Long-COVID Rates Vary Throughout the SARS-CoV-2 Pandemic

Abstract:

The infection with Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) frequently causes a broad range of long-lasting symptoms. This condition, termed long-COVID, influences everyday life of affected individuals in many ways and causes a high economic burden. There is urgent need to obtain better understanding of the risk factors that contribute to the development of long-COVID.

Aim of this study was to investigate the long-COVID rate of supposedly healthy adults during different phases of the pandemic. Therefore, 71,670 blood donations were screened for SARS-CoV-2 total anti-N antibodies between 5 th June 2020 and 30 th November 2022. 351 individuals could be recruited for our study to monitor long-COVID symptoms and their duration. Despite immense worldwide efforts to stop virus dissemination, our data reveal a constantly rising SARS-CoV-2 anti-N seroprevalence rate in Salzburg, Austria, peaking at 84.9% in October 2022.

In addition, our data demonstrate varying rates of long-COVID in the course of the pandemic. While long-COVID rates were about 20% for the time span between March 2020 and August 2021, long-COVID was reported by 12% for infections from September 2021 to August 2022. This could be attributed to different virus variants, but also to increasing vaccination rates. We further found that long-COVID symptoms decline over time: while 18% of our study participants described persisting symptoms 3 months after the seropositive blood donation, 14% reported persisting symptoms 9 months afterwards and 3% after 18 months.

In conclusion, our data reveal that long-COVID symptoms may persist for more than a year after a SARS-CoV-2 infection and that long-COVID rates are varying in the course of the SARS-CoV-2 pandemic.

Source: Nunhofer, et al. Long-COVID Rates Vary Throughout the SARS-CoV-2 Pandemic. Journal of Infectious Diseases & Therapy. Volume 11 • Issue 01 • 1000520. ISSN: 2332-0877.  https://www.researchgate.net/profile/Sandra-Laner-Plamberger/publication/368293143_Long-COVID_Rates_Vary_Throughout_the_SARS-CoV-2_Pandemic/links/63e0dd9062d2a24f920a4d24/Long-COVID-Rates-Vary-Throughout-the-SARS-CoV-2-Pandemic.pdf (Full text)

Impact of COVID-19 vaccination in post-COVID cardiac complications

Abstract:

Background: After the acute infection, COVID-19 can produce cardiac complications as well as long-COVID persistent symptoms. Although vaccination against COVID-19 represented a clear reduction in both mortality and ICU admissions, there is very little information on whether this was accompanied by a decrease in the prevalence of post-COVID cardiac complications. The aim of this study was to analyze the relationship between COVID-19 vaccination and the prevalence of post-COVID cardiac injury assessed by echocardiogram, and long-COVID persistent cardiac symptoms.

Methods: All patients who consulted for post-COVID evaluation 14 days after discharge from acute illness were included. Patients with heart disease were excluded. The relationship between complete vaccination scheme (at least two doses applied with 14 days or more since the last dose) and pathological echocardiographic findings, as well as the relationship of vaccination with persistent long-COVID symptoms, were evaluated by multivariate analysis, adjusting for age, sex and clinical variables that would have shown significant differences in univariate analysis.

Results: From 1883 patients, 1070 patients (56.8%) suffered acute COVID-19 without a complete vaccination scheme. Vaccination was associated with lower prevalence of cardiac injury (1.35% versus 4.11%, adjusted OR 0.33; 95% CI 0.17-0.65, p=0.01). In addition, vaccinated group had a lower prevalence of persistent long-COVID symptoms compared to unvaccinated patients (10.7% versus 18.3%, adjusted OR 0.52; 95% CI 0.40-0.69, p<0.001).

Conclusion: Vaccination against COVID-19 was associated with lower post-COVID cardiac complications and symptoms, reinforcing the importance of fully vaccinating the population.

Source: Parodi JB, Indavere A, Bobadilla Jacob P, Toledo GC, Micali RG, Waisman G, Masson W, Epstein ED, Huerin MS. Impact of COVID-19 vaccination in post-COVID cardiac complications. Vaccine. 2023 Feb 17;41(8):1524-1528. doi: 10.1016/j.vaccine.2023.01.052. Epub 2023 Jan 27. PMID: 36725436; PMCID: PMC9885297. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9885297/ (Full text)

Protective effect of COVID-19 vaccination against long COVID syndrome: A systematic review and meta-analysis

Abstract:

Background: The relationship between coronavirus disease 2019 (COVID-19) vaccination and long COVID has not been firmly established. We conducted a systematic review and meta-analysis to evaluate the association between COVID-19 vaccination and long COVID.

