On the Prevalence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome after a SARS-CoV-2 infection

Introduction:

There is an increasing body of evidence connecting the post-acute SARS-CoV-2 condition (PASC, commonly known as long COVID) to Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), a debilitating disease of unknown cause characterized by persistent and unexplained fatigue, post-exertional malaise (PEM), among other symptoms. This connection implies that, in the clinic, some PASC cases comply with the official case definitions of ME/CFS. As such, there is a necessity to quantify the burden of ME/CFS among the PASC population in order to delineate effective healthcare interventions for the benefit of these patients who are often neglected or, in some extreme cases, stigmatized by medical staff and society.
To answer this urgent research question, Dehlia and Guthridge performed a systematic review and meta-analysis of recent data on PASC adults and reported an ME/CFS prevalence estimate of 51% (95% CI, 42%-60%); this systematic review and meta-analysis will be referred to as PASC-ME/CFS study. In the present Letter to Editor, we aimed to discuss the reliability of this estimate using the research protocol from the European Network on ME/CFS (EUROMENE) for systematic reviews and meta-analysis on the epidemiology burden of ME/CFS in Europe.

Source: Sepúlveda N, Westermeier F. On the Prevalence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome after a SARS-CoV-2 infection. J Infect. 2024 Nov 16:106353. doi: 10.1016/j.jinf.2024.106353. Epub ahead of print. PMID: 39557089. Sepúlveda N, Westermeier F. On the Prevalence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome after a SARS-CoV-2 infection. J Infect. 2024 Nov 16:106353. doi: 10.1016/j.jinf.2024.106353. Epub ahead of print. PMID: 39557089. https://www.journalofinfection.com/article/S0163-4453(24)00288-3/fulltext (Full text)

The Effect of Sex on the Risk of Long-COVID and Cardiovascular Complications in Healthy Patients without Comorbidities: Data from a Polish Long-COVID Cardiovascular (PoLoCOV-CVD) Study

Abstract:

Background: The prevalence of long-COVID (LC) presents a significant challenge to healthcare systems globally. There are still some discrepancies on the role of sex as an independent risk factor of LC complications. Thus, we aimed to determine the differences in clinical and cardiovascular complications between males and females without comorbidities after COVID-19.
Methods: Clinical data on the course of the disease with the accompanying symptoms and post-COVID-19 symptoms were compiled from both male and female subjects with a minimum 12-week interval after COVID-19 recovery. Next, the patients were followed for 12 months. ECG, echocardiography, 24 h ECG monitoring, 24 h ambulatory blood pressure monitoring (ABPM), and selected biochemical tests were performed. LC was diagnosed based on the World Health Organization (WHO) definition. To reduce the impact of confounders, i.e., body mass index (BMI) and age, on the results of the study, the nearest neighbour (NN) propensity score matching (PSM) method with a 1:1 ratio was used.
Results: The results were obtained following the removal of cases with comorbidities from the database consisting of 1237 males and 2192 females, and PSM of the new database included 886 cases (443 males and 443 females). At both the 3-month and 1-year post-recovery marks, females consistently reported a higher frequency of LC symptoms compared to males (p < 0.001 for both comparisons). Moreover, after 1 year of follow-up, females exhibited a higher prevalence of LC compared to males, with rates of 14% versus 8.3%, respectively (p = 0.013).
The symptoms that significantly differed between females and males in the 12-month follow-up were hair loss (5.4 vs. 0.7%, p < 0.001), memory and concentration disturbances (8.4 vs. 4.3%, p = 0.013), and headaches (4.3 vs. 1.4%, p = 0.008). Females presented lower mean arterial pressure (MAP) [89 (83–95) mmHg versus (vs.) 94 (89–100); p < 0.001] and lower pulse pressure (PP) [46 (42–52) mmHg vs. 51 (48–57); p < 0.001] in 24 h ABPM and more elevated heart rates (HRs) in 24 h ECG monitoring as well as arrhythmia (p < 0.001 and p = 0.018, respectively). Males had a higher occurrence of ECG abnormalities such as QRS >= 120 ms, ST-T changes, T inversion, arrhythmia, and QRS fragmentation (27.3% vs. 19.2%; p = 0.004). No significant differences were observed between males and females concerning physical activity levels, stress, fatigue, alcohol consumption, and smoking habits.
Conclusions: One year post-COVID-19 recovery, regardless of age and BMI, healthy females more often suffered from LC symptoms than males. They had lower MAP and PP in 24 h ABPM, more often had higher HRs and arrhythmia in 24 h ECG monitoring, and fewer ECG abnormalities than males.
Source: Bielecka-Dabrowa A, Sakowicz A, Gryglewska-Wawrzak K, Kapusta J, Banach M, Jankowski P, Chudzik M. The Effect of Sex on the Risk of Long-COVID and Cardiovascular Complications in Healthy Patients without Comorbidities: Data from a Polish Long-COVID Cardiovascular (PoLoCOV-CVD) Study. Journal of Clinical Medicine. 2024; 13(6):1559. https://doi.org/10.3390/jcm13061559 https://www.mdpi.com/2077-0383/13/6/1559 (Full text)

