<p>According to a new study, although over time the number of SARS-CoV-2 antibodies fall in both previously infected and vaccinated patients, the performance of antibodies improve only after the previous infection.</p>.<p>The researchers, including Carmit Cohen of the Sheba Medical Center, indicated that while protection against re-infection lasts for a long time in SARS-CoV-2 recovered patients, breakthrough infections are increasingly common six months after vaccination.</p>.<p>"While the number of antibodies decrease with time in both Covid-19 recovered (but never vaccinated) patients and vaccinated (but never infected) individuals, the quality of antibodies increases the following infection but not after vaccination," the researchers said.</p>.<p>The study also found that, contrary to expectations, previously infected patients with obesity had a higher and more sustained immune response than overweight and normal weight range patients.</p>.<p>For the study, to be presented at this year's European Congress of Clinical Microbiology and Infectious Diseases, the team analysed the humoral (antibody-induced) immune response in Covid-19 recovered but unvaccinated individuals for up to a year and compared it with those who had received two doses of the Pfizer vaccine (but no previous infection) over eight months.</p>.<p>The study recruited previously infected-unvaccinated and double vaccinated never infected individuals from March 25 to November 25 2020 and closed in April 2021, just before the Delta variant arrived in Israel.</p>.<p>The researchers followed up on 130 patients diagnosed with SARS-COV-2 using PCR testing. These patients had not been vaccinated and remained unvaccinated during the study. None of these patients were reinfected during the study period.</p>.<p><strong>Watch the latest DH Videos here:</strong></p>
<p>According to a new study, although over time the number of SARS-CoV-2 antibodies fall in both previously infected and vaccinated patients, the performance of antibodies improve only after the previous infection.</p>.<p>The researchers, including Carmit Cohen of the Sheba Medical Center, indicated that while protection against re-infection lasts for a long time in SARS-CoV-2 recovered patients, breakthrough infections are increasingly common six months after vaccination.</p>.<p>"While the number of antibodies decrease with time in both Covid-19 recovered (but never vaccinated) patients and vaccinated (but never infected) individuals, the quality of antibodies increases the following infection but not after vaccination," the researchers said.</p>.<p>The study also found that, contrary to expectations, previously infected patients with obesity had a higher and more sustained immune response than overweight and normal weight range patients.</p>.<p>For the study, to be presented at this year's European Congress of Clinical Microbiology and Infectious Diseases, the team analysed the humoral (antibody-induced) immune response in Covid-19 recovered but unvaccinated individuals for up to a year and compared it with those who had received two doses of the Pfizer vaccine (but no previous infection) over eight months.</p>.<p>The study recruited previously infected-unvaccinated and double vaccinated never infected individuals from March 25 to November 25 2020 and closed in April 2021, just before the Delta variant arrived in Israel.</p>.<p>The researchers followed up on 130 patients diagnosed with SARS-COV-2 using PCR testing. These patients had not been vaccinated and remained unvaccinated during the study. None of these patients were reinfected during the study period.</p>.<p><strong>Watch the latest DH Videos here:</strong></p>