Monday, July 13, 2020

152 CMAAO CORONA FACTS and MYTH BUSTER Covid in Children, Neurology

152 CMAAO CORONA FACTS and MYTH BUSTER Covid in Children, Neurology

Dr K Aggarwal
President CMAAO
With inputs from Dr Monica Vasudev
9743: Minutes of Virtual Meeting of CMAAO NMAs on “Covid in children & Covid and neurology”

11th July, 2020, Saturday, 9.30am-10.30am

Participants, Member NMAs

Dr KK Aggarwal, President CMAAO
Dr Yeh Woei Chong, Singapore Chair CMAAO
Prof Ashraf Nizami, Pakistan First Vice President CMAAO
Dr N Gnanabaskaran, President Malaysian Medical Association
Dr Marthanda Pillai, Member World Medical Council
Dr Alvin Yee-Shing Chan, Hong Kong, Treasurer CMAAO
Dr Koh Kar Chai, Malaysia Co Chair CMAAO
Dr Marie Uzawa Urabe, Japan Medical Association
Dr Qaisar Sajjad, Pakistan Medical Association, Secretary
Dr Prakash Budhathoky, Nepal Medical Association


Dr Russell D’Souza, UNESCO Chair in Bioethics, Australia
Dr Sanchita Sharma, Editor IJCP Group

Prof Ashraf Nizami and Dr Alvin Yee-Shing Chan spoke on Covid in children and Covid and neurology, respectively. Here are key points from each presentation.

Covid-19 in children and Pakistan

Prof Ashraf Nizami
First Vice President CMAAO
Immediate Past President PMA Center
President PMA Lahore

In his presentation, Prof Ashraf Nizami spoke on Covid-19 in children and also highlighted the role of government and particularly the Pakistan Medical Association (PMA) in dealing with Covid-19 in Pakistan. The first case was reported in Pakistan on 6th February.

  • There was a general perception that children are not affected by this pandemic. But the fact is that all children of all ages in all countries are affected. This is a universal crisis and will have lifelong impact for some children as it is not just a health issue. It is also social and psychological issue.

  • Clinical symptoms in children include abdominal pain, diarrhea and vomiting, red rash, cracked lips, red eyes, high fever, swollen glands on neck and swollen hands and feet.

  • As per data on July 1, about 7.28% of the total reported cases in Pakistan are in people below 19 years of age. The mortality is 0.46% (16 out of 3501 under 15 years). Three suspected cases of Kawasaki disease have been reported in Lahore; also from Karachi, Rawalpindi and Islamabad.

  • Covid has an impact on social growth. About 30% of industry is affected. Education is disturbed and only about 30% of children in Pakistan have access to technology in education (online). Healthcare services have been affected. Covid has also affected the physical and mental growth of children.

  • The pandemic has led to anxiety and depression not only in children but also the parents. Incidence of domestic violence against women has increased due to lockdown, which has an impact on children and the family. Exploitation and child abuse have happened.

  • Covid-19 has compromised access to health services due to lockdown; the basic health services are delayed due to SOPs in place. Polio vaccination has been affected; besides Pakistan and Afghanistan, recent outbreaks have been reported in Africa, East Asia and the Pacific.

  • The government is creating awareness about the disease; special institution have been designated for children. Special counters have been created in hospitals.

  • According to UNICEF, adequate water, sanitation and hygiene services for households, schools and healthcare facilities are essential to prevent spread of infectious diseases including Covid-19; 3 billion homes do not have soap and water; 900 million children do not have soap and water at schools.

  • PMA is an active participant in Covid-19 activities. It was the first organization in Pakistan which spoke about Covid-19 and created awareness and raised an alarm about the outbreak. It also looks after coordination among doctors, government, social activities and people. A scientific meeting was organized for family physicians, who are considered as front liners. PMA is also developing guidelines with information derived from WHO, CMAAO, London School of Economics etc.

  • PMA is working on telemedicine facilities, analysis of government policies, plans and actions. It is playing an active role in advocacy and implementation of WHO recommendations as per local needs as well as international experiences.