Prevalence of persistent SARS-CoV-2 in a large community surveillance study

Abstract:

Persistent SARS-CoV-2 infections may act as viral reservoirs that could seed future outbreaks1-5, give rise to highly divergent lineages6-8 and contribute to cases with post-acute COVID-19 sequelae (long COVID)9,10. However, the population prevalence of persistent infections, their viral load kinetics and evolutionary dynamics over the course of infections remain largely unknown.

Here, using viral sequence data collected as part of a national infection survey, we identified 381 individuals with SARS-CoV-2 RNA at high titre persisting for at least 30 days, of which 54 had viral RNA persisting at least 60 days. We refer to these as ‘persistent infections’ as available evidence suggests that they represent ongoing viral replication, although the persistence of non-replicating RNA cannot be ruled out in all.

Individuals with persistent infection had more than 50% higher odds of self-reporting long COVID than individuals with non-persistent infection. We estimate that 0.1-0.5% of infections may become persistent with typically rebounding high viral loads and last for at least 60 days. In some individuals, we identified many viral amino acid substitutions, indicating periods of strong positive selection, whereas others had no consensus change in the sequences for prolonged periods, consistent with weak selection. Substitutions included mutations that are lineage defining for SARS-CoV-2 variants, at target sites for monoclonal antibodies and/or are commonly found in immunocompromised people11-14. This work has profound implications for understanding and characterizing SARS-CoV-2 infection, epidemiology and evolution.

Source: Ghafari M, Hall M, Golubchik T, Ayoubkhani D, House T, MacIntyre-Cockett G, Fryer HR, Thomson L, Nurtay A, Kemp SA, Ferretti L, Buck D, Green A, Trebes A, Piazza P, Lonie LJ, Studley R, Rourke E, Smith DL, Bashton M, Nelson A, Crown M, McCann C, Young GR, Santos RAND, Richards Z, Tariq MA, Cahuantzi R; Wellcome Sanger Institute COVID-19 Surveillance Team; COVID-19 Infection Survey Group; COVID-19 Genomics UK (COG-UK) Consortium; Barrett J, Fraser C, Bonsall D, Walker AS, Lythgoe K. Prevalence of persistent SARS-CoV-2 in a large community surveillance study. Nature. 2024 Feb 21. doi: 10.1038/s41586-024-07029-4. Epub ahead of print. PMID: 38383783. https://www.nature.com/articles/s41586-024-07029-4 (Full text)

Comparing surveyed adults with long COVID and those with just a positive test helps put COVID into perspective

Abstract:

Introduction Among adults who test positive for COVID-19, some develop long COVID (symptoms lasting ≥3 months), and some do not. We compared 3 groups on selected measures to help determine strategies to reduce COVID impact.

