These symptoms and risk factors may predict whether you could become a ‘COVID-19 long hauler,’ study suggests

Authors: Adrianna Rodriguez USA TODAY March 11, 2021

A new study suggests coronavirus symptoms felt in the first week of infection may be a predictor of how long they will last.

Patients with COVID-19 who felt more than five symptoms in their first week of illness were more likely to become a “COVID-19 long hauler,” which researchers qualified as having symptoms for longer than 28 days, according to the study published Wednesday in the peer-reviewed journal Nature Medicine.

The five symptoms experienced during the first week that were most predictive of becoming a long hauler were fatigue, headache, hoarse voice, muscle pain and difficulty breathing.

Researchers from King’s College London, Massachusetts General Hospital and Boston Children’s Hospital asked COVID-19 patients from the U.K., U.S. and Sweden to report their symptoms through a smartphone application from March to September 2020.

Out of more than 4,000 participants, about 13% of patients reported symptoms lasting more than 28 days, 4% for more than 8 weeks and 2% more than 12 weeks.

Out of the patients who reported symptoms for more than four weeks, “a third of those will have symptoms at 8 weeks and then a third of those at 12 weeks,” said study co-author Dr. Christina Astley, a physician scientist at Boston Children’s Hospital. “If you think about it, 1 in 20 people who have COVID-19 will have symptoms lasting 8 weeks or more.” 

The likelihood of having persistent symptoms was significantly associated with increasing age, rising from 9.9% of individuals 18 to 49, to 21.9% in those above 70. Anosmia, or the loss of smell, was the most common symptom in older age groups.

Women also were more likely to have long COVID-19 than men, with 14.9% of female study participants reporting symptoms 28 days after initial infection, compared with 9.5% of men.

While the study attempted to identify risk factors and markers that may indicate long COVID-19, doctors are finding it can happen to anyone at any age, said Dr. Michael Wechsler, a pulmonologist at National Jewish Health.

“It can happen in any age group, but it’s most alarming to younger people who are otherwise healthy and not used to these symptoms,” he said.

COVID long haulers:Dr. Anthony Fauci aims to answer ‘a lot of important questions’ in new nationwide initiative

The study found two main patterns among study participants. One group of COVID-19 long haulers exclusively reported fatigue, headache and upper respiratory issues, such as shortness of breath, sore throat, cough and loss of smell. However, a second group of long haulers had persistent multi-system complaints, such as a fever or gastrointestinal symptoms.

Weschler sees a wide array of symptoms in the clinic that caters to COVID-19 long haulers at National Jewish Health. Similar clinics have popped up in hospitals across the country to accommodate the growing number of COVID-19 patients who report symptoms months after recovery.

“Long COVID is common. It affects a large proportion of patients and has a wide distribution of symptoms,” he said. “It’s important to make people aware that all these different side effects and symptoms can occur.”

The study comes a few weeks after Dr. Anthony Fauci announced the U.S. government was launching nationwide initiative to study long COVID-19, which he called Post Acute Sequelae of SARS-CoV-2 (PASC).

A study published in JAMA Network Open on Feb. 19 found that about 30% of COVID-19 patients reported persistent symptoms as long as nine months after illness.

“(There are) a lot of important questions that are now unanswered that we hope with this series of initiatives we will ultimately answer,” he said during a White House briefing Feb. 24.

Link between fever, diarrhea, severe COVID-19, and persistent anti-SARS-CoV-2 antibodies

Authors: By Dr. Liji Thomas, MD Jan 7 2021

Ever since the coronavirus disease 2019 (COVID-19) pandemic began, there have been many attempts to understand the nature and duration of immunity against the causative agent, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

A new preprint research paper appearing on the medRxiv* server describes a link between the persistence of neutralizing antibodies against the virus, disease severity, and specific COVID-19 symptoms.

Permanent immunity is essential if the pandemic is to end. In the earlier SARS epidemic, antibodies were found to last for three or more years after infection in most patients. With the current virus, it may last for six or more months at least, as appears from some reports. Other researchers have concluded that immunity wanes rapidly over the same period, with some patients who were tested positive for antibodies becoming seronegative later on. This discrepancy may be traceable to variation in testing methods, sample sizes and testing time points, as well as disease severity.

Study details

The current study looked at a population of over a hundred convalescent COVID-19 patients, testing most of them for antibodies at five weeks and three months from symptom resolution.

