Presentation on theme: "Immunisation Update By Sindy Lee & Eva Wong 27th March 2003."— Presentation transcript:
1Immunisation UpdateBy Sindy Lee & Eva Wong27th March 2003
2Case 1Mr and Mrs Chan bring their 2 month old daughter, Siu-yee for her first immunisation. They say that they have received a reminder letter from the government and ask what their child what their child requires.
3Question 1What immunisation does the child now require?
4Question 2How and in what sites are these immunisation given?
6Question 4Where and how should the vaccination be recorded?
7Question 5The parents ask about possible reactions to the vaccines. What advice would you give about possible adverse reaction?
8Question 6Mr Chan returns in 2 months for Siu yee’s sencond immunisation and tells you she had a fever after her last immunisation. She cried during the night. What questions would you ask Mr Chan? What would you advise about this immunisation?
9Question 7You next see Siu-yee at the age of 6 months when she has a slight rhinitis but no fever and her chest is clear. Would you give her immunisation? What precaution would you take?
10Case 2Siu-ming, an 18 month old infant is brought for his fourth triple antigen immunisation. You have not seen him before.
11Question 1What information would you requires before giving the injection?
12Question 2The parent informs you that Siu-ming had his 12month booster at another private doctor’s clinic. The boy has not had an examination since relocating 12 months ago. What questions would you like to ask about his general health and development?
14Question 4The parent informs you that although there are no hearing problems in the family, Siu-ming does not seem to turn around when spoken to. Otoscopic examination reveals some mucosal swelling and a dull drum on the left side. He has a slight post-nasal drip but is afebrile.Would you give his immunisation?
15Question 5What is your management of the ear problem?
16Case 1Mr and Mrs Chan bring their 2 month old daughter, Siu-yee for her first immunisation. They say that they have received a reminder letter from the government and ask what their child what their child requires.
17Question 1What immunisation does the child now require?
18Question 2How and in what sites are these immunisation given?
26Case 1- answer 3 Stored 2-8C Upper deck: Middle deck: oral polio, MMR, BCG, rebellaMiddle deck:hepatitis B, DTP, fluLower deck: emergency medication, NSThermometer for monitoringNot to store with other foodsMinimize openingNew drug at the back
27Question 4Where and how should the vaccination be recorded?
28Case 1- answer 4 In practice record In child health record Immunization recordInformation:DateVaccineAdverse reactionExpiratory date and serial number
29Question 5The parents ask about possible reactions to the vaccines. What advice would you give about possible adverse reaction?
31Question 6Mr Chan returns in 2 months for Siu yee’s sencond immunisation and tells you she had a fever after her last immunisation. She cried during the night. What questions would you ask Mr Chan? What would you advise about this immunisation?
32Case 1- answer 6 ? Body temperature Describe the crying If temp >40.5C or crying >3-4 hr, child should preclude further pertussis vaccinationConsider prophylactic panadol
33Question 7You next see Siu-yee at the age of 6 months when she has a slight rhinitis but no fever and her chest is clear. Would you give her immunisation? What precaution would you take?
34Case 1- answer 7 Rhinitis not a contraindication Principles: Careful educationManagement of feverImmunisation should not be inappropriately deferred due to infection
35Case 2Siu-ming, an 18 month old infant is brought for his fourth triple antigen immunisation. You have not seen him before.
36Question 1What information would you requires before giving the injection?
37Case 2 – answer 1 Check previous immunisation record Any adverse reactionAllergiesPast medical historyNeurological diseases
38Triple vaccine Contraindication: Acute febrile illness Active or progressive neurological diseasePrevious severe reaction e.g. encephalopathy within 7 days after previous injection, immediate severe allergic or anaphylactic reaction
39Triple vaccine Relative contraindications Convulsion within 2 days Persistant, inconsolable screaming for more then 3 hours within 2 daysCollapse or shock like state within 2 daysUnexplained high fever with 2 daysSever local reaction
40Triple vaccine NOT contraindications: Family history of adverse reactionFamily history of convulsionPermaturityAsthma, eczema, allergiesStable neurological condition
41Question 2The parent informs you that Siu-ming had his 12month booster at another private doctor’s clinic. The boy has not had an examination since relocating 12 months ago. What questions would you like to ask about his general health and development?