Methods: PubMed and EMBASE databases were searched on September 2022 without language restrictions (CRD42022360399) to identify prospective trials and observational studies comparing patients with and without vaccination before severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. We also included studies reporting symptomatic changes of ongoing long COVID following vaccination among those with a history of SARS-CoV-2 infection. Odds ratios (ORs) for each outcome were synthesized using a random-effects model. Symptomatic changes after vaccination were synthesized by a one-group meta-analysis.

Results: Six observational studies involving 536,291 unvaccinated and 84,603 vaccinated (before SARS-CoV-2 infection) patients (mean age, 41.2-66.6; female, 9.0-67.3%) and six observational studies involving 8,199 long COVID patients (mean age, 40.0 to 53.5; female, 22.2-85.9%) who received vaccination after SARS-CoV-2 infection were included. Two-dose vaccination was associated with a lower risk of long COVID compared to no vaccination (OR, 0.64; 95% confidence interval [CI], 0.45-0.92) and one-dose vaccination (OR, 0.60; 95% CI, 0.43-0.83). Two-dose vaccination compared to no vaccination was associated with a lower risk of persistent fatigue (OR, 0.62; 95% CI, 0.41-0.93) and pulmonary disorder (OR, 0.50; 95% CI, 0.47-0.52). Among those with ongoing long COVID symptoms, 54.4% (95% CI, 34.3-73.1%) did not report symptomatic changes following vaccination, while 20.3% (95% CI, 8.1-42.4%) experienced symptomatic improvement after two weeks to six months of COVID-19 vaccination.

Conclusions: COVID-19 vaccination before SARS-CoV-2 infection was associated with a lower risk of long COVID, while most of those with ongoing long COVID did not experience symptomatic changes following vaccination.

Source: Watanabe A, Iwagami M, Yasuhara J, Takagi H, Kuno T. Protective effect of COVID-19 vaccination against long COVID syndrome: A systematic review and meta-analysis. Vaccine. 2023 Feb 8:S0264-410X(23)00134-2. doi: 10.1016/j.vaccine.2023.02.008. Epub ahead of print. PMID: 36774332; PMCID: PMC9905096. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9905096/ (Full text)

Persistent short nighttime sleep duration is associated with a greater post-COVID risk in fully mRNA-vaccinated individuals

Abstract:

Short nighttime sleep duration impairs the immune response to virus vaccination, and long nighttime sleep duration is associated with poor health status. Thus, we hypothesized that short (<6 h) and long (>9 h) nighttime sleepers have a higher post-COVID risk than normal nighttime sleepers, despite two doses of mRNA vaccine (which has previously been linked to lower odds of long-lasting COVID-19 symptoms). Post-COVID was defined as experiencing at least one core COVID-19 symptom for at least three months (e.g., shortness of breath).

Multivariate logistic regression adjusting for age, sex, BMI, and other factors showed in 9717 respondents (age span 18-99) that two mRNA vaccinations lowered the risk of suffering from post-COVID by about 21% (p < 0.001). When restricting the analysis to double-vaccinated respondents (n = 5918), short and long sleepers exhibited a greater post-COVID risk than normal sleepers (adjusted OR [95%-CI], 1.56 [1.29, 1.88] and 1.87 [1.32, 2.66], respectively). Among respondents with persistent sleep duration patterns during the pandemic compared to before the pandemic, short but not long sleep duration was significantly associated with the post-COVID risk (adjusted OR [95%-CI], 1.59 [1.24, 2.03] and 1.18 [0.70, 1.97], respectively). No significant association between sleep duration and post-COVID symptoms was observed in those reporting positive SARS-CoV-2 test results (n = 538).

Our findings suggest that two mRNA vaccinations against SARS-CoV-2 are associated with a lower post-COVID risk. However, this protection may be less pronounced among those sleeping less than 6 h per night. Our findings warrant replication in cohorts with individuals with confirmed SARS-CoV-2 infection.

