A surge in respiratory syncytial virus infection-related hospitalizations associated with the COVID-19 pandemic: An observational study at pediatric emergency referral hospitals in Tokushima Prefecture

doi:10.21203/rs.3.rs-2433404/v1

Download PDF

Research Article

A surge in respiratory syncytial virus infection-related hospitalizations associated with the COVID-19 pandemic: An observational study at pediatric emergency referral hospitals in Tokushima Prefecture

https://doi.org/10.21203/rs.3.rs-2433404/v1

This work is licensed under a CC BY 4.0 License

Version 1

posted

You are reading this latest preprint version

Purpose

The outbreak of coronavirus disease (COVID-19) resulted in implementation of social distancing and other public health measures to control the spread of infection and improve prevention, resulting in a decrease in respiratory syncytial virus (RSV) and pediatric respiratory tract infection rates. However, there was a rapid and large re-emergence of RSV infection in Japan. Notably, we were faced with a difficult situation wherein there was a shortage of hospital beds. This study aimed to examine the epidemiological patterns of RSV-related hospitalizations among children before and after the COVID-19 pandemic onset at two pediatric emergency referral hospitals covering the entire Tokushima Prefecture.

Methods

Data were extracted from electronic medical records of children hospitalized with RSV infection between January 1, 2018, and December 31, 2021. All patients meeting the eligibility criteria were included in this study. The rates of study outcomes were documented annually during 2018–2021 and compared between the 2018–2020 and 2021 periods.

Results

In 2020, there was no RSV infection outbreak. In contrast, in 2021, RSV infection rate peaks were observed 1–2 months earlier than those in the previous years. Hospitalizations at the peak week in 2021 were 2.2- and 2.8-fold higher than those in 2018 and 2019, respectively. Hospitalizations in 2021 were concentrated within a short period. In addition, there was a significant increase in hospitalizations among children aged 3–5 months and those older than 24 months. Hospitalizations of children with siblings at home increased. The high-flow nasal cannula (HFNC) use rate nearly doubled in 2021.

Conclusions

A new pandemic in the future may cause an outbreak of RSV infection that can result in an intensive increase in the number of hospitalizations of pediatric patients requiring respiratory support, especially in infants aged < 6 months. There is an urgent need to improve the preparedness of medical systems, particularly in terms of the number of inpatient beds and the immediate availability of HFNC.

respiratory syncytial virus

coronavirus disease

high-flow nasal cannula

pediatric emergency referral hospital

sibling

Public health measures introduced to control the spread of coronavirus disease influenced other infectious disease outbreaks.
Although previously suppressed worldwide, a re-emergence of respiratory syncytial virus (RSV) infections was reported, and a major RSV outbreak was detected in Japan in 2021.

What is new

Compared to the previous years, the number of hospitalizations in 2021 was increased by 2.2–2.8-fold and concentrated within a short period.
There was an increase in hospitalizations of infants aged < 6 months with siblings at home and a significant increase in the use of high-flow nasal cannula during treatment.

The outbreak of coronavirus disease (COVID-19) resulted in the worldwide implementation of social distancing and other public health measures to control spread of infection and improve prevention of the disease. In Japan, the public was encouraged to adopt infection control measures, such as face mask use and hand washing, and avoid the “three Cs” (closed spaces, crowded places, and cross-contact settings) via physical distancing [1]. These measures resulted in a decrease in the rates of pediatric respiratory infections, including respiratory syncytial virus (RSV) infections [2]. RSV infections affect children aged < 2 years and can cause severe disease in infants aged < 6 months [3]. There were an estimated 33 million cases of RSV-associated lower respiratory tract infections among children aged 0–60 months worldwide in 2019, including 3.6 million hospitalizations and 26,300 deaths [4].

