Common seasonal respiratory virus infections in allogeneic stem cell transplant recipients during the SARS-COV-2 pandemic

Abstract

The SARS-COV-2 pandemic has led to strict and generalized transmission prevention measures that may have changed the epidemiological landscape of common seasonal respiratory virus (CSRV). Through a prospective CSRV survey program conducted from 2016 onwards in allogeneic stem cell transplant (allo-HSCT) recipients with respiratory symptoms, we aimed to analyze and compare the epidemiology and characteristics of CSRV over three consecutive periods [from February 1 to September 30 of 2018 (P1), 2019 (P2), and 2020 (P3)]. CSRV screening was performed through multiplex PCR assays during the study period. We identified 188 consecutive allo-HSCT recipients with 406 episodes screened for CSRV during the study period, of which 147 developed 300 CSRV. In P1 and P2 we diagnosed 115 (38.3%) and 145 (48.3%) CSRV episodes, respectively, whereas in P3 only 40 (13.3%) episodes were detected ( p < 0.001). During P3, we observed a reduction of 80.2% in Ev/Rh, 93.3% in RSV, 80% in hIV, 96.3% HPIV, 68.4% in hMPV, 77.7% in ADV, 100% in HBoV, and 53.6% in HCoV as compared to P1 and P2. Consequently, we also observed a decline in absolute numbers of lower respiratory tract disease (68.1%), co-infections (91.7%), and hospitalizations (72.6%) during P3. We diagnosed SARS-COV-2 in nine allo-HSCT recipients, representing 23% of all CSRV detections in that period. In conclusion, we provide evidence of a significant drop in CSRV circulation during the SARS-COV-2 pandemic in our allo-HSCT recipients, indicating that prevention measures in the general population are highly effective in reducing CSRV prevalence and its complications in immunocompromised patients.

One-year breakthrough SARS-CoV-2 infection and correlates of protection in fully vaccinated hematological patients

“…It looks suitable that such measures would be applied not only to immunosuppressed patients and their caregivers but also to those who have a close contact with these patients (friends, other relatives, health staff, etc). We already learned that the more thorough preventive transmission measures are, the lesser the incidence of respiratory virus infections in immunocompromised patients [ 22 ].…”

SARS-CoV-2 vaccine response and rate of breakthrough infection in patients with hematological disorders

“…are still highly recommended. However, the largest reduction in the incidence of respiratory virus infections in immunocompromised patients has been observed when preventive transmission measures have been instituted globally [ 39 ] as compared to when such measures are applied only to immunosuppressed patients and their caregivers; in fact, in these latter scenarios the time of onset and incidence of different respiratory virus infections (including SARS-CoV-2) in HSCT recipients strongly mirror those in the patients’ communities [ 1 , 19 ].…”

Respiratory virus infections after allogeneic stem cell transplantation: Current understanding, knowledge gaps, and recent advances

“…Prospective studies from Seattle (US) and Valencia (Spain) have ranked pre‐pandemic CARVs in decreasing order as follows: human rhinovirus (HRV), hCoV, respiratory syncytial virus (RSV), human parainfluenza virus (hPIV), IFV, HMPV, and lastly human bocavirus (hBoV) and adenovirus (Adv) 16,17 . However, during the COVID‐19 pandemic there was a clear predominance of SARS‐CoV‐2, 5 so the true ranking after the pandemic remains to be determined. Of note, multiple CARV co‐infections are characteristic in the allo‐HCT setting (19% to 38%), 16,17 possibly related to both the seasonal overlap in circulation of different CARV types in the community 18 and/or the concurrence of extended viral shedding from a prior episode with a new CARV infectious episode.…”

“…Even before the pandemic, CARV infections were known to pose a greater risk of morbidity and mortality for allo-HCT recipients, 1 and this has been further confirmed with SARS-CoV-2 infections. 2 Although currently circulating again in the community and infecting HSCT recipients, 3 during the 3-year pandemic CARV circulation was negligi-ble among hematological patients, 4 particularly allo-HCT recipients, 5 raising concerns about the potential loss of annual immunity booster provided by prior-season CARV infections in this population. SARS-…”