  • PMA is pressing upon the government that curative services should not be compromised, to start immunization services with all SOPs; it is critical of the government’s decision to reopen schools. Psychology and psychiatric teleconsultations are being planned.

Covid and Neurology

Dr Alvin Yee-Shing Chan
Treasurer CMAAO
Vice Chairman, HKMA Charitable Foundation

  • About 36.4 % of Covid patients from Wuhan China had neurological involvement; manifestations were more in cases of severe infection.

  • Acute cerebrovascular diseases occurred in 5.7% of those severe cases vs 0.08% of milder cases.

  • 14% of severe cases had impaired consciousness vs 2.4% of mild cases.

  • Musculoskeletal injury occurred in 19.3% of severe cases vs 4.8% of mild cases.

  • Neurological signs and symptoms are much higher in patients in intensive care: mental confusion and agitation (69%), diffuse corticospinal tract signs with enhanced tendon reflexes, ankle clonus, bilateral extensor plantar reflexes (67%).

  • 33% of discharged patients (33%) had dysexecutive syndrome consisting of inattention, disorientation, or poorly organized movements in response to command

  • MRI brain, in most of the patients, will show leptomeningeal enhancement, bilateral frontotemporal hypoperfusion, ischemic stroke; encephalopathic pattern on EEG.

  • Clinically, these patients may have milder symptoms (hyperosmia, anosmia, headache, weakness, altered consciousness); patients with more severe infection have encephalitis with demyelination, neuropathy, and stroke.

  • Invasion of the medullary cardiorespiratory center by the SARS CoV-2 virus may cause refractory respiratory failure in ICU patients.

  • The route of entry is mostly through olfactory bulbs – olfactory tracts in the brain.

  • Human coronaviruses have neuroinvasive capability. Misdirected host immune responses can damage the CNS, which is associated with autoimmunity in the susceptible persons, resulting in virus induced neuro-immunopathology. The virus replication directly damages the CNS.  ACE2 receptors occur in olfactory epithelium 70 times more than in tracheal or nasal epithelium. This is why anosmia occurs so frequently in this disease.

  • The ACE2 receptor expression differs in neurons and glial cells and so immunopathology differs in different persons.

  • Since ACE2 receptors are present in brain cells, the BBB presents no problem to the new corona virus. The virus has been detected in brain samples on autopsies and offers an explanation about the neurological sequelae even when the patients survive.

  • Possible mechanism of direct neuronal damage: The trans-neuronal retrograde machinery is a possible route of neuronal invasion. The virus first infects peripheral neurons to invade the CNS via the axonal retrograde transport. It infects another neuron via synapses. The virus is released by exocytosis in the presynaptic terminal. It then binds to ACE2 receptor on the postsynaptic neuron. It gains entry into the neuroplasm via the receptor-mediated endocytosis. It causes cell death via apoptosis.

  • Covid-19 induces anti-cardiolipin antibodies endothelialitis thrombosis (venous and arterial) stroke, cerebrovascular accidents.

  • The direct attack on neurons will cause milder cases, but if there is massive invasion of key neuronal cells, this may cause dysexecutive function. The vasculitis and endothelitis is instrumental in severe cases stroke, and cell death due to ischemia.

  • Hong Kong has very few pediatric patients and they have mild infection. There is resurgence in community spread with more than 40 cases with no obvious source. 7500 tests in a day, which is inadequate. No medical health staff has been infected through hospital or clinic. The silent cases in community are a cause of concern.

Acute presentation

Dr KK Aggarwal
President CMAAO

Look for the following points in every patient who presents with onset of illness less than
3 months. Classifying patients accordingly makes it easier to manage them.