Following the relaxation of COVID-19 measures, a re-emergence of RSV infections was observed worldwide [5–8]. In contrast, even in Japan, where infection control measures continue, the number of cases has increased nationwide since March 2021, with incidence rates peaking in July [9], including in Tokushima Prefecture [10]. At our hospitals, the number of hospitalized RSV infection patients increased massively. We were faced with a difficult situation wherein there was a shortage of hospital beds and high-flow nasal cannulas (HFNCs). The major change in the epidemiological pattern of RSV infection transmission observed in 2021, compared with that in previous years, was the increase in the age at infection among children, with those aged ≥ 2 years being more susceptible to infection [11]. However, it has not been well investigated whether infection numbers and severity, as well as age at infection, have changed and how these changes have impacted medical care for hospitalized children.

This study aimed to compare the patterns of pediatric RSV-related hospitalizations between the period before and after the onset of the COVID-19 pandemic at two pediatric emergency referral hospitals in Tokushima Prefecture. These two hospitals provide pediatric care for the entire Tokushima Prefecture; therefore, the presented findings on RSV hospitalizations can be considered to provide an overall representation of the region.

Study design and patients

We conducted a retrospective observational study of all pediatric patients admitted to the two referral hospitals in Tokushima Prefecture; data were extracted from electronic medical records of children hospitalized with RSV infection before and after the onset of the COVID-19 pandemic. Children who were admitted to the Department of Pediatrics at Tokushima Prefectural Central Hospital and the Department of Pediatrics at Tokushima Red Cross Hospital, in Tokushima Prefecture, Japan, between January 1, 2018, and December 31, 2021, and who met all the following eligibility criteria were included in this study: positive results on a rapid diagnostic test or clinical diagnosis of RSV infection by a physician; entry in the electronic medical record as any of the following – “RSV infection,” “RSV bronchiolitis,” “RSV pneumonia,” and “RSV encephalopathy”; and treated on site during the study period, as evidenced by medical records. We excluded cases mentioned as RSV disease but were identified as not having RSV infection in the medical record.

Data source and collection

The study period overlapped with the change in pediatric emergency medical care system schedules of the hospitals. Both participating hospitals had a 24-hour operating pediatric care system that accepted secondary and tertiary emergency patients after hours from 17:00 to 8:30 the following day, as well as primary emergency patients from 22:30 to 8:30 the following day. However, in November 2019, owing to a shortage of pediatricians, the two hospitals introduced a rotating system for providing out-of-hours pediatric emergency care. In July 2020, the Tokushima Prefectural Central Hospital resumed the previous 24-hour emergency care system. During the period of the present analysis (2018–2021), only these two hospitals in Tokushima Prefecture provided out-of-hours emergency care and pediatric emergency hospitalization. Therefore, the data obtained from the participating hospitals represent all RSV infection cases recorded during the study period in this area.

Data on the following variables were extracted from the databases of the participating hospitals: number of children hospitalized for RSV infection per week; patient characteristics, including age (months), sex, palivizumab indication, palivizumab prophylaxis, presence of siblings; hospitalization duration (days), oxygen use rate (%, [number of children on oxygen/number of hospitalized children] ⋅ 100); HFNC use rate ([HFNC children/admitted children] ⋅ 100); ventilator use rate (%, [number of ventilator-controlled children/number of hospitalized children] ⋅ 100); and mortality rate ([number of deaths/number of hospitalized children] ⋅ 100).

Palivizumab indications included: infants aged ≤ 12 months with a gestational age at birth of ≤ 28 weeks; infants aged ≤ 6 months with a gestational age at birth of 29–35 weeks; infants aged ≤ 24 months who had been treated for bronchopulmonary dysplasia within the previous 6 months; infants aged ≤ 24 months with congenital heart disease, immunodeficiency, and/or Down syndrome.

Data analysis

The rates of study outcomes were considered annually during 2018–2021 and were compared between 2018–2020 and 2021. If there was an increase in hospitalization frequency in any age group, we conducted age-stratified analyses. All statistical analyses were performed with EZR (Version 1.40, Saitama Medical Center, Jichi Medical University, Saitama, Japan) [12], which is a graphical user interface for R (The R Foundation for Statistical Computing, Vienna, Austria). More precisely, it is a modified version of R commander designed to add statistical functions frequently used in biostatistics. The Mann–Whitney U test was used to compare age differences. The Welch t-test was used to compare hospitalization duration. The Pearson chi-square test was used for all other comparisons. P-values < 0.05 indicated a statistically significant difference.

