Genital Herpes | Questions & Answers | 2010 Treatment Guidelines
Question 1: What is the recommended technique to obtain a specimen for herpes simplex virus (HSV) culture?
Answer: Cell culture and polymerase chain reaction (PCR) are the preferred HSV tests for persons with genital ulcers or other mucocutaneous lesions. Sensitivity of culture is low, especially for recurrent and healing lesions. Cultures, therefore, should be obtained from vesicular lesions if possible, but otherwise from early-stage lesions for best sensitivity. PCR assays for HSV deoxyribonucleic acid (DNA) are much more sensitive, increasingly being used, and are the test of choice for HSV infection in the central nervous system.
Question 2: What are the treatment criteria and dosage recommendations for the use of imiquimiod for herpes? Is the treatment painful?
Answer: Imiquimod has been used as a topical alternative for episodic treatment of lesions thought to be acyclovir-resistant or nonresponsive in HIV-infected individuals. The drug has no direct antiviral activity, and its effect might be mediated through activation of monocytes/macrophages to secrete various cytokines. The 2010 STD Treatment Guidelines mention that it is applied as a topical 5% cream once daily for five consecutive days. Local inflammatory reactions, including redness, irritation, induration, ulceration/erosions, and vesicles, are common with the use of imiquimod.
Question 3: Why is immunoglobulin M (IgM) not helpful for diagnosis of herpes?
Answer: Sensitivity of current IgM assays is too low to be used; these tests are not type-specific and they might be positive during recurrent episodes of herpes. In addition, false positive test results are relatively common with currently available IgM tests for herpes. Therefore, current assays are not helpful and should not be used.
Question 4: For genital HSV, does culture have a role in screening?
Answer: Culture is not useful for screening. Failure to detect herpes simplex virus (HSV) by culture or polymerase chain reaction (PCR) does not indicate an absence of HSV infection, because viral shedding is intermittent.
Question 5: Is routine herpes simplex virus (HSV) screening recommended using immunoglobulin G (IgG) type-specific serology?
Answer: According to 2010 STD Treatment Guidelines, type-specific HSV serologic assays might be useful in the following scenarios: 1) recurrent genital symptoms or atypical symptoms with negative HSV cultures; 2) a clinical diagnosis of genital herpes without lab confirmation; 3) a partner with genital herpes. Screening is not recommended for the general population. You may consider it if the person presents for STD evaluation as part of the routine screening, in persons with HIV infection, and with men who have sex with men (MSM) at increased risk for HIV acquisition.
Question 6: What is your recommendation for treatment of recurrent genital herpes simplex virus 1 (HSV 1)?
Answer: Recommendation for the treatment of recurrent genital HSV 1 is the same as for recurrent genital HSV-2. Both episodic and suppressive therapy recommendations can be found on page 22 of the 2010 STD Treatment Guidelines.
Question 7: How do you identify recurrence of herpes simplex virus (HSV) versus drug resistance, when recurrence is part of the disease process?
Answer: Clinically significant drug resistance is typically manifest as a failure to respond to therapy with thymidine kinase inhibitors, such as acyclovir. Cultures from active lesions can be sent with requests for acyclovir sensitivity testing. This is particularly important in immunocompromised individuals. In immunocompetent individuals, patient drug resistance is relatively rare.
Question 8: There was no mention of immunoglobulin G (IgG) use in diagnosis and management of genital herpes simplex virus (HSV). Is this still useful, or has it gone the way of immunoglobulin M (IgM)?
Answer: IgG tests are recommended in the diagnosis of HSV infections, but only type-specific HSV serologic IgG assays based on HSV glycoprotein G2 and glycoprotein G1 are accurate. Recommendations appear on pages 20 and 21 of the 2010 STD Treatment Guidelines.
Question 9: When should young adults presenting for sexually transmitted infection (STI) screening be offered herpes simplex virus (HSV) immunoglobulin G (IgG) testing?
Answer: According to the 2010 STD Treatment Guidelines, type-specific HSV serologic assays might be useful in the following scenarios: 1) recurrent genital symptoms or atypical symptoms with negative HSV cultures; 2) a clinical diagnosis of genital herpes without lab confirmation; 3) a partner with genital herpes. Screening is not recommended for the general population. HSV screening may be considered as part of routine screening, if the person presents for STD evaluation in persons with HIV infection, and with men who have sex with men (MSM) as increased risk for HIV acquisition.
Question 10: Any guidance on how long to prophylaxis a discordant couple where one individual has herpes?
Answer: There is no specific guidance on how long to prophylax a discordant couple when the infected person is taking daily valacyclovir, however, yearly testing of the uninfected partner may be helpful. If the uninfected partner has seroconverted to HSV, then prophylaxis can be stopped. If no seroconversion occurs, prophylaxis can continue.
Question 11: What are the current acyclovir dosing recommendations for herpes simplex virus (HSV), both episodic and prophylactic?
Answer: For episodic treatment of HSV CDC recommends acyclovir 400 mg. orally three times daily for five days, or acyclovir 800 mg. orally twice daily for five days, or acyclovir 800 mg. orally three times daily for two days. For prophylactic treatment the recommendation is acyclovir 400 mg. orally twice a day.
Question 12: Is it recommended to give suppressive therapy for asymptomatic HSV?
Answer: Suppressive antiviral therapy is likely to reduce transmission when used by persons who are HSV-2 seropositive without a history of genital herpes (2010 STD Treatment Guidelines, page 22).