Salut, Covid-19, Vacunes
According to a video circulated via WhatsApp, the American Red Cross has allegedly claimed that people who have been vaccinated against covid-19 cannot donate plasma to treat others infected with SARS-CoV-2, as the vaccine "destroys the patients' natural antibodies". This is DECEITFUL. The American Red Cross has stated that not all patients can be admitted at the time to donate plasma from a convalescent, but this depends more on the type of vaccine that has been administered than on whether or not the vaccine has been received. In any case, donation is not refused, but in certain cases it is requested to be delayed for two weeks for some types of vaccines.
"Those people who have received covid-19 vaccine can not donate plasma from convalescent [...] since, although plasma is made from antibodies from people who have already recovered from the virus, the vaccine eliminates them, making convalescent plasma ineffective in other covid-19 patients".
The American Red Cross has issued a statement clarifying that it is not denying plasma donations from convalescents to patients who have been previously vaccinated but is setting waiting times for specific cases. “We are following the US Food and Drug Administration (FDA) donor admission guide for those who have received a vaccine against covid-19”, they say on their website. “Waiting times [for donation] can vary depending on the type of vaccine administered”, they add.
To confirm that the volunteer is suitable to donate blood, the organisation is asking for the vaccinated record. Thus, they clarify that patients vaccinated with injections from AstraZeneca, Janssen/J&J, Moderna, Novavax (not yet approved) or Pfizer, are perfectly admissible.
The delays are for candidates who have already received injections with the attenuated virus (none of those approved in the United States or Europe are attenuated), who do not know what vaccine they received, or who cannot prove what type of drug they have been inoculated with. In these three cases, the person is not permanently excluded from the process, but must wait two weeks before donating blood.
What is completely false is that behind this extension of vaccination is the reason given in the video: that the vaccine erases the antibodies naturally generated by the individual. “For a person who has had the disease, the recommendation is that, donating or not, to receive only one dose, not two, because what it does is remind the immune system to produce antibodies," Cristina Arbona, a member of the Spanish Society of Haematology and Hemotherapy (SEHH, in Spanish) and director of the Transfusion Centre of the Valencian Community, told to Verificat.
In reality, this delay responds more to the health safety issues: “Attenuated viruses can replicate and if you give plasma or platelets to an immunosuppressed person, you can cause a disease if the virus replicates. It is a safety measure for the receptor”, says the expert, who adds that, in fact, this does not only happen with vaccines against covid-19. "This recommendation to limit donation to one or two weeks after administration of the vaccine applies to any injection against any type of virus that is made with attenuated virus," she concludes.
At the beginning of the SARS-CoV-2 pandemic, plasma started to be used to treat covid-19 patients. It is a compound obtained from the donor's blood, from which the blood cells are removed, separating the liquid (plasma) and the antibodies. With no alternative treatment available, it has been used to treat covid-19 patients, although so far no research has been able to prove that it actually reduces mortality in severe patients. However, there are still doubts in earlier stages of the disease, says Arbona.
The discoverer of convalescent plasma, Emil Adolf von Behring,received the first ever Nobel Prize in Medicine in 1901. However, "today, the efficacy of antibiotics and other treatments makes it unnecessary to administer convalescent plasma to treat any disease," she says. Plasma is generally used when a patient has suffered severe burns or has lost a lot of blood, but not for a specific disease.
Aquest article és part del projecte "Les Mentides Amenacen la Salut", el primer portal de fact-checking de rumors sobre la covid-19 de Catalunya.