In 2018, the number of children hospitalized with RSV infection peaked at week 35 (27 August to 2 September), with 23 new hospitalizations/week (Fig. 1). In 2019, the peak was at week 38 (16–22 September), with 18 new hospitalizations/week. In 2020, there were no infection peaks. In 2021, no hospitalizations were recorded before week 18; however, the number of hospitalizations peaked at week 30 (26 July to 1 August), with a rate of 50 hospitalizations/week; this represented 2.2- and 2.8-fold increases relative to values recorded in 2018 and 2019, respectively. To assess the degree of hospitalization during the epidemic, we examined the percentages of annual hospitalizations in the 3 weeks before and after the epidemic peak, which were 40.0% (107/267) in 2018, 29.8% (85/285) in 2019, and 86.3% (227/263) in 2021, indicating that significantly more hospitalizations were confined to a shorter period of time (both P < 0.001).

The annual number of hospitalizations was higher in 2018 (n = 267) and 2019 (n = 285) than in 2020 (n = 19) and comparable with that in 2021 (n = 263) (Table 1). The rates of hospitalizations among children aged < 6 months and ≥ 24 months increased in 2021 compared to those in 2018–2020; however, rates among children aged 6–23 months decreased in 2021. Specifically, there was a significant increase in the percentage of hospitalizations among children aged 3–5 months (11.6 vs. 16.7%; P < 0.05) and among those aged ≥ 24 months (14.9 vs. 24.7%; P < 0.001) in 2021. In contrast, the percentage of hospitalizations among children aged 12–23 months decreased in 2021 compared to 2018–2020 (31.7 vs. 19.0%; P < 0.001). There was no significant change in palivizumab indication (2.6 vs. 2.3%). Prophylaxis rates among palivizumab-eligible children were 70% (7/10) in 2018, 60% (3/5) in 2019, and 66% (2/3, excluding three cases with an unknown status) in 2021. Among children who had siblings at home, a greater proportion were hospitalized in 2021 than in 2018–2020 (56.9 vs. 71.1%; P < 0.05). The duration of hospitalization did not change (5.42 vs. 5.52 days). Oxygen use rates increased slightly (41.2 vs. 46.4%) and HFNC use rates increased significantly (7.7 vs. 13.7%; P < 0.01). Ventilator use rates were low in 2018–2020 (0.5%) and 2021 (1.1%). Only one RSV-related death was recorded in 2021, which was due to cardiopulmonary arrest on arrival.

Table 1

Annual changes in characteristics of children hospitalized with an RSV infection
	2018 (n = 267)	2019 (n = 285)	2020 (n = 19)	2021 (n = 263)	P-value
Age: months, n (%) < 3 months 3–5 months 6–11 months 12–23 months ≥ 24 months	77 (28.8) 30 (11.2) 39 (14.6) 87 (32.6) 34 (12.7)	70 (24.6) 33 (11.6) 45 (15.8) 89 (31.2) 48 (16.8)	3 (15.8) 3 (15.8) 5 (26.3) 5 (26.3) 3 (15.8)	73 (27.8) 44 (16.7) 31 (11.8) 50 (19.0) 65 (24.7)	0.674 0.0472 0.168 0.000123 0.000919
Sex: male, n (%)	153 (57.3)	153 (53.7)	10 (52.6)	142 (54.0)	0.765
Palivizumab indication n (%) no unknown	10 (3.7) 207 (77.5) 50 (18.7)	5 (1.8) 211 (74.0) 69 (24.2)	0 (0) 13 (68.4) 6 (31.6)	6 (2.3) 220 (83.7) 37 (14.1)	0.815
Palivizumab prophylaxis n (%) no unknown	7 (2.6) 210 (78.7) 50 (18.7)	3 (1.1) 213 (74.7) 69 (24.2)	0 (0) 13 (68.4) 6 (31.6)	2 (0.8) 221 (84.0) 40 (15.2)	0.354
Presence of siblings n (%) no unknown	151 (56.6) 45 (16.9) 71 (26.6)	164 (57.5) 44 (15.4) 77 (27.0)	10 (52.6) 4 (21.1) 5 (26.3)	187 (71.1) 31 (11.8) 45 (17.1)	0.0154
Hospitalization duration mean days (SD)	5.31 (1.97)	5.50 (2.17)	5.58 (1.61)	5.52 (2.50)	0.535
Oxygen use rate, n (%)	107 (40.1)	122 (42.8)	6 (31.6)	122 (46.4)	0.175
HFNC use rate, n (%)	17 (6.4)	25 (8.8)	2 (10.5)	36 (13.7)	0.00784
Ventilator use rate, n (%)	2 (0.7)	1 (0.4)	0 (0)	3 (1.1)	0.386
Mortality rate, n (%)	0 (0)	0 (0)	0 (0)	1 (0.4)	NA