  • Is the clinical presentation of Covid is due to inflammation? There will be signs of inflammation like IL-6, ESR, CRP, ferritin Give anti-inflammatory drugs; steroids are the most potent anti-inflammatory drugs
  • Can this be because of hypercoagulable state? e.g. thrombotic stroke/MI/appendicitis/gangrene/happy hypoxia (microclot formation in lung vessels): Do d-dimer; high d-dimers mean hypercoagulable state  
  • Is there any immunological reaction (immediate or delayed) - humoral? Vasculitis, look for rash, CRP is normal, high platelets;
  • Is there cellular immunological response? Cytokine crisis
  • Except for hypercoagulable state, all will respond to steroids. So, combination of LMWH and steroids is standard treatment.
  • Some patients may have simple viral response and illness will resolve spontaneously in 2-3 days; some will show a bacterial response with slightly high polymorphs – typhoid test may be falsely positive in such patients; some patients may have low CD4 count indicating HIV-like activity.


Sunday, July 12, 2020



Dr K Aggarwal
President CMAAO
With inputs from Dr Monica Vasudev

973: IMA-CMAAO Webinar on “Covid testing” 11th June, 2020 4-5pm

Dr KK Aggarwal, President CMAAO
Dr RV Asokan, Hony Secretary General IMA
Dr Ramesh K Datta, Hony Finance Secretary IMA
Dr Jayakrishnan Alapet
Dr Brijendra Prakash
Dr Girdhari Kanuga
Dr Sanchita Sharma


Dr Shalabh Malik
National Head Microbiology
Dr Lal Path Labs

Key points from the discussion

  • The coronavirus is a new virus and with no proven therapy or a vaccine as of date, diagnostic testing becomes an important tool for management of patient with Covid-19.

  • Lab test options available: Molecular, antigen (point of care test, CARD test) and antibody (rapid – not allowed in India so far, CLIA – automated platform, ELISA, IgG/IgM, total (combination of IgG and IgM)

  • Molecular: Conventional (results within 6-8 hours), Automated, which is a closed system – CB-NAAT (gives result in 45 minutes), TruNat (within 2 hours; it first screens for envelope (E) gene, which is common to all coronaviruses and then RdRP [RNA-dependent RNA polymerase] gene, which is specific for Covid-19).

  • The purpose of testing is diagnostic, sero-surveillance, or to know exposure (as around 40-45% of cases are asymptomatic) or immunity levels.

  • Covid testing in India is very regulated, as per ICMR and government guidelines. RT PCR is gold standard investigation; recently Antigen test has been allowed.

  • As per ICMR revised guidelines, patients to be selected for testing include symptomatic international traveler in last 14 days, symptomatic contact of lab confirmed case, symptomatic healthcare worker, hospitalized SARI patient, asymptomatic direct and high risk contact of lab-confirmed cases, asymptomatic healthcare worker in contact with confirmed case without adequate precaution and symptomatic ILI patient in hospital/clusters as identified by the Health ministry.

  • Pre-requisites before testing: As it is a pandemic, every result has to be notified. Doctor’s prescription + Covid-19 ICMR form (patient details, history, clinical features, Govt. ID) is mandatory requirement; infrastructure (BSL-3 or at least BSL-2 facility), trained personnel, waste disposal, judicious training and use of PPE are other testing pre-requisites.

  • Specimen type: nasopharyngeal/oropharyngeal swab; nasopharyngeal has better sensitivity – proper sample collection is crucial. Nylon swabs are used as coronavirus stays longer on synthetic material. Then immediately transfer to VTM (viral transport medium); shipped at 2-8oC with appropriate 3-layer packing. In later stages of infection, bronchoalveolar lavage or endotracheal aspirate is better. Recent studies have shown saliva to be better than nasopharyngeal or oropharyngeal swab.

  • RT PCR: Minimum two gene targets (E gene and RdRP gene) need to be pinpointed to declare as RT PCR positive. More the number of targets better is the sensitivity.

  • If E gene, Rd RP gene and RP gene are positive, this confirms detection of SARS-CoV-2. If one gene is positive and the other is negative, the test is inconclusive; repeat the test or take a fresh sample. If E gene and Rd Rp gene are negative and R P gene is positive, the test is negative for SARS CoV-2 virus.

  • It is a qualitative test as it does not give quantitative assay of viral load. Ct (cycle threshold) can give a clue about the severity of infection. If Ct value is low, this indicates high viral load. If high Ct value, this indicates low viral load. Every lab should report Ct value.

  • All reporting (negative/positive) is done on ICMR website and is highly confidential.

