Infectious Disease Compendium

Herpes simplex 1 and 2

Microbiology

A herpes virus.

Epidemiologic Risks

Sex. But any mucocutaneous contract can lead to herpes anywhere on the body. I had a patient with HSV outbreaks between the shoulder blades and another with lesions on the leg. Hmmmmmm.

As you plan that trip, remember that for the prevention of spread, condoms are only about 30% (PubMed).

About 1 in 5 Americans are seropositive for HSV2 and only 10% have had a symptomatic infection. And they shed low levels of virus all the time. Most HSV2 is therefore passed on by people who do not know they have Herpes to those who do not know they got it. Condoms anyone?

Syndromes

Painful, shallow (usually genital is 2, mouth 1) ulcers where ever there was contact. With primary disease patients can be systemically ill and, if female, may be viremic (PubMed).

Whitlow on the finger (don't put that finger in your eye).

Herpes Gladiatorum: skin disease in wrestler's and other close contact sports, a fatal form has been reported in Sumo wrestlers.

Cold sores can recur for a variety of reasons, although some people are genetically predisposed (PubMed) and have the C21orf91 genotype. As the Bard said, "The fault, dear Brutus, is not in our stars, But in ourselves."

Keratitis

Encephalitis: type 1 more often than type 2 in adults, type 2 more often than type 1 in neonates. May present with a Bell's palsy. Patients on TNF-alpha inhibitors (part of the infectious disease employment act) may have an increased predilection for HSV encephalitis. There are many diseases that can mimic HSV encephalitis (PubMed). 20% can have the initial PCR negative, repeat in a few days if suspicious. HSV should be isolated to one temporal lobe. If both or other parts of the brain, there may be another diagnosis (PubMed).

Aseptic meningitis (often with acute genital disease).

Pneumonia: can occur in patients on long term ventilators and can be associated with a clinical decline (PubMed).

Treatment

Genital Ulcers: acyclovir, famciclovir (125 po bid x 5d (PubMed) or famciclovir 1500 mg once or 750 mg twice a day for 1 day at onset of symptoms (PubMed)), valacyclovir po is effective in treating acute outbreaks and preventing recurrence.

Encephalitis: 21 days IV, dont use po.  And long term po adds nothing (PubMed).

No matter what you give, the patient will still intermittently shed HSV (PubMed).

500 mg po qd of valacyclovir is highly successful at preventing spread of HSV2 from a positive to a negative partner, but a condom is still a good idea (PubMed).Valacyclovir may be better at preventing viral shedding (PubMed). Daily suppression (500 mg valacyclovir qd) has better results than treating outbreaks (PubMed). Even in patients with first case, valacyclovir is successful in preventing reoccurrences (PubMed).

Treating HSV in HIV positive females who are not yet on HAART markedly decreases vaginal HIV (thereby lowering infectiousness) and lowers the blood HIV viral load by 0.5 log (PubMed) and will slow the rate immunologic decline.

Herpes Gladiatorum: If > 18 y/o famciclovir 250mg TID X 10days for initial outbreak; 5 days for recurrence valacyclovir 1g BID X 10 days initial outbreak; 5 days for recurrence. If < 18 y/o acyclovir 40-80mg/kg/d divided 3-4 times a day for 7-10 days.

Prophylaxis 400-800mg acyclovir daily throughout the sports season

HSV meningitis in association with genital disease: There is no standard of care (PubMed). The best review to date suggests "Most patients with HSV meningitis rapidly improve, but immunocompromised hosts have more neurologic sequelae and may benefit from antiviral therapy. Our data suggest symptomatic treatment alone for immunocompetent patients with HSV meningitis, avoiding the cost and side effects of prolonged intravenous acyclovir therapy; in contrast, immunocompromised patients had improved outcomes and would therefore benefit from antiviral therapy (PubMed)."

There is no data to support treating with iv acyclovir, I would give po and treat it like any other genital outbreak; expert opinion will differ, so I wonder if they are really experts.

Recurrent aseptic meningitis is usually due to Herpes 2 (Molleret's) and if associated with eye/urethra symptoms, think of Bechets.

Unfortunately, not only is chronic suppression with valacyclovir for recurrent HSV meningitis no better than placebo, when the medication is stopped there is a rebound with an increased frequency of disease (PubMed).

Notes

1/5 of Americans are seropositive for HSV, only 10% have ever been symptomatic. Most HSV is spread asymptomatically. Here in PDX an asymptomatic male spread HSV to a female and he was successfully sued for $900,000 (Ref).

This is an important fact: when a couple has been together for a while and one comes down with a whopping case of HSV and the other has never had it, it does not mean the positive partner is cheating; it means the negative partner is an asymptomatic shedder. Probably. Serologies will help. If the asymptomatic person is seronegative, then, indeed, the patient with herpes is probably a cheatin' pig.

Asymptomatic reactivation is common: "Twenty-four percent of anogenital reactivations and 21% of oral reactivations lasted <=6 h, and 49% of anogenital reactivations and 39% of oral reactivations lasted <=12 h. Lesions were reported in only 3 (7%) of 44 anogenital reactivations and 1 (8%) of 13 oral reactivations lasting <=12 h (PubMed)."

If it doesn't respond to acyclovir, it may be a resistant (thymidine kinase negative) strain usually HIV patients on long term suppression, then use foscarnet.

Of interest, if you cut out the trigeminal nerve of (hopefully) dead people you can find acyclovir resistance subpopulations (PubMed).