Saad B. Omer Director, Yale Institute for Global Health The policy and epidemiology of mandates in the US & Europe @SaadOmer3
Saad B. OmerDirector, Yale Institute for Global Health
The policy and epidemiology of mandates in the US & Europe
@SaadOmer3
2
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
3
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
8
9
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
11
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
15
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.)
20
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
21
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
24
+ 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
25
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
26
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
27
28Omer, Betch, Leask; Nature; 2019
29
Acknowledgments
30
Thank You!
@YaleGH@SaadOmer3