Mode of transmisison: droplet - one of most infectious!; R0 = 12-18 in developed countries

Incubation: 10d: maybe 7-18d from exposure to onset of fever

Period of infectivity: 5d before to 5d after rash onset - day of rash onset = d1

Vaccines: live attenuated vaccine

• MMR

• egg allergy NOT contraindicaiton

Schedule: 15mo and 4yr

efficacy: very effective

Herd: need 95% immunisation

• RNA virus

• humans = only natural host

clinical

• prodromal phase of 2-4days with:

  • fever

  • 3 C’s

    • cough

    • conjunctivitis

    • coryza

  • Koplik’s spots

• maculopapular rash

  • first behind ears on 3-7d

  • speads over from head and face -> trunk

• convalescnet stage

  • temporary brownish stain on skin

• complications

  • AOM

  • pneumonia

  • croup

  • diarrhoea

  • encephalitis:

    • 1:1000

      • 15% die

      • 25-35% left with permanent neurological damage

  • sub-acute sclerosing panencephalitis

    • fatal

    • typcially 7-10yrs after wild type measles virus infection

• vitamin a associated with dec mortality/morbidity

  • od for 2d at:

    • 200 000IU ≥12mo

    • 100 000 IU 6-11mo

    • 50 000 IU \<6mo

Expected response

• fever >39.4 in 5-15%

• lasts 1-2d

• rash 5%: 6-12d after immunisation

• most causes unrelated to immunisation

• mumps:; parotid and/or submaxillary swelling

• rubella; mild rash, fever, lymphadenopathy 2-4wl

• febrile seizures 1:3000 6-12d after immunisation

• increased fisk of ITP

During outbreak

• MMR can be given to unvaccinated people, who are not immunocompromised, within 72h of exposure - this may prevent infection

  • lahtough immune response may not be very effective; can be given 6-12mo if being reported in young children

  • still require 2 doses

• Human normal immunoglobulin

  • CI to MMR

  • immunocompromised children and adults

  • pregnant women

  • children \<15mo and >72hrs post exposure

  • >82hrs exposre no history or no MMR

  • given ASAP after eposure

    • can be given up to 6d

    • not within 3wk of live virurs

    • live virus not 11mo after

• IVIG - Intragam P

  • IV compared to IM

  • immunocompromised