Methods Using Stata and data for 385,617 adults from the 2022 Behavioral Risk Factor Surveillance System, we compared adults reporting long COVID, those with just a positive test, and those who never tested positive, on several health status and risk factor measures plus vaccination rates (data for 178,949 adults in 29 states).

Results Prevalence of just COVID was 26.5% (95% CI 26.2-26.8) and long COVID was 7.4% (7.3-7.6). Compared with adults with just COVID those with long COVID had worse rates for 13 of 17 measures of chronic disease, disability, and poor health status, while those with just COVID had the best results for 15 of the 17 measures among all 3 groups. The 5 risk factors (obesity, diabetes, asthma, cardiovascular disease, and COPD) previously associated with COVID deaths, increased long COVID but not just COVID rates, which were highest among younger and higher income adults. Adults with long COVID had the highest rate among the 3 groups for any COVID risk factors and data from 29 states showed they had the lowest rates for ≥3 vaccine doses of 35.6%, vs. 42.7% and 50.3% for those with just a positive test, and neither, respectively. Vaccination with ≥3 vaccines vs. <3 reduced long COVID rates by 38%, and just COVID rates by 16%.

Conclusions Results show the seriousness of long COVID vs. just a positive test and that increasing vaccine coverage by targeting adults with risk factors shows promise for reducing COVID impact.

Source: Mary L. AdamsJoseph Grandpre. Comparing surveyed adults with long COVID and those with just a positive test helps put COVID into perspective.

Prevalence and Factors Associated with Long COVID Symptoms among U.S. Adults, 2022

Abstract:

Long COVID and its symptoms have not been examined in different subpopulations of U.S. adults. Using the 2022 BRFSS (n = 445,132), we assessed long COVID and each symptom by sociodemographic characteristics and health-related variables. Multivariable logistic regression was conducted to examine factors associated with long COVID and the individual symptoms. Prevalence differences were conducted to examine differences in long COVID by vaccination status.

Overall, more than one in five adults who ever had COVID-19 reported symptoms consistent with long COVID (21.8%). The most common symptom was tiredness or fatigue (26.2%), followed by difficulty breathing or shortness of breath (18.9%), and loss of taste or smell (17.0%). Long COVID was more common among adults under 65 years, women, American Indian or Alaska Native or other/multi race group, smokers, and people with a disability, depression, overweight or obesity compared to their respective counterparts.

The prevalence of long COVID was higher among unvaccinated adults (25.6%) than vaccinated adults (21.6%) overall, and for 20 of 32 subgroups assessed. These findings underscore the benefits of vaccination, the importance of early treatment, and the need to better inform health care resource allocation and support services for those experiencing long COVID.

Source: Nguyen KH, Bao Y, Mortazavi J, Allen JD, Chocano-Bedoya PO, Corlin L. Prevalence and Factors Associated with Long COVID Symptoms among U.S. Adults, 2022. Vaccines (Basel). 2024 Jan 18;12(1):99. doi: 10.3390/vaccines12010099. PMID: 38250912; PMCID: PMC10820629. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10820629/ (Full text)

Long COVID Disability Burden in US Adults: YLDs and NIH Funding Relative to Other Conditions

Abstract:

Background Long COVID (LC) is novel, debilitating and likely chronic. Yet, scant data exist about its disability burden to guide scientific research and public health planning. We estimated Long COVID’s non-fatal disease burden in US adults and its FY2024 actual: burden-commensurate research funding from the National Institutes of Health (NIH) relative to other conditions, and biological sex.

Methods We present YLDs/100,000 for 70 NIH Research, Condition, and Disease Categories (RCDCs). Prevalence of disabling Long COVID was obtained from cross sectional surveys of representative samples of US adults, from September 2022 to August 2023. Disabling Long COVID was defined as incident symptoms persisting more than 3 months post-COVID, that significantly compromise daily activities. We calculated burden-commensurate funding for the top YLD conditions and for female vs. male dominant conditions.

