‘Prolonged Covid infection reactivates dormant viruses in body’

Long-term exposure to Covid-19 infection may reactivate dormant viruses in the patients, leading to multiple medical complications, according to South Korea-based Indian scientist Prof Ram Upadhayaya, who is medicinal scientist, infectious diseases and oncology, and visiting professor at Kwangwoon University, Seoul. He spoke to TOI on this issue.

Excerpts:

Is there any study on prolonged Covid-19 infection? How many people suffer from it?

A study published in science journal ‘Nature’ shows that about 30% of patients developed Covid related complications after contracting (SARS)-CoV-2 infection.

What are the reasons behind it?

It is the result of immune system dysfunctioning and reactivation of viruses such as Epstein-Barr virus (EBV), human cytomegalovirus (CMV) and herpes simplex. In many Covid cases, they get reactivated from their usual dormant state after Covid infection. EBV is found in the bone marrow of 90% of people, CMV in 60% of people and herpes simplex in 50% of individuals in the dormant state. Herpes and CMV are found in various body parts.

What are the symptoms of infections from these viruses?

Symptoms include fatigue, blood disorders, heart problems (myocarditis, inflammatory cardiomyopathy and heart attack) and neurological issues including stroke and hemorrhage. Clinical studies have shown reactivation of EBV in 66.7% of Covid patients. Similarly, CMV and herpes simplex have been triggered by (SARS)-CoV-2. They are responsible for prolonged Covid symptoms and target different body organs. EBV can even lead to hearing loss, blood disorders including blood cancer, and nasopharyngeal cancers.

Are there any similarities with other diseases?

Reactivation of these viruses can result in overlapping symptoms, specially like coinfection of dengue. Doctors often prescribe symptomatic treatment which gives temporary relief but the situation gets aggravated.

How should the infection be treated?

Medical screening of patients who suffered from Covid should be done for reactivation of EBV, CMV, herpes, and other viral infections. The screening methods are easily available. Besides, tests to check immune system response should also be performed on such patients. Since treatment is available for these viral infections, they can be treated more efficiently.

What should be the future strategy to deal with issues associated with Covid?

To win Covid battle, B cell memory-based vaccines should be made as existing vaccines provide immunity for nearly up to nine months. Besides, more BSL 3 and BSL 4 labs should be set up so that future pandemics can be tackled more efficiently.