Projecting hospital utilization during the COVID-19 outbreaks in the United States

Estimating required ‘lockdown’ cycles before immunity to SARS-CoV-2: model-based analyses of susceptible population sizes, ‘S0’, in seven European countries, including the UK and Ireland

Background: Following stringent social distancing measures, some European countries are beginning to report a slowed or negative rate of growth of daily case numbers testing positive for the novel coronavirus. The notion that the first wave of infection is close to its peak begs the question of whether future peaks or ‘second waves’ are likely. We sought to determine the current size of the effective (i.e. susceptible) population for seven European countries—to estimate immunity levels following this first wave. Methods: We used Bayesian model inversion to estimate epidemic parameters from the reported case and death rates from seven countries using data from late January 2020 to April 5th 2020. Two distinct generative model types were employed: first a continuous time dynamical-systems implementation of a Susceptible-Exposed-Infectious-Recovered (SEIR) model, and second a partially observable Markov Decision Process or hidden Markov model (HMM) implementation of an SEIR model. Both models parameterise the size of the initial susceptible population (‘S0’), as well as epidemic parameters. Results: Both models recapitulated the dynamics of transmissions and disease as given by case and death rates. Crucially, maximum a posteriori estimates of S0 for each country indicated effective population sizes of below 20% (of total population size), under both the continuous time and HMM models. Using a Bayesian weighted average across all seven countries and both models, we estimated that 6.4% of the total population would be immune. From the two models, the maximum percentage of the effective population was estimated at 19.6% of the total population for the UK, 16.7% for Ireland, 11.4% for Italy, 12.8% for Spain, 18.8% for France, 4.7% for Germany and 12.9% for Switzerland. Conclusion: Our results indicate that after the current wave, a large proportion of the total population will remain without immunity.

Projecting demand for critical care beds during COVID-19 outbreaks in Canada

BACKGROUND

Increasing numbers of coronavirus disease 2019 (COVID-19) cases in Canada may create substantial demand for hospital admission and critical care. We evaluated the extent to which self-isolation of mildly ill people delays the peak of outbreaks and reduces the need for this care in each Canadian province.

METHODS

We developed a computational model and simulated scenarios for COVID-19 outbreaks within each province. Using estimates of COVID-19 characteristics, we projected the hospital and intensive care unit (ICU) bed requirements without self-isolation, assuming an average number of 2.5 secondary cases, and compared scenarios in which different proportions of mildly ill people practised self-isolation 24 hours after symptom onset.

RESULTS

Without self-isolation, the peak of outbreaks would occur in the first half of June, and an average of 569 ICU bed days per 10 000 population would be needed. When 20% of cases practised self-isolation, the peak was delayed by 2-4 weeks, and ICU bed requirement was reduced by 23.5% compared with no self-isolation. Increasing self-isolation to 40% reduced ICU use by 53.6% and delayed the peak of infection by an additional 2-4 weeks. Assuming current ICU bed occupancy rates above 80% and self-isolation of 40%, demand would still exceed available (unoccupied) ICU bed capacity.

INTERPRETATION

At the peak of COVID-19 outbreaks, the need for ICU beds will exceed the total number of ICU beds even with self-isolation at 40%. Our results show the coming challenge for the health care system in Canada and the potential role of self-isolation in reducing demand for hospital-based and ICU care.

Condições de trabalho e falta de informações sobre o impacto da COVID-19 entre trabalhadores da saúde

Resumo Introdução: diante da pandemia da COVID-19, torna-se importante rever questões de proteção da saúde dos trabalhadores. Objetivo: discutir as condições de saúde e segurança dos trabalhadores que cuidam de pacientes com COVID-19, sob a perspectiva das informações levantadas por seus representantes de classe profissional e de recomendações institucionais. Métodos: levantamento de informações na literatura científica, em documentos e orientações de entidades oficiais de saúde, em fontes de entidades sindicais e de representação de classes de profissionais de saúde. Discussão: começamos pela descrição das características da infecção pelo SARS-CoV-2 no processo de trabalho em saúde; exemplificamos as iniciativas de organizações representativas dos trabalhadores para o enfrentamento da COVID-19; descrevemos o cenário do trabalho em saúde na pandemia no Brasil; apresentamos o relato das medidas de proteção e de enfrentamento da doença orientadas por entidades e organismos nacionais e internacionais. Finalizamos discutindo que a exposição desses trabalhadores pode levar a outros eventos em saúde, necessitando medidas de adequação em relação a número de profissionais, melhoria na organização e nas condições de trabalho, fornecimento de equipamentos de proteção individual em quantidade e qualidade adequadas e implantação de medidas que propiciem o fortalecimento das equipes para o enfrentamento da COVID-19.