Expert Description: How Poliovirus Is Similar (or Different) To Coronavirus

A world overwhelmed by the flow COVID-19 In a pandemic, it is easy to forget the presence of other viruses that can cause serious illness. One such virus that has affected our lives since the time of Egyptian civilization is poliovirus. Every October 24th is World Polio Day, celebrating the birth of Jonas Salk, an American researcher who developed the first polio vaccine in 1955.

Poliovirus is the simplest known human virus. It is very small, only 30 nanometers. By comparison, SARS-CoV-2 is a slightly larger virus of about 100 nanometers.

Poliovirus was first isolated in 1909 by Karl Landsteiner, Erwin Popper, and the first humans. coronavirus Quarantined by Leland David Bushnell and Karl Alfred Brandon in 1933.

Poliovirus causes a disability and life-threatening illness called polio. The virus spreads from person to person and can infect the human spinal cord and cause paralysis. Approximately 25% of all people infected with polio cause very mild flu-like symptoms such as sore throat, fever, malaise, nausea, headache, and stomach for about 2-5 days and recover completely. increase.

However, in a small proportion, infected individuals can develop “pins and needles” or other symptoms such as tingling and tingling in the arms and legs, meningitis, and paralysis of the arms and legs. Children under the age of 5 are at greatest risk of developing serious poliovirus-related complications that affect their quality of life.

Poliovirus is highly contagious and can easily spread from person to person. The R-naught value, that is, the number of people who can be infected with polio by one infected person is 5 to 7. For Covid-19, the R-naught value is 1.4 to 3.9.

Poliovirus spreads through person-to-person contact, especially through the fecal-oral route. Poor hand hygiene, lack of access to clean water, and inadequate sewage systems are the most common reasons for polio outbreaks and infections. However, in the 1950s, the first polio vaccine was invented by Jonas Salk. This is a very safe and effective inactivated poliovirus vaccine, given by injection.

It was very effective, but at the time, disposable syringes were rarely available and immunization was slow. Another polio vaccine invented by Albert Sabin in 1961 was called the Oral Polio Vaccine (OPV). It was easier and easier to administer to many people. The combination strategy was decided and high doses were started. Polio eradication is one of the most ambitious global health initiatives in history, making polio the second most eradicated human disease in history (originally smallpox).

Today, Pakistan and Afghanistan are the only places in the world where wild polio exists. The successful use of this vaccine has reduced the number of polio cases from Rs 35,000 in 1988 to 33 in 2018.

Polio is highly contagious, so no one is safe until everyone is vaccinated. Since the introduction of the Global Polio Eradication Initiative (GEPI) in 1988, due to the rigorous efforts of the Ministry of Health and the Ministry of Family Welfare to monitor poliovirus sewage samples and a strong immunization program as a public-private partnership with Rotary International. , This has happened. The vaccination program was a great success. As of March 27, 2014, India has been declared polio-free.

Since the development of the polio vaccine, the science of vaccine development and understanding of the immune system have improved significantly. In the field of vaccine science, researchers have been working for decades on how to design and develop safer, more effective and cheaper vaccines.

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A variety of safe and effective vaccines against Covid-19 have been developed around the world using classic vaccine development techniques and the latest state-of-the-art technology.

Designing strategies, developing vaccines, and testing their safety and efficacy is a tedious, time-consuming and costly process. However, in the days of Covid-19, vaccine developers had decades of data, a wealth of volunteers, and sufficient funding to study the effectiveness of various vaccines. With the cooperation of scientists, regulatory agencies and vaccine makers, multiple vaccines against Covid-19 have become available in such a short period of time.