42Case 2 – answer 2 Check previous health record Discuss developmental milestone
44Case 2- answer 3 Height and weight Strabismus Gait Abdomen and testis CVS
45Question 4The parent informs you that although there are no hearing problems in the family, Siu-ming does not seem to turn around when spoken to. Otoscopic examination reveals some mucosal swelling and a dull drum on the left side. He has a slight post-nasal drip but is afebrile.Would you give his immunisation?
47Question 5What is your management of the ear problem?
48Case 2 – question 5 Dx: serous otitis media Take 3 months to resolve Conservative managementRefer ENT if parents concern or persistent symptomsPrevent learning and language developmental problem
49Categorization of vaccines Live or inactivated ?Live attenuatedBCGInactivatedIPVOPVLive attenuatedMMRLive attenuatedChickenpoxLive attenuatedHepatitis BHep B surface anitigenDPTD&T toxoid, killed P organismInfluenzaInactivated vaccineHaemophilus influenzae type BInactivated
50Are they contraindication for vaccination? NoFamily history of any adverse reactions following immunisationFamily history of convulsion or epilepsyPrematuritySymptomatic HIVHistory of anaphylactic reactionNeurological conditions, such as cerebral palsy and Down’s syndromeThose on immunosuppressive agents eg. steroidsAsthma. ezema, hay fever, rash to egg protein to receive MMRThose on antibiotic or inhaled steroidPregnancyChild is being breastfeedUnder a certain weightChronic illness eg. congenital heart diseaseNoNoYesYesNoNoNoNoYesNoNoNo
51Routine immunization programme - BCG Characteristic:Intradermal, papule will appear 2-6 weeks then dischargeEfficacy:Protect against disseminated disease and TB meningitis in particular 80%About 50% protection against pulmonary TB
52Routine immunisation – BCG Adverse reaction 1-2%Prolonged deep ulceration, subcutaneous abscessLymphadenitis 1-10%Osteomyelitis 5/100,000 in newbornDisseminated disease <2/1,000,000
53Routine immunisation - BCG ContraindicationsChildren born to HIV-positive mothersThose at risk of severe immunodeficiencySymptomatic HIV (if asymptomatic, assessed by paediatrician for fitness)Those receiving immunosupressive agentsPregnancy
55Routine immunisation – Poliovirus vaccine How long did the faecal excretion of OPV last?6 weeksWhat happen if the child vomit after ingestion of OPV?Repeat if vomiting within 10 minutes. If not retained, repeat 4 weeks later.
56Routine immmunisation – Poliovirus vaccine OPVIPVTiming of vaccination2 separate doses (8 wks, min 6 wks) & a booster dose at 18 months ( min 2 mths after).2 injections (8 wks, min 4 wks) & a booster dose 1 year afterAdverse effect:Paralytic poliomyelitis (1/6.2 million)Contraindication:Anaphylactic reaction to a vaccine or any of its components (eg. Neomycin, streptomycin, polymyxin B)
57Routine immunisation - DPT PertussisDiphtheria toxoidTetanus absorbed toxoidEfficacy50-90%97%100%Adverse event:Local and febrile reactionBacterial or sterile abscesses /millionAllergic reaction – anaphylaxis 2/100,000Seizures – febrile seizuresHypotonic-hyporesponsive episode /100,000Fever of %
58Routine immunisation – DPT Contraindication:An immediate anaphylactic reactionEncephalopathy within 7 daysIs history of febrile convulsion a contraindication for DPT vaccination?How would you advise him?
