Soon, a blood test to detect shaken baby syndrome

COVID-19 mostly kills through an overreaction of the immune system, whose function is precisely to fight infections, say scientists who have decoded the mechanisms, symptoms, and diagnosis of the disease caused by the SARS-Cov-2 coronavirus.

In a study published in the journal Frontiers in Public Health, the researchers explained step-by-step how the virus infects the airways, multiplies inside cells, and in severe cases causes the immune defences to overshoot with a "cytokine storm".

This storm is an over-activation of white blood cells, which release too-great amounts of cytokines -- inflammation-stimulating molecules --into the blood, they said.

"Similar to what happens after infection with SARS and MERS, data show that patients with severe COVID-19 may have a cytokine storm syndrome," said study author Daishun Liu, Professor at Zunyi Medical University in China.

"The rapidly increased cytokines attract an excess of immune cells such as lymphocytes and neutrophils, resulting in an infiltration of these cells into lung tissue and thus cause lung injury," Liu said.

The researchers explained that the cytokine storm ultimately causes high fever, excessive leakiness of blood vessels, and blood clotting inside the body.

It also causes extremely low blood pressure, lack of oxygen and excess acidity of the blood, and build-up of fluids in the lungs, they said.

The researchers noted that white blood cells are misdirected to attack and inflame even healthy tissue, leading to failure of the lungs, heart, liver, intestines, kidneys, and genitals.

This multiple organ dysfunction syndrome (MODS) may worsen and shutdown the lungs, a condition called acute respiratory distress syndrome, (ARDS), they said.

This, the researchers explained, happens due to the formation of a so-called hyaline membrane -- composed of debris of proteins and dead cells -- lining the lungs, which makes absorption of oxygen difficult.

Most deaths due to COVID-19 are therefore due to respiratory failure, they said.

The researchers explained that in the absence of a specific antiviral cure for COVID-19, the goal of treatment must be to the fight the symptoms, and lowering the mortality rate through intensive maintenance of organ function.

For example, an artificial liver blood purification system or renal replacement therapy can be used to filter the blood through mechanical means, they said.

The team noted that especially important are methods to supplement or replace lung function, for example with non-invasive mechanical ventilation through a mask, ventilation through a tube into the windpipe, the administration of heated and humidified oxygen via a tube in the nose, or a heart-lung bypass.

The researchers stressed the importance of preventing secondary infections.

They noted that SARS-Cov-2 also invades the intestines, where it causes inflammation and leakiness of the gut lining, allowing the opportunistic entry of other disease-causing microorganisms.

The researchers advocate that this should be prevented with nutritional support, for example with probiotics -- beneficial bacteria that protect against the establishment of harmful ones -- and nutrients and amino acids to improve the immune defences and function of the intestine.

"Because treatment for now relies on aggressive treatment of symptoms, preventative protection against secondary infections, such as bacteria and fungi, is particularly important to support organ function, especially in the heart, kidneys, and liver, to try and avoid further deterioration of their condition," Liu added.

As the COVID-19 wave sweeps strongly across the country, including in Tamil Nadu, mental health experts say the pandemic has triggered panic attacks among those who tested positive for the virus, causing bouts of depression and even driving some to the brink of suicide.

According to experts, nervousness, fear of contamination, panic attacks, constant reassurance seeking behaviour, sleep disturbance, excessive worry, feelings of helplessness and probability of an economic slowdown are the major factors leading to depression and anxiety among the people.

Potential job losses, financial burden, uncertainty about the future and fears of running out of food and necessities add to the worries.

Online platforms too have seen a growing number of people seeking help for mental health issues, ranging from anxiety and loneliness to concerns over productivity and job loss since the outbreak of COVID-19.

Director of Institute of Mental Health here, Dr R Purna Chandrika said towards April end about 3,632 calls were received and psychiatric counselling was provided to 2,603 callers.

"We have dedicated services at our centres in the districts and the calls meant for government medical college hospitals are routed to the respective institutions," she said.