HFNC, high-flow nasal cannula; RSV, respiratory syncytial virus; SD, standard deviation

Increases in hospitalizations among children aged < 6 months and ≥ 24 months were examined separately. Among infants aged < 6 months, there was a significant increase in hospitalizations among those who had siblings at home in 2021 (74.1% vs. 94.0%; P < 0.01) (Table 2). The use of HFNC also increased significantly in 2021 (16.7% vs. 26.5%; P < 0.05). Among children aged ≥ 24 months, there were no significant differences in either the presence of siblings or HFNC use in 2021 (Table 3).

Table 2

Epidemiological changes in characteristics of infants aged < 6 months
	2018–2020 (n = 216)	2021 (n = 117)	P-value
Sex: male, n (%)	117 (54.2)	59 (50.4)	0.566
Palivizumab indication, n (%) no unknown	9 (4.2) 183 (84.7) 24 (11.1)	1 (0.9) 112 (95.7) 4 (3.4)	0.0977
Palivizumab prophylaxis, n (%) no unknown	7 (3.2) 185 (85.6) 24 (11.1)	0 (0) 113 (96.6) 4 (3.4)	0.0491
Presence of siblings, n (%) no unknown	160 (74.1) 20 (9.3) 36 (16.7)	110 (94.0) 2 (1.7) 5 (4.3)	0.00256
Hospitalization duration mean days (SD)	6.05 (2.38)	6.37 (2.98)	0.284
Oxygen use rate, n (%)	100 (46.3)	63 (53.8)	0.207
HFNC use rate, n (%)	36 (16.7)	31 (26.5)	0.0444
Ventilator use rate, n (%)	3 (1.4)	2 (1.7)	1
Mortality rate, n (%)	0 (0)	0 (0)	NA
HFNC, high-flow nasal cannula; SD, standard deviation

Table 3

Epidemiological changes in characteristics of children aged ≥ 24 months
	2018–2020 (n = 85)	2021 (n = 65)	P-value
Sex: male, n (%)	40 (47.1)	39 (60.0)	0.138
Palivizumab indication, n (%) no unknown	1 (1.2) 58 (68.2) 26 (30.6)	4 (6.2) 45 (69.2) 16 (24.6)	0.174
Palivizumab prophylaxis, n (%) no unknown	1 (1.2) 58 (68.2) 26 (30.6)	1 (1.5) 45 (69.2) 19 (29.2)	1
Presence of siblings, n (%) no unknown	39 (45.9) 18 (21.2) 28 (32.9)	29 (44.6) 15 (23.1) 21 (32.3)	0.833
Hospitalization duration mean days (SD)	5.04 (1.71)	4.80 (1.88)	0.425
Oxygen use rate, n (%)	24 (28.2)	25 (38.5)	0.22
HFNC use rate, n (%)	3 (3.5)	3 (4.6)	1
Ventilator use rate, n (%)	0 (0)	0 (0)	NA
Mortality rate, n (%)	0 (0)	0 (0)	NA
HFNC, high-flow nasal cannula; SD, standard deviation

The present study highlights that a rapid and large increase in the number of hospitalizations within a short period resulted in a shortage of hospital beds. As a temporary measure, we managed to increase the number of pediatric beds from 20 to 30 at the Tokushima Prefectural Central Hospital. However, we could not admit children who needed hospitalization, even if they were only a few months old. We had to follow them up carefully and frequently as outpatients every day.

