<p>A Russian trial testing the effectiveness of revaccination with the Sputnik V shot to protect against new mutations of the coronavirus is producing strong results, researchers said on Saturday.</p>.<p>Last month President Vladimir Putin ordered a review by March 15 of Russian-produced vaccines for their effectiveness against new variants spreading in different parts of the world.</p>.<p>"(A) recent study carried out by the Gamaleya Centre in Russia showed that revaccination with Sputnik V vaccine is working very well against new coronavirus mutations, including the UK and South African strains of coronavirus," said Denis Logunov, a deputy director of the centre, which developed the Sputnik V shot.</p>.<p>Results of the trial are expected to be published soon, but this was the first indication of how the tests are going. No further details were available yet.</p>.<p><strong>Read | <a href="https://www.deccanherald.com/international/egypt-registers-russias-sputnik-v-covid-19-vaccine-954891.html" target="_blank">Egypt registers Russia's Sputnik V Covid-19 vaccine</a></strong></p>.<p>So-called viral vector shots - such as Sputnik V and a shot developed by AstraZeneca - use harmless modified viruses as vehicles, or vectors, to carry genetic information that helps the body build immunity against future infections.</p>.<p>The revaccination used the same Sputnik V shot, based upon the same adenovirus vectors. The trial indicated this did not impact effectiveness, Logunov said in a statement to <em>Reuters</em>.</p>.<p>Some scientists have raised the possible risk that the body also develops immunity to the vector itself, recognising it as an intruder and trying to destroy it.</p>.<p>But developers of Sputnik V disagreed this would pose long-term problems.</p>.<p><strong>Also Read | <a href="https://www.deccanherald.com/national/what-sputnik-vs-emergency-approval-may-mean-for-india-952629.html" target="_blank">What Sputnik V's emergency approval may mean for India</a></strong></p>.<p>"We believe that vector-based vaccines are actually better for future revaccinations than vaccines based on other platforms," Logunov said.</p>.<p>He said that the researchers found that antibodies specific to the vectors used by the shot - which could generate an anti-vector reaction and undermine the work of the shot itself - waned "as early as 56 days after vaccination".</p>.<p>This conclusion was based on a trial of a vaccine against Ebola developed earlier by the Gamaleya Institute using the same approach as for the Sputnik V shot.</p>.<p>Vector immunity is not a new issue but has come under renewed scrutiny as companies including Johnson & Johnson anticipate regular Covid-19 vaccinations, like annual influenza shots, may be needed to combat new variants of the coronavirus.</p>
<p>A Russian trial testing the effectiveness of revaccination with the Sputnik V shot to protect against new mutations of the coronavirus is producing strong results, researchers said on Saturday.</p>.<p>Last month President Vladimir Putin ordered a review by March 15 of Russian-produced vaccines for their effectiveness against new variants spreading in different parts of the world.</p>.<p>"(A) recent study carried out by the Gamaleya Centre in Russia showed that revaccination with Sputnik V vaccine is working very well against new coronavirus mutations, including the UK and South African strains of coronavirus," said Denis Logunov, a deputy director of the centre, which developed the Sputnik V shot.</p>.<p>Results of the trial are expected to be published soon, but this was the first indication of how the tests are going. No further details were available yet.</p>.<p><strong>Read | <a href="https://www.deccanherald.com/international/egypt-registers-russias-sputnik-v-covid-19-vaccine-954891.html" target="_blank">Egypt registers Russia's Sputnik V Covid-19 vaccine</a></strong></p>.<p>So-called viral vector shots - such as Sputnik V and a shot developed by AstraZeneca - use harmless modified viruses as vehicles, or vectors, to carry genetic information that helps the body build immunity against future infections.</p>.<p>The revaccination used the same Sputnik V shot, based upon the same adenovirus vectors. The trial indicated this did not impact effectiveness, Logunov said in a statement to <em>Reuters</em>.</p>.<p>Some scientists have raised the possible risk that the body also develops immunity to the vector itself, recognising it as an intruder and trying to destroy it.</p>.<p>But developers of Sputnik V disagreed this would pose long-term problems.</p>.<p><strong>Also Read | <a href="https://www.deccanherald.com/national/what-sputnik-vs-emergency-approval-may-mean-for-india-952629.html" target="_blank">What Sputnik V's emergency approval may mean for India</a></strong></p>.<p>"We believe that vector-based vaccines are actually better for future revaccinations than vaccines based on other platforms," Logunov said.</p>.<p>He said that the researchers found that antibodies specific to the vectors used by the shot - which could generate an anti-vector reaction and undermine the work of the shot itself - waned "as early as 56 days after vaccination".</p>.<p>This conclusion was based on a trial of a vaccine against Ebola developed earlier by the Gamaleya Institute using the same approach as for the Sputnik V shot.</p>.<p>Vector immunity is not a new issue but has come under renewed scrutiny as companies including Johnson & Johnson anticipate regular Covid-19 vaccinations, like annual influenza shots, may be needed to combat new variants of the coronavirus.</p>