Due to heavy virus caseloads, making this city the major contributor to the state's tally, the Greater Chennai Corporation too started a free helpline to help residents cope up with stress during the pandemic.

"From the psychological perspective, we don't find a single human being who is not feeling some degree of stress or anxiety due to coronavirus. The intensity and impact varies from person to person," said Lt Col N T Rajan, director of Chennai-based Mastermind Foundation.

The organisation is involved in free counselling throughout India ever since the first case of the deadly virus was reported in the country.

The foundation's recommendation on not to deploy the vulnerable in the police force, especially those above 50 years and women personnel with children below five years for COVID-19 related duty, was accepted and implemented by the Punjab government.

Psychiatrists feel that further worsening situations could lead to severe mental health issues, even triggering suicidal tendencies.

"Further worsening depression may lead to severe mental health issues and suicidal tendencies," said Dr S Senthil Kumar, a psychiatrist.

However, not all of them require medicines, he added.

"The situation is serious. There should be counselling at three stages--on coping with the virus, how to face it if tested positive and how to face life once treated and discharged from the hospital," Rajan said.

Awareness was of paramount importance, he said and warned the pandemic could cause panic attacks while in hospital or drive them to the brink of suicide.

Tamil Nadu, one of the worst affected states with a virus count in excess of 74,000 as of Friday, has witnessed a few instances of suicides allegedly related to COVID-19.

Hari Singh, owner of popular 'Iruttu Kadai' halwa shop in Tirunelveli, allegedly died by committing suicide on Thursday after being tested positive for COVID-19. He was 80.

Earlier in May, two COVID-19 patients in their 50s allegedly committed suicide in separate instances, at the government hospitals they were admitted to for treatment.

In the city corporation limits, a three-member team comprising a psychiatrist, counsellor and a social worker work for the respective zones.

"We direct certain sections of people like those with withdrawal symptoms and people requiring pills, to visit the doctor at their corporation zonal at a specific time, for medicines," a health worker of the civic body said.

Health platform, Lybrate reported an increase of 180 per cent in online patient consultations related to mental health on its platform between March 1 and June 20 across the country.

The largest increase came from Mumbai and Delhi, followed by Pune, Ahmedabad, Chennai and Bengaluru.

The biggest jump was witnessed in the age group of 25 and 45 years.

Tedros Adhanom Ghebreyesus, the World Health Organisation's (WHO) Director-General, said that a clinical trial of hydroxychloroquine (HCQ) on COVID-19 patients has come to "a temporary pause", while the safety data of the the anti-malaria drug was being reviewed.

According to the WHO chief, The Lancet medical journal on May 22 had published an observational study on HCQ and chloroquine and its effects on COVID-19 patients that have been hospitalized, reports Xinhua news agency.

The authors of the study reported that among patients receiving the drug, when used alone or with a macrolide, they estimated a higher mortality rate.

"The Executive Group of the Solidarity Trial, representing 10 of the participating countries, met on Saturday (May 23) and has agreed to review a comprehensive analysis and critical appraisal of all evidence available globally," Tedros said in a virtual press conference on Monday.

The review will consider data collected so far in the Solidarity Trial and in particular robust randomized available data, to adequately evaluate the potential benefits and harms from this drug, he said.

"The Executive Group has implemented a temporary pause of the HCQ arm within the Solidarity Trial while the safety data is reviewed by the Data Safety Monitoring Board. The other arms of the trial are continuing," Tedros added.

WHO initiated the Solidarity Trial, a plan to evaluate the safety and efficacy of four drugs and drug combinations against COVID-19 more than two months ago, which include HCQ.

According to the WHO, over 400 hospitals in 35 countries are actively recruiting patients and nearly 3,500 patients have been enrolled from 17 countries under the Solidarity Trial.

Tedros added that the safety concern over the drug related only to the use of HCQ and chloroquine in COVID-19, and "these drugs are accepted as generally safe for use in patients with autoimmune diseases or malaria".

"WHO will provide further updates as we know more," he added.