India ranks second on list of shark fishing nations: WWF

Toronto, May 7: Scientists have uncovered how bats can carry the MERS coronavirus without getting sick, shedding light on what triggers coronaviruses, including the one behind the COVID-19 pandemic, to jump to humans.

According to the study, published in the journal Scientific Reports, coronaviruses like the Middle East respiratory syndrome (MERS) virus, and the COVID19-causing SARS-CoV-2 virus, are thought to have originated in bats.

While these viruses can cause serious, and often fatal disease in people, bats seem unharmed, the researchers, including those from the University of Saskatchewan (USask) in Canada, said.

"The bats don't get rid of the virus and yet don't get sick. We wanted to understand why the MERS virus doesn't shut down the bat immune responses as it does in humans," said USask microbiologist Vikram Misra.

In the study, the scientists demonstrated that cells from an insect-eating brown bat can be persistently infected with MERS coronavirus for months, due to important adaptations from both the bat and the virus working together.

"Instead of killing bat cells as the virus does with human cells, the MERS coronavirus enters a long-term relationship with the host, maintained by the bat's unique 'super' immune system," said Misra, one of the study's co-authors.

"SARS-CoV-2 is thought to operate in the same way," he added.

Stresses on bats, such as wet markets, other diseases, and habitat loss, may have a role in coronavirus spilling over to other species, the study noted.

"When a bat experiences stress to their immune system, it disrupts this immune system-virus balance and allows the virus to multiply," Misra said.

The scientists, involved in the study, had earlier developed a potential treatment for MERS-CoV, and are currently working towards a vaccine against COVID-19.

While camels are the known intermediate hosts of MERS-CoV, they said bats are suspected to be the ancestral host.

There is no vaccine for either SARS-CoV-2 or MERS, the researchers noted.

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"We see that the MERS coronavirus can very quickly adapt itself to a particular niche, and although we do not completely understand what is going on, this demonstrates how coronaviruses are able to jump from species to species so effortlessly," said USask scientist Darryl Falzarano, who co-led the study.

According to Misra, coronaviruses rapidly adapt to the species they infect, but little is known on the molecular interactions of these viruses with their natural bat hosts.

An earlier study had shown that bat coronaviruses can persist in their natural bat host for at least four months of hibernation.

When exposed to the MERS virus, the researchers said, bat cells adapt, not by producing inflammation-causing proteins that are hallmarks of getting sick, but instead by maintaining a natural antiviral response.

On the contrary, they said this function shuts down in other species, including humans.

The MERS virus, the researchers said, also adapts to the bat host cells by very rapidly mutating one specific gene.

These adaptations, according to the study, result in the virus remaining long-term in the bat, but being rendered harmless until something like a disease, or other stressors, upsets this balance.

In future experiments, the scientists hope to understand how the bat-borne MERS virus adapts to infection and replication in human cells.

"This information may be critical for predicting the next bat virus that will cause a pandemic," Misra said.

Bengaluru, Mar 13: In the wake of fresh cases of Covid-19 reported in Karnataka, Infosys Foundation chairperson Sudha Murty has urged the Karnataka government to take steps to shut malls and theatres, saying the coronavirus multiplies in air-conditioned areas.

In a letter to the government, she said preventive measures should be taken to control the spread of coronovirus before it gets worse.

Murty, who also leads the State government-constituted Karnataka Tourism Task Force, said she has discussed the current situation with Chairman and Executive Director of Narayana Health, Devi Prasad Shetty.

She suggested closure of all schools and colleges with immediate effect, malls, theatres and “all air-conditioned areas where the virus multiplies”, and allow only essential services like pharmacy, grocery and petrol bunks.

“It is not scientifically proven that the virus dies in high temperature,” she said pointing to spread of the virus -- despite heat -- in peak summer in Australia and Singapore, which have “summer all 12 months”.

“I request you to vacate one government hospital with at least 500 - 700 beds for this purpose (to deal with coronavirus cases), which requires oxygen lines and pipes,” she said.

“Infosys Foundation, the philanthropic and CSR arm of software major Infosys, would do the civil work and Devi Shetty has agreed to share resources like medical equipment,” she added.

“We would like to work with the government proactively so that we can prevent this as early as possible,” Sudha Murty said.

The total number of confirmed coronavirus positive cases in Karnataka is five, including the 76-year old man from Kalaburagi who died on Tuesday night.

Kozhikode, Apr 4: In a bid to maintain the lockdown amid COVID-19 outbreak, Police in Kozhikode is monitoring the situation using drone cameras and making sure that people are not breaking the law.

The police have so far arrested 41 persons who were out on a morning walk on Saturday during the lockdown in the backdrop of coronavirus outbreak.

The SHO of Town South Police Station informed that the accused were later released on bail.
At least 295 cases have been reported in the state so far.

Talking about COVID-19 testing, State Health Minister KK Shailaja told media: "Nine labs are conducting polymerase chain reaction (PCR) tests in Kerala. We've received 2000 rapid test kits and will start rapid tests from tomorrow. If a person tests positive in rapid test, we need to confirm it with PCR test."

The total number of COVID-19 positive cases in India climbed to 3072 on Saturday, according to Ministry of Health and Family Welfare.