In addition, there was an increase in hospitalizations of children aged < 6 months. Most RSV-related deaths worldwide occur in children aged 0–6 months [4]. Due to the hospital bed shortage, vulnerable infants aged < 6 months were given priority hospitalization. Additional HFNC therapies were selected for them because HFNC is useful in mild to moderate cases of bronchiolitis that do not improve with oxygen therapy [13]. However, such therapies could not be provided to all children who required it, as both hospitals faced a shortage of HFNCs. This emphasizes the need to prepare a sufficient reserve supply of HFNCs for pandemic events.

We also found an increase in hospitalizations of children older than 24 months in 2021, the details of which are shown in Table 3. The data reflect the increase in the number of children who were susceptible to RSV infection. The need for oxygen use in these children increased by only 10%. This means that the RSV severity in children aged ≥ 24 months was not so high. The percentage of children aged ≥ 24 months who had siblings at home did not differ between 2018–2020 and 2021, whereas the corresponding percentage in infants aged < 6 months was higher in 2021. This might explain one of the reasons for younger infants to get infected at home by older siblings during the COVID-19 pandemic.

In Finland, the re-emergence of RSV infections has been associated with the lifting of COVID-19-related restrictions [7]. The number of COVID-19 cases in Japan was 230,304 (3,414 deaths) on December 31, 2020, increasing to 1,733,325 (18,393 deaths) in 2021 [14–16]. In Tokushima Prefecture, there were 199 cases of COVID-19 in 2020, increasing to a cumulative number of 3,291 cases by the end of 2021 [17], suggesting the outbreak continued beyond 2021. In fact, the Japanese government continues to recommend public health infection control measures, including avoiding crowded places [18]. In Finland, there has also been a resurgence of influenza; however, an influenza outbreak has not been observed in Japan yet [19], suggesting that the epidemiology of infectious diseases after the onset of COVID-19 is different in both countries. Although public health measures in Japan remained relatively strict, young children were generally exempt from wearing masks, making them susceptible to RSV infection, which may be acquired at daycare centers and elsewhere. Although age-based infection patterns changed in Japan in 2021, they did not change in Israel [6]. While Japan and Australia observed peak RSV infection outbreaks [8, 20], France did not [5]. Overall, these differences in RSV infection patterns may have been affected by differences in public health measures introduced to control COVID-19 spread, as well as local lifestyles.

The earlier-than-usual outbreak of RSV infections may be because palivizumab was not administered in time. Palivizumab helps to prevent severe disease and complications associated with RSV infection in high-risk children, and hence, its administration to eligible children is strongly recommended [21]. In the present study, there was no decrease in the prophylaxis rate, and the rate of hospitalizations among children indicated for palivizumab was unaffected. The Tokushima Pediatric Association alerted local medical institutions regarding the transmission of RSV and provided information based on the National Epidemiological Surveillance of Infectious Diseases in Japan. This may have suppressed RSV infection in high-risk children by facilitating the earlier initiation of palivizumab programs and timely inoculation.

This study had several limitations. Decisions regarding hospitalizations were at the physicians’ discretion and depended on inpatient bed availability and family circumstances. In addition, selection of therapies such as HFNC was not only decided at conferences by several doctors, but also by the doctor-in-charge. While this study only presented epidemiological data on RSV infections for a specific region of Japan, the findings may help develop preparedness strategies for future outbreaks.

