Effectiveness & cost-effectiveness of vaccinating healthcare workers against influenza, and strategies to improve uptake
Dr Rachel Jordan University of Birmingham, UK
Amanda Burls, Beverley Wake, Pelham Barton, Babatunde Olowokure, Esther Albon, Jeremy Hawker
Overview
Background Effectiveness of influenza vaccine
in HCW Effectiveness in protecting patients Cost-effectiveness Barriers Interventions to improve uptake
Influenza vaccine and HCW
Influenza important public health problem…
Significant mortality & morbidity in elderly & high risk groups
Vaccinate most at risk Also provide indirect protection eg HCWs,
carers Recommended by WHO (& most of Europe) Uptake in Europe <25% [UK~13%]
Methodology
Series of systematic review sub-q’s Cochrane Library, MEDLINE, EMBASE
etc to June 2004 Independent data extraction & quality
assessment Primary studies – series of questions Updates
Effectiveness in HCW
Study DescriptionVaccine
match/epidemic
Wilde1992US
RCTVaccine v placebo
3 years361 person-
winters.
Year:1- Partial2- Good3- PartialEpidemic each
yr.
VACCINEEFFICACY
88% (47%, 97%)for Influenza
A(H3N2)89% (14%, 99%)for Influenza B.
Weingarten
1988US
RCTVaccine (91) v
placebo (88)
Poor match.Epidemic
present
ADVERSEEVENTS
Sore arm51% vaccinated vs
7% p<0.05Erythema
11% vaccinated vs 0% control
p<0.05
Demicheli2000
Systematicreview
3 RCTs
Good matchEpidemic
present
ABSENTEEISMIN HEALTHY
ADULTS
Reduction:0.4 days/person
vaccinated (95%CI 0.1, 0.8)
Protection for patientsPotter 1997 Carman 2000 Hayward 2006
Influenza epidemic
1994-5 1996-7 2003-4
Number of clusters
12 20 44
Setting Long-term-care geriatric hospitals in Scotland UK Care homes
Vaccine match Reasonable match
Good match Reasonable match
Number of HCW 1078 offeredvaccination
1217 offered vaccination 1743 (884 int/859 control) offered vacc
HCW vaccine uptake rate
Control = not given
Intervention = 61%
Control = 5%Intervention = 51%
Control = 5.9%Intervention = 48.2%
Number of patients
1059 (490 intervention569 control)
1437 (749 intervention 569 control)
2604(1233 intervention 1371 control)
Mortality results 17% (control) 10%
(intervention)p=0.013 (OR 0.56)
154/688 (22.4%) control102/749 (13.6%)
intervention OR 0.58 (95%CI 0.4-
0.84) Adj: OR 0.61 (0.36-1.04)
203/1323 (15.3%) con140/1249 (11.2%) interventionRate Diff -0.05 (-0.07, -0.02)
Cost-effectiveness Methods: Simple economic model
HCW Vaccination programme vs no prog Carman et al 2000 UK 2003-4 costs
Staff, vaccine, absenteeism Benefits discounted at 3.5%
Patient mortality, life expectancy Updated to include Hayward 2006 et al
Results
Carman 2000:
Base case Cost saving £12/vaccinee
No absenteeism CE £51/life yr gained
Pessimistic scenario
CE £405/life yr gained
Hayward 2006: pessimistic
CE £274/life yr gained
Barriers to vaccination
Large number of surveys Variety of designs,
settings and personnel Range of response rates
COMMON REASONS FOR REFUSING Fear of side effects Fear vaccine causes
flu Dislike of injections Unaware available Unaware useful Forgetting/lack of
time Perceived low risk of
contracting influenza
How do we improve uptake?
Common themes: Convenience & education
5 RCTs – range of interventions
Many before/after studies or descriptive evaluations of programmes
Evidence….RCTs Promotional/education campaigns –
little effect?Study Intervention Control
Dey 2001Manchester, primary care teams
Letter; posters; PH Nurse promotion: 21.9%
Letter: 21.0%
Kimura 2007S California
Educational campaign: 34% OR 1.3 (95%CI 0.8, 2.3)
No intervention27%
Doratotaj 2008Ohio: Tertiary care
Educational letter: 39%Letter + raffle: 44.5% (NS diff)
No offer: 38%
Evidence….RCTs Promotion + education + local
vaccination
Study Intervention Control
Hayward 2006UK nursing homes
Lead nurse promotion; letter; vacc clinics: 35.4%
No offer: 5%
Kimura 2007S California
Educational campaign + vaccine day: 53% OR 3.5 (95%CI 2.2, 5.7)
No intervention27%
Evidence….before/after Mobile carts – potential greatest effect?
Study Intervention Before After
Cooper 2002Australia - hospital
Mobile cart + promotion“Needles on Wheels”
8% 49%(81% in staff with pt contact)
Sartor 2004France – acute care hospital
Educational campaign + mobile cart
6% 32%(71% medical staff)
Evidence…. Combinations of:
Information/marketing convenience
Vaccine clinics + mandatory declination report via intranet eg Bertin 2007, Cleveland Hospital 55% after vs 38% before
Convenience + individual feedback & follow-up eg McCullers 2006, Pediatric Cancer
Hospital 80% after vs 45% before
Conclusions
Vaccinating HCW is effective & cost-effective
Uptake is still low Barriers are known Still lack of trials demonstrating
best methods of improving uptake
Implications
We need good RCTs of methods to improve uptake
Mobile carts combined with other methods promising
Mandatory declination? Individual feedback/follow-up?
Acknowledgements
Main funders: European Scientific Working Group on Influenza