The researchers used a multiplex assay that measured the Immunoglobulin G (IgG) levels against four SARS-CoV-2 antigens, one from SARS-CoV, and four from circulating seasonal coronaviruses. In addition, they carried out an inhibition assay against SARS-CoV-2 spike receptor-binding domain (RBD)-angiotensin-converting enzyme 2 (ACE2) binding and a neutralization assay against the virus. The antibody titers were then plotted against various clinical features and demographic factors.

Antibody titers higher in COVID-19 convalescents

The researchers found that severe disease is correlated with advanced age and the male sex. Patients with underlying vascular disease were more likely to be hospitalized with COVID-19, but those with asthma were relatively spared.

Convalescent COVID-19 patients had higher IgG levels against all four SARS-CoV-2 antigens, relative to controls, and in 98% of cases, at least one of the tests was likely to show higher binding compared to controls. IgGs targeting the viral spike and RBD were likely to be much more discriminatory between SARS-CoV-2 patients and controls. Interestingly, anti-SARS-CoV IgG, as well as anti-seasonal betacoronavirus antibodies, were likely to be higher in these patients.

Anti-spike and anti-nucleocapsid IgG levels, as well as neutralizing antibody titers, were higher in convalescent hospitalized COVID-19 patients than in convalescent non-hospitalized patients, and the titers were positively associated with disease severity.Antibodies against SARS-CoV-2 persist three months after COVID-19 symptom resolution. Sera from COVID-19 convalescent subjects (n=79) collected 5 weeks (w) and 3 months (m) after symptom resolution were subjected to multiplex assay to detect IgG that binds to SARS-CoV-2 S, NTD, RBD and N antigens (A), to RBD-ACE2 binding inhibition assay (B), and to SARS-CoV-2 neutralization assay (C). Dots, lines, and asterisks in red represent non-hospitalized (n=67) and in blue represent hospitalized (n=12) subjects with lines connecting the two time points for individual subjects (*p<0.05 and **p<0.01 by paired t test).Antibodies against SARS-CoV-2 persist three months after COVID-19 symptom resolution. Sera from COVID-19 convalescent subjects (n=79) collected 5 weeks (w) and 3 months (m) after symptom resolution were subjected to multiplex assay to detect IgG that binds to SARS-CoV-2 S, NTD, RBD and N antigens (A), to RBD-ACE2 binding inhibition assay (B), and to SARS-CoV-2 neutralization assay (C). Dots, lines, and asterisks in red represent non-hospitalized (n=67) and in blue represent hospitalized (n=12) subjects with lines connecting the two time points for individual subjects (*p<0.05 and **p<0.01 by paired t test).

Clinical correlates of higher antibody titer

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When antibody titers in non-hospitalized subjects were compared with clinical and demographic variables, they found that older males with a higher body mass index (BMI) and a Charlson Comorbidity Index score >2 were likely to have higher antibody titers. COVID-19 symptoms that correlated with higher antibody levels in these patients comprise fever, diarrhea, abdominal pain and loss of appetite. Chest tightening, headache and sore throat were associated with less severe symptoms.

The link between the specific symptoms listed above with higher antibody titers could indicate that they mark a robust systemic inflammatory response, which in turn is necessary for a strong antibody response. Diarrhea may mark severe disease, but it is strange that in this case, it was not more frequent in the hospitalized cohort. Alternatively, diarrhea may have strengthened the immune antibody response via the exposure of the virus to more immune cells via the damaged enteric mucosa. More study is required to clarify this finding.

Potential substitute for neutralizing assay

The binding assay showed that the convalescent serum at five weeks inhibited RBD-ACE2 binding much more powerfully than control serum. Neutralizing activity was also higher in these sera, but in 15% of cases, convalescent patients showed comparable neutralizing antibody titers to those in control sera. On the whole, however, there was a positive association between neutralizing antibody titer, anti-SARS-CoV-2 IgG titers, and inhibition of ACE2 binding.

Persistent immunity at three months

This study also shows that SARS-CoV-2 antibodies persist in these patients at even three months after symptoms subside, with persistent IgG titers against the SARS-CoV-2 spike, RBD, nucleocapsid and N-terminal domain antigens. Binding and neutralization assays remained highly inhibitory throughout this period. The same was true of antibodies against the other coronaviruses tested as well, an effect that has been seen with other viruses and could be the result of cross-reactive anti-SARS-CoV-2 antibodies. Alternatively, it could be due to the activation of memory B cells formed in response to infection by the seasonal beta-coronaviruses.