The number of RSV infection-related hospitalizations increased in children aged < 6 months and in those older than 24 months at two pediatric emergency referral hospitals in Tokushima Prefecture between 2018–2020 and 2021. In 2021, the RSV infection rate peaks were observed 1–2 months earlier than those in the previous years. Hospitalizations were concentrated within a short period of time. Although the current pandemic is not yet over, we need to be aware that such pandemics can cause outbreaks of RSV infection that can increase the number of hospitalizations of pediatric patients requiring pulmonary support. The preparedness of medical systems, particularly in terms of the number of inpatient beds and the immediate availability of HFNCs, needs to be improved in order to handle such emergency situations.

COVID-19, coronavirus disease; HFNC, high-flow nasal cannula; RSV, respiratory syncytial virus.

Funding: The authors declare that no funds, grants, or other support were received during the preparation of this manuscript.

Clinical Trial Registration: Not applicable.

Acknowledgements: We would like to thank Editage (www.editage.com) for English language editing.

Competing interests: The authors have no relevant financial or non-financial interests to disclose.

Authors’ contributions:

Conceptualization:Koichi Shichijo, Shuji Kondo.

Methodology:Koichi Shichijo, Akiyoshi Takahashi, Tsutomu Watanabe, Shuji Kondo.

Formal analysis and investigation: Koichi Shichijo, Shoko Fukura, Shunsuke Takeuchi, Takahiro Tayama, Akemi Ono, Yuko Ichihara, Kenichi Suga, Hiroki Sato, Atsumi Takechi, Sonomi Matsumoto, Shuji Fujino, Takako Taniguchi, Akiyoshi Takahashi, Tsutomu Watanabe, Shuji Kondo

Writing - original draft preparation: Koichi Shichijo

Writing - review and editing: Kenichi Suga, Akiyoshi Takahashi, Tsutomu Watanabe, Shuji Kondo

Resources: Shoko Fukura, Shunsuke Takeuchi, Takahiro Tayama, Akemi Ono, Yuko Ichihara, Hiroki Sato, Atsumi Takechi, Sonomi Matsumoto, Shuji Fujino, Takako Taniguchi

Supervision: Tsutomu Watanabe, Shuji Kondo

All authors read and approved the final manuscript.

Ethics approval: This study was performed in line with the principles of the 1964 Declaration of Helsinki and its later amendments. Approval was granted by the Tokushima Prefectural Central Hospital Ethics Committee (approval number 21-37) and Tokushima Red Cross Hospital Ethics Committee (approval number 399).

Consent to participate: The requirement for informed consent was waived because the study was a retrospective study.

