While drug combos are being used to slow down the spread, plasma transfusion from recovered patients is another option

With a possible vaccine still months away, there’s a glimmer of hope. Apparently, a temporary measure touted to be a “promising rescue option” is being explored to treat critically ill patients, our frontline healthcare workers and those at high risk. Researchers have found tentative evidence in a century-old blood transmission treatment that may help us at least slow the spread of the disease. The process involves the infusion of blood plasma cells, collected from patients who have recovered from the disease, to those critically ill. What this reliable stopgap measure does is that it buys enough time for the patients to stabilise and recover. The antibodies so injected into the patient’s body act as a booster, thus increasing his/her immunity, which helps the body to be better prepared to be exposed to the impacts of SARS-CoV-2. China has already made use of this plasma therapy with five critically ill patients, including women, all aged between 35-65, showing striking improvements. In the US, too, trials on two patients were conducted and now, the New York Blood Center is collecting blood plasma donations from convalescent COVID-19 patients for therapeutic use in New York City, the new epicentre of the pandemic. Depending on the test results, which would depend on three parameters, namely whether the plasma can prevent infection in COVID-19 patients by a close contact; can keep people with moderate symptoms from needing intensive care; and can it help cure those critically ill, the FDA would give a further green signal for wider use. In the UK, too, the national blood service has started screening blood from patients to find plasma rich in antibodies to use in those trials. Thankfully, India does have facilities to derive plasma from blood cells but is yet to receive a heads up from the Drug Controller General of India. Much will depend on the experiments carried out in these nations. Though there’s enough evidence for it to be used for treatments but for the lack of any definitive answers, it is being used for emergency cases only. 

While we await a conclusive result, it is some relief to know that this method, also known as convalescent plasma/sera, is known to have worked wonders in curing past epidemics such as mumps and measles. Even COVID-19’s foremost predecessor like H1N1, Ebola and SARS were fought with this passive immune therapy, though with inconsistent success. What is learnt from these experiences is the fact that downsides, too, exist. Some patients could recover, others could not. This is why the therapy is being treated as “experimental” and is being used for “emergency” cases only. Primarily, it runs the risk of transmitting other kinds of diseases to the patient which might aggravate matters. Besides, with the antibodies present in donors varying, a process to pool in concentrated and consistent dose will need to be developed. It is, however, soothing that the process makes use of everyday equipment that is normally found in hospitals and blood-bank facilities. What will be troublesome is for nations to find convalescents eligible for plasma donation. For doctors, it would be essential to find the right kind of plasma, one that has the highest concentration of neutralising antibodies. Nevertheless, until a long-term strategy is found, we can at least buy time for COVID-affected patients.