  • Advantages of RT PCR: Speed and sensitivity, early detection and isolation, identification of infected persons which helps in management and implementation of mitigation strategies in containment areas

  • Disadvantages of RT PCR: BSL3 or 2 level facilities are required, PPE training, skilled personnel, false negative test (sampling error, very early disease, incorrect transportation)

  • Rapid antigen test: ICMR recommended (14.6.20), sample collection to reading the result should be done within one hour, prescription/Form 44 are mandatory. If antigen test is negative, but person has symptoms suggestive of Covid-19, then RT PCR is mandatory. Sensitivity is around 50-53%. Specificity is good.

  • Antibody tests: Not used for diagnosis, only for seroprevalence studies; community screening of asymptomatic infections, contact tracing, evaluate results of vaccine trials, immunity. Notification is a must; prescription and form are not mandatory.

  • IgM appears first and then IgG. IgM appears around Day 4, rises to peak around Day 14 and disappears by Day 28. IgG appears around Day 8/9, rises to peak around Day 21 and then stays on. The longevity of IgG is not known. So retesting is done after 3 months.

  • Three types of seroconversion are seen in Covid-19: IgG and IgM may appear at the same time (synchronous seroconversion), IgM seroconversion earlier than IgG, IgM seroconversion later than IgG.

  • There is no advisory yet on IgM testing.

  • Total antibody (IgG + IgM) positive: Exposure to SARS CoV-2 is confirmed and antibodies have developed. If symptomatic, refer to RTPCR; if asymptomatic, then quarantine and repeat IgG x7-10 days.

  • Total antibody (IgG + IgM) negative: Exposure not confirmed, antibodies not developed. If person is symptomatic, do RT PCR; if asymptomatic, then this confirms negative result.

  • Surgical or medical intervention emergency: If antigen negative, antibody positive – is symptomatic, then do PCR; if asymptomatic, then go ahead with surgery.

  • Back to work: If IgG positive, join work (retest after 3 months), if IgG negative and symptomatic, do RT PCR (If positive, quarantine; if negative retest IgG after 14 days), if IgG negative and asymptomatic, join work.

  • Cross reactivity with other viruses like dengue or bacteria like typhoid is being seen.

  • Best test when deciding plasma donor is neutralization test. This requires BSL3+ facility.

  • If PCR positive, antigen negative: low viral load. For antigen test to be positive, high viral load is required. PCR is sensitive for low viral load.

Summary of testing for Covid 19

Ideal time to test from onset of illness
0-14 days
Confirmatory test
High sensitivity
Best for testing symptomatic persons
High cost of infrastructure

Complex sample collection and handling

High TAT 2.5-3 hours for testing 1 patient

Rapid Antigen
0-14 days
Acute and early infection
Faster result
Cost effective
Can be used for mass screening
Relatively low sensitivity vs RT PCR

Complex sample collection and handling

4-21 days
Community screening for detecting active and early infections

Shorter turnaround time
Easy sample collection and transport
Cost effective
High throughput analyzers present across the country
Limited evidence on clinical efficacy of serology based Antibody tests

Can’t be used for detecting early infections esp 0-4 days
≥ 7 days
Assess immunity
Screen potential plasma donors
Assess recovery and past exposure to the virus, return to work