Consent to publish: Not applicable

Information on health and medical consultation. Avoid the Three Cs. Ministry of Health, Labour and Welfare. https://www.mhlw.go.jp/stf/covid-19/kenkou-iryousoudan_00006.html. Accessed 21 December 2022.
Shichijo K, Takeuchi S, Tayama T et al (2021) Patient attendance at a pediatric emergency referral hospital in an area with low COVID-19 incidence. PLoS ONE 16:e0258478. https://doi.org/10.1371/journal.pone.0258478
James E, Crowe Jr. (2011) Respiratory syncytial virus. In: Robert MK (ed) Nelson textbook of pediatrics, 19th edn. W.B. Saunders Co, Philadelphia, pp 1126-1129
Li Y, Wang X, Blau DM et al (2022) 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 399:2047-2064. https://doi.org//10.1016/S0140-6736(22)00478-0
Delestrain C, Danis K, Hau I, Behillil S, Billard M, Krajten L, Cohen R, Bont L, Epaud R (2021) Impact of COVID-19 social distancing on viral infection in France: A delayed outbreak of RSV. Pediatr Pulmonol 56:3669-3673. https://doi.org/10.1002/ppul.25644
Weinberger Opek M, Yeshayahu Y, Glatman-Freedman A, Kaufman Z, Sorek N, Brosh-Nissimov T (2021) Delayed respiratory syncytial virus epidemic in children after relaxation of COVID-19 physical distancing measures, Ashdod, Israel. Euro Surveill 26:2100706. https://doi.org/10.2807/1560-7917.ES.2021.26.29.2100706.
Kuitunen I, Artama M, Haapanen M, Renko M (2022) Respiratory virus circulation in children after relaxation of COVID-19 restrictions in fall 2021-A nationwide register study in Finland. J Med Virol 94:4528-4532. https://doi.org/10.1002/jmv.27857
Foley DA, Phuong LK, Peplinski J et al (2022) Examining the interseasonal resurgence of respiratory syncytial virus in Western Australia. Arch Dis Child 107:e1-e7. https://doi.org/10.1136/archdischild-2021-322507
RS virus infections 2018-2021 [Japanese]. National Institute of Infectious Diseases. https://www.niid.go.jp/niid/ja/rs-virus-m/rs-virus-iasrtpc/11081-506t.html. Accessed 21 December 2022
Trends in the number of reported fixed-point disease - Tokushima Prefecture Infectious Disease Information [Japanese]. Tokushima Prefectural Government. https://www.pref.tokushima.lg.jp/ippannokata/kenko/kansensho/2009090201227. Accessed 21 December 2022
Age distribution of patients with RS virus infection [Japanese]. National Institute of Infectious Diseases. https://www.niid.go.jp/niid/images/iasr/2022/4/506tf03.gif. Accessed 21 December 2022
Kanda Y (2013) Investigation of the freely-available easy-to-use software “EZR” (Easy R) for medical statistics. Bone Marrow Transplant 48:452-458. https://doi.org/10.1038/bmt.2012.244
Fainardi V, Abelli L, Muscarà M, Pisi G, Principi N, Esposito S (2021) Update on the role of high-flow nasal cannula in infants with bronchiolitis. Children (Basel)8:66. https://doi.org/10.3390/children8020066
Visualizing the data: information on COVID-19 infections. Ministry of Health, Labour and Welfare. https://covid19.mhlw.go.jp/en/. Accessed 21 December 2022
Current status of novel coronavirus infection and the response of the Ministry of Health (December 31, 2020 version) [Japanese]. Ministry of Health, Labour and Welfare. https://www.mhlw.go.jp/stf/newpage_15828.html. Accessed 21 December 2022
Current status of novel coronavirus infection and the response of the Ministry of Health (December 31, 2021 version) [Japanese]. Ministry of Health, Labour and Welfare. https://www.mhlw.go.jp/stf/newpage_23137.html. Accessed 21 December 2022
Occurrence in the prefecture [Japanese]. Tokushima Prefectural Government. https://www.pref.tokushima.lg.jp/jigyoshanokata/kenko/kansensho/5036761/. Accessed 21 December 2022
The 65th Advisory Board on Countermeasures to Combat Novel Coronavirus Infections [Japanese]. Ministry of Health, Labour and Welfare. https://www.mhlw.go.jp/stf/seisakunitsuite/bunya/0000121431_00294.html. Accessed 21 December 2022
Graph comparing influenza over the past 10 years [Japanese]. National Institute of Infectious Diseases. https://www.niid.go.jp/niid/ja/flu-m/813-idsc/map/130-flu-10year.html. Accessed 21 December 2022
Ujiie M, Tsuzuki S, Nakamoto T, Iwamoto N (2021) Resurgence of respiratory syncytial virus infections during COVID-19 pandemic, Tokyo, Japan. Emerg Infect Dis 27:2969-2970. https://doi.org/10.3201/eid2711.211565
Andabaka T, Nickerson JW, Rojas-Reyes MX, Rueda JD, Bacic Vrca V, Barsic B (2013) Monoclonal antibody for reducing the risk of respiratory syncytial virus infection in children. Cochrane Database Syst Rev 30:CD006602. https://doi.org/10.1002/14651858.CD006602.pub4

No competing interests reported.

Download PDF

Version 1

posted

You are reading this latest preprint version

A surge in respiratory syncytial virus infection-related hospitalizations associated with the COVID-19 pandemic: An observational study at pediatric emergency referral hospitals in Tokushima Prefecture

Status:

Version 1

Abstract

Purpose

Methods

Results

Conclusions

Figures

What Is Known

Introduction

Materials And Methods

Study design and patients

Data source and collection

Data analysis

Results

Discussion

Abbreviations

Declarations

References

Additional Declarations

Status:

Version 1