Conclusion

IgG titers, particularly against S and RBD, and RBD-ACE2 binding inhibition better differentiate between COVID-19 convalescent and naive individuals than the neutralizing assay,” the researchers concluded.

These could be combined into a single diagnostic test, they suggest, with extreme sensitivity and specificity. The correlation with neutralizing antibody titers could indicate that the neutralizing assay, which is more expensive, sophisticated and expensive, as well as more dangerous for the investigators, could be replaced by the other antibody tests without loss of value.

In short, the study shows that specific antibodies persist for three months at least following recovery; antibody titers correlate with COVID-19-related fever, loss of appetite, abdominal pain and diarrhea; and are also higher in older males with more severe disease, a higher BMI and CCI above 2. Further research would help understand the lowest protective titer that prevents reinfection, and the duration of immunity.

*Important Notice

medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.Journal reference:

Clinical determinants of the severity of COVID-19: A systematic review and meta-analysis

PLOS

Abstract

Objective


We aimed to systematically identify the possible risk factors responsible for severe cases.


Methods

We searched PubMed, Embase, Web of science and Cochrane Library for epidemiological studies of confirmed COVID-19, which include information about clinical characteristics and severity of patients’ disease. We analyzed the potential associations between clinical characteristics and severe cases.


Results

We identified a total of 41 eligible studies including 21060 patients with COVID-19. Severe cases were potentially associated with advanced age (Standard Mean Difference (SMD) = 1.73, 95% CI: 1.34–2.12), male gender (Odds Ratio (OR) = 1.51, 95% CI:1.33–1.71), obesity (OR = 1.89, 95% CI: 1.44–2.46), history of smoking (OR = 1.40, 95% CI:1.06–1.85), hypertension (OR = 2.42, 95% CI: 2.03–2.88), diabetes (OR = 2.40, 95% CI: 1.98–2.91), coronary heart disease (OR: 2.87, 95% CI: 2.22–3.71), chronic kidney disease (CKD) (OR = 2.97, 95% CI: 1.63–5.41), cerebrovascular disease (OR = 2.47, 95% CI: 1.54–3.97), chronic obstructive pulmonary disease (COPD) (OR = 2.88, 95% CI: 1.89–4.38), malignancy (OR = 2.60, 95% CI: 2.00–3.40), and chronic liver disease (OR = 1.51, 95% CI: 1.06–2.17). Acute respiratory distress syndrome (ARDS) (OR = 39.59, 95% CI: 19.99–78.41), shock (OR = 21.50, 95% CI: 10.49–44.06) and acute kidney injury (AKI) (OR = 8.84, 95% CI: 4.34–18.00) were most likely to prevent recovery. In summary, patients with severe conditions had a higher rate of comorbidities and complications than patients with non-severe conditions.

Conclusion

Patients who were male, with advanced age, obesity, a history of smoking, hypertension, diabetes, malignancy, coronary heart disease, hypertension, chronic liver disease, COPD, or CKD are more likely to develop severe COVID-19 symptoms. ARDS, shock and AKI were thought to be the main hinderances to recovery.

For More Information: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0250602

Neurologic Manifestations Associations of COVID-19

High-quality epidemiologic data is still urgently needed to better understand neurologic effects of COVID-19.

Authors: Shraddha Mainali, MD; and Marin Darsie, MD VIEW/PRINT PDF

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection continues to prevail as a deadly pandemic and unparalleled global crisis. More than 74 million people have been infected globally, and over 1.6 million have died as of mid-December 2020. The virus transmits mainly through close contacts and respiratory droplets.1 Although the mean incubation period is 3 to 9 days (range, 0-24 days), transmission may occur prior to symptom onset, and about 18% of cases remain asymptomatic.2 The highest rates of coronavirus disease 2019 (COVID-19) in the US have been reported in adults age 18 to 29 and 50 to 64 years, representing 23.8% and 20.5% of cases, respectively.3 Although adults age 65 and older make up only 14.6% of total cases in the US, they account for the vast majority of deaths (79.9%).3 Similarly, men appear to be more vulnerable to the disease, accounting for 69% of intensive care unit (ICU) admissions and 58% of deaths despite nearly equal disease prevalence between men and women.4 In terms of ethnicity, Black Americans account for 15.6% of COVID-19 infections and 19.7% of related deaths, whereas Hispanic/Latinx Americans account for 26.3% of COVID-19 infections and 15.7% of COVID-19 deaths, despite these groups comprising 13.4% and 16.7% of the US population, respectively.3,5

