Immunize or mask: A choice to protect patients in BC

Issue: BCMJ, Vol. 58, No. 10, December 2016, page(s) 555, 557 Point Counterpoint
Bonnie Henry, MD, FRCPC, Perry Kendall, OBC, MBBS, MSc, FRCPC

The BC health care worker influenza protection policy is an evidence-supported, systematically implemented, and ethically defensible program that has successfully improved influenza vaccine coverage among health care workers in the province and, as a result, improved protection for our vulnerable patients. In response to Mr Offley’s critique of the policy, we present the following evidence.

First, the policy is supported by the majority of health care workers in BC, according to a recent survey, and has been upheld as reasonable at arbitration in BC.[1]

The policy is, in fact, predicated on several factors:
•    The universal recommendation that health care workers receive annual vaccination against influenza.[2,3]
•    The failure in Canada of voluntary programs to achieve anything close to high coverage levels.[4]
•    The evidence that high vaccine coverage provides patient/resident protection.[5-9]
•    The fact that health care workers can and do transmit influenza to those they care for, and they do work while sick and may transmit influenza while asymptomatically shedding virus.[10]

The BC policy recognizes that health care workers have the right to refuse vaccination and provides them the option to wear surgical masks in patient care areas during influenza season when influenza is circulating in our communities. There is evidence that masking will reduce influenza virus transmission,[11-22] and while the body of evidence is not as robust as that supporting influenza immunization, it is at least as strong as that supporting hand washing in the prevention of nosocomial transmission. Where evidence is lacking (as described in testimony to the arbitrator in Ontario that Mr Offley quotes) is on the issue of whether there is any additional benefit to an individual wearing a mask over and above immunization.

It is recognized that the current technology for making influenza vaccines produces less than optimal effective antigens. The continuing annual drift in viral antigens is challenging and does result in varying degrees of protection from year to year (from the low of 13% in 2014–15 to over 80% in 2010–11 in Canada with an accepted average of 60% protection over many seasons).[23,24] Nonetheless the great majority of infectious disease specialists and influenza experts continue to recommend that people get vaccinated against influenza if they are at higher risk of severe influenza or complications from influenza or if they are in contact with higher-risk individuals.

While a universal vaccination and mask policy might be the logical approach in the face of vaccine and circulating virus uncertainty, the BC policy seeks a balance of protection of the health care worker and the patient without posing undue hardship on health care workers. As Mr Offley observes, “masks are extremely uncomfortable to wear for 12 hours a day continuously over a 4-month period.”

Consistent application of the policy in BC has been recognized since its inception as a very important feature and considerable resources are spent on this. That some unvaccinated health care workers may seek to subvert the program by inferentially claiming vaccination status by not wearing a mask is regrettable, but fortunately it is not a characteristic of the overwhelming majority of our professionals.

Vaccinate or mask is a coherent policy based on the time-proven ethical principle primum non nocere (first, do no harm).

This article has been peer reviewed.

