{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T18:31:10Z","timestamp":1778005870828,"version":"3.51.4"},"update-to":[{"DOI":"10.1371\/journal.pcbi.1008679","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2021,2,10]],"date-time":"2021-02-10T00:00:00Z","timestamp":1612915200000}}],"reference-count":31,"publisher":"Public Library of Science (PLoS)","issue":"1","license":[{"start":{"date-parts":[[2021,1,29]],"date-time":"2021-01-29T00:00:00Z","timestamp":1611878400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001863","name":"New Energy and Industrial Technology Development Organization","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100001863","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.ploscompbiol.org"],"crossmark-restriction":false},"short-container-title":["PLoS Comput Biol"],"abstract":"<jats:p>After slowing down the spread of the novel coronavirus COVID-19, many countries have started to relax their confinement measures in the face of critical damage to socioeconomic structures. At this stage, it is desirable to monitor the degree to which political measures or social affairs have exerted influence on the spread of disease. Though it is difficult to trace back individual transmission of infections whose incubation periods are long and highly variable, estimating the average spreading rate is possible if a proper mathematical model can be devised to analyze daily event-occurrences. To render an accurate assessment, we have devised a state-space method for fitting a discrete-time variant of the Hawkes process to a given dataset of daily confirmed cases. The proposed method detects changes occurring in each country and assesses the impact of social events in terms of the temporally varying reproduction number, which corresponds to the average number of cases directly caused by a single infected case. Moreover, the proposed method can be used to predict the possible consequences of alternative political measures. This information can serve as a reference for behavioral guidelines that should be adopted according to the varying risk of infection.<\/jats:p>","DOI":"10.1371\/journal.pcbi.1008679","type":"journal-article","created":{"date-parts":[[2021,1,29]],"date-time":"2021-01-29T13:42:47Z","timestamp":1611927767000},"page":"e1008679","update-policy":"https:\/\/doi.org\/10.1371\/journal.pcbi.corrections_policy","source":"Crossref","is-referenced-by-count":34,"title":["Estimating the time-varying reproduction number of COVID-19 with a state-space method"],"prefix":"10.1371","volume":"17","author":[{"given":"Shinsuke","family":"Koyama","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Taiki","family":"Horie","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5745-7736","authenticated-orcid":true,"given":"Shigeru","family":"Shinomoto","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2021,1,29]]},"reference":[{"key":"pcbi.1008679.ref001","doi-asserted-by":"crossref","DOI":"10.1002\/9781118638033","volume-title":"An Essential Guide","author":"GN Milligan","year":"2015"},{"issue":"5934","key":"pcbi.1008679.ref002","doi-asserted-by":"crossref","first-page":"1557","DOI":"10.1126\/science.1176062","article-title":"Pandemic potential of a strain of influenza A (H1N1): early findings","volume":"324","author":"C Fraser","year":"2009","journal-title":"science"},{"issue":"4","key":"pcbi.1008679.ref003","doi-asserted-by":"crossref","first-page":"599","DOI":"10.1137\/S0036144500371907","article-title":"The mathematics of infectious diseases","volume":"42","author":"HW Hethcote","year":"2000","journal-title":"SIAM review"},{"issue":"2","key":"pcbi.1008679.ref004","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1016\/j.idm.2017.02.001","article-title":"Mathematical epidemiology: Past, present, and future","volume":"2","author":"F Brauer","year":"2017","journal-title":"Infectious Disease Modelling"},{"issue":"1","key":"pcbi.1008679.ref005","doi-asserted-by":"crossref","first-page":"195","DOI":"10.30707\/LiB5.1Blackwood","article-title":"An introduction to compartmental modeling for the budding infectious disease modeler","volume":"5","author":"JC Blackwood","year":"2018","journal-title":"Letters in Biomathematics"},{"issue":"772","key":"pcbi.1008679.ref006","first-page":"700","article-title":"A contribution to the mathematical theory of epidemics","volume":"115","author":"WO Kermack","year":"1927","journal-title":"Proceedings of the royal society of london Series A, Containing papers of a mathematical and physical character"},{"issue":"10225","key":"pcbi.1008679.ref007","doi-asserted-by":"crossref","first-page":"689","DOI":"10.1016\/S0140-6736(20)30260-9","article-title":"Nowcasting and forecasting the potential domestic and international spread of the 2019-nCoV outbreak originating in Wuhan, China: a modelling study","volume":"395","author":"JT Wu","year":"2020","journal-title":"The Lancet"},{"key":"pcbi.1008679.ref008","doi-asserted-by":"crossref","unstructured":"Rizoiu MA, Mishra S, Kong Q, Carman M, Xie L. 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