<p>An Israeli hospital administered fourth Covid-19 vaccine doses to a test group of health workers on Monday, in what it called the first major study into whether a second round of boosters will help contend with the fast-spreading Omicron variant.</p>.<p>Results of the trial, likely to be closely watched internationally, will be submitted to Israel's Health Ministry in about two weeks, said a spokesperson for Sheba Medical Centre near Tel Aviv.</p>.<p><strong>Also Read: <a href="https://www.deccanherald.com/international/world-news-politics/israel-trials-4th-dose-of-covid-19-vaccine-1065213.html" target="_blank">Israel trials 4th dose of Covid-19 vaccine</a></strong></p>.<p>Israel was the fastest country to roll out initial vaccinations a year ago, and became one of the first to launch a booster programme after observing that immunity waned over time.</p>.<p>On Monday, the Health Ministry said it was shortening the time between offering the second and third doses of Covid-19 vaccine to three months from five months in order to beat back rising infections as Omicron spreads.</p>.<p>Concerned about the risk of a sudden surge in hospitalizations, a ministry expert panel last week recommended Israel become the first country to offer a fourth jab to medical workers and those over 60 or with compromised immune systems.</p>.<p>The proposal was welcomed by the Israeli government, which has struggled against a plateauing of turn-out for vaccines. But the expert panel was divided over whether there is enough scientific data yet to justify fourth shots. Final approval by Health Ministry director-general Nachman Ash is still pending, and Israeli media say he may limit fourth shots to over 70s.</p>.<p>"The biggest question is, how significant is Omicron? It's clear to all that it is very contagious. But whether it causes very severe illness - that's the most significant question," said Gili Regev-Yochay, who is running the Sheba trial.</p>.<p>The Sheba study of 150 participants "will zero in on efficacy of the vaccine in producing antibodies, and safety, in order to ascertain if a fourth vaccine is needed in general", the hospital spokesperson said.</p>.<p>Hagai Levine, an epidemiologist, said more data is needed to gauge whether there has been a drop in protection against severe disease and death provided by the three shots offered so far.</p>.<p>"We can't blindly assume that another shot will solve it all, because it won't," said Levine, who heads Israel's Association of Public Health Physicians.</p>.<p>Some 63 per cent of Israel's 9.4 million population have received the first two vaccine doses, according to ministry data. Almost 45 per cent have taken a booster shot, they make up a little more than half those eligible for it. Close to 2,000 confirmed or suspected Omicron cases have been logged and infections have risen sharply over the past week.</p>.<p>Prime Minister Naftali Bennett has been in self-isolation at home since Sunday after his 14-year-old daughter tested positive for Covid-19, with what his office says is probably the Omicron variant. He subsequently tested negative, and his office said on Monday he would continue to work from home.</p>.<p><strong>Watch the latest DH Videos here:</strong></p>
<p>An Israeli hospital administered fourth Covid-19 vaccine doses to a test group of health workers on Monday, in what it called the first major study into whether a second round of boosters will help contend with the fast-spreading Omicron variant.</p>.<p>Results of the trial, likely to be closely watched internationally, will be submitted to Israel's Health Ministry in about two weeks, said a spokesperson for Sheba Medical Centre near Tel Aviv.</p>.<p><strong>Also Read: <a href="https://www.deccanherald.com/international/world-news-politics/israel-trials-4th-dose-of-covid-19-vaccine-1065213.html" target="_blank">Israel trials 4th dose of Covid-19 vaccine</a></strong></p>.<p>Israel was the fastest country to roll out initial vaccinations a year ago, and became one of the first to launch a booster programme after observing that immunity waned over time.</p>.<p>On Monday, the Health Ministry said it was shortening the time between offering the second and third doses of Covid-19 vaccine to three months from five months in order to beat back rising infections as Omicron spreads.</p>.<p>Concerned about the risk of a sudden surge in hospitalizations, a ministry expert panel last week recommended Israel become the first country to offer a fourth jab to medical workers and those over 60 or with compromised immune systems.</p>.<p>The proposal was welcomed by the Israeli government, which has struggled against a plateauing of turn-out for vaccines. But the expert panel was divided over whether there is enough scientific data yet to justify fourth shots. Final approval by Health Ministry director-general Nachman Ash is still pending, and Israeli media say he may limit fourth shots to over 70s.</p>.<p>"The biggest question is, how significant is Omicron? It's clear to all that it is very contagious. But whether it causes very severe illness - that's the most significant question," said Gili Regev-Yochay, who is running the Sheba trial.</p>.<p>The Sheba study of 150 participants "will zero in on efficacy of the vaccine in producing antibodies, and safety, in order to ascertain if a fourth vaccine is needed in general", the hospital spokesperson said.</p>.<p>Hagai Levine, an epidemiologist, said more data is needed to gauge whether there has been a drop in protection against severe disease and death provided by the three shots offered so far.</p>.<p>"We can't blindly assume that another shot will solve it all, because it won't," said Levine, who heads Israel's Association of Public Health Physicians.</p>.<p>Some 63 per cent of Israel's 9.4 million population have received the first two vaccine doses, according to ministry data. Almost 45 per cent have taken a booster shot, they make up a little more than half those eligible for it. Close to 2,000 confirmed or suspected Omicron cases have been logged and infections have risen sharply over the past week.</p>.<p>Prime Minister Naftali Bennett has been in self-isolation at home since Sunday after his 14-year-old daughter tested positive for Covid-19, with what his office says is probably the Omicron variant. He subsequently tested negative, and his office said on Monday he would continue to work from home.</p>.<p><strong>Watch the latest DH Videos here:</strong></p>