Can convalescent Plasma therapy from recovered coronavirus patient treat infected people?

New Delhi, Apr 07: As the novel coronavirus that has killed hundreds of thousands of people around the world and are getting sick with covid-19 every few days, several new experimental therapies are being proposed and tested by medical researchers, including anti-viral drugs which can kill viruses.

So far, there's no vaccine, and no drug known to work to reverse the illness cause by the novel coronavirus.

But Researchers have now explored one potentially promising treatment to help people infected with the coronavirus.

The convalescent plasma (CP) therapy was conducted on 10 adult patients with severe COVID-19, aged 34-78 years.

The results of the pilot study suggest that CP therapy may be a safe and promising therapeutic option for severe COVID-19 infections. By giving patients plasma or serum from patients who have developed antibodies to a particular virus or bacteria, an infected patient is given a massive boost to their adaptive immune system, which confers passive immunity.

The use of convalescent plasma is not a new concept. The concept, introduced by a German immunologist Emil von Behring, has existed since 1890, and has been widely applied for the treatment of different infectious diseases including mumps, measles and polio etc.

This treatment modality has previously been used as a desperate last resort step during Ebola outbreaks of 2014, and also in the Severe Acute Respiratory Syndrome (Sars) and Middle East Respiratory Syndrome (Mers).

The treatment is based on the function of antibodies, proteins created by the immune system that combat invaders to the body in a variety of ways. Some are capable of neutralizing a virus, while others work by mobilizing a range of other immune cells that fight off disease. It's not yet known by which mechanism COVID-19 antibodies might work, but the thinking is that an infusion of convalescent plasma may boost a generalized response, known as passive immunity, until a patient develops a strong, targeted ability to fight the virus.

During the Spanish influenza pandemic of 1918 convalescent plasma was used as a potential therapy with mixed results. It has been used in a variety of viral infections, although studies have been small and inconclusive. One success was the use of convalescent serum to treat Ebola virus.

Meanwhile, two elderly South Korean coronavirus patients recovered from severe pneumonia after being treated with plasma from survivors, researchers said Tuesday, offering hope in the face of the global pandemic.

Scientists have pointed to the potential benefits of plasma -- a blood fluid -- from recovered individuals who have developed antibodies to the virus enabling the body''s defences to attack it.

Dengue virus

In the case of dengue, getting convalescent serum makes the patient's paradoxically worse, as it causes the virus to replicate.

Other known complications include transfusion-associated reactions seen with any blood transfusion. There is also the possibility that other known or unknown pathogens could be introduced into the patients.