Clinical recurrences of COVID-19 symptoms after recovery: Viral relapse, reinfection or inflammatory rebound?

Abstract

Asymptomatic infection and atypical manifestations of COVID-19: Comparison of viral shedding duration Dear Editor,Coronavirus disease 2019 (COVID-19) bears several challenging problems, including insidious symptom onset, subclinical manifestations and highly transmissible property during early stage of infection. 1 In the recent study by Huang et al., SARS-CoV-2infection presented strong infectivity during the incubation period with rapid transmission. 2 Some patients with COVID-19 are asymptomatic, while others complain of atypical symptoms including loss of smell and taste sense. 3 However, there is insufficient data on the prevalence of asymptomatic infection and atypical manifestations of COVID-19. In this study, we aimed to evaluate the prevalence of asymptomatic infection, anosmia (smell loss) and ageusia (taste loss) among patients with mild COVID-19 in a residential treatment center (RTC). We also compared the duration of SARS-CoV-2 viral shedding between groups with different clinical manifestations.An observational cohort study was conducted for 199 patients with COVID-19 in a RTC at Gyeongju, Gyeongsangbuk province, Republic of Korea (ROK). The RTC was introduced to care patients with mild COVID-19 for the efficient distribution of limited medical resources during large epidemic in early March 2020. Data on demographic findings, symptoms, and duration of viral shedding were collected. The patients were interviewed about initial symptoms and their duration in detail. Real-time PCR (RT-PCR) to detect SARS-CoV-2 was performed every 2-7 days. Duration of viral shedding was considered as time from diagnosis date to the day before first negative conversion of two consecutive negative results of RT-PCR. RT-PCR was conducted using Allplex 2019-nCoV assay (Seegene, Seoul, South Korea). Statistical analyses were performed using SPSS 20.0 program. Mann-Whitney U test was performed to compare the duration of viral shedding between groups with different clinical manifestations. P -value < 0.05 was considered statistically significant. This study was approved by the Institutional Review Board of Korea University Guro Hospital (approval number: 2020GR0135).Among 199 patients with COVID-19, male was 34.7% and mean age of the patients was 38.0 years ( Table 1 ). Most patients (187, 94.0%) were healthy without chronic medical conditions. Among 199 patients, 26.6% were asymptomatic. In the early study, asymptomatic cases accounted for 10.7% (3/28) of COVID-19 cases in the ROK. 1 Asymptomatic proportion of COVID-19 was estimated as 17.9% (95% credible interval, 15.5-20.2%) on the Diamond Princess cruise ship, Japan. 4 Among clinical manifestations, cough (41.2%) was most common, followed by rhinorrhea and nasal stuffiness (30.2%). Of note, 26.1% (52/199) of patients presented anosmia, and 22.6% (45/199) complained of ageusia. Thirty-eight (19.1%) patients complained of both anosmia and ageusia. Duration of anosmia and Duration of viral shedding (days, mean ± SD) p value Asymptomatic 22.6 ± 4.0 < 0.01 * Symptomatic 25.2 ...

Predictive Factors for a New Positive Nasopharyngeal Swab Among Patients Recovered From COVID-19

“…In particular, there are no conclusive data showing how long patients with COVID-19 continue to have symptoms and test positive for the SARS-CoV-2 virus, even after 2 consecutive negative real-time reverse transcription-polymerase chain reaction (RT-PCR) tests. 5,6 The WHO criteria for hospital discharge or discontinuation of COVID-19 quarantine have been described. 7 Nevertheless, data show that some patients are positive on nasopharyngeal swab after being declared recovered, and thus the appropriate timing of ending COVID-19 quarantine remains undetermined.…”

COVID-19-Associated Suspected Myocarditis as the Etiology for Recurrent and Protracted Fever in an Otherwise Healthy Adult

“…There are few reports concerning patients tested positive for the second time – after a documented resolution of a SARS-CoV-2 infection by means of a negative PCR test, accompanied also by a clinical resolution of symptoms. 11 , 12 , 13 Conflicting evidence exist concerning the role of the initial immune response in these cases: while the immune response to SARS-CoV-2 and generation of immunoglobulins have been investigated, 14 , 15 their implications during re-exposure remain uncertain. Some studies suggest that such antibodies may play a protective role in face of re-exposure, as presented in a case report of a 69-year-old female patient, 11 and in a controlled experiment in Rhesus Macaques monkeys.…”

“…16 On the other hand, reports presenting a significant number of patients have described a second infection, with a prominent clinical presentation and a positive PCR test for SARS-CoV-2 – after resolution of the original episode, by means of both aspects. 12 , 13 Importantly, for most documented cases of such re-infection, the presence (or absence) of an acquired immune response to the primary infection was not evaluated. It is still unclear whether the immune protection following convalescence is, in some cases, insufficient, or whether an infection and resolution do not necessarily result in the acquisition of immunity.…”

Rapid Antibody-Based COVID-19 Mass Surveillance: Relevance, Challenges, and Prospects in a Pandemic and Post-Pandemic World

“…However, chances of recurrent infections of COVID-19 cannot be entirely neglected. A combination of multiple tests, including sequence comparisons of viral strains involved in multiple episodes (in the case of recurrent infections), viral culture-based methods, and determining the innate/adaptive immunity, could unravel the challenges in identifying these recurrences [ 166 ]. Hence, combining PCR results with antibody detection can possibly be a reliable means of detecting recurrent infections [ 34 ].…”