<p>The levels of IgG antibodies against SARS-CoV-2 remain stable, or even increase, seven months after infection, according to a study of healthcare workers published in the journal Nature Communications on Friday.</p>.<p>The researchers from the Barcelona Institute for Global Health (ISGlobal) in Spain also suggest that pre-existing antibodies against common cold coronaviruses could protect from Covid-19.</p>.<p>They noted that in order to predict the pandemic's evolution and develop effective strategies, it is critical to better understand the dynamics and duration of immunity to SARS-CoV-2.</p>.<p><a href="http://www.deccanherald.com/tag/covid-19"><strong>SPECIAL CORONAVIRUS COVERAGE ONLY ON DH</strong></a></p>.<p>The researchers followed a group of healthcare workers from the beginning of the pandemic in order to evaluate the levels of antibodies against different SARS-CoV-2 antigens over time.</p>.<p>"This is the first study that evaluates antibodies to such a large panel of SARS-CoV-2 antibodies over 7 months," said ISGlobal researcher Carlota Dobano, who led the study.</p>.<p>The team analysed blood samples from 578 participants, taken at four different timepoints between March and October 2020.</p>.<p>They measured the level and type of IgA, IgM or IgG antibodies to six different SARS-CoV-2 antigens as well as the presence of antibodies against the four coronaviruses that cause common colds in humans.</p>.<p>The researchers also analysed the neutralising activity of antibodies in collaboration with researchers at the University of Barcelona.</p>.<p>The results show that the majority of infections among healthcare workers occurred during the first pandemic wave.</p>.<p>With the exception of IgM and IgG antibodies against the nucleocapsid (N), the rest of IgG antibodies remained stable over time, confirming results from other recent studies.</p>.<p>Immunoglobulin G (IgG), the most abundant type of antibody, is found in all body fluids. These antibodies are produced in the later stages of an infection and see the body through recovery.</p>.<p><strong>Also Read | <a href="https://www.deccanherald.com/international/cansinobio-says-booster-shot-can-reverse-drop-in-covid-19-antibodies-1016780.html" target="_blank">CanSinoBIO says booster shot can reverse drop in Covid-19 antibodies</a></strong></p>.<p>"Rather surprisingly, we even saw an increase of IgG anti-spike antibodies in 75 per cent of the participants from month five onwards, without any evidence of re-exposure to the virus," said Gemma Moncunill, senior co-author of the study.</p>.<p>No reinfections were observed in the cohort, the researchers said.</p>.<p>The study also suggests that the antibodies against human cold coronaviruses (HCoV) could confer cross-protection against Covid-19 infection.</p>.<p>People who were infected by SARS-CoV-2 had lower levels of HCoV antibodies, according to the researchers. Also, asymptomatic individuals had higher levels of anti-HCoV IgG and IgA than those with symptomatic infections, they said.</p>.<p>"Although cross-protection by pre-existing immunity to common cold coronaviruses remains to be confirmed, this could help explain the big differences in susceptibility to the disease within the population,” Dobano added. </p>
<p>The levels of IgG antibodies against SARS-CoV-2 remain stable, or even increase, seven months after infection, according to a study of healthcare workers published in the journal Nature Communications on Friday.</p>.<p>The researchers from the Barcelona Institute for Global Health (ISGlobal) in Spain also suggest that pre-existing antibodies against common cold coronaviruses could protect from Covid-19.</p>.<p>They noted that in order to predict the pandemic's evolution and develop effective strategies, it is critical to better understand the dynamics and duration of immunity to SARS-CoV-2.</p>.<p><a href="http://www.deccanherald.com/tag/covid-19"><strong>SPECIAL CORONAVIRUS COVERAGE ONLY ON DH</strong></a></p>.<p>The researchers followed a group of healthcare workers from the beginning of the pandemic in order to evaluate the levels of antibodies against different SARS-CoV-2 antigens over time.</p>.<p>"This is the first study that evaluates antibodies to such a large panel of SARS-CoV-2 antibodies over 7 months," said ISGlobal researcher Carlota Dobano, who led the study.</p>.<p>The team analysed blood samples from 578 participants, taken at four different timepoints between March and October 2020.</p>.<p>They measured the level and type of IgA, IgM or IgG antibodies to six different SARS-CoV-2 antigens as well as the presence of antibodies against the four coronaviruses that cause common colds in humans.</p>.<p>The researchers also analysed the neutralising activity of antibodies in collaboration with researchers at the University of Barcelona.</p>.<p>The results show that the majority of infections among healthcare workers occurred during the first pandemic wave.</p>.<p>With the exception of IgM and IgG antibodies against the nucleocapsid (N), the rest of IgG antibodies remained stable over time, confirming results from other recent studies.</p>.<p>Immunoglobulin G (IgG), the most abundant type of antibody, is found in all body fluids. These antibodies are produced in the later stages of an infection and see the body through recovery.</p>.<p><strong>Also Read | <a href="https://www.deccanherald.com/international/cansinobio-says-booster-shot-can-reverse-drop-in-covid-19-antibodies-1016780.html" target="_blank">CanSinoBIO says booster shot can reverse drop in Covid-19 antibodies</a></strong></p>.<p>"Rather surprisingly, we even saw an increase of IgG anti-spike antibodies in 75 per cent of the participants from month five onwards, without any evidence of re-exposure to the virus," said Gemma Moncunill, senior co-author of the study.</p>.<p>No reinfections were observed in the cohort, the researchers said.</p>.<p>The study also suggests that the antibodies against human cold coronaviruses (HCoV) could confer cross-protection against Covid-19 infection.</p>.<p>People who were infected by SARS-CoV-2 had lower levels of HCoV antibodies, according to the researchers. Also, asymptomatic individuals had higher levels of anti-HCoV IgG and IgA than those with symptomatic infections, they said.</p>.<p>"Although cross-protection by pre-existing immunity to common cold coronaviruses remains to be confirmed, this could help explain the big differences in susceptibility to the disease within the population,” Dobano added. </p>