Blood transfusions from COVID-19 survivors to treat current sufferers
Hospitals in New York are preparing for an increase in blood transfusions from people who have recovered from COVID-19 in order to treat people currently suffering from the disease. This century-old approach of transferring blood from previously infected individuals is hoped to deliver the antibodies needed to fight off the virus.
As cases of coronavirus in the US rise, researchers are looking to history for ways to address the global outbreak. In 1918, the world saw the H1N1 influenza pandemic within which 1,700 patients were given blood from survivors and successfully recovered. Other examples of successful serum transfusion to treat viral disease include Ebola and severe acute respiratory syndrome (SARS).
This technique, termed ‘passive antibody therapy’ is seen to work primarily in individuals in early stage disease as the virus is relatively contained within the hosts blood. The word ‘passive’ refers to the method of antibody production, as the person receives these externally rather than generating an immune response themselves. The US effort follows preliminary studies in China which involved transfusing convalescent plasma – the fraction of blood which contains antibodies but not red blood cells – into patients suffering from COVID-19. Unfortunately, with no definitive results so far, the likelihood of success is still unknown.
The advantage to this technique is that plasma is available immediately and is relatively safe to infuse, provided it is screened for disease and infectious agents. Drugs and vaccines take several months, to several years to develop; even with the special status given to find a vaccine against COVID-19, it must go through several rounds of vigorous trials in order to be deemed safe. The New York governor Andrew Cuomo announced the use of COVID-19 convalescent plasma in the treatment of infected individuals as early as next week. These individuals will be monitored closely for the slightest of changes in their condition.
If results are promising, it is hoped the second rollout of transfusions will be offered to medical professionals (nurses, physicians), who are at a high risk of developing COVID-19. This would serve as a mechanism to provide passive immunity, allowing them to remain in hospitals without risk of infection. This is important as hospitals around the world are at a huge threat of workforce depletion.
The FDA has recently classified convalescent plasma as an ‘investigational new drug’, allowing researchers to propose ways of using it in clinical trials, and also allows doctors to use it to treat serious COVID-19 infections for which no other treatment works. The hope is that as this method gains more approval and popularity, hospitals all over the world will follow.