A methodology to generate epidemic scenarios for emerging infectious diseases based on the use of key calendar events

This work presents a methodology to recreate the observed dynamics of emerging infectious diseases and to generate short-term forecasts for their evolution based on superspreading events occurring on key calendar dates. The method is illustrated by the COVID-19 pandemic dynamics in Mexico and Peru up to January 31, 2022. We also produce scenarios obtained through the estimation of a time-dependent contact rate, with the main assumption that the dynamic of the disease is determined by the mobility and social activity of the population during holidays and other important calendar dates. First, historical changes in the effective contact rate on predetermined dates are estimated. Then, this information is used to forecast scenarios under the assumption that the trends of the effective contact rate observed in the past will be similar on the same but future key calendar dates. All other conditions are assumed to remain constant in the time scale of the projections. One of the main features of the methodology is that it avoids the necessity of fixing values of the dynamic parameters for the whole prediction period. Results show that considering the key dates as reference information is useful to recreate the different outbreaks, slow or fast-growing, that an epidemic can present and, in most cases, make good short-term predictions. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement The author(s) received no specific funding for this work. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: N/A I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes All the data used in this work are available in the public domain: https://www.gob.mx/salud/documentos/datos-abiertos-152127 https://www.datosabiertos.gob.pe/group/datos-abiertos-de-covid-19?sort\_by=changed&f%5B0%5D=field\_tags%3A913&f%5B1%5D=field_tags%3A489 [https://www.datosabiertos.gob.pe/group/datos-abiertos-de-covid-19?sort\_by=changed&f%5B0%5D=field\_tags%3A913&f%5B1%5D=field_tags%3A489][1] [1]: https://www.datosabiertos.gob.pe/group/datos-abiertos-de-covid-19?sort_by=changed&f%5B0%5D=field_tags%3A913&f%5B1%5D=field_tags%3A489