3 days; Koplik's spotsRubella (German measles, third disease)Spreads from hairline downward, clearing as it spreads; Forschbeimer spotsErythema infectiosum (fifth disease)Brightred "slapped-cbeeks" appearance followed by lacy reticular rash that waxes and wanes over 3 weeks; rarely, papular-purpuric "gloves-and- socks" syndrome on hands and feetExanthem subitum (roseola, sixth disease)Diffuse maculopapular eruption over trunk and neck; resolves within 2 daysInfectious mononucleosisDiffuse maculopapular eruption (5% of cases; 90% if ampiciUin is given); urticaria, petechiae in some cases; periorbita] edema (50%); palatal petechiae (25%)Epidemic typhusMaculopapular eruption appearing in axillae, spreading to trunk and later to extremities; usually spares face, palms, soles; evolves from blanchable macules to confluent eruption with petechiae; rash evanescent in recrudescent typhus (Briil-Zinsser disease)Endemic (murine) typhusMaculopapular eruption, usually sparing palms, solesScrub typhusDiffuse macular rash starting on trunk; eschar at site of mite biteRickettsial spotted feversEschar common at bite site; maculopapular (rarely, vesicular and petechial) eruption on proximal extremities, spreading to trunk and faceHuman monocytotropic ehrlichiosis"Maculopapular eruption (40% of cases), involves trunk and extremities; may be petechialLeptospirosisMaculopapular eruption; conjunctivitis; scleral hemorrhage in some casesLyme diseasePapule expanding to erythematous annular lesion with central clearing (erythema migrans; average diameter, 15 cm), sometimes with concentric rings, sometimes with indurated or vesicular center; multiple secondary erythema migrans lesions in some casesTyphoid feverTransient, btanchable erythematous macules and papules, 2-4 mm, usually on trunk (rose spots)Dengue feverRash in 50% of cases; initially diffuse flushing; midway through illness, onset of maculopapular rash, which begins on trunk and spreads centrifugaily to extremities and face; pruritus, hyperesthesia in some cases; after defervescence, petechiae on extremities in some cases' Varicella(Chickeopox): A characteristic feature of rash is its peomarphism i.e, alt stage of rash (papules, vesicles & crusts) may be seen simultaneously at one time, in the same area. Temperature rise with each fresh crop of rash"- Park 23stf 144"Exanthem subitum (roseola) is caused by human herpesvirus 6 and is most common among children">