Findings Disabling Long COVID was reported by 1.5% (n= 10,401) of n=757,580 respondents: Compared to the overall sample, those with disabling LC disproportionately identify as female (64.4% vs. 51.4%) and experiencing disability (80.8% vs. 52.9%) anxiety (57.5% vs. 23.8%) and depression (51.3% vs.18.5%). It ranked in the top 25% of YLDs at 320/100,000, between Alzheimer’s (279.4/100,000) and asthma (355.7/100,000) but received just 10% of its actual: YLD-commensurate funding. Only 5 conditions received less actual: burden: commensurate funding, including Myalgic Encephalitis/Chronic Fatigue Syndrome (<1%), another post-viral, female-dominant condition.

Interpretation LC has debilitated 3.8 million (weighted frequency) US adults. Research funding for it, like other female dominant conditions, lags behind its disability burden.

Research in Context Evidence before this study – We analyzed Long-COVID’s (LC) non-fatal disease burden in the US–represented by YLD (years lived with disability= prevalence x disability weight) — and National Institutes of Health (NIH) research 2024 funding relative to other conditions. We searched PubMed through 11/28/2023 for Long COVID prevalence (US), and Long COVID disability and disease burden (not US-specific). The keywords “years lived with disability” + “COVID” yielded n= 38 articles (11/29/23); but most referenced “disability-adjusted life years” (DALYs) in other countries. Similarly, “disease burden” + Long COVID yielded 23 papers, but no US YLD data. See Supplement 1 for meta-analyses, systematic reviews and US studies of Long COVID prevalence and impact.

We instead sourced YLD data from the US Census Bureau’s Household Pulse Survey (HPS) and the Institute for Health Metrics and Evaluation (IHME) /Global Burden of Disease (GBD) Long COVID Study Group. The HPS queries adults about Long COVID-related symptoms and their impact on daily activities. We applied the IHME/GBD’s estimated Long COVID disability weight of 0.21 and harmonized it with our LC case definition from the HPS data in consultation with IHME/GBD researchers. To harmonize IHME/GBD disability weights for non-LC diseases/conditions with the NIH’s terminology, we consulted with NIH staff. LC definition and measurement affects prevalence and burden estimates; our use of high-quality data sources and transparency in reporting how they were applied reduces the risk of biased assumptions.

Added value of this study- Long COVID is a chronic debilitating condition. While there is ample research on COVID’s acute illness and loss of life, there are no population-based data on its disability burden. We provide that data. To guide scientific research and public health planning, we report YLDs associated with disabling Long COVID (i.e., symptoms significantly limit activity), and; compare it to other conditions’ YLDs, NIH funding, and female-vs. male-dominance. It ranked in the top 25% of YLDs at 320/100,000, between Alzheimer’s (279.4/100,000) and asthma (355.7/100,000) but received just 10% of its YLD-commensurate funding. Only 5 conditions received less burden-commensurate funding; 3/5 were female-dominant, including Myalgic Encephalitis/Chronic Fatigue Syndrome (ME/CFS) at <1%, another post-viral condition that shares significant overlap with Long COVID. Overall, median funding/YLD was >= 5 times greater for male-vs. female-dominant conditions.

Implications of all the available evidence-Nearly 4 million US adults (weighted frequency) live with disabling Long COVID. They disproportionately identify as female and as having a disability, anxiety and depression. Yet NIH funding for diagnostic and treatment research for Long COVID hasn’t kept pace with its disability burden.

Source: Karen BonuckQi GaoSeth CongdonRyung Kim. Long COVID Disability Burden in US Adults: YLDs and NIH Funding Relative to Other Conditions.

A Mechanistic Model for Long COVID Dynamics

Abstract:

Long COVID, a long-lasting disorder following an acute infection of COVID-19, represents a significant public health burden at present. In this paper, we propose a new mechanistic model based on differential equations to investigate the population dynamics of long COVID. By connecting long COVID with acute infection at the population level, our modeling framework emphasizes the interplay between COVID-19 transmission, vaccination, and long COVID dynamics. We conducted a detailed mathematical analysis of the model. We also validated the model using numerical simulation with real data from the US state of Tennessee and the UK.

