Dataset Information

Impact of lockdown on COVID-19 epidemic in Ile-de-France and possible exit strategies.

ABSTRACT:

Background

More than half of the global population is under strict forms of social distancing. Estimating the expected impact of lockdown and exit strategies is critical to inform decision makers on the management of the COVID-19 health crisis.

Methods

We use a stochastic age-structured transmission model integrating data on age profile and social contacts in Île-de-France to (i) assess the epidemic in the region, (ii) evaluate the impact of lockdown, and (iii) propose possible exit strategies and estimate their effectiveness. The model is calibrated to hospital admission data before lockdown. Interventions are modeled by reconstructing the associated changes in the contact matrices and informed by mobility reductions during lockdown evaluated from mobile phone data. Different types and durations of social distancing are simulated, including progressive and targeted strategies, with large-scale testing.

Results

We estimate the reproductive number at 3.18 [3.09, 3.24] (95% confidence interval) prior to lockdown and at 0.68 [0.66, 0.69] during lockdown, thanks to an 81% reduction of the average number of contacts. Model predictions capture the disease dynamics during lockdown, showing the epidemic curve reaching ICU system capacity, largely strengthened during the emergency, and slowly decreasing. Results suggest that physical contacts outside households were largely avoided during lockdown. Lifting the lockdown with no exit strategy would lead to a second wave overwhelming the healthcare system, if conditions return to normal. Extensive case finding and isolation are required for social distancing strategies to gradually relax lockdown constraints.

Conclusions

As France experiences the first wave of COVID-19 pandemic in lockdown, intensive forms of social distancing are required in the upcoming months due to the currently low population immunity. Extensive case finding and isolation would allow the partial release of the socio-economic pressure caused by extreme measures, while avoiding healthcare demand exceeding capacity. Response planning needs to urgently prioritize the logistics and capacity for these interventions.

SUBMITTER: Di Domenico L

PROVIDER: S-EPMC7391016 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:BackgroundIn response to the ongoing COVID-19 pandemic, several countries adopted measures of social distancing to a different degree. For many countries, after successfully curbing the initial wave, lockdown measures were gradually lifted. In Belgium, such relief started on May 4th with phase 1, followed by several subsequent phases over the next few weeks.MethodsWe analysed the expected impact of relaxing stringent lockdown measures taken according to the phased Belgian exit strategy. We developed a stochastic, data-informed, meta-population model that accounts for mixing and mobility of the age-structured population of Belgium. The model is calibrated to daily hospitalization data and is able to reproduce the outbreak at the national level. We consider different scenarios for relieving the lockdown, quantified in terms of relative reductions in pre-pandemic social mixing and mobility. We validate our assumptions by making comparisons with social contact data collected during and after the lockdown.ResultsOur model is able to successfully describe the initial wave of COVID-19 in Belgium and identifies interactions during leisure/other activities as pivotal in the exit strategy. Indeed, we find a smaller impact of school re-openings as compared to restarting leisure activities and re-openings of work places. We also assess the impact of case isolation of new (suspected) infections, and find that it allows re-establishing relatively more social interactions while still ensuring epidemic control. Scenarios predicting a second wave of hospitalizations were not observed, suggesting that the per-contact probability of infection has changed with respect to the pre-lockdown period.ConclusionsContacts during leisure activities are found to be most influential, followed by professional contacts and school contacts, respectively, for an impending second wave of COVID-19. Regular re-assessment of social contacts in the population is therefore crucial to adjust to evolving behavioral changes that can affect epidemic diffusion.

Project description:Objectif Évaluation de l’impact du premier mois de confinement lors de l’épidémie Covid 19 sur l’activité de chirurgie carcinologique des services universitaires d’otorhinolaryngologie en Île-de-France. Matériel et méthodes Étude observationnelle, prospective, multicentrique menée au sein de 6 services universitaires (Paris Centre, Nord, Est et Sorbonne) d’otorhinolaryngologie sur le mois précédant (Groupe A) et suivant (Groupe B) le confinement instauré le 17/03/2020. Objectif principal : évaluer l’impact sur l’activité carcinologique chirurgicale. Objectifs secondaires : évaluer les caractéristiques de la population, les modalités pratiques des interventions, les suites opératoires, l’évolution Covid des patients et des otorhinolaryngologistes et les effets néfastes. Résultats Deux cent vingt-quatre interventions étaient réalisées. Une diminution de 10,9 % de l’activité était notée, sans différence significative entre les services. Les carcinomes épidermoïdes et la localisation au niveau du larynx, de l’hypopharynx, de l’oropharynx, de la cavité buccale, des fosses nasales et sinus de la face prédominaient, avec respectivement 79 % et 75,8 % des interventions, sans différence significative entre les groupes. Les tumeurs classées T3/4 et N2/3 étaient plus fréquentes au sein du Groupe B (p = 0,002 et 0,0004). Il n’existait pas de différence significative entre les groupes en termes d’abord chirurgical, de modalités de reconstruction, de suites opératoires et de durée de séjour en soins intensifs ou en réanimation, de trachéotomie, de sonde nasogastrique et d’hospitalisation. Aucun patient n’était testé positif pour la Covid 19 au sein du Groupe A pour trois au sein du Groupe B, sans effets néfastes. Les otorhinolaryngologistes qui participaient aux interventions ne développaient pas de symptômes évocateurs d’une infestation par la Covid 19. Conclusion Cette étude souligne que l’épidémie Covid 19 et le confinement n’ont que légèrement altéré la chaîne diagnostique et thérapeutique chirurgicale des cancers pris en charge dans les services universitaires ORL d’Île-de-France, conservant toutes les chances de survie, sans favoriser la diffusion du virus.