Health care personnel (HCP) frequently had acute respiratory illnesses (ARI) during the influenza seasons between 2016 and 2019; they were also infrequently vaccinated against influenza and often used antibiotics rather than antivirals to treat their illnesses, according to study findings published in Influenza and Other Respiratory Viruses.
Researchers conducted a prospective cohort study to quantify the incidence of ARI and influenza among HCP from 5 hospitals in Lima, Peru. The researchers also characterized symptoms, absenteeism, and the use of medications for these illnesses among study participants.
The study sample included adult participants of both sexes from a range of HCP groups (ie, physicians, nurses, technicians, and assistants). All HCP in the study had hands-on or face-to-face contact with patients in regular shifts, worked at least 30 hours per week, and were employed for at least 1 year. They also completed an enrollment survey soliciting demographic data as well as information on their vaccination status and well-being/illness status, the types of patients they saw, and their use of personal protective equipment.
The researchers conducted ongoing surveillance of all participants (via twice-weekly messages asking about potential ARI symptoms) and took pre- and post-influenza-season sera from all participants. An ARI was defined as at least 1 incidence of acute cough, runny nose, body aches, or feverishness. HCP with ARI provided nasal swabs for reverse-transcription polymerase chain reaction (rt-PCR) testing for influenza RNA.
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Our findings suggest the need for continuing medical education about the risk of influenza and benefits of vaccination and stay-at-home-while-ill policies.
A total of 2968 HCP contributed person time (total, 2605.2 person-years [PY]) information; of those, 657 HCP participated in 1 study year, 783 in 2 years, 923 in 3 years, and 605 in all 4 years. Their median age was 41 years (interquartile range [IQR], 32-51), and 72% were female. Among the HCP, 1412 (49%) were vaccinated against influenza at least once from 2016 to 2019, and 36 (6%) of the HCPs who participated in all 4 years were vaccinated every year.
The 2968 HCP had 5750 ARI and provided 3054 respiratory swabs. The HCPs had a median of 1 ARI (IQR, 0-3) and 15 ARI illness-days (IQR, 7-29 days). Of the group, 143 HCP had 1 rt-PCR-confirmed influenza ARI event and 2 had 2 rt-PCR-confirmed influenza events (147 total ARI from 2016-2019). Among this group of 147, 37 HCPs (25%) were vaccinated. The median duration of influenza illnesses was 8 days (IQR, 6-11 days), and HCP with laboratory-confirmed influenza were present at work while ill for 1187 hours.
A sample of 699 ARIs that tested negative for influenza were reflex-tested, of which 185 (26%) were positive for rhinoviruses or enteroviruses, 76 (11%) for seasonal coronaviruses (ie, 40 [6%] for OC43, 17 [2%] for NL63, 12 [2%] for HKU1, and 7 [1%] for 229E), 11 (2%) for respiratory syncytial virus, and 9 (1%) for metapneumovirus.
The most common symptoms in the 147 rt-PCR-confirmed influenza cases were rhinorrhea (94%), cough (82%), and myalgia (80%), and 71% of those HCP took medications, including antipyretics (46%) and antibiotics (37%), with 1 participant (0.7%) taking antivirals.
The ARI incidence rate was 218/100 PY, and the age, sex, and occupation-weighted influenza-associated ARI was 10.0/100 PY. When pre- and post-season sera were analyzed, 19.1% (95% CI, 17.2%-21.1%) of asymptomatic and unvaccinated HCP had influenza antibodies at the end the influenza epidemics.
In multivariable modeling, ARI risk was significantly increased in female HCPs (adjusted relative rate [aRR], 1.1; 95% CI, 1.05-1.25) vs male HCPs.
HCP who wore a well-fitting mask and goggles during aerosolizing procedures had a significantly decreased risk of ARI (aRR, 0.8; 95% CI, 0.68-0.94) compared with those who did not.
Study limitations include the reliance on enrollment surveys for HCP characteristics. Also, cohort size, identification of ARI, respiratory swabbing, the ability to laboratory-confirm influenza, and confidence in year-specific ARI and seroconversion rates varied in each influenza season.
“HCP were frequently ill and often worked rather than stayed at home while ill,” said the study authors. “Our findings suggest the need for continuing medical education about the risk of influenza and benefits of vaccination and stay-at-home-while-ill policies.”