Saturday, July 11, 2020



Dr K Aggarwal
President CMAAO
With inputs from Dr Monica Vasudev

971:  New WHO Guidance Calls for More Evidence on Airborne Transmission

1.    The WHO on Thursday released new guidelines on the transmission of the novel coronavirus that acknowledge some reports of airborne transmission of the virus that causes COVID-19, ut stopped short of confirming that the virus spreads through the air.
2.    WHO acknowledged that some outbreak reports related to indoor crowded spaces have suggested the possibility of aerosol transmission, such as during choir practice, in restaurants or in fitness classes. (
3.    WHO said the coronavirus that causes COVID-19 spreads through contact with contaminated surfaces or close contact with infected people who spread the virus through saliva, respiratory secretions or droplets released when an infected person coughs, sneezes, speaks or sings.
4.    People should avoid crowds and ensure good ventilation in buildings, in addition to social distancing, and encourage masks when physical distancing is not possible.
5.    Pandemic is driven by super-spreading events, and that the best explanation for many of those events is aerosol transmission
6.     People without symptoms - to wear masks.
7.    Only a very small number of diseases are believed to be spread via aerosols, or tiny floating particles. These include measles and tuberculosis - two highly contagious pathogens that can linger in the air for hours and require extreme precautions to prevent exposure.
8.     WHO is using an "outdated definition of droplets and aerosols" and is too focused on the size of the droplets and the distance they travel. WHO defines aerosols as being under 5 microns because only particles that small could float in the air long enough to be inhaled. However, Linsey Marr, an aerosol expert at Virginia Tech  said a much larger range of particle size has been shown to contribute to infection. Rather than size, the differences between droplets and aerosols should be based on how the infection occurs: If a person inhales the virus and becomes infected, it's an aerosol. If the infection occurs by contact, they are droplets. Although WHO has been focused on airborne transmission at long distances, Marr said breathing in aerosols "is of greater concern at close contact and when people are in the same room. [Reuters]

972: Predictors of survival in COVID-19 patients treated with tocilizumab

1.     Receipt of the IL-6 receptor antagonist tocilizumab within 12 days of symptom onset in patients with severe coronavirus disease 2019 (COVID-19) was an independent predictor for in-hospital survival at 28 days, according to a study published in the Journal of Autoimmunity.
2.      Patients were eligible for tocilizumab if they exhibited persistent fevers (38.0 °C for greater than 6 hours), had PaO2/FiOof < 200, and exhibited persistently rising inflammatory laboratory parameters (ferritin, D-dimer, and lactate dehydrogenase [LDH]) or an elevated inflammatory laboratory parameter defined as ferritin ≥1000 μg/L, D-dimer ≥ 5 mg/mL, or LDH ≥ 500 U/L. An IL-6 level ≥ five times the upper limits of normal (≤5 pg/ml) was assessed in addition to these parameters.
3.      Tocilizumab was administered as an 8 mg/kg IV dose using actual body weight with a maximum dose of 800 mg. Patients were eligible for a second dose if persistently febrile despite treatment. Due to medication shortages the tocilizumab dose was changed to a fixed 400 mg IV dose for all patients on March 30, 2020. All patients were followed for up to 28 days from the first dose.
4.      Results showed that the 28-day in-hospital mortality was 43.2%, leaving 46 patients in the survivors and 35 in the non-survivors group. According to the authors, the single independent predictor of 28-day in-hospital survival was receipt of tocilizumab within 12 days of symptom onset (adjusted OR: 0.296, 95% CI: 0.098–0.889). Meanwhile, a SOFA score ≥8 was independently associated with 28-day in-hospital mortality (adjusted OR: 2.842, 95% CI: 1.042–7.753).
5.      Patients in the survivor group were more likely to have a clinical response to tocilizumab by day 28 (80.4% vs 5.7%; p < 0.001). Improvements in the six-point ordinal scale and SOFA score were observed in survivors after tocilizumab. Further, the hospital length of stay was longer in the survivor group compared to non-survivors (27.5 days [14–31] vs 14 days [9–20]; p < 0.001), while 14 (17.3%) patients remained hospitalized at the end of the study.

Friday, July 10, 2020

149 CMAAO CORONA FACTS and MYTH BUSTER Best time to donate plasma is 28 to 40 days

149 CMAAO CORONA FACTS and MYTH BUSTER Best time to donate plasma is 28 to 40 days

Dr K Aggarwal
President CMAAO

971:   COVID-19 Plasma Donors HAVE Higher Levels of IgG 28 DAYS After Symptom Onset

IgG in COVID-19 convalescent plasma donors appears to reach higher levels four weeks following onset of symptoms, suggesting that's the optimal time to collect plasma. In a study of 49 convalescent plasma donors, researchers found that plasma levels were lower when the donation occurred less than 28 days from the onset of symptoms compared to levels in patients who donated after four weeks, according to the results published in Transfusion.

