New research: Transplant recipients remain vulnerable to Covid-19 even after two vaccine doses

The new study evaluated this immunogenic response following the second dose of either the Moderna or Pfizer-BioNTech vaccine for 658 transplant recipients, none of whom had a prior diagnosis of Covid-19.

 

In a study published in JAMA, Johns Hopkins Medicine researchers have concluded that although two doses of a coronavirus vaccine confers some protection for people who have received solid organ transplants, it’s still not enough to enable them to dispense with masks, physical distancing and other safety measures.

 

This is a follow-up study to an earlier one published in March in JAMA, in which the researchers reported that only 17% of the participating transplant recipients produced sufficient antibodies after just one dose of a two-dose Covid-19 vaccine regimen.

 

“While there was an increase in those with detectable antibodies — 54% overall — after the second shot, the number of transplant recipients in our second study whose antibody levels reached high enough levels to ward off a SARS-CoV-2 infection was still well below what’s typically seen in people with healthy immune systems. Based on our findings, we recommend that transplant recipients and other immunocompromised patients continue to practice strict COVID-19 safety precautions, even after vaccination,” lead author Brian Boyarsky is quoted as saying on the Johns Hopkins website.

 

People who receive solid organ transplants (such as heart, lungs and kidneys) often must take drugs to suppress their immune systems and prevent rejection. Such regimens may interfere with a transplant recipient’s ability to make antibodies to foreign substances, including the protective ones produced in response to vaccines.

 

The new study evaluated this immunogenic response following the second dose of either the Moderna or Pfizer-BioNTech vaccine for 658 transplant recipients, none of whom had a prior diagnosis of Covid-19. The participants completed their two-dose regimen between December 16, 2020, and March 13, 2021.

 

In the most recent study, the researchers found that only 98 of the 658 study participants — 15% — had detectable antibodies to SARS-CoV-2 at 21 days after the first vaccine dose. This was comparable to the 17% reported in the March study.

 

At 29 days following the second dose, the number of participants with detectable antibodies rose to 357 out of 658 — 54%. After both vaccine doses were administered, 301 out of 658 participants — 46% — had no detectable antibody at all while 259 — 39% — only produced antibodies after the second shot.

 

The researchers also found that among the participants, the most likely to develop an antibody response were younger, did not take immunosuppressive regimens including anti-metabolite drugs and received the Moderna vaccine. These were similar to the associations seen in the single-dose study.— Source: Johns Hopkins Medicine.

https://indianexpress.com/article/explained/transplant-recipients-remain-vulnerable-to-covid-19-even-after-two-vaccine-doses-7308730/