The most commonly reported symptoms are fever, dry cough, fatigue, dyspnea, and anorexia.2 Numerous studies have also reported a spectrum of neurologic dysfunctions, including mild symptoms (eg, headache, anosmia, and dysgeusia) to severe complications (eg, stroke and encephalitis). Despite the prolific reports of neurologic associations and complications of COVID-19 in the face of a raging pandemic with limited resources, there is a significant lack of control for important confounders including the severity of systemic disease, exacerbation or recrudescence of preexisting neurologic disease, iatrogenic complications, and hospital-acquired conditions. Moreover, given the ubiquity of the virus, it is challenging to parse COVID-19–related complications from coexisting conditions. There is an urgent need for high-quality epidemiologic data reflecting COVID-19 prevalence by age, sex, race, and ethnicity on a local, state, national, and international level.

Neurologic and Neuropsychiatric Manifestations of COVID-19

Prevalence estimates of acute neurologic dysfunctions caused by COVID-19 are widely variable, with reports ranging from 3.5% to 36.4%.6 A recent study from Chicago showed that in those with COVID-19 who develop neurologic complications, 42% had neurologic complaints at disease onset, 63% had them during hospitalization, and 82% experienced them during the course of illness.7 Considering the widespread nature of the pandemic, with millions infected globally, neurologic complications of COVID-19 could lead to a significant increase in morbidity, mortality, and economic burden.

People over age 50 with comorbidities (eg, hypertension, diabetes, and cardiovascular disease) are prone to neurologic complications.2,8 Common nonspecific symptoms include headache, fatigue, malaise, myalgia, nausea, vomiting, confusion, anorexia, and dizziness. COVID-19 is known characteristically to affect taste (dysgeusia) and smell (anosmia) in the absence of coryza with variable prevalence estimates ranging from 5% to 85%.9 Since the first report on hospitalized individuals in Wuhan, China, numerous other reports have indicated a spectrum of mild-to-severe neurologic complications, including cerebrovascular events, seizures, demyelinating disease, and encephalitis.8,10-13 As a result of fragmented data from across the world with diverse neurologic manifestations and multiple potential mechanisms of injury, the classification of neurologic dysfunctions in COVID-19 is complex and varies across the literature. Here we present 2 pragmatic classification approaches based on 1) type and site of neurologic manifestations disease categories.

For More Information: https://practicalneurology.com/articles/2021-jan/neurologic-manifestations-associations-of-covid-19

Lack of antibodies against seasonal coronavirus OC43 nucleocapsid protein identifies patients at risk of critical COVID-19

Authors: MartinDugasa1TanjaGrote-Westrickb1UtaMerledMichaelaFontenaylmAndreas E.KremerhFrankHansesijRichardVollenbergcEvaLorentzenbShilpaTiwari-BecklerdJérômeDucheminlSyrineEllouzelMarcelVetterhJuliaFürsthPhilippSchusterkTobiasBrixaClaudia M.DenkingerfgCarstenMüller-TidoweHartmutSchmidtcJoachimKühnb1

Highlights

Does prior infection with seasonal human coronavirus OC43 protect against critical COVID-19?•

Findings: In an international multi-center study inpatients without anti-HCoV OC43 NP antibodies had an increased risk of critical disease.•

Meaning: Prior infections with seasonal HCoV OC43 have a protective effect against critical COVID-19.

Abstract

Background

The vast majority of COVID-19 patients experience a mild disease. However, a minority suffers from critical disease with substantial morbidity and mortality.

Objectives

To identify individuals at risk of critical COVID-19, the relevance of a seroreactivity against seasonal human coronaviruses was analyzed.

Methods

We conducted a multi-center non-interventional study comprising 296 patients with confirmed SARS-CoV-2 infections from four tertiary care referral centers in Germany and France. The ICU group comprised more males, whereas the outpatient group contained a higher percentage of females. For each patient, the serum or plasma sample obtained closest after symptom onset was examined by immunoblot regarding IgG antibodies against the nucleocapsid protein (NP) of HCoV 229E, NL63, OC43 and HKU1.

