Article
Influenza is a viral illness easily transmitted from person to person through air droplets passed by sneezing, coughing and a lack of adherence to appropriate handwashing guidelines.
Influenza tends to spread rapidly in seasonal epidemics. In temperate climates, epidemics usually occur during the autumn and winter months. Worldwide, annual epidemics result in 3–5 million cases of serious illness resulting in 250,000–500,000 deaths. At greatest risk of developing complications are adults >65 years of age, children <2 years and those with medical conditions that increase the likelihood of complications. Most influenza deaths occur in people >65 years old.
Vaccination is the principal measure for preventing influenza and reducing its impact. Safe and effective vaccines have been available for more than 60 years. Among healthy adults, influenza vaccines prevent 70–90% of influenza-specific illness. Among the elderly, vaccination can reduce severe illness and complications by up to 65% and deaths by 80%.
How well the influenza works (or its ability to prevent influenza illness) can range widely from season to season and can also vary depending on who is being vaccinated. At least two factors play an important role in determining influenza vaccine effectiveness – characteristics of the person being vaccinated (such as their age and health) and the similarity or ‘match’ between the influenza viruses in the vaccine and those spreading in the community. The most common side-effects of the injectable (inactivated) influenza vaccine include soreness, redness or swelling at the site of the injection. These reactions are temporary and occur in 15–20% of recipients.
Unlike other prophylaxis measures, such as hepatitis B vaccination, influenza vaccination rates among healthcare workers (HCWs) are low. The CDC have recommended vaccination for more than 20 years. Yet, the rates for US HCWs in the past have ranged from 45–65%. Despite recommendations by the Department of Health, in the UK during 2010–2011 the influenza vaccination rate among frontline HCWs was 35%.
Several cross-sectional studies examined the barriers to HCW influenza vaccination. Commonly cited reasons include:
HCWs are at an increased risk of acquiring influenza owing to their exposure to ill patients. Conversely, those patients who are at greatest risk of developing severe complications of influenza are themselves more likely to be exposed to potentially infectious HCWs. The virus can be transmitted to patients by both symptomatic and asymptomatic HCWs. Multiple studies show that 70% or more of HCWs continue to work, despite being ill with influenza, thus exposing patients to the virus.
The vaccine is most effective in younger, healthier individuals. Patients at highest risk, including the elderly and the immunocompromised, are least likely to develop an adequate response to the vaccine. Several studies demonstrated that HCW influenza vaccination reduces patient mortality. Vaccination appears to be an effective strategy for prevention.
Multi-faceted mandatory vaccination programmes have been implemented and found to be the single most effective strategy to increase HCW vaccination rates. Multiple facilities and systems achieved vaccination coverage of more than 95%. Institutions that have implemented a mandatory policy have dramatically reduced employee absenteeism as well as healthcare associated influenza, thereby improving patient safety and reducing healthcare costs.
Mandating facilities have made influenza vaccination ‘a condition for employment’, apart from medical exemptions (eg an allergy to eggs). Most locations offer religious exemptions, while some also allow declination for ‘personal reasons’. Some facilities also employ a different scheme – get vaccinated or wear a mask whenever treating patients.
A recent article discussed the issue well.1 The authors indicated that the vaccine was safe and effective and that there was an economic case for HCW vaccination. If vaccination does reduce risks/harm for patients, then there is also an ethical and legal argument. Vaccination is also a way to protect HCWs from occupational infections. The authors indicated that additional studies linking good strain match vaccines with the prevention of nosocomial infections in patients would offer further evidence. It may therefore be considered that the Department of Health in England should move from its current position of strongly recommending to making influenza vaccination mandatory for HCWs with direct patient contact.