Table 1:

Distinguishing infectious causes of vesicular lesions

CharacteristicMonkeypoxChickenpox and herpes zosterHSV-1 and HSV-2SyphilisHand, foot and mouth diseaseMolluscum contagiosum
Infectious causeMonkeypox virusVaricella zoster virusHerpes simplex virusTreponema pallidumCoxsackievirus A and several other enterovirus serotypesPoxvirus (molluscum contagiosum virus)
Subclinical sheddingNo*YesYesNoYesNo
Incubation period, d5–2110–212–123–903–514–180
Systemic symptomsPossible prodrome of fever, malaise, myalgias, headache.Primary: a prodrome of fever, malaise, pharyngitis, anorexia. Reactivation: minority have fever, malaise, headache.Primary: fever, malaise, myalgias, headache, tender lymphadenopathy. Reactivation: prodromal tingling or shooting pains.UncommonProdrome is uncommonNone
LymphadenopathyTender, regionalPrimary: generalized. Reactivation: regional.Tender, regionalPrimary: painless, regional. Secondary: generalized.CervicalNo
RashMacules to papules to vesicles to pustules that umbilicate, ulcerate, crust and desquamate. Local pain and pruritis until crusting. Lesion pleomorphism.Primary: maculopapular, vesicles, scabs appearing in crops. Lesions in all stages. Pruritic. Reactivation: erythematous papules to pustules. Can be hemorrhagic. Crust by 7–10 days.A cluster of 2–4 mm vesicles on an erythematous base. May progress to vesicopustules and ulcers. Local pain and pruritis.Primary: chancre. Secondary: maculopapular, may coalesce. Superficial mucosal erosions. Pustules. Condyloma lata. Rarely vesicular.Oral: 1–5-mm erythematous vesiculoulcerative stomatitis Exanthem: macular, maculopapular, or 1–10-mm vesicular on palms, soles, legs, and arms. Lesions may be at different stages of development. Local pruritis.2–5-mm firm, dome-shaped flesh-coloured papules with umbilication. Rarely painful.
LocationPrimary: site of inoculation. Secondary: spreads to extremities.* Can involve palms and soles.Primary: head, scalp, trunk, extremities. Reactivation: dermatomal.Orofacial, genitalia, rectum, hands, eyesPrimary: site of inoculation. Secondary: most commonly on palms and soles, trunk and extremities, intertriginous and mucosal areas.Oral, palms, soles, arm, legs, buttocksAnywhere on body, but uncommon in mouth or on palms and soles
DiagnosisViral PCR of unroofed lesion (dry flocked swab), throat or nasopharyngeal swab, serum sample or urine sample (currently all samples are being investigated)Viral PCR of lesion swabViral culture or viral PCR of lesion swabSerologyClinicalSkin biopsy showing keratinocytes with eosinophilic cytoplasmic inclusion bodies
TreatmentSupportive; antiviral drugs restricted to high-risk cases and are not widely available outside of a clinical trialAcyclovir, valacyclovirAcyclovir, valacyclovirPenicillinSupportiveSupportive
  • Note: HSV = herpes simplex virus, PCR = polymerase chain reaction.

  • * Being challenged in the 2022 outbreak. Investigations are ongoing.