Kyungmin Huh1, Jaehun Jung2, Jinwook Hong2, MinYoung Kim3,4, Jong Gyun Ahn3, Jong-Hun Kim5, Ji-Man Kang3,4. 1. Division of Infectious Diseases, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. 2. Artificial Intelligence and Big-Data Convergence Center, Gil Medical Center, Gachon University College of Medicine, Incheon, Korea. 3. Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea. 4. Institute for Immunology and Immunological Diseases, Yonsei University College of Medicine, Seoul, Korea. 5. Department of Social and Preventive Medicine, Sungkyunkwan University School of Medicine, Suwon, Gyeonggi-do, Korea.
Abstract
BACKGROUND: Many countries have implemented nonpharmaceutical interventions (NPIs) to slow the spread of coronavirus disease 2019 (COVID-19). We aimed to determine whether NPIs led to the decline in the incidences of respiratory infections. METHODS: We conducted a retrospective, ecological study using a nationwide notifiable diseases database and a respiratory virus sample surveillance collected from January 2016 through July 2020 in the Republic of Korea. Intervention period was defined as February-July 2020, when the government implemented NPIs nationwide. Observed incidences in the intervention period were compared with the predicted incidences by an autoregressive integrated moving average model and the 4-year mean cumulative incidences (CuIs) in the same months of the preintervention period. RESULTS: Five infectious diseases met the inclusion criteria: chickenpox, mumps, invasive pneumococcal disease, scarlet fever, and pertussis. The incidences of chickenpox and mumps during the intervention period were significantly lower than the prediction model. The CuIs (95% confidence interval) of chickenpox and mumps were 36.4% (23.9-76.3%) and 63.4% (48.0-93.3%) of the predicted values. Subgroup analysis showed that the decrease in the incidence was universal for chickenpox, while mumps showed a marginal reduction among those aged <18 years, but not in adults. The incidence of respiratory viruses was significantly lower than both the predicted incidence (19.5%; 95% confidence interval, 11.8-55.4%) and the 4-year mean CuIs in the preintervention period (24.5%; P < .001). CONCLUSIONS: The implementation of NPIs was associated with a significant reduction in the incidences of several respiratory infections in Korea.
BACKGROUND: Many countries have implemented nonpharmaceutical interventions (NPIs) to slow the spread of coronavirus disease 2019 (COVID-19). We aimed to determine whether NPIs led to the decline in the incidences of respiratory infections. METHODS: We conducted a retrospective, ecological study using a nationwide notifiable diseases database and a respiratory virus sample surveillance collected from January 2016 through July 2020 in the Republic of Korea. Intervention period was defined as February-July 2020, when the government implemented NPIs nationwide. Observed incidences in the intervention period were compared with the predicted incidences by an autoregressive integrated moving average model and the 4-year mean cumulative incidences (CuIs) in the same months of the preintervention period. RESULTS: Five infectious diseases met the inclusion criteria: chickenpox, mumps, invasive pneumococcal disease, scarlet fever, and pertussis. The incidences of chickenpox and mumps during the intervention period were significantly lower than the prediction model. The CuIs (95% confidence interval) of chickenpox and mumps were 36.4% (23.9-76.3%) and 63.4% (48.0-93.3%) of the predicted values. Subgroup analysis showed that the decrease in the incidence was universal for chickenpox, while mumps showed a marginal reduction among those aged <18 years, but not in adults. The incidence of respiratory viruses was significantly lower than both the predicted incidence (19.5%; 95% confidence interval, 11.8-55.4%) and the 4-year mean CuIs in the preintervention period (24.5%; P < .001). CONCLUSIONS: The implementation of NPIs was associated with a significant reduction in the incidences of several respiratory infections in Korea.