Impact of Adverse Events Following Immunization

On Immunization Programmes

Strategic Communication WorkshopPublic Trust and Adverse Events Following

ImmunizationDelhi, August 9-10, 2004

Dr Anne GolazRegional Advisor, Immunization

UNICEF Regional Office for South AsiaKathmandu

Impact?

• Any documented impact of real AEFI or rumors of AEFI, on coverage, disease incidence, national vaccine policies?

• Impact of AEFI reported mostly from industrialized countries, very little written from developing countries

• Few documented examples from Europe and Africa, found in medical journals, and UN publications

• After this presentation, examples from South Asian countries: Afghanistan, Bangladesh, India, Pakistan

Nigeria, KANO state immunization boycott:International impact on polio eradication

August, 2003: OPV immunization halted in Kano state, Northern Nigeria, after rumors circulated by hardline religious clerics stating that:

“OPV vaccine could cause sterility in girls”

Nigeria: Kano state: from local to international impact

Endemic countries

Wild virus type 1

Wild virus type 3

Importations

Polio spread from Kano, to 10 countries:- Ivory Coast- Ghana- Togo- Benin- Burkina Faso- Cameroon- Central African Republic- Chad- Sudan- BotswanaPolio cases as of June 15, 2004

Soon after boycott started, Kano became epicenter of big and fast growing outbreak of polio, spread to whole country: 83% global cases from Nigeriathen to neighboring countries, including 10 that previously had been free of polio

Importations

Long-term impact of Kano boycott?

• July, 2004: 11-month ban on OPV lifted: campaign re-started

• Small fraction of hardliners in local government councils still not accept the vaccine because “governor succumbed to pressure of the federal government”

• Controversy over safety of polio vaccine generated rejection of all vaccines: could potentially threatened the acceptance of other beneficial health programs

• African countries with imported virus risk resurgence of disease as routine OPV3 <50%

• Conspiracy theories spread to other Islamic states: Pakistan and Afghanistan

Local impact: DPT3 and NID OPV reported coverage, 1997

by Province, KENYA

020406080

100

Nairo

bi

Centra

l

Coast

East

North e

ast

Nyanza

Rift v

alle

yW

est

Co

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%DTP3

OPV

Combatting Anti-vaccination Rumours:Lessons Learned from Case Studies in East Africa UNICEF Publication 2002

- Central province: educated population: highest routine coverage- Lowest NID OPV coverage, why?:1) Militant Catholic bishop led campaign against OPV: spread rumors about OPV associated with devil worship (color of OPV red, snake on the WHO logo)

2) Home to the political opposition; political atmosphere bred fear and distrust: since government never gave anything to people of the Central province, why OPV?

Mbarara district, UGANDADTP3 reported coverage, 1989-2000

0102030405060708090

100

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

Co

vera

ge

%

NID dates changed, coinciding with malaria peak season

Fears created by the deaths from malaria right after children received OPV in 1997, led to association of child deaths with NID season, and routine vaccination. Temporal association became a causal association in the mind of many

UGANDA: NIDs 1997-1999Reported OPV coverage

88

90

92

94

96

98

100

1996 1997 1998 1999 2000

Co

vera

ge

%

R1 R2

Anti-OPV radio broadcast #2Anti-OPV radio broadcast #1

Difference? In 1999, rumors broadcast made little impact: officials had a plan of action to counter rumors and educate people about immunization starting at the community level

Jordan: AEFI outbreak, 1998Small cluster of events: major national impact• September 1998: during annual nationwide school-based Td campaign: >800

teenagers believed they had suffered from side-effects of Td vaccine administered at school; 122 admitted at hospitals

• Schools were told to stop using the vaccine: event had started in 1 school, with a few affected students, and led to the interruption of the school-based immunization program in Jordan!

• Information spread outside school: TV and radio appeared on scene and rapidly disseminated story throughout country: parents panicked

• Investigation established that for a vast majority, symptoms did not result from vaccine, but mass psychogenic illness (“hysteria”), only ten cases true AEFI: rate AEFI found within the expected range of AEFI for Td

• After the investigation, the Jordanian Ministry of Health reinstated the Td vaccine and restored the public health confidence in immunization programme

• S Kharabsheh et al. Mass psychogenic illness following tetanus-diphtheria toxoid vaccination in Jordan. WHO Bulletin, 2001, 79(8);764-70.

