Table 5.
Rapid Evidence Appraisal summary of findings table for all questions.
| Review Question | # of individual studies included by question | # of Higher Quality studies (Maryland Quality Score ≥ 4) | Settings Populations or# of studies included | Main findings | Limitations of included studies | Future Considerations |
|---|---|---|---|---|---|---|
|
Topic 1 Question 1 Are HWs at an increased risk of influenza infection? |
7 | 1 study A Comprehensive review which evaluates systematic reviews addressing this question. |
-Hospital settings with different occupations such as physicians, nurses, close patient contact or less patient -H1N1 risk and Seasonal influenza risk -Patients and HWs during outbreaks |
-Yes, in some cases, HWs are at an increased risk, but not always -H1N1pdm09 risk to HWs is clearer than seasonal influenza -Risk can vary by occupation with H1N1pdm09 but unclear for seasonal influenza -Influenza risk appears to vary year to year depending on virus circulation --Difficult to look across multiple studies to draw conclusions unless controlling for study year, circulating virus, patient populations, health worker type or occupation |
--Pooled data may lead to inaccurate conclusions -Publication and selection Bias -Use of indirect measures of influenza -Use of seasonal influenza elements for pandemic models |
-Research to validate variability in risk with influenza by year, virus, occupation, setting, patient populations - Consideration of this variability in risk as an inherent part of research or policy development |
|
Topic 1 Question 2 Does influenza vaccination benefit HWs or their employers? |
14 | 4 studies 2 reviews, 2 RCTs |
-Hospital settings -University medical centres -Staff and students of Dental Faculty -Trivalent vaccine -H1N1pdm09 vaccine |
-Yes, vaccine can be cost-saving and reduce influenza burden, but it isn’t entirely consistent -Several higher-level studies suggest vaccine efficacy in health workers and cost-savings to employers through reduced absenteeism -We identified a total of 5 RCTs to answer this question, 2 not part of recent systematic reviews and had conflicting results -One RCT during 2009–2011 found vaccination to increase absenteeism -One RCT only used ILI as an outcome measure -Vaccine benefit may be greater when considering asymptomatic influenza and the possible impact on transmission |
-Applying vaccine effectiveness, efficacy, or attack rate of healthy adults to HWs. -Self-reported outcomes -Non-specific outcomes -low circulation of virus confounds vaccine effectiveness |
-A need for updated high quality RCTs assessing vaccine benefit over time in multiple settings. --Develop research standards for influenza vaccine benefit --Vaccine type may vary findings |
|
Topic 2 Question 1 Do HWs transmit influenza to patients? |
11 | 1 study Using high resolution contact data detected with sensors |
-Patients and HWs in Elderly care Hospital Wards -In HIV + patients, --In children During Nosocomial outbreaks |
-Yes, HWs have been implicated in some transmission events, most frequently among elderly patients -Transmission and introduction can be directly linked to HWs, patients, and community/visitors- |
-Small sample size in many studies -Most studies of moderate quality |
-Need to better understand the role of asymptomatic infections in transmission -Transmission reduction measures need to consider HWs, patients, and outside contacts as a continuum -Need larger studies over a longer duration using high-resolution contact data |
|
Topic 2 Question 2 Part A Does influenza vaccination in HWs benefit patients |
6 | 2 | -Long-term care facilities in patients -Acute Care facilities -Internal Medicine -Pediatrics |
-Maybe - evidence continues to suggest a benefit on protection against all-cause mortality to LTCF patients -Evidence is mixed in other populations, but one RCT in the Netherlands suggests a reduction in nosocomial infection in internal medicine wards, not pediatrics -Very few newer RCTs evaluating patient benefit -Several studies evaluate ILI rather than lab-confirmed as a measure of benefit |
-Decisions based on 4 highly biased RCTs in long-term care facilities due to attrition rate, no blinding, contamination in control groups, low rates of vaccination coverage | -Need updated cRCTs which span years -Need standardized approaches/population to answering this question -Patient benefit variations need to be understood and appreciated (more benefit to more vulnerable patients) |
|
Topic 2 question 2 Part B How many HWs need to be vaccinated (NNV) to ensure a benefit to patients? |
6 | 0 | -Long term care facilities -Medical Centre hospital -Tertiary Hospital |
-NNV range from 3 to 50 -Appears to be a benefit in LTCFs when 100% of HWs are vaccinated with the possible prevention of 60% of infections -Appears to be a proportional benefit with a greater reduction in nosocomial transmission with higher coverage -Appears to be a curvilinear relationship between rising coverage and reduction in nosocomial infections that can be impacted by visitors or other contact elements |
-Vaccine effectiveness for HWs based on that for healthy adults -Other assumptions in models may lead to inaccurate conclusions -Outcome definitions in models significantly impacted whether herd immunity could be induced |
-NNV estimates need to factor in differences in outcome measures used -Need to expand body of knowledge beyond geriatric populations which may skew the total findings -Need to develop HW vaccine efficacy and attack rate standards for models |
|
Topic 3 Question 1 What are the successful and practical interventions which increase HW influenza vaccine uptake? |
10 | 8 | -Primary care community clinics -Acute care hospital staff -HWs in tertiary hospitals -HWs with and w/o patient contact -All personnel of a health institution |
-Mandatory Vaccination to be able to work remains the most successful intervention to increase uptake -Other successful interventions are:
|
Publication bias considering studies that were not effective may not be published -Selection bias as some may not have reported baseline vaccine uptake before intervention -Lack of blinding in RCTs -Hard to separate the benefit of one intervention as distinct from the others when a part of multi-faceted interventions |
-Clear guidance needed on vaccine program implementation in HWs which clarify the options of mandatory policy options vs. other. -Develop a standardized checklist of components critical for vaccine uptake success - Develop guidance on how to develop targeted interventions catering to the individual context for implementation |
|
Topic 3 Question 2 What are the sociological, behavioural, and public health policy aspects of influenza vaccine uptake in HWs? |
3 | 3 | -Long-term care facilities - Mixed hospital settings of HWs -Mixed outpatient settings of HWs |
-Strongest barriers to uptake were HW’s lack of confidence about disease severity or vaccine effectiveness and a lack of professional or ethical obligation to get vaccinated. -Strongest reason to vaccinate was to protect oneself and not patients -Success of a vaccination program may be influenced by the complex relationship between HWs and the organization and management of the health care system within which they work. -Ecological model shows promise an alternate to the widely used health belief model |
-Limited use of models other than Health Beliefs Model | -Greater diversity of study approaches to reframe issues through alternative lenses -Need to integrate HW influenza vaccine programs into existing programs to ensure long term -Need to expand discussion on the importance of top-down support for vaccine programs in HWs to develop a culture of vaccination -Need to have a better understanding of the influenza of management /organizationl structures where implementation will take place |