Epidemiological characteristics of COVID-19: a systematic review and meta-analysis

Abstract

<jats:title>Abstract</jats:title> <jats:p>Our understanding of the Coronavirus disease 2019 (COVID-19) continues to evolve and there are many unknowns about its epidemiology. This study aims to synthesise case fatality rate (CFR) among confirmed COVID-19 patients, incubation period and time from onset of COVID-19 symptoms to first medical visit, intensive care unit (ICU) admission, recovery, and death. We searched MEDLINE, Embase, Google Scholar, and bibliographies of relevant articles from 01 December 2019 to 11 March 2020 without any language restrictions. Quantitative studies that recruited people with confirmed COVID-19 diagnosis were included. Two independent reviewers extracted the data. Out of 1675 non-duplicate studies, 43 were included in the meta-analysis. The pooled mean incubation period was 5.68 (99% confidence interval [CI]: 4.78, 6.59) days. The pooled mean number of days from the onset of COVID-19 symptoms to first clinical visit was 4.92 (95% CI: 3.95, 5.90), ICU admission was 9.84 (95% CI: 8.78, 10.90), recovery was 18.55 (95% CI: 13.69, 23.41), and death was 15.93 (95% CI: 13.07, 18.79). Pooled CFR among confirmed COVID-19 patients was 0.02 (95% CI: 0.02, 0.03). We found that the incubation period and lag between the onset of symptoms and first clinical visit for COVID-19 are longer than other respiratory viral infections including Middle East respiratory syndrome and severe acute respiratory syndrome; however, the current policy of 14 days of mandatory quarantine for everyone potentially exposed to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) might be too conservative. Longer quarantine periods might be more justified for extreme cases.</jats:p>

COVID-19 among patients with hepatitis B or hepatitis C: A systematic review

“…We summarized data from 235 patients with SARS-CoV-2 and HBV co-infection and 22 patients with SARS-CoV-2 and HCV co-infection. While our findings are relatively comparable with evidence from COVID-19 patients without hepatic comorbidities (10,28), our review pointed to higher morbidity and mortality among COVID-19 patients living with HBV, HCV, or both. The most common COVID-19-related symptoms were fever, cough, dyspnea, fatigue, and gastrointestinal symptoms which have also been common in COVID-19 patients without these co-infections (13,(29)(30)(31).…”

Assessing the Age Specificity of Infection Fatality Rates for COVID-19: Systematic Review, Meta-analysis, & Public Policy Implications

“…Symptoms typically develop within 6 days after exposure but may develop as early as 2 days or as late as 14 days. [1,24] More than 95% of symptomatic COVID patients have positive antibody (IgG) titres within 17-19 days of symptom onset, and those antibodies remain elevated over a sustained period. [25][26][27][28] The mean time interval from symptom onset to death is 15 days for ages 18-64 and 12 days for ages 65+, with interquartile ranges of 9-24 days and 7-19 days, respectively, while the mean interval from date of death to the reporting of that person's death is about 7 days with an IQR of 2-19 days; thus, the upper bound of the 95% confidence interval between symptom onset and reporting of fatalities is about six weeks (41 days).…”

“…Since the onset of the COVID-19 pandemic in winter 2020, it has been evident that the severity of the disease varies markedly across infected individuals. [1,2] Some remain asymptomatic throughout the course of infection or experience only mild symptoms such as headache or ageusia, whereas others experience much more severe illness, hospitalization, or even death. Thus, official case reporting may tend to encompass a high fraction of severe cases but only a small fraction of asymptomatic or mildly symptomatic cases.…”

Assessing the Age Specificity of Infection Fatality Rates for COVID-19: Systematic Review, Meta-Analysis, and Public Policy Implications

“…However, this measure can be highly misleading for SARS-CoV-2, the virus that causes COVID-19, because a high proportion of infections are asymptomatic or mildly symptomatic (especially for younger people) and may not be included in official case reports. [1,2] Consequently, the infection fatality rate (IFR), the ratio of fatalities to infections, is a more reliable metric than the CFR in assessing the hazards of COVID-19.…”