Jordan: Context/background very important

• Number of negative rumors circulating about immunization at the time = background of suspicion

• Before outbreak of AEFI, strong anti-government feeling related to public water: debate just before on contamination of water detrimental to children’s health

• When press reported students hospitalized, “bad vaccine given by the government to our children” = government was to blame yet again

VACCINE REACTIONS

• Local Reactions

• Systemic Reactions

• Allergic Reactions

• Emotional

Jordan: Mixture of genuine mild side-effects from Td vaccine and psychologically-induced effects

Jordan: lessons learned

• Immunization campaign: large number of doses given over short period of time: more AEFI seem to occur

• Actual AEFI rate remains within expected range, sheer numbers involved during that period can produce clustering effect

• Relationship with media cannot be built up quickly during a crisis: long-term investments: provide the media with a continuous flow of information

• Rapid and clear response called for in a crisis

• AEFI surveillance system needed

Pertussis vaccination in Europe: Impact anti-vaccine movements in 1970-80s

• Sustained use of DTP• Low pertussis incidence

Hungary

Poland

East Germany

USA

Efficacy whole-cell pertussis vaccine! Vaccination controls pertussis!

• Decreasing coverage• Pertussis incidence increasing

Sweden

Japan

UKItalyWest Germany

Anti-vaccine movements!UK: 1974 report on 36 neurological reactions to pertussis vaccine

Gangarosa E. et al. Impact of anti-vaccine movements on pertussis control: the untold story. Lancet, vol 351, January 31,1998

93%

Vaccine uptake

81%

1940 1950 1960 1970 1980 1990

0

100

200

300

400

500

Year

Inci

den

ce p

er 1

00,0

00Incidence of pertussis in countries affected by

active anti-vaccine movements - England and Wales

1940 1950 1970 1980 1990

DTP introduced

81%

31%

Cas

es p

er 1

00,0

00

Year

Active anti-vaccine lobby

Gangarosa E. et al. Impact of anti-vaccine movements on pertussis control: the untold story. Lancet, vol 351, January 31,1998

1960

Sweden: impact on national policies

• Pertussis vaccination started in 1950s

• In 1967, influential medical leader: pertussis milder disease because of social, medical progress: questioned need for vaccine

• By 1975, pediatricians lost confidence in pertussis vaccine: cases occurred in vaccinated children and some neurological events were blamed on the vaccine

DTP coverage decreased from 90% in 1974 to 12% in 1979

• 1979: National policy change: abandon pertussis vaccine

• 1980s: Sweden reported > 10’000 case /year; >100/100’000

Whole-cell pertussi vaccine coveragesubstantially decreased

1940 55 70 85

Sweden

Sweden and Norway

Gangarosa et al., Lancet

National policy changedDPT not recommended

DTP coverage fell from 80% in 1974 to 10% in 1976

Pertussis epidemic occurred in 1979 with > 13’000 cases/ 41 deaths, + complications (pneumonia, encephalopathy, seizures)

Current vaccine scares: Potential threats Current vaccine scares: Potential threats to national and international immunization to national and international immunization

programsprograms

UK: MMR and autism

• 1997, considerable national media interest in possible adverse effects of MMR

• In Wales, MMR uptake declined 14% in the distribution area of a local newspaper covering MMR story aggressively, as compared to 2.4% decline in other areas of Wales

• In 3 months, local paper had published 5 front page headline articles, 3 opinions, 18 other articles on MMR

B. Mason et al. Impact of a local newspaper campaign on the uptake of MMR vaccine. J Epidemiol Community Health, 200; 54:473-74 Dec;20(4):1099-106

MMR and autism: Lessons learned

• Most people learn about medicine and science from newspaper, magazine stories, radio, TV programmes and the internet

• Most parents trust health care providers: in Attitudes, Knowledge and Practice survey of physicians in Italy: most important factor in decision of parents to vaccinate

• Health care workers must be trained to be well informed of both benefits of immunization as well as issues of parental concern regarding vaccine safety

• Engage the news media, train health care workers!

Impact of AEFI Summary: lessons learned

• Local impact national international

• To build public trust in vaccine:

• Importance of media and health care providers in giving correct information about vaccine

• Importance of background of trust: lack of information, religious opposition, distrust of central government on other issues (poverty and marginalisation of underserved population at the root of popular disgruntlement: refusal of vaccine)

• Importance AEFI surveillance for monitoring of immunization safety

Maturity

Incidence

Disease

VaccineCoverage

AdverseEvents

PrevaccineIncreasingCoverage

1Loss ofConfidence

Outbreak

VaccinationsStopped

Eradication

Eradication

2 3 4 5

Resumption of Confidence

Evolution of Immunization Programs and Prominence of Vaccine Safety

ab

Conclusions

• Take AEFI seriously: they can have serious impact on immunization programmes

• Paradox: successful disease-control encourages complacency; as VPD become rarer, attention shift from disease to adverse events: set the stage for movements opposed to vaccination

• Loss of confidence resurgence of disease

Thank you!