Source: Xue P, Merikanto I, Chung F, Morin CM, Espie C, Bjorvatn B, Cedernaes J, Landtblom AM, Penzel T, De Gennaro L, Holzinger B, Matsui K, Hrubos-Strøm H, Korman M, Leger D, Mota-Rolim S, Bolstad CJ, Nadorff M, Plazzi G, Reis C, Chan RNY, Wing YK, Yordanova J, Bjelajac AK, Inoue Y, Partinen M, Dauvilliers Y, Benedict C. Persistent short nighttime sleep duration is associated with a greater post-COVID risk in fully mRNA-vaccinated individuals. Transl Psychiatry. 2023 Feb 1;13(1):32. doi: 10.1038/s41398-023-02334-4. PMID: 36726008; PMCID: PMC9890416. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9890416/ (Full text)

Severe Fatigue and Persistent Symptoms at Three Months Following SARS-CoV-2 Infections During the Pre-Delta, Delta, and Omicron Time Periods: A Multicenter Prospective Cohort Study

Abstract:

Background: Most research on SARS-CoV-2 variants focuses on initial symptomatology with limited data on longer-term sequelae. We sought to characterize the prevalence and differences in prolonged symptoms at three months post SARS-CoV-2-infection across the three major variant time-periods (pre-Delta, Delta, and Omicron).

Methods: This multicenter prospective cohort study of adults with acute illness tested for SARS-CoV-2 compared fatigue severity, fatigue symptoms, individual and organ system-based symptoms, and presence of ≥3 total symptoms across variants among COVID-positive and COVID-negative participants 3 months after their initial SARS-CoV-2 diagnosis. Variant periods were defined by dates with ≥50% dominant strain. We performed a sensitivity analysis using ≥90% dominance threshold and multivariable logistic regression modeling to estimate the independent effects of each variant adjusting for socio-demographic characteristics, baseline health, and vaccine status.

Results: The study included 3,223 participants (2,402 COVID-positive and 821 COVID-negative). Among the COVID-positive cohort, 463 (19.3%) were pre-Delta, 1,198 (49.9%) during Delta, and 741 (30.8%) during Omicron. Prolonged severe fatigue was highest in the pre-Delta COVID-positive cohort compared with Delta and Omicron cohorts (16.7% vs 11.5% vs 12.3%, respectively; p = 0.017), as was presence of ≥3 prolonged symptoms (28.4% vs 21.7% vs 16.0%; p < 0.001). No difference was seen in the COVID-negative cohort between variant time-periods. In multivariable models, there was no difference in severe fatigue between variants. There was decreased odds of having ≥3 symptoms in Omicron compared with other variants; this was not significant after adjusting for vaccination status.

Conclusions: Prolonged symptoms following SARS-CoV-2 infection were more common among participants infected during the pre-Delta period compared with Delta and Omicron periods; however, these differences were no longer significant after adjusting for vaccination status. This suggests a potential beneficial effect of vaccination on the risk of developing long-term symptoms.

Source: Gottlieb M, Wang R, Yu H, Spatz ES, Montoy JC, Rodriguez R, Chang AM, Elmore JG, Hannikainen PA, Hill M, Huebinger RM, Idris AH, Lin Z, Koo K, McDonald S, O’Laughlin KN, Plumb ID, Santangelo M, Saydah S, Willis M, Wisk LE, Venkatesh A, Stephens KA, Weinstein RA; INSPIRE Group. Severe Fatigue and Persistent Symptoms at Three Months Following SARS-CoV-2 Infections During the Pre-Delta, Delta, and Omicron Time Periods: A Multicenter Prospective Cohort Study. Clin Infect Dis. 2023 Jan 27:ciad045. doi: 10.1093/cid/ciad045. Epub ahead of print. PMID: 36705268.  https://pubmed.ncbi.nlm.nih.gov/36705268/ (Full study available as PDF file)

Epidemiology, symptomatology, and risk factors for long COVID symptoms: Multi-centre study

Abstract:

Background: Long COVID induces a substantial global burden of disease. The pathogenesis, complications, epidemiological and clinical characteristics of COVID-19 patients in the acute phase have been evaluated, while few studies have characterized the epidemiology, symptomatology and risk factors of long COVID symptoms. Its characteristics among coronavirus disease 2019 (COVID-19) patients in the general population remain unaddressed.

Objective: We examined the prevalence of long COVID symptoms, its symptom patterns, and its risk factors. we aimed to fill the knowledge gaps by evaluating the prevalence of long COVID symptoms in four major Chinese cities.

