Published online Jul 24, 2022. doi: 10.5306/wjco.v13.i7.609
Peer-review started: February 8, 2022
First decision: June 7, 2022
Revised: June 15, 2022
Accepted: July 6, 2022
Article in press: July 6, 2022
Published online: July 24, 2022
Processing time: 164 Days and 6.8 Hours
It has been theorized that 75%-80% of febrile neutropenia (FN) is caused by endogenous pathogens, while up to 20% of cases are thought to be caused by a viral infection. It is unknown if precautions such as masking and social distancing reduce the risk of FN in susceptible populations.
To determine whether coronavirus disease 2019 (COVID-19) infection mitigation efforts, namely masking and social distancing, were associated with a reduction in the incidence of FN.
This was a retrospective population based cohort study comparing the incidence of FN in the 13 mo prior to (Year 0) and 13 mo following (Year 1) the public health executive orders (PHEO) in Michigan. Data was queried for all emergency department (ED) visits from April 1, 2019 to March 31, 2021 from the National Syndromic Surveillance Program, a program which collects data that is voluntarily submitted by approximately 89% of Michigan EDs. The primary study outcome was the incidence of FN as a proportion of ED visits in the 13-mo before and 13-mo after COVID-19 mitigations efforts, namely masking and social distancing. We hypothesized that there would be a significant decrease in the incidence of FN in the period following the PHEO aimed at reducing the spread of the severe acute respiratory syndrome coronavirus 2 virus.
There was a total of 8979221 total ED visits captured during the study period. In Year 0 there were 5073081 recorded ED visits and 3906140 in Year 1. There was a significant reduction in the proportion of total ED visits with a diagnosis of FN, decreasing 13.3% across periods (0.15% vs 0.13%, P = 0.036). In patients with a hematologic malignancy a more impressive reduction in the incidence of FN was evident following PHEO (22% vs 17%, P = 0.02).
We found a significant association between social distancing and mask guidelines implemented on a large public scale with decreased rates of FN, particularly in those with a hematologic malignancy. These findings may be useful in the design of future research and recommendations regarding the prevention of FN.
Core Tip: There has been a proven reduction in respiratory viral infections (e.g., flu, common cold, etc.) with the implementation of social distancing and masking during coronavirus disease 2019 mitigation efforts. It has been theorized that up to 20% of febrile neutropenia is caused by viral infections. We found a significant reduction in the incidence of febrile neutropenia following the implementation of public health interventions, namely masking and social distancing, with the overall incidence of febrile neutropenia decreasing by approximately 13%. The largest reduction in febrile neutropenia was found for hematologic malignancies where the incidence of febrile neutropenia declined by 22%.