Covid still evolving, mutants may surpass immune response, warn Experts

New Delhi: As the Covid related restrictions are taken off, an upsurge in the flu cases have raised concerns as Experts warn of the evolution and adaption of the virus to cause newer variants which are able to surpass human immune response.

"Still new to mankind, Covid virus is showing a continuous evolution in a short time period, throwing off multiple variants and recombinants. Through mutations, each successive generation is able to escape the human immune response generated to its previous version. After the Omicron era, the possibility of an all-new variant arriving is keeping scientists on the alert," said Dr Rajeev Jayadevan, Co-Chairman, National Covid Task Force of the Indian Medical Association (IMA) while explaining the phenomenon.

Jayadevan said influenza and RSV (respiratory syncytial virus) are other bugs that cause significant respiratory illnesses. They spread from person to person and respond to the same precautions that are followed against Covid-19.

Unlike Covid-19 which is caused by one virus, influenza is caused by a group of several viruses, which vary from year to year. Influenza viruses can live in birds as well as pigs, which helps increase their diversity, Jayadevan said.

He added: "RSV causes cold like symptoms, and is mostly harmless in older children. It can potentially cause severe illness in very young babies, who have tiny airways. There was a surge in RSV in many countries following the worldwide relaxation of pandemic restrictions."

There are several common cold-causing viruses, such as rhinovirus and adenoviruses as well as common cold-causing coronaviruses. Their mortality rate is low, and only basic preventive and supportive measures are needed.

Talking about the Indian ecosystem, Jayadevan said that another virus that causes concern is the dengue virus. Unable to directly spread from person-to-person, the dengue virus uses a vector or vehicle to travel from person-to-person: the Aedes mosquito. As the mosquito drinks an infected person's blood, viruses get inside the mosquito's gut and then travel to its salivary glands. When this mosquito bites a healthy person, the virus enters that person's body - through the mosquito's saliva.

"The most important aspect of dengue prevention is mosquito and larva control. The dengue Aedes mosquito bites during daytime and lays eggs in freshwater. Eliminating stagnant water, even small puddles in the locality is important", he said, adding that Hepatitis A and E are illnesses of the liver caused by viruses that spread easily in communities by the feco-oral route, causing jaundice. Fecally contaminated water is the medium of travel of the virus from person to person.

While talking about the Indian perspective of viruses outbreak, Dr Sharwari Dabhade Dua, Endocrinologist, Madhukar Rainbow Children's Hospital, said various flu-like influenza, enterovirus, rhinovirus and swine flu are rising in the country.

Tomato flu, which is caused by coxsackievirus, is also on the rise in the southern part of the country and is common in children, although adults, too, can be infected.

-IANS Inputs