59Routine immunisation - DPT Management of Children with history of febrile convulsion after DPTAdministration of panadol at the time of DPT and at 4-8 hours after immmunisation decreases the subsequent incidence of febrile and local reactions. Antipyretic prophylaxis every 4-6 hours for as long as 24 hours after vaccination may benefit children with increased risk of seizures, including febrile convulsionsTepid spongingRegular checking of body temperature
60Routine immunisation - MMR MeaslesRubellaMumpsEfficacy99%96%Adverse reactionFever 7-12 days after 5-15 %Rash 5%Allergic reactionSeizures – simple febrileThrombocytopenia 2-4/400,000 dosesEncephalitis - < 1 per million dosesArthopathy 0.5%Transient peripheral neurotic compliantsRashFebrile seizuresNerve deafnessMeningitis, encephalitis
61Routine immunisation - MMR Contraindication:Anaphylactic reaction to a vaccine or its components ( eg gelatin, neomycin)Immunodeficiency due to causes other the HIVSymptomatic HIVPregnancy
62Routine immunisation – Hep B Efficacy:90-95%Immune memory remains intact for >13 yearsSchedule:Three doses at birth, 1 and 6 monthsVery low birth weight infantsInfants < 2 kg respond poorly to vaccineIf mother HbsAg pos : start HBV vaccination with HBIg at birthIf mother HBsAg neg : start HBV vaccination when BW > 2 kgChildren under 6 years with incomplete course of vaccination ( the 3 doses)Received 2 doses 3 wks to 3 mths apart and within 1 year after second dose – give the third doseSupplementary Hep B vaccination for primary 6 students
67Polio vaccine Oral polio vaccine Developed 1961 Live attenuated vaccineCheap and easy to administerHumoral antibodies as well as intestinal immunityShort term shedding of vaccine in stool also result in “passive immunization” of persons with close contactsRisk of vaccine-associated paralytic poliomyelitis (VAPP)Declared polio-free in Oct 2000 in Western PacificRisk of VAPP greater then risk of paralytic poliomyelitis from wild-type poliovirus
68Inactivated polio vaccine Global eradication targeted at 2005Change to IPV?
69Inactivated polio vaccine (IPV) Developed 1955Immunogenicity is lowReplaced by enhanced-potency IPVNo risk of VAPPDisadvantages:ExpensiveNeeds additional injectionsIPV vaccinee is infected by wild polio, virus can still multiply and shed in stool risking continued circulation among the community
70Inactivated polio vaccine (IPV) During polio outbreak: OPVWHO recommendation:Countries currently involved in polio eradication should not consider using IPV at this moment and OPV is required for actual eradicationRecently or currently endemic countries should continue EXCLUSIVE OPV
71Is HK ready to switch to IPV? Last case of poliomyelitis caused by wild poliovirus occurred in HK in 1985Some Nearby areas still endemicSouth Asia countries reported 80% of global cases of polio in 1998Indian subcontinentSub-Sahara AfricaLack of data about risk of VAPP
72Polio vaccination in HK Oral trivalent vaccine introduced in 1963Resurgence of polio type 1 in 1965Oral polio type 1 to newborn in 19661971: Booster doses of trivalent vaccine at 18mo1979: booster doses at P.1 and P.6Strategy need review after global eradication of polio
74Influenza vaccine Epidemiology: Multivalent Two peaks: Jan-Mar, Jun-Aug2- 3 types of influenza virusesMultivalentComponent will be determined each year for northern and southern hemisphere97/98: Bayern(H1N1), Wuhan(H3N2)98/99: Sydney(H3N2), Beijing(H1N1)
75Influenza vaccine Inactivated vaccine Safe Efficacy age and immunocompetence of recipientdegree of match/similarity between vaccine strains and virus in seasonIf antigenicity similar, prevents illness in 70% - 90% of healthy persons <=65years
76Influenza vaccine- how to use? Different strain each yearAnnual vaccination1998: annual immunization of residents in elderly homes in HKGiven 2-4 months before its peakOctober to DecemberRoute: IM, ml
77Influenza vaccine- who should receive it? DHAll persons >65yearsResidents of nursing homeHAChildren with hemodynamically significant congenital heart disease, chronic lung disease (+/- asthma), children on long-term aspirin, hemoglobinopathies, psychogeriatric inpatients, institutionalized mental handicapped patientsPrivate:Anyone who wishes to reduce risk of influenza
78Intranasal influenza vaccine Trivalent, live attenuated cold adapted vaccineEffective (93% effective in preventing culture-positive influenza) and safeProtective even in the second year with serotype mismatch (86% effective)No injection needed
80Hepatitis A- epidemiology Incidence decreasing due to better hygieneFecal-oral route: hygiene > vaccinationUsually has a benign course51% of Guangzhou province and 15% HK has HA antibodiesExpensive