Results

Median age was 60 years (range 18-96). Patients with critical disease (n=106) had significantly lower levels of anti-HCoV OC43 nucleocapsid protein (NP)-specific antibodies compared to other COVID-19 inpatients (p=0.007). In multivariate analysis (adjusted for age, sex and BMI), OC43 negative inpatients had an increased risk of critical disease (adjusted odds ratio (AOR) 2.68 [95% CI 1.09 – 7.05]), higher than the risk by increased age or BMI, and lower than the risk by male sex. A risk stratification based on sex and OC43 serostatus was derived from this analysis.

Conclusions

Our results suggest that prior infections with seasonal human coronaviruses can protect against a severe course of COVID-19. Therefore, anti-OC43 antibodies should be measured for COVID-19 inpatients and considered as part of the risk assessment for each patient. Hence, we expect individuals tested negative for anti-OC43 antibodies to particularly benefit from vaccination against SARS-CoV-2, especially with other risk factors prevailing.

For More Information: https://www.sciencedirect.com/science/article/pii/S1386653221001141

Lack of antibodies against seasonal coronavirus OC43 nucleocapsid protein identifies patients at risk of critical COVID-19

Authors: Martin Dugas 1Tanja Grote-Westrick 2Uta Merle 3Michaela Fontenay 4Andreas E Kremer 5Frank Hanses 6Richard Vollenberg 7Eva Lorentzen 8Shilpa Tiwari-Heckler 9Jérôme Duchemin 10Syrine Ellouze 11Marcel Vetter 12Julia Fürst 13Philipp Schuster 14Tobias Brix 15Claudia M Denkinger 16Carsten Müller-Tidow 17Hartmut Schmidt 18Phil-Robin Tepasse 19Joachim Kühn 20

Abstract

Background: The vast majority of COVID-19 patients experience a mild disease. However, a minority suffers from critical disease with substantial morbidity and mortality.

Objectives: To identify individuals at risk of critical COVID-19, the relevance of a seroreactivity against seasonal human coronaviruses was analyzed.

Methods: We conducted a multi-center non-interventional study comprising 296 patients with confirmed SARS-CoV-2 infections from four tertiary care referral centers in Germany and France. The ICU group comprised more males, whereas the outpatient group contained a higher percentage of females. For each patient, the serum or plasma sample obtained closest after symptom onset was examined by immunoblot regarding IgG antibodies against the nucleocapsid protein (NP) of HCoV 229E, NL63, OC43 and HKU1.

Results: Median age was 60 years (range 18-96). Patients with critical disease (n=106) had significantly lower levels of anti-HCoV OC43 nucleocapsid protein (NP)-specific antibodies compared to other COVID-19 inpatients (p=0.007). In multivariate analysis (adjusted for age, sex and BMI), OC43 negative inpatients had an increased risk of critical disease (adjusted odds ratio (AOR) 2.68 [95% CI 1.09 – 7.05]), higher than the risk by increased age or BMI, and lower than the risk by male sex. A risk stratification based on sex and OC43 serostatus was derived from this analysis.

Conclusions: Our results suggest that prior infections with seasonal human coronaviruses can protect against a severe course of COVID-19. Therefore, anti-OC43 antibodies should be measured for COVID-19 inpatients and considered as part of the risk assessment for each patient. Hence, we expect individuals tested negative for anti-OC43 antibodies to particularly benefit from vaccination against SARS-CoV-2, especially with other risk factors prevailing.

For More Information: https://pubmed.ncbi.nlm.nih.gov/33965698/

Attributes and predictors of long COVID

  1. Authors: Carole H. SudreBenjamin MurrayClaire J. Steves

Abstract

Reports of long-lasting coronavirus disease 2019 (COVID-19) symptoms, the so-called ‘long COVID’, are rising but little is known about prevalence, risk factors or whether it is possible to predict a protracted course early in the disease. We analyzed data from 4,182 incident cases of COVID-19 in which individuals self-reported their symptoms prospectively in the COVID Symptom Study app1. A total of 558 (13.3%) participants reported symptoms lasting ≥28 days, 189 (4.5%) for ≥8 weeks and 95 (2.3%) for ≥12 weeks. Long COVID was characterized by symptoms of fatigue, headache, dyspnea and anosmia and was more likely with increasing age and body mass index and female sex. Experiencing more than five symptoms during the first week of illness was associated with long COVID (odds ratio = 3.53 (2.76–4.50)). A simple model to distinguish between short COVID and long COVID at 7 days (total sample size, n = 2,149) showed an area under the curve of the receiver operating characteristic curve of 76%, with replication in an independent sample of 2,472 individuals who were positive for severe acute respiratory syndrome coronavirus 2. This model could be used to identify individuals at risk of long COVID for trials of prevention or treatment and to plan education and rehabilitation services.

