1. MEASLES

2. Measles  Highly contagious, acute exanthematous respiratory disease with a typical clinical picture and a characteristic enanthem: Koplik’s spots  Family: Paramyxoviridae  Genus: Morbillivirus

3. Classic measles: 1. Incubation  10-14/7 - enters through resp epithelium / conjunctiva, replicates locally, spreads to regional lymphatic tissue - disseminates to RES via blood stream

4. Classic measles: 2. Prodrome 3 /7 but up to 8/7 - appearance of symptoms : fever, malaise, anorexia and then cough, coryza, conjunctivitis - enanthem – Koplik’s spots

5. Koplik’s spots Pathognomonic “Grains of salt against a red back ground” Occurs 48hr before rash Often disappear with appearance of the rash

8. Classic Measles: 3. Exanthem  Maculopapular, blanching  Cranial-caudal progression  Face – neck, trunk and extremities  3-4 / 7 later – fade, changes to brownish colour with fine desquamation

10. Classical measles: 4. Recovery  Clinical improvement after 48hrs  Rash fades after 3 days  No more fever after > 3/7 after rash appeared

11. Diagnosis of measles  WHO: laboratory diagnosis – IgM  IgM: can be undetectable on the first day of exanthem -- from 3 rd day onwards for 30days  IgG: from day 7 of rash – peaks @ 14/7  False +: Parvo B19

12.  Giant cells with inclusions - conjunctival - nasopharyngeal - buccal epithelial cells - urine

13.  Viral cultures from mononuclear cells resp secretions conjunctival swabs urine  Special facilities, difficult

14. Complications  Fever > 3/7 after onset of rash = complications  Developing countries – mortality 10%  Poor nutritional status  Pregnant women  Immunocompromised patients

15. Pneumonia  2’ bacterial pneumonia Streptococcus pneumonia Streptococcus pyogenes Heamophilus influenza Staphylococcus aureus  Viral pneumonia – giant cell

16. Neurological complications  Acute disseminated encephalomeningitis  Subacute sclerosing panencephalitis

17. Acute disseminated encephalomyelitis Demyelinating During recovery phase – within 2/52 of exanthem Post-infectious auto-immune process Fever, headache, neck stiffness, ataxia, myoclonus, seizures, mental status changes LP : lymphocytic pleocytosis elevated protein Residual neurological abnormalities

18. Subacute sclerosing panencephalitis Progressively fatal degenerative CNS disease 7-10yrs after measles ? Pathogenesis – persistent CNS measles infection Stages: stage 1 – soft neurological signs stage 4 – severe deterioration, flaccidity, decorticate rigidity and autonomic dysfunction

19. Tracheobronchitis Otitis media Corneal ulceration and keratitis Myocarditis Pericarditis Mesenteric lymphadenitis Appendicitis Diarrhoea

20. Modified measles  Similar to classic measles, but milder  17 – 21/7  Partial immunity - babies: transplacental transfer of AB - live vaccine, with incomplete antibody response - rare: previous measles

21. Atypical measles Previously vaccinated with killed vaccine 7-14/7: fever, headache, cough, pleuritic pain Rash: from extremities to trunk (vesicular, petechial, purpuric, urticarial) Can cause severe illness Not infective IgM: @ onset of rash: titre< 1:5 day 10: 1:1280 Broad differential

22. Immune-supressed patients @ risk for severe, progressive measles Atypical presentation: - absence of rash - any rash – purpura / desquamating - giant cell pneumonia - measles inclusion body encephalitis - up to 6/12 later Deficient antibody synthesis Biopsies

23. Isolation  Infective 5/7 before exanthem till 4/7 after it started  Aerosol spread  Strict respiratory isolation  Private room with negative air ventilation  Masks should be worn at all times

24. Treatment  Supportive  Secondary infections  Vit A 200 000u po as stat dose

25. Vaccination  Live attenuated vaccine

26. Contra-indications  HIV with CD4 < 200  Glucocorticoid therapy >2mg/kg 20mg alternate days - wait 1/12  Leukaemia in remission – wait 3/12  Pregnancy  Gelatine allergy  Thrombocytopenia

27. Post exposure prophylaxis: Immunoglobulin  At risk: Immunocompromised Pregnancy Babies < 1yr  Within 6/7 of exposure  However, if not high risk and < 72hrs after exposure = Vaccinate

28. Thank you The greatest obstacle to discovery is not ignorance -- it is the illusion of knowledge." ~ Daniel Boorstin