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. 2022 Dec 9;14(12):2746.
doi: 10.3390/v14122746.

Changes following the Onset of the COVID-19 Pandemic in the Burden of Hospitalization for Respiratory Syncytial Virus Acute Lower Respiratory Infection in Children under Two Years: A Retrospective Study from Croatia

Dina Mrcela  1 , Josko Markic  1   2 , Chenkai Zhao  3 , Daniela Veljacic Viskovic  2 , Petra Milic  2 , Roko Copac  4 , You Li  3
Affiliations

Changes following the Onset of the COVID-19 Pandemic in the Burden of Hospitalization for Respiratory Syncytial Virus Acute Lower Respiratory Infection in Children under Two Years: A Retrospective Study from Croatia

Dina Mrcela et al. Viruses. .

Abstract

To understand the changes in RSV hospitalization burden in children younger than two years following the onset of the COVID-19 pandemic, we reviewed hospital records of children with acute lower respiratory infection (ALRI) between January 2018 and June 2022 in Split-Dalmatia County, Croatia. We compared RSV activity, age-specific annualized hospitalization rate, and disease severity between pre-COVID-19 and COVID-19 periods. A total of 942 ALRI hospital admissions were included. RSV activity remained low for the typical RSV epidemic during 2020-2021 winter. An out-of-season RSV resurgence was observed in late spring and summer of 2021. Before the COVID-19 pandemic, the annualized hospitalization rate for RSV-associated ALRI was 13.84/1000 (95% CI: 12.11-15.76) and highest among infants under six months. After the resurgence of RSV in the second half of 2021, the annualized hospitalization rate for RSV-associated ALRI in children younger than two years returned to the pre-pandemic levels with similar age distribution but a statistically higher proportion of severe cases. RSV immunization programs targeting protection of infants under six months of age are expected to remain impactful, although the optimal timing of administration would depend on RSV seasonality that has not yet been established in the study setting since the onset of the COVID-19 pandemic.

Keywords: COVID-19; bronchiolitis; children; respiratory syncytial virus; severity.

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Conflict of interest statement

YL reports grants from Wellcome Trust outside the submitted work. Other authors declare that they have no conflict of interest.

Figures

Figure 1
Figure 1
Timeline of implementation and relaxation of non-pharmaceutical interventions in response to the COVID-19 pandemic in Croatia. Five categories of non-pharmaceutical interventions were summarized: education, mobility, work, physical gathering, and hygiene from 16 Mar 2020 to 4 April 2022. Black vertical line indicates when lockdown was in Croatia on 16 March 2020. * Total border closure. † Closure of public spaces. ‡ Restaurants and cultural institutions closure. § Ban on holding all public events. fI Ban on gathering >5 persons in one place. ¶ Ban on gathering >10 persons in one place.
Figure 2
Figure 2
Month-by-month distribution of hospitalizations due to all-cause (panel A) and RSV-associated (panel B) ALRI. Black line: Number of hospitalizations. Red vertical line: Lockdown in Croatia on 16 Mar 2020.
Figure 3
Figure 3
Change in 12-month hospitalization rates (per 1000) of all-cause and RSV-associated ALRI by age group, before and after the onset of the COVID-19 pandemic. (A) 12-month all-cause ALRI moving average hospitalization rate. (B) 12-month RSV-associated ALRI moving average hospitalization rate. Black arrows denote the time interval used for calculating the 12-month hospitalization rates. Red vertical line: lockdown in Croatia on 16 Mar 2020.
See this image and copyright information in PMC

References

    1. McAllister D.A., Liu L., Shi T., Chu Y., Reed C., Burrows J., Adeloye D., Rudan I., Black R.E., Campbell H., et al. Global, Regional, and National Estimates of Pneumonia Morbidity and Mortality in Children Younger than 5 Years between 2000 and 2015: A Systematic Analysis. Lancet Glob. Health. 2019;7:e47–e57. doi: 10.1016/S2214-109X(18)30408-X. - DOI - PMC - PubMed
    1. Mulholland K. Global Burden of Acute Respiratory Infections in Children: Implications for Interventions. Pediatr. Pulmonol. 2003;36:469–474. doi: 10.1002/ppul.10344. - DOI - PubMed
    1. O’Brien K.L., Baggett H.C., Brooks W.A., Feikin D.R., Hammitt L.L., Higdon M.M., Howie S.R.C., Deloria Knoll M., Kotloff K.L., Levine O.S., et al. Causes of Severe Pneumonia Requiring Hospital Admission in Children without HIV Infection from Africa and Asia: The PERCH Multi-Country Case-Control Study. Lancet. 2019;394:757–779. doi: 10.1016/S0140-6736(19)30721-4. - DOI - PMC - PubMed
    1. Li Y., Wang X., Blau D.M., Caballero M.T., Feikin D.R., Gill C.J., Madhi S.A., Omer S.B., Simões E.A.F., Campbell H., et al. Global, Regional, and National Disease Burden Estimates of Acute Lower Respiratory Infections Due to Respiratory Syncytial Virus in Children Younger than 5 Years in 2019: A Systematic Analysis. Lancet. 2022;399:2047–2064. doi: 10.1016/S0140-6736(22)00478-0. - DOI - PMC - PubMed
    1. Borchers A.T., Chang C., Gershwin M.E., Gershwin L.J. Respiratory Syncytial Virus—A Comprehensive Review. Clin. Rev. Allergy Immunol. 2013;45:331–379. doi: 10.1007/s12016-013-8368-9. - DOI - PMC - PubMed

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