1 / 26

UNDERSTANDING VACCINE REACTIONS

UNDERSTANDING VACCINE REACTIONS. CONTRAINDICATIONS. True contraindications are rare Current serious febrile illness delay vaccine administration History of severe AEFI after previous dose Evolving neurological disease avoid whole cell pertussis vaccine (e.g. uncontrolled epilepsy)

christinacsmith
Download Presentation

UNDERSTANDING VACCINE REACTIONS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. UNDERSTANDING VACCINE REACTIONS World Health Organization

  2. CONTRAINDICATIONS True contraindications are rare • Current serious febrile illness • delay vaccine administration • History of severe AEFI after previous dose • Evolving neurological disease • avoid whole cell pertussis vaccine • (e.g. uncontrolled epilepsy) • Type 1 hypersensitivity to egg - avoid yellow fever & influenza but can use vaccines made in chick fibroblasts • Symptomatic HIV • avoid BCG and yellow fever WHO Immunization Policy 1996 World Health Organization

  3. Vaccine Contraindication All vaccines Anaphylactic reaction to vaccine or vaccine constituent Severe febrile illness DTP Encephalopathy within 7 days of administration OPV Immunodeficiency, or immunodeficient household contact* IPV Anaphylactic reaction to neomicin, streptomycin or polymyxin B CONTRAINDICATIONS Adopted from Plotkin pg 66-67 * Risk benefit assessment when administered to HIV positive individuals World Health Organization

  4. Vaccine Contraindication MMR Anaphylaxis, pregnancy, immunodeficiency* Hib None Hepatitis B Anaphylactic reaction to common baker’s yeast Yellow fever Anaphylactic reaction to egg, immunodeficiency CONTRAINDICATIONS Adopted from Plotkin pg 66-67 * Risk benefit assessment when administered to HIV-positive individuals World Health Organization

  5. WHAT IS AN ADVERSE EVENT FOLLOWING IMMUNIZATION (AEFI)? A medical incident that takes place after an immunization, causes concern, and is believed to be caused by immunization • Vaccine reaction - caused by vaccine’s inherent properties • Programme error - caused by error in vaccine preparation, handling, or administration • Coincidental - happens after immunization but not caused by it • a chance association • Injection reaction - anxiety or pain of injection not vaccine • Unknown -cause cannot be determined World Health Organization

  6. VACCINE REACTIONS • Common, minor reactions • vaccine stimulates immune system • settle on their own • warn parents and advise how to manage • Rare, more serious reactions • anaphylaxis (serious allergic reaction) • vaccine specific reactions World Health Organization

  7. COMMON, MINOR REACTIONS Local reaction (pain, swelling, redness) Irritability, malaise & systemic symptoms Vaccine Fever >38C - 90-95% - BCG - 5-15% 2-10% Hib - 1-6% HepB Adults: 15%; Children: 5% Measles/MMR 5% rash ~10% 5-15% Polio (OPV) <1% - <1%** ~10%* ~10% ~25% Tetanus DTP (pertussis) Up to 50% Up to 50% Up to 55% * Rate of local reactions likely to increase with booster doses, up to 50-85% ** Symptoms include diarrhoea, headache, and/or muscle pains World Health Organization

  8. MANAGEMENT OF COMMON, MINOR REACTIONS • Local reaction • cold cloth at injection site • paracetamol • Fever >38°C • give extra fluids • tepid sponging • paracetamol • Irritability malaise and systemic symptoms • give extra fluids • paracetamol World Health Organization

  9. RARE, MORE SERIOUS REACTIONS Vaccine Reaction Onset interval Rate per million doses BCG Suppurative lymphadenitis BCG osteitis Disseminated BCG 2-6 months 1-12 months 1-12 months 100-1000 1-700 2 Hib Nil known Hep B Anaphylaxis Guillain Barré syndrome 0-1 hour 1-6 weeks 1-2 5 Measles /MMR Febrile seizures Thrombocytopaenia Anaphylaxis 5-12 days 15-35 days 0-1 hour 333 33 1-50 OPV Vaccine-associated paralytic poliomyelitis (VAPP) Risk is higher for first dose, adults, and immunocompromised 4-30 days 0.76-1.3 (1st dose) 0.17 (subsequent doses) 0.15 (contacts) World Health Organization

  10. Vaccine Reaction Onset interval Rate per million doses Tetanus Brachial neuritis Anaphylaxis Sterile abscess 2-28 days 0-1 hour 1-6 weeks 5-10 1-6 6-10 Tetanus-diphtheria Nil extra to tetanus reactions DTP Persistent (>3 hrs) inconsolable screaming Seizures Hypotonic, hyporesponsive episode (HHE) Anaphylaxis/shock Encephalopathy 0-24 hours 0-3 days 0-24 hours 0-1 hour 0-3 days 1000-60 000 570 570 20 0-1 RARE, MORE SERIOUS REACTIONS (2) World Health Organization

  11. ADVERSE EVENTS ASSOCIATED WITH SPECIFIC VACCINES • WHO case definitions are used here • Lack of standardized case definitions in the literature • e.g. fever • The Brighton collaboration • developing case definitions for AEFI • promoting global implementation of these definitions secretariat@brightoncollaboration.orghttp://brightoncollaboration.org World Health Organization

