the policy and epidemiology of mandates in the us & europe · saad b. omer director, yale...

Saad B. OmerDirector, Yale Institute for Global Health

The policy and epidemiology of mandates in the US & Europe

@SaadOmer3

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Reasons For Non-Vaccination Among Measles Cases2000-2015

Other156 (31%)

Nonmedical exemptions

349 (69%)

43% of all cases

Phadke et al. JAMA, 2016

0

10

20

30

40

50

60

70

80

90

100

1 2 3 4 5 6 7 8 9

Percen

t of

mea

sles

ca

ses

Time in weeks

Vaccination status of measles cases by week

Unvaccinated

Unknown vaccination status

Vaccinated

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Cumulative Epidemic Curve of 16 Measles Outbreaks 2000 - 2015, United States

Phadke et al. JAMA, 2016

4

Brewer et al., Psychol Sci Public Interest. 2017

5

School Immunization Requirements

State laws (not federal)

3 types of exemptions allowed

1. Medical2. Religious

3. Personal belief(philosophical)

Major role in low rates of vaccine

preventable diseases

6

7

Ease of Obtaining Vaccine Exemptions –by State

Omer et al., New England Journal of Medicine . 2012Figure (with updated 2013 data) created by Mother Jones

Ease of Obtaining Vaccine Exemptions in the U.S. - by State

Exemption Policies & Whooping Cough Incidence, 1986-2004

Omer et al., JAMA, 2006

Exemption ease

Incidence Rate Ratio

Difficult Reference

Medium 1.35 (0.96-1.91)

Easy 1.53 (1.10-2.14)

Omer et al., New England Journal of Medicine . 2012Figure (with updated 2013 data) created by Mother Jones

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Non-Medical Exemptions by Year 1991 - 2003

0.0%

0.5%

1.0%

1.5%

1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003

Exe

mpt

ion

Rat

e

10

Nonmedical Exemptions for States With Religious Exemptions and With Personal Belief Exemptions

1991 - 2004

Data updated

Only Religious Exemptions Permitted Personal Belief Exemptions Permitted

Omer et al., Journal of American Medical Association, 2006

Nonmedical Exemptions by Ease of Exemption 1991 - 2007

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Easy Exemption Policy

Medium Exemption Policy

Difficult Exemption Policy

Data updatedOmer et al., JAMA, 2006

Mean (95% CI) Rates of Nonmedical Exemptions by Type of Exemption, 2006–2011

Omer et al., NEJM, 2012

Omer et al., New Eng Journal of Medicine, 2012 13

Mean (95% CI) Rates of Nonmedical Exemptions by Ease of Exemption,

2006–2011

Relative Locations of Pertussis Space-time Clusters & Exemptions Spatial Clusters

Unadjusted OR

3.0 (2.5 – 3.6)

Adjusted OR

2.7 (2.2 – 3.3)

Overlap of

Exemptions

Clusters with

Pertussis Clusters

Omer et al., Am. J. Epi., 2008

Washington Exemption Law

• SB 5005• Educational counseling and signed form from a licensed (in WA) health care

provider in order to obtain a nonmedical exemption

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1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

Law in effect July 22, 2011

Impact of Change in Washington Exemption Law

0%

2%

4%

6%

8%

10%

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

An

y Ex

emp

tio

n R

ate

Year

Overall (Before) Overall (After)

Regression Line (Before) Regression Line (After)

16Omer et al., Pediatrics, 2017

Omer et al., New Eng Journal of Medicine, 2009 17

WA State Counties’ School Entry Exemption Rates -2006-2007

19

Delamater et al., 2019, Pediatrics

Elimination of Nonmedical Immunization Exemptions in California & School-Entry Vaccine Status

(home schoolers etc.)

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Clusters of high not-up-to-date rates in California

Not Up-To-Date Rates

Pingali et al., 2019, JAMA

Association of State Non-medical Exemption Policies With Medical Exemption Rates

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Stadlin, Bednarczyk, Omer JID 2012

0

50

100

150

200

250

300

350

400

Difficult Medium Easy

Me

dic

al E

xem

pti

on

s /1

00

,00

0

Non Medical Exemption Category

Parent reports to VAERS increased after introduction of SB277 in California

10%

15%

20%

25%

30%

2011-12 2012-13 2013-14 2014-15 2015-16 2016-17 2017-18

Par

ent

rep

ort

s

CA

TX

SB2

77

Hause at al., unpublished data

Reporting time increased after introduction of SB277 (parent reports)

0

5

10

15

20

25

30

35

2011-12 2012-13 2013-14 2014-15 2015-16 2016-17 2017-18

Med

ian

tim

e to

rep

ort

School year

CA

TX

SB2

77

Hause et al., unpublished data

Association Between Mandatory Vaccination Policies and Measles Vaccination Rates

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+ 3.7 (1.7, 5.7) + 3,8 (1.2, 6.4)

+ 0,8 (0.5, 1.2)

0

1

2

3

4

5

6

7

Mandatory Vaccination* Mandatory Vaccination withoutNon-Medical Exemptions*

Financial Penalty for Non-Compliance (per €500)*

Perc

ent

Dif

fere

nce

(95

% C

I)

Differences in Measles Vaccination Rates by Vaccine Policy

*p-value < 0.01Vaz et al., Pediatrics, In press

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Association Between Mandatory Vaccination Policies and Pertussis Vaccination Rates

+ 2.1 (0.3, 4.2) + 2.1 (-1.7, 5.9)

+ 1.1 (1.0, 1.3)

-3

-2

-1

0

1

2

3

4

5

6

7

Mandatory Vaccination* Mandatory Vaccination withoutNon-Medical Exemptions

Financial Penalty for Non-Compliance (per €500)*

Perc

ent

Dif

fere

nce

(95

% C

I)

Difference in Pertussis Vaccination Rates by Vaccine Policy

*p-value < 0.05Vaz et al., Pediatrics, In press

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Effects of potential legislative and administrative actions on vaccine up-to-date rates

Delamater et al., Unpublished

Omer, New York Times (Op-Ed), Feb 2015

In-person counseling

Procedures to review each request for exemption

Sign a form that discusses the risks of non-vaccination

Letter elaborating on the reason their child should be exempt

Obtain the form by specifically requesting from the state or local health department, vs. downloading it online

Annual renewal

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28Omer, Betch, Leask; Nature; 2019

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Acknowledgments

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Thank You!

@YaleGH@SaadOmer3