Methods: We performed a population-based, multi-centre survey by a representative sampling strategy via the Qualtrics platform in Beijing, Shanghai, Guangzhou and Hong Kong (June 2022). We included 2,712 community-dwelling, COVID-19 patients, and measured the prevalence of long COVID symptoms defined by the WHO, and their risk factors. The primary outcomes were the symptoms of long COVID with various levels of impact. A descriptive analysis was conducted on the prevalence and distribution of the long COVID symptoms according to disease severity. A sensitivity analysis of increasing the number of long COVID symptoms was also conducted. A univariate and multivariate regression analysis was performed to examine the risk factors of severe long COVID symptoms, including age, gender, marital status, current occupation, educational level, living status, smoking habits, monthly household income, self-perceived health status, presence of chronic diseases, use of chronic medication, COVID-19 vaccination status, and severity of COVID-19.

Results: The response rate was 63.6%. The prevalence of long COVID, moderate or severe long COVID, and severe long COVID was 90.4%, 62.4%, and 31.0%, respectively. Fatigue (33.7%), cough (31.9%), sore throat (31.0%), difficulty in concentration (30.5%), feeling of anxiety (30.2%), myalgia (29.9%), and arthralgia (29.9%) were the most common severe long COVID symptoms. From multivariate regression analysis, female gender (adjusted odds ratio [aOR]=1.49, 95% C.I.=1.13-1.95), engagement in transportation, logistics, or discipline workforce (aOR=2.52, 95% C.I.=1.58-4.03), living with domestic workers (aOR=2.37, 95% C.I.=1.39-4.03), smoking (aOR=1.55, 95% C.I.=1.17-2.05), poor self-perceived health status (aOR 5.06 to 15.38), chronic diseases (aOR 1.92 to 2.71), chronic medication use (aOR=4.38, 95% C.I.=1.66-11.53), and critical severity of COVID-19 (aOR=1.52, 95% C.I.=1.07-2.15) were associated with severe long COVID. Prior vaccination for ≥2 doses of COVID-19 was a protective factor (aOR=0.35-0.22, 95% C.I.=0.08-0.90).

Conclusions: We have examined the prevalence of long COVID symptoms in four Chinese cities according to the severity of COVID-19. We also evaluated the pattern of long COVID symptoms, and their risk factors. These findings may inform early identification of COVID-19 patients at risk of long COVID and planning of rehabilitative services.

Source: Wong MC, Huang J, Wong NY, Wong GL, Yip TC, Chan RN, Chau SW, Ng SC, Wing YK, Chan FK. Epidemiology, symptomatology, and risk factors for long COVID symptoms: Multi-centre study. JMIR Public Health Surveill. 2023 Jan 12. doi: 10.2196/42315. Epub ahead of print. PMID: 36645453. https://pubmed.ncbi.nlm.nih.gov/36645453/

Long COVID Symptomatology and Associated Factors in Primary Care Patients: The EPICOVID-AP21 Study

Abstract:

Persistent COVID-19 condition includes a wide variety of symptoms and health problems of indeterminate duration. The present study examined the sociodemographic and clinical characteristics of the population with Long COVID seen in Primary Care using a questionnaire based on the existing scientific literature. It was an observational and descriptive study of the characteristics of the Spanish population with Long COVID over 14 years of age.
The responses were analysed by means of a descriptive analysis of the variables recorded, in addition to a bivariate analysis to determine the existence of a relationship between persistent COVID-19 and variables such as gender, age, vaccination status or concomitant pathology. The results obtained clearly describe the sociodemographic characteristics of the population, highlighting the predominance of female gender and the prevalence of tiredness and fatigue.
Furthermore, relevant information was obtained on the differences in symptomatology according to gender, age, previous pathologies and alterations derived from infection and/or vaccination. These data are important for better detection, diagnosis and treatment of Long COVID and the improvement of the quality of life of this population.
Source: Romero-Rodríguez E, Perula-de-Torres LÁ, González-Lama J, Castro-Jiménez RÁ, Jiménez-García C, Priego-Pérez C, Vélez-Santamaría R, Simón-Vicente L, González-Santos J, González-Bernal JJ. Long COVID Symptomatology and Associated Factors in Primary Care Patients: The EPICOVID-AP21 Study. Healthcare. 2023; 11(2):218. https://doi.org/10.3390/healthcare11020218 https://www.mdpi.com/2227-9032/11/2/218 (Full text)

Long covid outcomes at one year after mild SARS-CoV-2 infection: nationwide cohort study

Abstract:

Objectives: To determine the clinical sequelae of long covid for a year after infection in patients with mild disease and to evaluate its association with age, sex, SARS-CoV-2 variants, and vaccination status.