Having had a fever lasting three or more days or a body temperature that exceeded 101.3 degrees F was also associated with increased IgG levels in the recovered patients.

Among the 49 convalescent plasma donors, 90% had a titer of >1:160 and 78% had a titer of ≥ 1:640.

Based on the selection criterion of donating plasma four weeks after the onset of symptoms, there were 42 convalescent plasma donors, of whom 90% had a titer of 1: 160 and 84% had a titer of ≥ 1:640. There was no correlation between S-RBD-specific IgG antibody and age, gender or donor blood type.

To take a closer look at donor characteristics, Dr. Li and colleagues recruited patients who had recovered from COVID-19, were aged 18 to 55 years, were eligible for blood donation, had two negative COVID-19 nasopharyngeal swab tests on PCR at least 24 hours apart, had been discharged from the hospital for more than two weeks and had no COVID-19 symptoms prior to donation.

IgG was measured with an ELISA assay that was developed in-house, and the researchers also confirmed the antibodies' neutralized SARS-CoV-2 in cell culture after five days.

One reassuring thing in the patients at Mount Sinai is that people over 65 also had high titers.

Thursday, July 9, 2020



Dr K Aggarwal
President CMAAO

970:   WHO confirms there's 'emerging evidence' of airborne transmission of coronavirus?

(CNN)The WHO confirmed there is "emerging evidence" of airborne transmission of the coronavirus following the publication of a letter Monday signed by 239 scientists that urged the agency to be more forthcoming about the likelihood that people can catch the virus from droplets floating in the air. Dr. Benedetta Alleganzi, WHO Technical Lead for Infection Prevention and Control, said "We acknowledge that there is emerging evidence in this field, as in all other fields regarding the Covid-19 virus and pandemic and therefore we believe that we have to be open to this evidence and understand its implications regarding the modes of transmission and also regarding the precautions that need to be taken.
Many of the letter's signatories are engineers, "which adds to growing knowledge about the importance of ventilation. We have been talking about the possibility of airborne transmission and aerosol transmission as one of the modes of transmission of Covid-19, as well as droplet. WHO has looked at fomites, fecal oral, mother to child, animal to human as well. 
The possibility of airborne transmission in public settings, especially in specific conditions crowded, closed, poorly ventilated settings that have been described cannot be ruled out. Airborne droplet nuclei are particles of respiratory secretions <5 microns. Droplet nuclei can remain suspended in the air for extended periods and thus can be a source of inhalational exposure for susceptible individuals.

Good for India if it is air born
1. Focus will change to air born prevention
2. TB is also air born, control measures will also control it
3. Measles and chicken pox ware also air borne and will get prevention focus
4. Airborne infection isolation rooms will become a reality in every emergency room and health cate settings
5. N 95 masks will become a fashion and reality in crowded, poorly ventilated, closed and polluted settings
6. N 95 industry will boom in the country
7. N95 masks will make life easier due to reduction in PM 2.5 related illnesses and will reduce the burden of heart attacks and paralysis
8. Role of air purifier will become more important in indoor settings
9. There will be surge of open ventilation, ventilated houses and hospitals and open restaurants
10. Gatherings will become less crowded

Wednesday, July 8, 2020



Dr K Aggarwal
President CMAAO

968:   Update on Covid-19

IMA-CMAAO Webinar on “Imaging and Covid-19”

4th July, 2020, 4-5pm


Dr KK Aggarwal, President CMAAO
Dr RV Asokan, Hony Secretary General IMA
Dr Ramesh K Datta, Hony Finance Secretary IMA
Dr Jayakrishnan Alapet
Dr Tulsi
Dr Brahm Prakash
Dr VK Venugopal
Dr Rajan
Dr Manish Jha
Dr DS Chadha
Dr Promila Pankaj
Dr VK Goel
Dr LC Jain
Dr Arpita Joshi
Kabir Mahajan
Jacob Ninan
Dr Divakar Rana
Mr HK Gohil
Mr Vijay Khanna
Ravi Bindra
Dr S Sharma


Dr Harsh Mahajan
Chief Radiologist, Mahajan Imaging
Chairman, Centre for Advanced Research in Imaging, Neuroscience and Genomics (CARING)
New Delhi

Key points

·        Chest x-ray (CXR) is typically the first line imaging modality for patients with suspected Covid-19, although less sensitive than chest CT. It may be normal in early or mild disease. Even with serious disease, about 31% had normal CXR at the time of admission. Findings are most extensive about 10-12 days after onset of symptoms.

