Researchers find link between early life adversity and opioid addiction

The deadly coronavirus that entered India while there was still nip in the air has beaten rising mercury, humid conditions, unique Indian genome and has entered monsoon season with more potency as fresh cases are only breaking all records in the country.

India recorded a single-day spike of record 24,850 new coronavirus cases on Sunday, taking its total tally to 6.73 lakh corona-positive cases.

Top Indian microbiologists were hopeful in March that after the 21-day lockdown, as summer approaches, the rise in temperature would play an important role in preventing the drastic spread of COVID-19 virus in India.

Several virologists hinted that by June this year, the impact of COVID-19 would be less than what it appeared in March-April.

The claims have fallen flat as the virus is mutating fast, becoming more potent than ever.

According to experts, the novel coronavirus is a new virus whose seasonality and response to hot humid weather was never fully understood.

"The theory was based on the fact that high temperatures can kill the virus as in sterilisation techniques used in healthcare. But these are controlled environment conditions. There are many other factors besides temperature, humidity which influence the transmission rate among humans," Dr Anu Gupta, Head, Microbiologist and Infection Control, Fortis Escorts Heart Institute, told IANS.

There is no built-up immunity to COVID-19 in humans.

"Also, asymptomatic people might be passing it to many others unknowingly. New viruses tend not to follow the seasonal trend in their first year," Gupta emphasized.

Globally, as several countries are now experiencing hot weather, the World Health Organization (WHO) reported a record hike in the number of coronavirus cases, with the total rising by 2,12,326 in 24 hours in the highest single-day increase since COVID-19 broke out.

So far over 11 million people worldwide have tested positive for the disease which has led to over 5,25,000 deaths, according to data from Johns Hopkins University. The US remained the worst-hit country with over 28 lakh cases, followed by Brazil with 15.8 lakh.

According to Sandeep Nayar, Senior Consultant and HOD, Respiratory Medicine, Allergy & Sleep Disorders, BLK Super Speciality Hospital in New Delhi, whether temperature plays a role in COVID-19 infection is highly debated.

One school of thought said in the tropical regions of South Asia, the virus might not thrive longer.

"On the other hand, another school of thought has found that novel Coronavirus can survive in a hot and humid environment and tropical climate does not make a difference to the virus. According to them, this is what distinguishes the novel coronavirus from other common viruses, which usually wane in hot weather," stressed Nayar.

Not much has been studied in the past and no definite treatment or vaccine is available to date.

"Every day, new properties and manifestation of the disease come up. As of now, the only way to prevent this monster is by taking appropriate precautions. Hand hygiene, social distancing, cough etiquette and face masks definitely reduce spread of COVID-19 infection," Nayar told IANS.

Not just top Indian health experts, even Indian-American scientists had this theory in mind that sunshine and summer may ebb the spread of the coronavirus.

Ravi Godse, Director of Discharge Planning, UPMC Shadyside Pennsylvania in the US told IANS in April: "In the summer, the humidity can go up as well, meaning more water drops in the air. If the air is saturated with water and somebody sneezes virus droplets into such air, it is likely that the droplets will fall to the ground quicker, making them less infectious. So the short answer is yes, summer/sunshine could be bettera.

According to Dr Puneet Khanna, Head of Respiratory Medicine and Pulmonology, Manipal Hospital, Delhi, COVID-19 death rates are not too different in tropical countries but since the disease affected them late it was yet to show its peak in these areas.

"The virus can survive well in hot and humid countries and this is proven now," he stressed.

Early treatment with the antiviral drug remdesivir has been found to reduce viral load and prevent lung disease in macaques infected with SARS-CoV-2 that causes COVID-19, according to a study.

The findings, published in the journal Nature on Tuesday, support the early use of remdesivir treatment in patients with COVID-19 to prevent progression to pneumonia.

Researchers from the National Institutes of Health in the US noted that remdesivir has broad antiviral activity and has been shown to be effective against infections with SARS-CoV and MERS-CoV in animal models.

The drug is being tested in human clinical trials for the treatment of COVID-19, they said.

Researcher Emmie de Wit and colleagues investigated the effects of remdesivir treatment in rhesus macaques, a recently established model of SARS-CoV-2 infection.

Two sets of six macaques were inoculated with SARS-CoV-2.

One group was treated with remdesivir 12 hours later -- close to the peak of virus reproduction in the lungs -- and these macaques received treatment every 24 hours until six days after inoculation.

In contrast to the control group, the researchers found that macaques that received remdesivir did not show signs of respiratory disease, and had reduced damage to the lungs.

Viral loads in the lower respiratory tract were also reduced in the treated animals; viral levels were around 100 times lower in the lower-respiratory tract of remdesivir-treated macaques 12 hours after the first dose, they said.

The researchers said that infectious virus could no longer be detected in the treatment group three days after initial infection, but was still detectable in four out of six control animals.

Despite this virus reduction in the lower respiratory tract, no reduction in virus shedding was observed, which indicates that clinical improvement may not equate to a lack of infectiousness, they said.

Dosing of remdesivir in the rhesus macaques is equivalent to that used in humans, the researchers noted.

They cautioned that it is difficult to directly translate the timing of treatment used in corresponding disease stages in humans, because rhesus macaques normally develop only mild disease.

However, researchers said the results indicate that remdesivir treatment of COVID-19 should be initiated as early as possible to achieve the maximum treatment effect.

Toronto, Feb 4: People who text while walking face a higher risk of an accident than those listening to music or talking on the phone, a study has found.

The study, published in the journal Injury Prevention, found that smartphone texting is linked to compromised pedestrian safety, with higher rates of 'near misses', and failure to look left and right before crossing a road.

Researchers from the University of Calgary in Canada call for a more thorough approach to exploring the impact of distracted pedestrian behaviours on crash risk.

Worldwide, around 270,000 pedestrians die every year, accounting for around a fifth of all road traffic deaths, according to the researchers.

'Pedestrian distraction' has become a recognised safety issue as more and more people use their smartphones or hand held devices while walking on the pavement and crossing roads, they said.

The researchers looked for published evidence to gauge the potential impact on road safety of hand-held or hands-free device activities.

This included talking on the phone, text messaging, browsing and listening to music.

From among 33 relevant studies, they pooled the data from 14 -- involving 872 people -- and systematically reviewed the data from another eight.

The analysis showed that listening to music wasn't associated with any heightened risk of potentially harmful pedestrian behaviours.

Talking on the phone was associated with a small increase in the time taken to start crossing the road, and slightly more missed opportunities to cross the road safely.

The researchers found that text messaging emerged as the potentially most harmful behaviour.

It was associated with significantly lower rates of looking left and right before or while crossing the road, and with moderately increased rates of collisions, and close calls with other pedestrians or vehicles, they said.

Texting also affected the time taken to cross a road, and missed opportunities to cross safely, but to a lesser extent, according to the researchers.

The review of the eight observational studies revealed that the percentage of pedestrians who were distracted ranged from 12 to 45 per cent, they said.

It also found behaviours were influenced by several factors, including gender, time of day, solo or group crossing, and walking speed.

The researchers acknowledge "a variety of study quality issues" which limit the generalisability of the findings.

"Given the ubiquity of smartphones, social media, apps, digital video and streaming music, which has infiltrated most aspects of daily life, distracted walking and street cross will be a road safety issue for the foreseeable future," the researchers noted.

"And as signage and public awareness campaigns don't seem to alter pedestrian behaviour, establishing the relationship between distracted walking behaviour and crash risk is an essential research need," they said.