Long COVID-19 is likely to increase healthcare demands across the health system, including emergency departments, hospital admissions, primary care visits, specialists appointments, and home care and rehabilitation services.
The clinical care burden of long COVID-19 is the greatest in the first 3 months after testing and is likely to place the greatest demand on primary care services.
Patients with severe COVID-19 illness are more likely to place longer-term demands (4-6 months) on specialist care due to respiratory, circulatory, endocrine, metabolic, psychiatric and unspecified conditions.
McLean, M; Williams-Roberts, H; Reeder, B; Howell-Spooner, B; Ellsworth, C. What are long COVID's demands on the healthcare system, and its severity of the illness? 2021 Jul 12, Document no.: EPM210602 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2021. 23 p. (CEST rapid review report).
The frequency of Long COVID symptoms varies widely across studies based on populations studied, duration of follow up and methods of assessment of symptoms.
It is estimated that 1 in 50 persons experience Long COVID symptoms after 12 weeks; however, higher estimates up to 80% have been reported in studies with a greater proportion of persons who were previously hospitalized. A recent study of a mixed cohort of 96 persons found that only 22.9% had no symptoms at 12 months post diagnosis.
A wide range of symptoms affecting multiple organ systems has been reported. For many persons symptoms improve over time while others experience persistent and/or new symptoms. Among studies with the longest duration of follow up, the most frequently reported symptoms included fatigue (up to 65%), dyspnea (up to 50%), headache (up to 45%), anosmia/ageusia (up to 25%), cognitive memory/concentration (up to 39.6%) and sleep disorders (up to 26%).
Few studies estimated the duration of symptoms with estimates ranging from 2.2% for 6 months and 27% for 7-9 months.
The mechanism(s) leading to Long COVID remain unclear but those experiencing post acute sequelae tend to be older, have a greater number of symptoms during the acute phase of illness or manifest specific symptoms and live with multiple comorbid conditions such as obesity.
The lack of consensus on a definition of Long COVID contributes to marked variations in robust prevalence estimates.
Williams-Roberts, H; Groot, G; Reeder, B; Howell-Spooner, B; Ellsworth, C. What is the incidence and duration of Long COVID cases? 2021 Jul 09, Document no.: EPM210601 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2021. 19 p. (CEST rapid review report).
· There is marked heterogeneity across studies in reported estimates of the proportion of asymptomatic SARS CoV-2 infections that range from 1% to 80%.
· The proportion of SARS CoV-2 infections that are asymptomatic is related to the method of estimation, the population studied, setting and the timing of the estimation during the epidemic.
Williams-Roberts, H; Basran, J; Dalidowicz, M; Young, C; Mueller, M. What proportion of disease transmission is due to persons who are asymptomatic over the entire course of illness? 2020 Jun 2; Document no.: EPM051301 RR. In: COVID-19 Rapid Evidence Reviews [Internet]. SK: SK COVID Evidence Support Team, c2020. 33 p. (CEST rapid review report)