It is human nature to use any option as the last resort when there are no other options left or when they have failed. The coronavirus has been the scourge for man since it emerged in late December 2019. There are no proven vaccines or medicines at present, although doctors and scientists all over the world are scrambling to develop drugs or vaccines for the disease. And plasma therapy has proved to be a boon for coronavirus patients. Plasma therapy, or convalescent plasma therapy in medical parlance, is a method of treatment in which the plasma of a person who has recently recovered from a disease is transfused into the blood of the patient suffering from the same disease. In case of coronavirus patients, the plasma of the patient who has recently recovered from the disease is transfused into the blood of another critically ill coronavirus patient.
Antibodies Plasma is the liquid part of blood. Yellowish in colour, it is composed of 90 per cent of water. Other parts of blood are erythrocytes (red blood cells), leukocytes (white blood cells) and thrombocytes (platelets). There are antibodies in the plasma. When a patient recovers from the coronavirus, there are still antibodies in his or her plasma. The antibodies have coronavirus-fighting properties. When the plasma is transfused into the blood of some other coronavirus patient, he or she receives the antibodies and develops passive immunity to fight the disease. Plasma therapy is not a universal method of treatment but is being practised not only in Nepal but also in many other countries. This therapy was first used in late July in Nepal. A 60-year-old man received the treatment and got well. Since then, many coronavirus patients have benefited from the treatment. The coronavirus is a novel disease. Nobody had been exposed to the virus before its outbreak in Wuhan and had antibodies to fight the disease. As no other alternatives - proven vaccines or drugs - are available, doctors have resorted to plasma therapy. The therapy is based on the concept of passive immunity, an immunity that is developed through the antibodies received from others. Doctors around the world are experimenting with this therapy. But they are not sure whether such ‘borrowed antibodies’ can help the severely ill patients in fighting the disease. However, they are using it as a trial case. This is not the first time that plasma therapy has been used in the medical field. Plasma therapy, which is usually used as a pis aller, has been used to cure people suffering from various diseases like influenza A (H1N1), SARS, MERS and Ebola. The therapy has also been used to treat such diseases as measles, mumps, poliomyelitis and flu. It may be noted that the plasma of not all those who have recovered from the coronavirus can be transfused into the blood of severely ill coronavirus patients. As per doctors, those recovered patients who are eighteen to sixty years of age are fit for plasma donation. But such persons should not have any underlying conditions such as diabetes, hypertension, HIV, hepatitis B and C or other chronic ailments. Further, both the donors and patients should have the same blood group. In case of female donors, those who have not undergone pregnancy are preferred. The antibodies in the plasma of those with a history of pregnancy may harm the recipients. So male donors are generally preferred to female ones as their plasma is safer than that of female donors. After male donors, female donors with no history of pregnancy are preferred. As some female donors may hide their pregnancy history, they are not usually chosen for plasma donation in the county. Plasma therapy is beneficial for high-risk people such as members of the family of a coronavirus patient or healthcare workers who have to serve their patients virtually round the clock. They can boost their immunity power through the antibodies received from the coronavirus-recovered patients. The Nepal Red Cross Society is collecting the blood samples of the coronavirus recovered patients for plasma therapy at the request of the Nepal Health Research Council. The Nepal Red Cross Society and the Nepal Medical Association have inked an agreement to establish a plasma bank. According to the agreement, the former shall manage technical manpower and logistics like plasma bags and other requisite materials, while the latter shall provide the former with the record of coronavirus-recovered patients and coordinate with the former in blood collection. Although plasma therapy is showing good results, more research needs to be done to establish its efficacy beyond doubt. There could be several risks associated with this therapy. As blood transfusion is involved in this therapy, a virus already existing in the blood of a coronavirus-recovered patient may be unknowingly transferred to the recipient. So the health condition of the recovered patient needs to be thoroughly checked up before blood transfusion. Further, this process may not be fit for all patients. It may be difficult for the elderly with a weak heart and lungs to endure receiving a large volume of plasma. That is why plasma therapy needs to be administered under strict medical supervision.
A ray of hope Although it holds out a ray of hope in the treatment of coronavirus patients, plasma therapy can be considered merely an expedient method of treatment. It gives passive immunity to patients in sharp contrast to vaccines that generate active immunity in people. Some countries like the USA, the UK, China and India are using this therapy. The use of this therapy is expected to bring down the mortality rate. Until effective vaccines are developed and easily made available, plasma therapy should be taken as a last resort in the treatment of coronavirus patients.