Source: Derrick J, Patterson B, Bai J, Wang J. A Mechanistic Model for Long COVID Dynamics. Mathematics (Basel). 2023 Nov;11(21):4541. doi: 10.3390/math11214541. Epub 2023 Nov 3. PMID: 38111916; PMCID: PMC10727852. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10727852/ (Full text)

Prevalence of covid-19 and long covid in collegiate student athletes from spring 2020 to fall 2021: a retrospective survey

Abstract:

Background: Symptomatic COVID-19 and Long COVID, also referred to as post-acute sequelae of SARS-CoV-2 (PASC) or post-COVID conditions, have been widely reported in young, healthy people, but their prevalence has not yet been determined in student athletes. We sought to estimate the prevalence of reported COVID-19, symptomatic COVID-19, and Long COVID in college athletes in the United States attending 18 schools from spring 2020 to fall 2021.

Methods: We developed an online survey to measure the prevalence of student athletes who tested positive for COVID-19, developed Long COVID, and did not return to their sport during the relevant time period. We surveyed a convenience sample of 18 collegiate school administrators, representing about 7,000 student athletes. Of those schools surveyed, 16 responded regarding the spring 2020 semester, and 18 responded regarding the full academic year of fall 2020 to spring 2021 (both semesters).

Results: According to the survey responses, there were 9.8% of student athletes who tested positive for COVID-19 in spring 2020 and 25.4% who tested positive in the academic year of fall 2020 to spring 2021. About 4% of student athletes who tested positive from spring 2020 to spring 2021 developed Long COVID, defined as new, recurring, or ongoing physical or mental health consequences occurring 4 or more weeks after SARS-CoV-2 infection.

Conclusions: This study highlights that Long COVID occurs among young, healthy athletes and is a real consequence of COVID-19. Understanding the prevalence of Long COVID in this population requires longer follow-up and further study.

Source: Massey D, Saydah S, Adamson B, Lincoln A, Aukerman DF, Berke EM, Sikka R, Krumholz HM. Prevalence of covid-19 and long covid in collegiate student athletes from spring 2020 to fall 2021: a retrospective survey. BMC Infect Dis. 2023 Dec 13;23(1):876. doi: 10.1186/s12879-023-08801-z. PMID: 38093182; PMCID: PMC10717379. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10717379/ (Full text)

Association between SARS-CoV-2 variants and post COVID-19 condition: findings from a longitudinal cohort study in the Belgian adult population

Abstract:

Background: While many studies on the determinants of post-COVID-19 conditions (PCC) have been conducted, little is known about the relationship between SARS-CoV-2 variants and PCC. This study aimed to assess the association between different SARS-CoV-2 variants and the probability of having PCC three months after the infection.

Methods: This study was a longitudinal cohort study conducted between April 2021 and September 2022 in Belgium. In total, 8,238 adults with a confirmed SARS-CoV-2 infection were followed up between the time of their infection and three months later. The primary outcomes were the PCC status three months post infection and seven PCC symptoms categories (neurocognitive, autonomic, gastrointestinal, respiratory, musculoskeletal, anosmia and/or dysgeusia, and other manifestations). The main exposure variable was the type of SARS-CoV-2 variants (i.e. Alpha, Delta, and Omicron), extracted from national surveillance data. The association between the different SARS-CoV-2 variants and PCC as well as PCC symptoms categories was assessed using multivariable logistic regression.

Results: The proportion of PCC among participants infected during the Alpha, Delta, and Omicron-dominant periods was significantly different and respectively 50%, 50%, and 37%. Participants infected during the Alpha- and Delta-dominant periods had a significantly higher odds of having PCC than those infected during the Omicron-dominant period (OR = 1.61, 95% confidence interval [CI] = 1.33-1.96 and OR = 1.73, 95%CI = 1.54-1.93, respectively). Participants infected during the Alpha and Delta-dominant periods were more likely to report neurocognitive, respiratory, and anosmia/dysgeusia symptoms of PCC.

