Cleaning our hands one ‘hit’ at a time

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.

Food with high water content is highly prescribed by doctors to stay hydrated during the summers, a season that summons a wave of soaring temperatures, higher than 40-degrees.

A much-loved fruit in India, apples are hydrating heros' in such a situation. A heatwave can affect human health in a varied manner and to maintain ideal body temperature in this soaring summer, one must remain adequately hydrated, be protected from the sun and maintain hygiene.

Working professionals and people who must step out in summers, are prone to the heatwave impact. Pediatric experts and doctors agree on the benefits of drinking water and eating fruits, especially, apples. 'An apple a day, keeps the doctor away' is true as they are rich in a number of vitamins with great anti-inflammatory benefits and many other essential minerals. Washington Apple Commission spells how apples can prove to be a summer-friendly fruit.

People often don't realise the danger of exposing themselves to extreme heat. Older adults, young children, and people with chronic illnesses are most at greater risk for serious problems. The nutrition benefits of apples may help not only in avoiding such illnesses but may also protect against many such conditions.

As popular as apples are as a fruit, they are enriched in antioxidants, dietary fibers, vitamins and a range of other nutrients that are greatly beneficial in maintaining good health. The fruit is rich in soluble fibers which may help prevent several health conditions and may lower the risk of major diseases such as heat strokes, diabetes and cancer.

The soluble fiber also promotes weight loss and improves gut health. The prebiotic effects of apples help feed the good bacteria in the gut, thus, improving digestion.

Apples are made of 85 percent water and contain vitamins, fibres and antioxidants. A high fibre content is a particularly beneficial property of apples, as improper digestion is a major health concern in the tropical climatic region. Apples are also enriched in antioxidants that help protect the lungs from oxidative damage and help oxygen flow through the blood.

Apple-based recipes

Make interesting snacks, dessert, beverages and savoury meals with this miraculous fruit during summers.

Salted apple caramel galette

Caramel apples get a grown-up makeover with this Salted Caramel Apple Galette. Warm, gooey, and delicious, this pastry is loaded with apples and homemade caramel. It's a sophisticated take on a childhood favorite and since it's easier to make than pie, it's perfect for summer get-togethers.

Caramel apple pie ice-cream sandwiches

Nothing is better at a cookout on a warm day than a cold, refreshing ice cream sandwich. In Caramel Apple Pie Ice Cream Sandwiches, the comforting flavor of apple pie is recreated in a creamy frozen banana-based ice cream studded with apple and date pieces. Then that scoop of ice cream is sandwiched between two pieces of no-bake cinnamon oat cookie dough.

New York, May 19: Cigarette smoke spurs the lungs to make more of the receptor protein which the novel coronavirus uses to enter human cells, according to a study which suggests that quitting smoking might reduce the risk of a severe coronavirus infection.

The findings, published in the journal Developmental Cell, may explain why smokers appear to be particularly vulnerable to severe COVID-19 disease.

"Our results provide a clue as to why smokers who develop COVID-19 tend to have poor clinical outcomes," said study senior author Jason Sheltzer, a cancer geneticist at Cold Spring Harbor Laboratory in the US.

"We found that smoking caused a significant increase in the expression of ACE2, the protein that SARS-CoV-2 uses to enter human cells," Sheltzer said.

According to the scientists, quitting smoking might reduce the risk of a severe coronavirus infection.

They said most individuals infected with the virus suffer only mild illness, if they experience any at all.

However, some require intensive care when the sometimes-fatal virus attacks, the researchers said.

In particular, they said three groups have been significantly more likely than others to develop severe illness -- men, the elderly, and smokers.

Turning to previously published data for possible explanations for these disparities, the scientists assessed if vulnerable groups share some key features related to the human proteins that the coronavirus relies on for infection.

First, they said, they focused on comparing gene activity in the lungs across different ages, between the sexes, and between smokers and nonsmokers.

The scientists said both mice that had been exposed to smoke in a laboratory, and humans who were current smokers had significant upregulation of ACE2.

According to Sheltzer, smokers produced 30-55 per cent more ACE2 than their non-smoking counterparts.

While the researchers found no evidence that age or sex impacts ACE2 levels in the lungs, they said the influence of smoke exposure was surprisingly strong.

However, they said, the change seemed to be temporary.

According to the data, the level of the receptors ACE2 in the lungs of people who had quit smoking was similar to that of non-smokers.

The study noted that the most prolific producers of ACE2 in the airways are mucus-producing cells called goblet cells.

Smoking is known to increase the prevalence of such cells, the scientists said.

"Goblet cells produce mucous to protect the respiratory tract from inhaled irritants. Thus, the increased expression of ACE2 in smokers' lungs could be a byproduct of smoking-induced secretory cell hyperplasia," Sheltzer explained.

However, Sheltzer said other studies on the effects of cigarette smoke have shown mixed results.

"Cigarette smoke contains hundreds of different chemicals. It's possible that certain ingredients like nicotine have a different effect than whole smoke does," he said.

The researchers cautioned that the actual ACE2 protein may be regulated in ways not addressed in the current study.

"One could imagine that having more cells that express ACE2 could make it easier for SARS-CoV-2 to spread in someone's lungs, but there is still a lot more we need to explore," Sheltzer said.