An evaluation of the incidence and absenteeism rates of health care workers reporting flu-related illnesses at an academic hospital in the Western Cape: a retrospective cohort study
Date
2017-12
Authors
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Publisher
Stellenbosch : Stellenbosch University
Abstract
ENGLISH SUMMARY : Introduction: Seasonal Influenza -related illnesses impose a heavy burden on society. Vaccination programmes are the most effective strategy for preventing the illnesses and have been recommended for certain high- risk groups. Healthcare workers involved in the care of these vulnerable patients may be infected clinically or sub-clinically with Influenza. They are therefore urged to accept influenza vaccination as part of the broader control of Influenza policy. This study evaluates the willingness of uptake and the impact that influenza vaccination campaigns might have among healthcare workers in a tertiary health setting.
Objective: To determine the proportion of voluntary vaccine uptake among healthcare workers as well as describing any potential differences between this vaccinated population and their randomly selected unvaccinated controls.
Methods: A retrospective cohort study investigating the incidence of flu and its related illnesses, including its impact on absenteeism rates in the seasonal flu years of 2013 and 2014.
The study setting was Tygerberg Academic Hospital, Parow, Western Cape. All vaccinated employees during the study period were compared to matched unvaccinated controls in a 1:2 ratio. Employees who got ill during the study period were sourced from the facility’s Human Resource database. Illness incidence and absenteeism rates were extracted from this outcome database and analysed to determine trends between study arms as well as between occupational categories.
Results: A total of 4.6% and 2.8% of employees accepted vaccination for the seasonal flu years of the 2013 and 2014 respectively. The study population was 1020 with 340 healthcare workers in the exposed arm. Overall, there were more employees that fell ill compared to those that remained healthy during the study period (700 vs 320). For all instances of Influenza and related illnesses (clinically specified) illnesses, there was no statistically significant difference between the vaccinated and unvaccinated study groups [RR 1.06, 95% CI (0.87- 1.28), p=0.28]. The frequency of illness in the vaccinated was less than that observed in the controls (79 vs 164, z-score=2.04 p-value= 0.041). About 60% of all sick leaves had no clinically specified diagnosis while the incidence of clinically specified illnesses was 32.65% among the vaccinated and 30.88% in the control group. This therefore placed the true incidence rate of influenza-related illnesses between 32,647 to 69,706 /100,000 population per year in the vaccinated and 30,882 to 68,088 /100,000 population per year in the unvaccinated.
Conclusion: There was very low response to calls for influenza vaccination despite unexpected high reports of influenza-related illnesses in our study setting. Among healthcare workers, a higher proportion reported illness incidents and consequently had higher absenteeism rates compared to those that remained healthy during the study duration. These variables did not differ based on vaccination status perhaps due to the low acceptance rate. Healthcare workers are encouraged to partake in the seasonal flu vaccinations to minimise influenza transmission risks to vulnerable patients.
AFRIKAANSE OPSOMMING : Geen opsomming beskikbaar.
AFRIKAANSE OPSOMMING : Geen opsomming beskikbaar.
Description
Thesis (MOccTher)--Stellenbosch University, 2017.
Keywords
Influenza vaccines -- Western Cape (South Africa), Medical personnel -- Western Cape (South Africa), Cohort study, UCTD