References Top

1.    Influenza control program policy grievance award. Vancouver: 2013. Accessed 19 May 2016. Archived by WebCite at
2.    National Advisory Committee on Immunization (NACI). Statement on seasonal influenza vaccine for 2015-2016. Public Health Agency of Canada, 2016.
3.    Talbot TR, Babcock H, Caplan AL, et al. Revised SHEA position paper: Influenza vaccination of healthcare personnel. Infect Control Hosp Epidemiol 2010;30:987-995.
4.    Lam P-P, Chambers LW, Pierrynowski MacDougall DM, et al. Seasonal influenza vaccination campaigns for health care personnel: Systematic review. CMAJ 2010;182:E542-E548. doi:10.1503/cmaj.091304.
5.    Potter J, Stott DJ, Roberts M, et al. Influenza vaccination of health care workers in long-term-care hospitals reduces the mortality of elderly patients. J Infect Dis 1997;175:1-6. doi:10.1093/infdis/175.1.1.
6.    Carman WF, Elder AG, Wallace LA, et al. Effects of influenza vaccination of health-care workers on mortality of elderly people in long-term care: A randomised controlled trial. Lancet 2000;355:93-97. doi:10.1016/S0140-6736(99)05190-9.
7.    Hayward AC, Harling R, Wetten S, et al. Effectiveness of an influenza vaccine programme for care home staff to prevent death, morbidity, and health service use among residents: Cluster randomised controlled trial. BMJ 2006;333:1241. doi:10.1136/bmj.39010.581354.55.
8.    Lemaitre M, Meret T, Rothan-Tondeur M, et al. Effect of influenza vaccination of nursing home staff on mortality of residents: A cluster-randomized trial. J Am Geriatr Soc 2009;57:1580-1586. doi:10.1111/j.1532-5415.2009.02402.x.
9.    Ahmed F, Lindley MC, Allred N, et al. Effect of influenza vaccination of health care personnel on morbidity and mortality among patients: Systematic review and grading of evidence. Clin Infec Dis 2014;58:50-57.
10.    Bryce E, Embree J, Evans G, et al. Mandatory influenza immunization of healthcare workers. Ottawa, ON: Association of Medical Microbiology and Infectious Disease Canada; 2012.
11.    Milton DK, Fabian MP, Cowling BJ, et al. Influenza virus aerosols in human exhaled breath: Particle size, culturability, and effect of surgical masks. PLoS Pathog 2013. Accessed 27 October 2016.
12.    Johnson DF, Druce JD, Birch C, et al. A quantitative assessment of the efficacy of surgical and N95 masks to filter influenza virus in patients with acute influenza infection. Clin Infect Dis 2009;49:275-277.
13.     Makison Booth C, Clayton M, Crook B, et al. Effectiveness of surgical masks against influenza bioaerosols. J Hosp Infect 2013;84:22-26.
14.    Mansour MM, Smaldone GC. Respiratory source control versus receiver protection: Impact of facemask fit. J Aerosol Med Pulm Drug Deliv 2013;26:131-137.
15.     Harnish DA, Heimbuch BK, Husband M, et al. Challenge of N95 filtering facepiece respirators with viable H1N1 influenza aerosols. Infect Control Hosp Epidemiol 2013;34:494-499.
16.    Loeb M, Dafoe N, Mahony J, et al. Surgical mask vs N95 respirator for preventing influenza among health care workers: A randomized trial. JAMA 2009;302:1865-1871.
17.    Cowling BJ, Chan KH, Fang VJ, et al. Facemasks and hand hygiene to prevent influenza transmission in households: A cluster randomized trial. Ann Intern Med 2009;151:437-446.
18.    Aiello AE, Perez V, Coulborn RM, et al. Facemasks, hand hygiene, and influenza among young adults: A randomized intervention trial. PLoS One 2012;7:e29744. doi: 10.1371/journal.pone.0029744.
19.     Simmerman JM, Suntarattiwong P, Levy J, et al. Findings from a household randomized controlled trial of hand washing and face masks to reduce influenza transmission in Bangkok, Thailand. Influenza Other Resp Viruses 2011;5:256-267.
20.    Suess T, Remschmidt C, Schink SB, et al. The role of facemasks and hand hygiene in the prevention of influenza transmission in households: Results from a cluster randomised trial; Berlin, Germany, 2009-2011. BMC Infect Dis 2012;12:26.
21.    Cowling BJ, Zhou Y, Ip DK, et al. Face masks to prevent transmission of influenza virus: A systematic review. Epidemiol Infect 2010;138:449-456.
22.    Bin-Reza F, Lopez Chavarrias V, Nicoll A, et al. The use of masks and respirators to prevent transmission of influenza: A systematic review of the scientific evidence. Influenza Other Resp Viruses 2012;6:257-267.
23.    Jefferson T, Di Pietrantonj C, Al-Ansary LA, et al. Vaccines for preventing influenza in the elderly. Cochrane Database Syst Rev 2010;17:CD004876. doi: 10.1002/14651858.CD004876.pub3.
24.    Osterholm MT, Kelley NS, Sommer A, et al. Efficacy and effectiveness of influenza vaccines: A systematic review and meta-analysis. Lancet Infect Dis 2012;12:36-44.

Dr Henry is Deputy Provincial Health Officer, British Columbia. Dr Perry Kendall is Provincial Health Officer, British Columbia.


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