·        Findings on CXR: most frequent are airspace opacities (described as consolidation or ground glass opacities), which are often bilateral, peripheral and mainly in the lower zone. Pleural effusion is very rare (if patient has pleural effusion, chances are that it may not be Covid).

·        Oblique CXR is done when lesion (subpleural or close to chest cavity) is not seen on routine AP view but there may be some data on CT.

·        Point of care ultrasound: It is useful to monitor disease progression in patients who have hypoxemia and hemodynamic failure. It is not a sensitive and specific modality, but its advantages are inexpensive, ease of use, repeatability and no exposure to radiation. However, there is high risk of exposure to the operator, so used less.

·        Findings on USG: Multiple B-lines, subpleural consolidation, irregular thickened pleural line with scattered discontinuities, alveolar consolidation, reappearance of bilateral A-lines; return of normal A-lines from B-lines suggest that the patient is improving.

·        CT chest: A systematic meta-analysis of 49 studies of CT features of Covid-19 by CARING showed that the commonest finding at all stages of the disease was diffuse bilateral ground glass opacity. The next common findings were consolidations and mixed density lesions. Around 78% of patients with RT-PCR positive had either ground-glass opacities or consolidation or both.

·        There is a significant overlap of CT scan findings between Covid and non-Covid patients, who present as SARI or ILI.

·        Common CT findings: Ground glass opacities, consolidation, mixed lesions, crazy paving pattern, reticulations, septal thickening (can be inter- or intra-lobular; commonly seen in advanced disease)

·        Specific CT findings: Halo sign, reverse Halo sign (focal rounded area of GGO surrounded by a complete ring of consolidation; one of the typical findings of Covid-19 as per RSNA), spider web sign, pulmonary vessel engorgement (prominent pulmonary vessels in relation to the lesions; it is a potential early predictor of lung impairment), vacuolar sign (vacuole-like transparent shadow <5mm in length observed in the lesion)

·        Infrequent CT findings: Architectural distortion, lymph node enlargement and pleural effusion

·        In initial stages, GGOs can be unilateral and patchy progressing to multifocal confluent lesions with advancing disease.

·        If crazy paving pattern and vascular engorgement, the patient needs to be treated more aggressively.

·        Pulmonary embolism is emerging as main pathogenesis in Covid-19, which can lead to pulmonary infarction. A contrast-enhanced CT pulmonary angiography is done when PE is suspected.

·        CT severity score: it scores lung opacities in all 6 lung zones (3 on each side), the sum of scores from all 6 is the overall CT score (maximum score 24). The severity of lung involvement on CT correlates with disease severity.

·        Extra-thoracic Covid manifestations: Covid-19-associated acute hemorrhagic necrotizing encephalopathy, multisystem inflammatory syndrome (airway inflammation and rapid development of pulmonary edema on thoracic imaging, coronary artery aneurysms and extensive right iliac fossa inflammatory changes on abdominal imaging)

·        CT should not be used as initial screening or diagnostic tool. It can be used to identify early markers for lung impairment in symptomatic patient with RTPCR positive for Covid-19 or for patients with non-resolving symptoms to evaluate disease progression.

·        The role of CT in stable pediatric patients is limited.

·        X-ray should not be used as initial screening tool for Covid-19. In suspected patients with history of fever, dry cough, do a RT PCR first instead of chest x-ray.

·        All patients coming to Radiology with any respiratory symptoms should be considered a potential Covid-19 patient. Accordingly, all precautions should be taken. No mixing with other patients, maintain social distancing, sanitize equipment before using it for the next patient.

·        Portable x-rays are used for temporal progression and resolution and also for serial follow-ups. Use a dedicated machine wherever logistically possible.