No return to old normal in foreseeable future: WHO chief

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.

Singapore, May 25: COVID-19 patients are no longer infectious after 11 days of getting sick even though some may still test positive, according to a new study by infectious disease experts in Singapore.

A positive test "does not equate to infectiousness or viable virus," a joint research paper by Singapore's National Centre for Infectious Diseases and the Academy of Medicine, Singapore said. The virus "could not be isolated or cultured after day 11 of illness."

The paper was based on a study of 73 patents in the city-state.

The latest findings may have implications on the country's patient discharge policy. The discharge criteria is currently based on negative test results rather than infectiousness.

Singapore's strategy on managing COVID-19 patients is guided by the latest local and international clinical scientific evidence, and the Ministry of Health will evaluate if the latest evidence can be incorporated into its patient clinical management plan, according to a report by the Straits Times.

So far, 13,882, or about 45% of the total 31,068 Covid-19 patients in Singapore have been discharged from hospitals and community facilities. Singapore reported 642 new Covid-19 cases as of noon on Saturday.

The government has been actively screening pre-school staff as it prepares to reopen pre-schools from June 2. On Friday, two pre-school employees tested positive for the novel coronavirus, bringing the total number of confirmed cases among pre-school staff to seven, according to the Ministry of Health.

Washington D.C., Jan 25: A new study conducted by a team of researchers reveals why individuals who have a history of early life adversity (ELA) are disproportionately prone to opioid addiction.

The study conducted examined how early adversities interact with factors such as increased access to opioids to directly influence brain development and function, causing a higher potential for opioid addiction.

The study was lead by UCI researchers and was published in Molecular Psychiatry.

Tallie Z. Baram, MD, PhD, the Danette Shepard Chair in Neurological Sciences at the UCI School of Medicine and one of the senior researchers for the study, was on the take that the widely known factor genetics that plays major role in addiction vulnerability, cannot be solely held responsible for the recent rise in opioid abuse.

To further clarify, the researchers simulated ELA in rats by limiting bedding and nesting materials during a short, postnatal period of time.

In female rats, this led to striking opioid addiction-like characteristics including an increased relapse- behaviour, for example.

As observed in addicted humans, the rats were willing to work very hard (pay a very high price) to obtain the drug.

Baram said: "Ultimately, we found that conditions during sensitive developmental periods can lead to vulnerability to the addictive effects of opioid drugs, especially in females, which is consistent with the prevalence of ELA in heroin-addicted women."

These findings can be used to highlight the importance given to sex differences in future ELA-related studies on opioid addiction, and in future prevention or intervention strategies being developed to address the growing opioid crisis.

The study conducted examined how early adversities interact with factors such as increased access to opioids to directly influence brain development and function, causing a higher potential for opioid addiction.

The study was lead by UCI researchers and was published in Molecular Psychiatry.

The study found that unpredictable, fragmented early life environments may lead to abnormal maturation of certain brain circuits, which profoundly impacts brain function and persists into adolescence and adulthood.

Tallie Z. Baram, MD, PhD, the Danette Shepard Chair in Neurological Sciences at the UCI School of Medicine and one of the senior researchers for the study, was on the take that the widely known factor genetics that plays major role in addiction vulnerability, cannot be solely held responsible for the recent rise in opioid abuse.

To further clarify, the researchers implanted ELA in rats by limiting bedding and nesting materials during a short, postnatal period of time.

In female rats, this led to striking opioid addiction-like characteristics including an increased relapse- behaviour, for example.

As observed in addicted humans, the rats were willing to work very hard (pay a very high price) to obtain the drug.

Baram said: "Ultimately, we found that conditions during sensitive developmental periods can lead to vulnerability to the addictive effects of opioid drugs, especially in females, which is consistent with the prevalence of ELA in heroin-addicted women."

These findings can be used to highlight the importance given to sex differences in future ELA-related studies on opioid addiction, and in future prevention or intervention strategies being developed to address the growing opioid crisis.