmission of genital herpes in otherwise healthy, heterosexual individuals. GlaxoSmithKline acknowledges the patients and investigators who diligently participated in this very demanding and unique study.
We are very pleased by this approval and what this additional benefit can mean to millions of herpes sufferers and their partners," said Clarence L. Oct 1, Issue. Am Fam Physician. Read the full article. Get immediate access, anytime, anywhere. Choose a single article, issue, or full-access subscription. Earn up to 6 CME credits per issue.
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Email Alerts Don't miss a single issue. Sign up for the free AFP email table of contents. Susceptible partners were evaluated monthly for a total of eight months for signs and symptoms of HSV-2 infection and for HSV-2 antibody in the blood. Source partners those with herpes at the outset of the study were examined monthly for disease recurrence. Both partners were counseled on safer-sex practices and offered condoms at each visit. At the end of the eight-month study period, genital herpes had occurred in 41 of the sexual partners of those on placebo versus 21 who took valacyclovir, as judged by the antibody-blood test.
Couples who used condoms and valacyclovir had the lowest transmission rate. Food and Drug Administration for use in preventing genital herpes in couples in which one partner has genital herpes. The effectiveness of antivirals at reducing genital herpes transmission could also help to stem the AIDS epidemic, which affects 42 million people around the world.
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