Alternatives to conventional hospitalisation that enhance health systems' capacity to treat COVID-19.

COVID-19 has led to hospitals exceeding their usual capacity and, in some cases, being forced to fully commit to COVID-19 management. Overwhelmed hospitals have established more demanding admission criteria, which have severely impacted long-term care facilities such as nursing homes. Other vulnerable groups, including homeless people, economically disadvantaged communities, and Black residents of US inner cities, have also been affected by high COVID-19 incidence rates and concomitant shortcomings in medical assistance. In this context, the need for alternative care models for COVID-19 management outside the hospital has emerged.

On Nov 25, 2020, the Centers for Medicare & Medicaid Services announced a comprehensive strategy to enhance hospital capacity amid the surge of COVID-19 cases that expands the Hospital Without Walls programme and builds on previous work by the same services to expand telehealth coverage. The new strategy encompasses hospital-at-home units, the temporary certification of ambulatory surgical centres as hospitals, and the provision of inpatient care for longer than is normally allowed. Thus far, various outpatient alternatives have been proposed, adapted to local needs and resources. From providing shelter to patients whose housing does not permit quarantining to treating patients with non-severe COVID-19, the aims of the outpatient alternatives are translated into different levels of care intensity.

Infection between cohabitants, especially those living in economically deprived environments and overcrowded housing, is one of the main drivers of COVID-19 dissemination. Individual, well ventilated rooms and separate bathrooms are needed at home to appropriately quarantine people infected with SARS-CoV-2 and ensure the safety of cohabitants. These requirements are unattainable for many people, even in high-income countries. Shelter hospitals are civil buildings, such as sports pavilions or hotels, that are adapted to accommodate patients with COVID-19 not needing acute medical care. Patients can be referred from the community (including primary care) or hospitals (if they are discharged early with asymptomatic or mild disease). When hospital capacity is particularly under stress, alternatives are needed to provide essentially the same care as in hospital wards. Patients with non-severe COVID-19 can be treated in civil buildings or receive acute hospital care at home. Patients with moderate COVID-19 might rapidly worsen; therefore, other than optimising admission criteria, these alternatives should be able to provide adequate intermediate care and prioritised transfer to hospital within hours. This model has been applied by adapting sports pavilions, concert venues, and hotels, in addition to hospital-at-home units. Hospital-at-home units might be repurposed to manage patients with non-severe COVID-19 at their homes or nursing homes. In-person visits by nursing and medical staff can be combined with telemedicine to increase capacity while preserving the quality of care.

Fangcang shelter hospitals in China played a major role in tackling the first wave of the pandemic. These hospitals were rapidly deployed by use of pre-existing civil buildings and thousands of patients with COVID-19, including many with moderate COVID-19, were managed with good outcomes. Medicalised hotels can provide complex care to patients with COVID-19, including those with severe baseline conditions or solid organ transplant recipients.

By improving the early detection of complications, the number of patients with mild COVID-19 but with risk factors for clinical worsening who are treated outside of hospital can be increased. Although this approach might rely on in-person visits, this model has also been facilitated by the application of telemedicine and monitoring devices. For example, so-called virtual hospitals have been established for patients discharged from emergency departments8, 9 and for health-care workers with COVID-19.

Although there are some proof-of-concept data of the utility of alternatives for outpatient management of patients with COVID-19, many gaps remain. Adequate strategies for the clinical assessment of patients according to disease severity should be better characterised. Developing standardised criteria for allocating patients to the best fitting strategy should be a priority, although there is probably room for hybrid approaches. In addition, international guidance is required for the adaptation of civil buildings, especially with respect to staff safety and logistical needs. The deployment of alternative outpatient models in a specific setting should be planned and evaluated; therefore, further information on the cost-effectiveness of these models is warranted, as it might affect decisions such as timing (eg, opening only during surges or until the pandemic is over), staffing (ad hoc or structural), or whether some models could be used for other purposes (eg, vaccination delivery).

In conclusion, outpatient alternatives to conventional hospitalisation are promising models to improve the resilience of health systems against COVID-19.