Conclusions: People infected during the Alpha- and Delta-dominant periods had a higher probability of having PCC three months after infection than those infected during the Omicron-dominant period. The lower probability of PCC with the Omicron variant must also be interpreted in absolute figures. Indeed, the number of infections with the Omicron variant being higher than with the Alpha and Delta variants, it is possible that the overall prevalence of PCC in the population increases, even if the probability of having a PCC decreases.

Source: Thi Khanh HN, Cornelissen L, Castanares-Zapatero D, De Pauw R, Van Cauteren D, Demarest S, Drieskens S, Devleesschauwer B, De Ridder K, Charafeddine R, Smith P. Association between SARS-CoV-2 variants and post COVID-19 condition: findings from a longitudinal cohort study in the Belgian adult population. BMC Infect Dis. 2023 Nov 8;23(1):774. doi: 10.1186/s12879-023-08787-8. PMID: 37940843; PMCID: PMC10634063. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10634063/ (Full text)

Prevalence of Symptoms ≤12 Months After Acute Illness, by COVID-19 Testing Status Among Adults — United States, December 2020–March 2023

Summary:

What is already known about this topic? Post-COVID conditions, or long COVID, can persist for months or years after an acute COVID-19 illness and can include emergence of new symptoms or the occurrence of symptoms that come and go.

What is added by this report? In a multicenter study of adults with a COVID-like illness, symptom prevalence decreased over time after the acute illness. Approximately 16% of adults with COVID-like symptoms reported persistent symptoms 12 months after a positive or negative SARS-CoV-2 test result. At 3, 6, 9, and 12 months after testing, some symptomatic persons had ongoing symptoms, and others had emerging symptoms not reported during the previous period.

What are the implications for public health practice? Health care providers should be aware that symptoms can persist, emerge, reemerge, or resolve after COVID-like illness and are not unique to COVID-19 or to post-COVID conditions.

Abstract:

To further the understanding of post-COVID conditions, and provide a more nuanced description of symptom progression, resolution, emergence, and reemergence after SARS-CoV-2 infection or COVID-like illness, analysts examined data from the Innovative Support for Patients with SARS-CoV-2 Infections Registry (INSPIRE), a prospective multicenter cohort study. This report includes analysis of data on self-reported symptoms collected from 1,296 adults with COVID-like illness who were tested for SARS-CoV-2 using a Food and Drug Administration–approved polymerase chain reaction or antigen test at the time of enrollment and reported symptoms at 3-month intervals for 12 months.

Prevalence of any symptom decreased substantially between baseline and the 3-month follow-up, from 98.4% to 48.2% for persons who received a positive SARS-CoV-2 test results (COVID test–positive participants) and from 88.2% to 36.6% for persons who received negative SARS-CoV-2 test results (COVID test–negative participants).

Persistent symptoms decreased through 12 months; no difference between the groups was observed at 12 months (prevalence among COVID test–positive and COVID test–negative participants = 18.3% and 16.1%, respectively; p>0.05).

Both groups reported symptoms that emerged or reemerged at 6, 9, and 12 months. Thus, these symptoms are not unique to COVID-19 or to post-COVID conditions. Awareness that symptoms might persist for up to 12 months, and that many symptoms might emerge or reemerge in the year after COVID-like illness, can assist health care providers in understanding the clinical signs and symptoms associated with post-COVID–like conditions.

Source: Montoy JC, Ford J, Yu H, et al. Prevalence of Symptoms ≤12 Months After Acute Illness, by COVID-19 Testing Status Among Adults — United States, December 2020–March 2023. MMWR Morb Mortal Wkly Rep 2023;72:859–865. DOI: http://dx.doi.org/10.15585/mmwr.mm7232a2 (Full text)