Herpes Simplex Virus

Question 1

Define:

Answer 1

• Disease resulting from HSV1 or HSV2 infection

Question 2

Aetiology/risk factors:

Answer 2

• Transmitted via close contact (e.g. kissing, sexual intercourse) with an individual that is shedding the virus
• Pathophysiology
o After primary infection, the virus will become dormant (within nerve ganglia)
o Reactivation may occur in response to physical and emotional stresses or immunosuppression
o The virus causes cytolysis of infected epithelial cells leading to vesicle formation

Question 3

Epidemiology:

Answer 3

• 90% of adults are seropositive for HSV1 by 30 yrs
• 35% of adults > 60 yrs are seropositive for HSV2
• More than 1/3 of the world population have recurrent HSV infections

Question 4

Symptoms HSV1:

Answer 4

primary infection is often asymptomatic
• Possible symptoms of primary HSV1 infection:
o Pharyngitis
o Gingivostomatitis (eating might be painful)
o Herpetic whitlow (abscess at the end of the finger caused by infection with HSV - it is very painful)

• Symptoms of reactivation of HSV1:

o Prodrome of perioral tingling and burning
o Vesicles appear - they will ulcerate and crust over
o Complete healing within 8-10 days

Question 5

Symptoms of HSV2:

Answer 5

o Painful blisters and rash in the genital, perigenital and anal area
o Dysuria
o Fever
o Malaise

Question 6

Symptoms of HSV encephalitis:

Answer 6

o Usually caused by HSV1 so causes HSV1 type symptoms

Question 7

Symptoms of keratoconjunctivitis:

Answer 7

o Watering eyes

o Photophobia

Question 8

Signs of HSV1:

Answer 8

o Primary is usually asymptomatic, but can cause pharyngitis, gingivostomatitis and herpetic whitlow
o Then HSV1 becomes dormant, usually in trigeminal nerve
o Reactivation presents as herpetic labialis (cold sores)
o Tender cervical lymphadenopathy
o Erythematous, oedematous pharynx
o Oral ulcers filled with yellow slough (gingivostomatitis)
o Herpetic whitlow

Question 9

Signs of HSV2:

Answer 9

o Maculopapular rash
o Vesicles
o Ulcers
o All of these are found on the external genitalia, anal margin and upper thighs

Question 10

Other signs:

Answer 10

o Dendritic ulcer on the iris (better visualised with fluorescein)

inguinal lymphadenopathy, pyrexia
• HSV2 Encephalitis
o Signs of encephalitis

Question 11

Investigations:

Answer 11

• Diagnosis is usually CLINICAL

* Vesicle fluid can be sampled and sent for electron microscopy, PCR