Design: Retrospective nationwide cohort study.

Setting: Electronic medical records from an Israeli nationwide healthcare organisation.

Population: 1 913 234 Maccabi Healthcare Services members of all ages who did a polymerase chain reaction test for SARS-CoV-2 between 1 March 2020 and 1 October 2021.

Main outcome measures: Risk of an evidence based list of 70 reported long covid outcomes in unvaccinated patients infected with SARS-CoV-2 matched to uninfected people, adjusted for age and sex and stratified by SARS-CoV-2 variants, and risk in patients with a breakthrough SARS-CoV-2 infection compared with unvaccinated infected controls. Risks were compared using hazard ratios and risk differences per 10 000 patients measured during the early (30-180 days) and late (180-360 days) time periods after infection.

Results: Covid-19 infection was significantly associated with increased risks in early and late periods for anosmia and dysgeusia (hazard ratio 4.59 (95% confidence interval 3.63 to 5.80), risk difference 19.6 (95% confidence interval 16.9 to 22.4) in early period; 2.96 (2.29 to 3.82), 11.0 (8.5 to 13.6) in late period), cognitive impairment (1.85 (1.58 to 2.17), 12.8, (9.6 to 16.1); 1.69 (1.45 to 1.96), 13.3 (9.4 to 17.3)), dyspnoea (1.79 (1.68 to 1.90), 85.7 (76.9 to 94.5); 1.30 (1.22 to 1.38), 35.4 (26.3 to 44.6)), weakness (1.78 (1.69 to 1.88), 108.5, 98.4 to 118.6; 1.30 (1.22 to 1.37), 50.2 (39.4 to 61.1)), and palpitations (1.49 (1.35 to 1.64), 22.1 (16.8 to 27.4); 1.16 (1.05 to 1.27), 8.3 (2.4 to 14.1)) and with significant but lower excess risk for streptococcal tonsillitis and dizziness. Hair loss, chest pain, cough, myalgia, and respiratory disorders were significantly increased only during the early phase. Male and female patients showed minor differences, and children had fewer outcomes than adults during the early phase of covid-19, which mostly resolved in the late period. Findings remained consistent across SARS-CoV-2 variants. Vaccinated patients with a breakthrough SARS-CoV-2 infection had a lower risk for dyspnoea and similar risk for other outcomes compared with unvaccinated infected patients.

Conclusions: This nationwide study suggests that patients with mild covid-19 are at risk for a small number of health outcomes, most of which are resolved within a year from diagnosis.

Source: Mizrahi B, Sudry T, Flaks-Manov N, Yehezkelli Y, Kalkstein N, Akiva P, Ekka-Zohar A, Ben David SS, Lerner U, Bivas-Benita M, Greenfeld S. Long covid outcomes at one year after mild SARS-CoV-2 infection: nationwide cohort study. BMJ. 2023 Jan 11;380:e072529. doi: 10.1136/bmj-2022-072529. PMID: 36631153; PMCID: PMC9832503. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9832503/ (Full text)

Clinical Characteristics in the Acute Phase of COVID-19 That Predict Long COVID: Tachycardia, Myalgias, Severity, and Use of Antibiotics as Main Risk Factors, While Education and Blood Group B Are Protective

Abstract:

Background: Risk factors for developing long COVID are not clearly established. The present study was designed to determine if any sign, symptom, or treatment of the acute phase, or personal characteristics of the patient, is associated with the development of long COVID.
Methods: A cohort study was carried out, randomly selecting symptomatic COVID-19 patients and not vaccinated. The severity of the acute illness was assessed through the number of compatible COVID-19 symptoms, hospitalizations, and the symptom severity score using a 10-point visual analog scale.
Results: After multivariate analysis, a severity score ≥8 (RR 2.0, 95%CI 1.1–3.5, p = 0.022), hospitalization (RR 2.1, 95%CI 1.0–4.4, p = 0.039), myalgia (RR 1.9, 95%CI 1.08–3.6, p = 0.027), tachycardia (RR 10.4, 95%CI 2.2–47.7, p = 0.003), and use of antibiotics (RR 2.0, 95%CI 1.1–3.5, p = 0.022), was positively associated with the risk of having long COVID. Higher levels of education (RR 0.6, 95%CI 0.4–0.9, p = 0.029) and type positive B blood group (B + AB, RR 0.44, 95%CI 0.2–0.9, p = 0.044) were protective factors. The most important population attributable fractions (PAFs) for long COVID were myalgia (37%), severity score ≥8 (31%), and use of antibiotics (27%).
Conclusions: Further studies in diverse populations over time are needed to expand the knowledge that could lead us to prevent and/or treat long COVID.
Source: Guzman-Esquivel J, Mendoza-Hernandez MA, Guzman-Solorzano HP, Sarmiento-Hernandez KA, Rodriguez-Sanchez IP, Martinez-Fierro ML, Paz-Michel BA, Murillo-Zamora E, Rojas-Larios F, Lugo-Trampe A, Plata-Florenzano JE, Delgado-Machuca M, Delgado-Enciso I. Clinical Characteristics in the Acute Phase of COVID-19 That Predict Long COVID: Tachycardia, Myalgias, Severity, and Use of Antibiotics as Main Risk Factors, While Education and Blood Group B Are Protective. Healthcare. 2023; 11(2):197. https://doi.org/10.3390/healthcare11020197 https://www.mdpi.com/2227-9032/11/2/197 (Full text)

Characteristics and predictors of Long COVID among diagnosed cases of COVID-19

Abstract:

Background: Long COVID or long-term symptoms after COVID-19 has the ability to affect health and quality of life. Knowledge about the burden and predictors could aid in their prevention and management. Most of the studies are from high-income countries and focus on severe acute COVID-19 cases. We did this study to estimate the incidence and identify the characteristics and predictors of Long COVID among our patients.

Methodology: We recruited adult (≥18 years) patients who were diagnosed as Reverse Transcription Polymerase Chain Reaction (RTPCR) confirmed SARS-COV-2 infection and were either hospitalized or tested on outpatient basis. Eligible participants were followed up telephonically after four weeks and six months of diagnosis of SARS-COV-2 infection to collect data on sociodemographic, clinical history, vaccination history, Cycle threshold (Ct) values during diagnosis and other variables. Characteristics of Long COVID were elicited, and multivariable logistic regression was done to find the predictors of Long COVID.

Results: We have analyzed 487 and 371 individual data with a median follow-up of 44 days (Inter quartile range (IQR): 39,47) and 223 days (IQR:195,251), respectively. Overall, Long COVID was reported by 29.2% (95% Confidence interval (CI): 25.3%,33.4%) and 9.4% (95% CI: 6.7%,12.9%) of participants at four weeks and six months of follow-up, respectively. Incidence of Long COVID among patients with mild/moderate disease (n = 415) was 23.4% (95% CI: 19.5%,27.7%) as compared to 62.5% (95% CI: 50.7%,73%) in severe/critical cases(n = 72) at four weeks of follow-up. At six months, the incidence among mild/moderate (n = 319) was 7.2% (95% CI:4.6%,10.6%) as compared to 23.1% (95% CI:12.5%,36.8%) in severe/critical (n = 52). The most common Long COVID symptom was fatigue. Statistically significant predictors of Long COVID at four weeks of follow-up were-Pre-existing medical conditions (Adjusted Odds ratio (aOR) = 2.00, 95% CI: 1.16,3.44), having a higher number of symptoms during acute phase of COVID-19 disease (aOR = 11.24, 95% CI: 4.00,31.51), two doses of COVID-19 vaccination (aOR = 2.32, 95% CI: 1.17,4.58), the severity of illness (aOR = 5.71, 95% CI: 3.00,10.89) and being admitted to hospital (Odds ratio (OR) = 3.89, 95% CI: 2.49,6.08).

Conclusion: A considerable proportion of COVID-19 cases reported Long COVID symptoms. More research is needed in Long COVID to objectively assess the symptoms and find the biological and radiological markers.

Source: Arjun MC, Singh AK, Pal D, Das K, G A, Venkateshan M, Mishra B, Patro BK, Mohapatra PR, Subba SH. Characteristics and predictors of Long COVID among diagnosed cases of COVID-19. PLoS One. 2022 Dec 20;17(12):e0278825. doi: 10.1371/journal.pone.0278825. PMID: 36538532; PMCID: PMC9767341. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9767341/ (Full text)