Main

COVID-19 can manifest a wide severity spectrum from asymptomatic to fatal forms2. A further source of heterogeneity is symptom duration. Hospitalized patients are well recognized to have lasting dyspnea and fatigue in particular3, yet such individuals constitute only a small proportion of symptomatic COVID-19 (ref. 4). Few studies capture symptoms prospectively in the general population to ascertain with accuracy the duration of illness and the prevalence of long-lasting symptoms.

Here, we report a prospective observational cohort study of COVID-19 symptoms in 4,182 users of the COVID Symptom Study who reported testing positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and started logging on the app when feeling physically normal, enabling accurate determination of symptom onset (Methods)5,6. Symptom duration in these individuals was compared with that in age-, sex- and body mass index (BMI)-matched symptomatic controls who tested negative for COVID-19.

We then compared users with symptoms persisting over 28 d (LC28) to users with shorter duration of symptoms, that is, less than 10 d (short COVID). Our previous findings that clusters of symptoms predicted the need for acute respiratory support7 led us to hypothesize that persistent symptomatology in COVID-19 (long COVID) is associated with early symptom patterns that could be used for prediction.

For More Information: https://www.nature.com/articles/s41591-021-01292-y

Severe covid-19 pneumonia: pathogenesis and clinical management

Authors: Amy H Attaway, assistant professor of medicine, associate director, COPD center1,  Rachel G Scheraga, assistant professor of medicine2,  Adarsh Bhimraj, head, section of neurological infections; staff, infectious diseases1,  Michelle Biehl, associate staff, pulmonary and critical care medicine; director, post ICU recovery clinic1,  Umur Hatipoğlu, associate professor of medicine; director, respiratory therapy; director, COPD center1

Abstract

Severe covid-19 pneumonia has posed critical challenges for the research and medical communities. Older age, male sex, and comorbidities increase the risk for severe disease. For people hospitalized with covid-19, 15-30% will go on to develop covid-19 associated acute respiratory distress syndrome (CARDS). Autopsy studies of patients who died of severe SARS CoV-2 infection reveal presence of diffuse alveolar damage consistent with ARDS but with a higher thrombus burden in pulmonary capillaries. When used appropriately, high flow nasal cannula (HFNC) may allow CARDS patients to avoid intubation, and does not increase risk for disease transmission. During invasive mechanical ventilation, low tidal volume ventilation and positive end expiratory pressure (PEEP) titration to optimize oxygenation are recommended. Dexamethasone treatment improves mortality for the treatment of severe and critical covid-19, while remdesivir may have modest benefit in time to recovery in patients with severe disease but shows no statistically significant benefit in mortality or other clinical outcomes. Covid-19 survivors, especially patients with ARDS, are at high risk for long term physical and mental impairments, and an interdisciplinary approach is essential for critical illness recovery.

Introduction

The ongoing outbreak of the coronavirus disease 2019 (covid-19) has posed immense challenges for the research and medical communities. This review focuses on the epidemiologic and clinical features of covid-19, the pathophysiologic mechanisms, inpatient respiratory support, and the evidence to date on drug treatments. It also covers the recovery and long term management of patients with covid-19 pneumonia. The review is aimed at clinicians and intensivists caring for patients with severe covid-19 pneumonia as defined by the National Institutes of Health,1 referring to individuals with SARS-CoV-2 infection confirmed by polymerase chain reaction (PCR) testing who have SpO2 <94% on room air at sea level, a ratio of arterial partial pressure of oxygen to fraction of inspired oxygen (PaO2/FiO2) <300 mm Hg, respiratory frequency >30 breaths/min, or lung infiltrates >50%.

For More Information: https://www.bmj.com/content/372/bmj.n436