With repeated positivity being an undiscovered and major concern, we aimed to evaluate
which prognostic factors may impact repeated SARS-CoV-2 positivity (RSP) and their
association with immunoglobulin detectability among recovered patients. A systematic
literature search was performed on 5 April 2021. Cohort studies with risk factors
for repeated RSP or information about the immunoglobulin response (immunoglobulin
M (IgM) and/or immunoglobulin G (IgG)) were included in this analysis. The main examined
risk factors were severity of the initial infection, body mass index (BMI), length
of hospitalization (LOH), age, and gender, for which we pooled mean differences and
odds ratios (ORs). Thirty-four cohort studies (N = 9269) were included in our analysis.
We found that increased RSP rate might be associated with IgG positivity; IgG presence
was higher in RSP patients (OR: 1.72, CI: 0.87–3.41, p = 0.117). Among the examined
risk factors, only mild initial disease course showed a significant association with
RSP (OR: 0.3, CI: 0.14–0.67, p = 0.003). Age, male gender, BMI, LOH, and severity
of the first episode do not seem to be linked with repeated positivity. However, further
prospective follow-up studies focusing on this topic are required.
