Scientists developing tool to help differentiate between bacterial and viral infections

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.

The COVID-19 pandemic and the subsequent lockdown saw many people turning chefs overnight, but those who could not turned to online delivery of food. And not just any food, as per a new report, Indians "craved the most for Biryani" during the lockdown.

The "StatEATistics report: The Quarantine Edition" from food delivery platform Swiggy found that Indians ordered biryani over "5.5 lakh times" from their favourite restaurants.

The new normal might have opened a pandora's box of behavioral changes, but some old habits die hard like the love for Biryani, which took the top spot for overall orders. It was followed by butter naan and masala dosa at 3,35,185 and 3,31,423, respectively.

Biryani has topped the list of most ordered dishes for the fourth year in a row, the food delivery platform noted.

Indians didn't forget to indulge their sweet tooth in the uncertain months of lockdown. Their favourite comfort food during the lockdown period was the moist and decadent Choco Lava cake, ordered around 1,29,000 times.

"The humble Gulab Jamun (84,558) and chic Butterscotch Mousse cake (27,317) followed suit," said the report derived from Swiggy's order analysis in the past few months across cities that it is present in.

Also, as birthday parties moved to video calls, and virtual cake cutting sessions, according to the food delivery platform, it delivered nearly "1,20,000 cakes" to complete these celebrations.

According to the report, on average, "65,000 meal orders" were placed by 8 pm each day to make sure food arrived in time for dinner.

"It was the busiest hour for Swiggy delivery partners and restaurants. On average, they (customers) chose to tip Rs.23.65, with one particularly generous customer tipping Rs. 2500!," it added.

For those who only relied on home-made food during the quarantine, Swiggy delivered a whooping 323 million kgs of onions and 56 million kgs of bananas through its grocery section and hence ensured that its consumers were all stocked up.

That said, it also took care of the 'quick-fix meal' tribe -- consumers who resort to the evergreen college hacks of living on instant noodles.

"Around 3,50,000 packets of this ideal easy to cook meal were ordered during the lockdown," it said.

In all, Swiggy delivered 40 million orders across food, groceries, medicines and other household items during India's lockdowns. It also delivered over 73,000 bottles of sanitizers and hand wash along with 47,000 face masks as the definition of essentials' changed during these uncertain times.

Mar 6: The spread of the new coronavirus is shining the spotlight on a little-discussed gender split: men wash their hands after using the bathroom less than women, years of research and on-the-ground observations show.

Health officials around the world advise that deliberate, regular handwashing is one of the best weapons against the virus which causes a flu-like respiratory illness that can kill and has spread to around 80 countries.

The Centers for Disease Control and Prevention's online fact sheet "Handwashing: A corporate activity," cites a 2009 study that finds "only 31% of men and 65% of women washed their hands" after using a public restroom.

Social media comments about men's handwashing lapses forced an august British institution to caution visitors about bathroom behaviour this week.

After author Sathnam Sanghera complained on Twitter about "grown," "educated" men in the British Library toilets not washing their hands, the library responded, putting up additional signs reminding patrons to wash their hands in men's and women's bathrooms.

Thanks to "visitor feedback," a spokesman told Reuters, "we have increased further the number of posters in public toilets so that visitors are reminded of the importance of good hygiene at exactly the point where they can wash their hands."

Men and women approach handwashing after using the restroom differently, according to multiple surveys and field studies.

"Women wash their hands significantly more often, use soap more often, and wash their hands somewhat longer than men," according to a 2013 Michigan State University field study conducted by research assistants who observed nearly 4,000 people in restrooms around East Lansing, Michigan.

The study found 14.6% of men did not wash their hands at all after using the bathroom and 35.1% wet their hands but did not use soap, compared to 7.1% and 15.1% of women, respectively.

"If you stand in the men's bathroom at work, and watch men leave, they mostly don't wash their hands if they used the urinal," said one New York City public relations executive, who did not want to be identified for fear of alienating his colleagues.

Since the virus's spread, he's seen an uptick in men's handwashing at work, he noted. "I, for the record, do wash my hands all the time," he added.

Female medical staff in critical care units "washed their hands significantly more often than did their male counterparts after patient contact," a 2001 study published in the American Journal of Infection Control found.

Middle-aged women with some college education had the highest level of knowledge about hand hygiene, a survey published in 2019 by BMC Public Health, an open access public health journal, found.

Early information about coronavirus infection in China shows that men may be more susceptible to the disease. Just over 58% of the more than 1,000 COVID-19 patients reported in China through Jan. 29, 2020, were male, research published in the New England Journal of Medicine shows.

Researchers have not linked the difference to hand hygiene.