81Hepatitis A Two inactivated hepatitis A vaccines available Approved for persons > 2 years of agePediatric formulation availableDifferent units but 0.5ml IM for both2 doses (initial and at least 6 months later)
82Hepatitis A 88-100% seroconverted after 1st dose, 100% after 2nd dose Protective efficacy for clinical hepatitis A of %Need for booster dose not known yet, kinetic models suggest that protective levels will persist for > 20years
83Hepatitis ARoutine immunization for areas with rates >=20/ in the USHong KongLimited to high risk groups: travellers to endemic areas, chronic liver disease, laboratory workers, food handlers, health care workersNot routinely recommended for children“personal decision”Not a substitution for high standard of hygiene
85Varicella vaccine Epidemiology: Over 90% of children infected by 8 yearsHighly communicableComplications uncommon but seriousGreat economic impactTreatment of acyclovir remains in doubt
86Varicella vaccine Routine pre-exposure administration Overall 80-85% protection from infectionMilder disease for clinical diseasePost-exposure prophylaxisVaricella-zoster immunoglobulin (VZIG) within 96 hours of exposure: efficacy 50%, protection period unknownOral acyclovir: inadequate studiesPost-exposure immunization: encouraging results in Japan and US
87Varicella vaccine- post-exposure use Prevention of disease about %Milder clinical presentationSusceptible children with 72 hours and possibly up to 120hrs after exposure
88Varicella vaccine Live attenuated viral vaccine US: Institutional settingsTeachersNon-pregnant women of childbearing age (avoid pregnancy for 3 months afterwards)International travellersHealth care workersFamily members of immunocompromised patientsNOT needed for those with reliable hx of chickenpox
89Varicella vaccine HK: Epidemiology and burden largely unknown ? Cost-effectiveness of universal immunizationSelective immunizationHealthcare workers
90Varicella vaccine-specific contraindications Allergic reaction to neomycin, gelatin or prior dosePregnancyImmunodeficiency or those on immunosuppressive therapyOn aspirin (stopped for 6 weeks)Moderate or severe acute illnessMalignant neoplasms affecting bone marrow or lymphatic systems
91Meningitis- children killer? Meningococcal, pneunococcal and hemophilus influenza type B
92Meningococcal vaccine Quadrivalent polysaccharide vaccine (A,C,Y, W-135) and monovalent polysaccharide vaccines, efficacy <100%Men A vaccine in China (large outbreak in 1970s)
93Meningococcal vaccines US: 33% serogroup B, 28% group C, 34% group Y (1995-8)College students 0.6/100000Freshmen in dorm 4.6/100000Children 2-5yr 1.7/100000Not cost-effective
94Meningococcal vaccines UK:Growing burden of serogroup C in late 90s<1 yr: 31.5/1000001-4 yr: 16/100000Nov 1999, incorporated MenC conjugate vaccine into routine infant immunization (3 doses for <2m, 2 doses of 5-12mo)National campaign offering vaccine to everyone <18yr (1 dose)
95Meningococcal vaccine for HK? : 17 cases of infection (meningitis and septicemia) reported to DHIncidence of /10000081% local cases, 38% children <4 yrs4 serogroup B, 2 group A, 2 nonBJan 2000 – July 200124 cases reported79% local, same age distribution8 serogroup W-135
96Indication for useOutbreak control caused by strains with a capsular group contained in the vaccineHigh risk group:Complement deficiencyHypospleniaTravellers to highly endemic areas
97Conjugated pneumococcal vaccine Heptavalent conjugated pneumococcal vaccine trial involving >37000 children followed for 24 months found protective against both invasive disease (meningitis, pneumonia, septicemia) and acute otitis mediaSerotype-specific efficacy was 94% against invasive disease85% against bacteremic pnuemoniaLicensed in Feb 2000 in US
98Conjugated pneumococcal vaccine Heptavalent vaccineSerotypes (4, 6B, 9V, 14, 18C, 19F, 23F)In various sites of body (nasopharyngeal, mucosal and invasive)
99Should we use it in HK? Lack of documentation of disease burden Very few lab diagnosed bacteremia or meningitis in HA hospitalNo pneumococcal disease in HK?
100Haemophilus influenza type B Meningitis associated with high mortality and morbidity in Europe and North AmericaAnnual incidence: / of age <5 yrAnnual incidence in HK: 2.67/100000? Cost effectiveness? Combined vaccine
101Combination vaccine Simplify administration and promote compliance Technical difficulties and decreased immunogenicityWhole cell DTP-Hib, DTaP-Hib, DTaP-Hib-IPV, HepatitisB-Hib
102DTaP (acellular pertussis vaccines) VS DTwP (whole-cell pertussis vaccine) DTwP is effective but well known for post-vaccination fever (48hr) and local reatogenicity (swelling and induration) of injection siteDTaP causing less adverse effects and as effective as, if not more effective than DTwPCost-effective?Combination vaccines in future?