Decreased human respiratory syncytial virus activity during COVID-19 pandemic in associated with non-pharmaceutical measurement compared to pre- pandemic period Keita WAGATSUMA1 ([email protected]), and Reiko SAITO1,2 1 Division of International Health (Public Health), Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Niigata City, Japan 2 Infectious Diseases Research Center of Niigata University in Myanmar (IDRC), Yangon, Yangon Region, Myanmar RESULTS ` BACKGROUNDS METHODS RESULTS 1.2. Travelers data Figure 1: Weekly HRSV activity based on national HRSV surveillance data, week 1, 2014 to Figure 3: Correlation between the monthly number of HRSV cases per sentinel site (HRSV  Human respiratory syncytial virus (HRSV) activity week 53, 2020. activity) and retails of hand hygiene, the number of international and domestic air The monthly number of international and domestic 4 passengers, and meteorological conditions between the corresponding periods in 2020. 2014 was at very low level in 2020 in Japan. Correlation between monthly HRSV activity and retails of hand hygiene from Jan to Nov 2020 passengers (per 1,000 peoples) were extracted from the 2015 Average 85% 1.6 r = −0.69 3 1.4  Non-pharmaceutical interventions (NPIs) such as statistics of air transport, Ministry of Land, Infrastructure, 2016 1.2 P=0.01 reduction 1 0.8 R2=0.47 v.s. 2017 0.6 0.4 N=11 Transport and Tourism in Japan from Jan to Oct 2020. 0.2 sanitary measures and travel restrictions aimed 2018 0 2 0 2 4 6 8 10 12 14 against controls of coronavirus disease 2019 1.3. Hygiene products 2019 Retails of hand hygiene (billion) 2020 Correlation between monthly HRSV activity and number of domestic airline passengers from Jan to Oct 2020

The monthly retails of hand hygiene (hand soap and ethyl 1.6 r = 0.91 1.4 (COVID-19) may affect the transmission of HRSV. 1 1.2 P<0.001 v.s. 1 2 alcohol) (billion) were extracted from the Statistics of 0.8 R =0.83 0.6 0.4 N=10

No. HRSV cases per sentinel site sentinel cases per HRSV No. 0.2 Production of Chemical Industry of the Ministry of 0 -0.2 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 OBJECTIVES Economy and Industry in Japan from Jan to Nov 2020. 0 No. domestic airline passengers (/ 1000 peoples) 1 8 15 22 29 36 43 50 Correlation between monthly HRSV activity and number of international airline passengers from Jan to Oct 2020 r = 0.94 Epidemiologic week 1.8 1.4. Meteorological data 1.6  To compare HRSV activity in 2020 compared to 1.4 P<0.0001 v.s. 1.2 2 1 R =0.88  The average number of HRSV cases per sentinel site for 0.8 The monthly mean temperature (℃) and relative humidity 0.6 N=10 0.4 the past 6 years from 2014 to . 0.2 epidemiologic weeks 1–53 in 2020 decreased by almost 85% 0 (%) were extracted from the Japan Meteorological Agency 0 500 1000 1500 2000 2500 No. international airline passengers (/ 1000 peoples)  To evaluate association between the HRSV (P<0.001) compared to those in preceding 6 epidemiologic site sentinel per cases HRSV No. (JMA) from Jan to Dec 2020. years from 2014 to 2019. Correlation between monthly HRSV activity and average temperature from Jan to Dec 2020 1.6 r = −0.74 1.4 activity in 2020 and indicators for NPIs such as 1.2 P=0.005 v.s. 1 Figure 2: Monthly number of HRSV cases per sentinel site, retails of hand hygiene, number 0.8 R2=0.55 0.6 0.4 N=12 of international and domestic air passengers, and meteorological conditions in 2020. 0.2 retails of hand hygiene, number of international 2. Statistical analysis: 0 -0.2 0 5 10 15 20 25 30 35 HRSV Retails of hand hygiene Average temperature (℃) 2.1. Comparison analysis of the weekly HRSV activity 1.6 14 and domestic airline passengers and Correlation between monthly HRSV activity and relative humidity from Jan to Dec 2020 1.4 12 The weekly number of HRSV cases per sentinel sites for 2 r = −0.68 meteorological conditions. 1.2 1.5 P=0.01 v.s. 10 2 weeks 1-53 in 2020 was compared with the mean of the 1 R =0.47 1 N=12 8 0.5 corresponding period in the previous 6 years (2014-2019) 0.8 billion) 0 0 10 20 30 40 50 60 70 80 90 100 6 -0.5 METHODS ( Yen Relative humidity (%) using a weekly paired difference t-test. 0.6 4 0.4 1. Data: 0.2 2 No. HRSV cases per sentinel site sentinel per cases HRSV No. SUMMARY 2.2. Correlation analysis between monthly HRSV activity 0 0 1.1. National HRSV surveillance data and indicator of NPIs and meteorological conditions No. domestic airline passengers Relative humidity  This study suggested possible association between The weekly number of HRSV cases per sentinel site was For the correlation analysis, the weekly number of HRSV No. international airline passengers Average temperature 40 100 extracted from the Infectious Disease Weekly Report cases per sentinel sites was calculated on a monthly basis. 10000 decreased HRSV activity and sanitary measures / travel

8000 ) (IDWR), sourced from the National Epidemiological Pearson’s correlation coefficients between the monthly 30 75 % restrictions for COVID-19 in Japan, suggesting the Surveillance of Infectious Diseases (NESID) published by number of HRSV cases per sentinel site and retails of hand 6000 NPIs can contribute to suppress HRSV activity. 20 50 National Institute of Infectious Diseases (NIID) under the hygiene, number of international and domestic airline 4000

Ministry of Health, Welfare and Labour in Japan passengers and meteorological conditions between the 10 25 ( humidity Relative

2000 Average temperature (℃) temperature Average (MHLW) for epidemiologic weeks 1-53, in 2014-2020. corresponding periods in 2020 (see Figure 3). passengers No. peoples) (/1000 ACKNOWLEDGEMENTS 0 0 0 This study was funded by the J-GRID from AMED [grant number 15fm0108009h0001-19fm0108009h0005]; and by Grants-in-Aid for Scientific Research (KAKENHI) [grant number 18K10043] from MEXT, Japan. COI: All authors have no COI relationship to disclose. 2020 2020