  12. ANAPHYLAXIS • Type 1 hypersensitivity reaction • Circulatory failure • Bronchospasm +/- laryngospasm/laryngeal oedema • respiratory distress • May include pruritis, flushing, angioedema, seizures, vomiting, abdominal cramps & incontinence • Occurs in previously sensitized individuals World Health Organization

  13. ANAPHYLAXIS • Reported less from developing countries • Less sensitization? • Less reporting? • Anaphylaxis is rare (1/1 000 000 vaccinations) • Fainting is common • Untrained staff may misdiagnose fainting/dizzinessfor anaphylaxis or vice versa • Administration of adrenaline in a faint may bedangerous • PROMPT MANAGEMENT IS VITAL! World Health Organization

  14. SEIZURES • Particularly associated with measles and DTP vaccination (pertussis component) • febrile seizures Temp >38 • afebrile seizuresTemp normal • Febrile seizures more common with pertussis • An association with non-febrile seizures has not been proven World Health Organization

  15. ADVERSE REACTIONS TO BCG Disseminated BCG • widespread infection, 1-12 months after BCG • usually in immunocompromised individual • confirm by isolation of Mycobacterium bovisBCG strain • treat with antituberculous regimen including Rifampicin and Isoniazid Osteitis/osteomyelitis • infection of the bone with M bovis BCG strain • management as above World Health Organization

  16. ADVERSE REACTIONS TO BCG Suppurative lymphadenitis • occurs within 2-6 months of BCG vaccination • case definition • 1 lymph node> 1.5 cm in size/draining sinus over a lymph node • usually occurs in the axilla, on the same side as innoculation • Management • heals spontaneously over months • only treat if sticking to skin or draining • surgical drainage and local installation ofantituberculous drug • systemic Rx is ineffective World Health Organization

  17. World Health Organization

  18. World Health Organization

  19. TETANUS VACCINE Brachial neuritis • Presents with pain in shoulder and upper arm • Followed by weakness +/- wasting of arm and shoulder muscles • Sensory loss not prominent • Occurs 2-28 days after vaccination • Possibly a manifestation of immune complex disease • Management is symptomatic World Health Organization

  20. ENCEPHALOPATHY AND ENCEPHALITIS Possibly associated with measles & pertussis vaccine • Case definition of encephalopathy • 2 out of 3 of • seizures • alteration of consciousness lasting for one day or more • distinct change in behavior for one day or more • Temporal relationship • within 48 hrs with DTP • within 7-12 days after measles or MMR World Health Organization

  21. ENCEPHALITIS AND MEASLES VACCINATION • An analysis of claims for encephalitis following measles vaccine in the USA found clustering of events 8-9 days after vaccination (Wetbel 1998, Duclos 1998) • This supports, but does not prove, thepossibility that measles vaccine was causative • Risk is less than 1 case per million World Health Organization

  22. HYPOTONIC HYPOTENSIVE EPISODE (HHE OR SHOCK-COLLAPSE) • Mainly associated with DTP • Case definition • Event of sudden onset occurring within 48 (usually less than 12) hours of vaccinationand lasting from one minute to several hours • In a child < 10 years of age • ALL of the following must be present • limpness (hypotonic) • reduced responsiveness • pallor or cyanosis - or failure to observe/recall • Transient, self-limiting, NOT a contraindication to further vaccination World Health Organization

  23. POLIO VACCINE - ACUTE FLACCID PARALYSIS Vaccine associated paralytic poliomyelitis • Occurs within 4-30 days of receipt of OPV or 4-75 days after contact with vaccine recipient Case Following a national immunization day in 1996, cases of paralysis were reported after receiving OPV. On laboratory analysis, the wild virus was found, showing that the children had been infected with wild poliovirus before immunization. The cases of poliovirus were coincidental, and not caused by the vaccine. World Health Organization

  24. UNPROVEN ASSOCIATIONS AND PUBLIC CONCERNS • Influenza vaccine and Guillaine Barré Syndrome • MMR and autism, Crohn’s disease • Polio and HIV • Hepatitis B and multiple sclerosis • DTP and permanent brain damage • DTP and increased risk of mortality • Aluminium and macrophagic myofasciitis • Bovine spongiform encephalopathy (BSE) • Thiomerosal • Multiple vaccines given simultaneously World Health Organization

  25. TOXIC SHOCK SYNDROME A one-year-old child died within 12 hours of receiving measles vaccine. It was reported as a possible anaphylaxis because of its rapidonset. Investigation found that the vaccine used was likely to have been reconstitutedsome days prior to this particular use. Cause: Non sterile injection: NOT ANAPHYLAXIS!!! World Health Organization

  26. Vaccine BCG OPV Measles DTP Estimated rate of serious reactions 1/1000 to 1/50 000 doses 1/3 million doses for 1st dose OPV 1/1million doses 1/750 000 ESTIMATED AEFI RATES FOLLOWING CHILDHOOD VACCINES WHO web site - Dealing with adverse events - 2/19/99 World Health Organization

More Related