<div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>The cause of rare blood clots in a </span><a href="https://www.9news.com.au/covid-19" rel="" target="_blank" title="COVID-19"><span>COVID-19</span></a><span> </span><a href="https://www.9news.com.au/vaccine" rel="" target="_blank" title="vaccine"><span>vaccine</span></a><span> that killed eight people in </span><a href="https://www.9news.com.au/australia" rel="" target="_blank" title="Australia"><span>Australia</span></a><span> may have been found in a new study by local researchers.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>The AstraZeneca vaccine was one of the two primarily used in Australia during the early stages of the </span><a href="https://www.9news.com.au/coronavirus" rel="" target="_blank" title="pandemic"><span>pandemic</span></a><span>, but caused blood clots in about two to three people out of every 100,000 who received it.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>The condition was called vaccine-induced immune thrombocytopenia and thrombosis, 173 </span><a href="https://www.9news.com.au/national/covid-19-vaccine-actress-stroke-astra-zeneca-vaccination-melle-stewart-ben-lewis/ee270b36-142a-4772-8de8-44e84b062bbc" rel="" target="_blank" title="confirmed or probable cases"><span>confirmed or probable cases</span></a><span> of which caused by the vaccine were recorded.</span></div></div><div><div id="adspot-mobile-medium"></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><strong><span>READ MORE:</span></strong><span> </span><a href="https://www.9news.com.au/national/tradie-shortage-chippies-like-caitlyn-could-be-the-key-to-solving-our-housing-crisis/27a85e67-c1f6-43c0-80c7-5647e120f81e" rel="" target="_blank" title=""><strong><span>Chippies like Caitlyn could be the key to solving our housing crisis</span></strong></a><span></span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>A team of </span><a href="https://www.9news.com.au/research" rel="" target="_blank" title="researchers"><span>researchers</span></a><span> led by Australian </span><a href="https://www.9news.com.au/science" rel="" target="_blank" title="scientists"><span>scientists</span></a><span> at Flinders </span><a href="https://www.9news.com.au/university" rel="" target="_blank" title="University"><span>University</span></a><span> in </span><a href="https://www.9news.com.au/adelaide" rel="" target="_blank" title="Adelaide"><span>Adelaide</span></a><span> found that in some people, the immune system can confuse a normal adenovirus protein - something used in the AstraZeneca vaccine - for a human blood protein called platelet factor four (PF4).</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>Their study was released in the latest edition of the </span><em><span>New England Journal of Medicine</span></em><span>.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>The presence of PF4 causes the body to produce antibodies that trigger blood clotting, which can cause serious injury or death.</span></div></div><div><div class="OUTBRAIN" data-reactroot="" data-src="//www.9news.com.au/national/australia-covid-19-vaccine-astra-zeneca-blood-clot-cause/730c03ce-f908-4d0d-a7f8-781534429a85" data-widget-id="AR_5"></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>In many cases, the symptoms are minor and people are able to make a quick recovery with little impact on their lives.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><strong><span>READ MORE: </span></strong><a href="https://www.9news.com.au/national/angus-taylor-quits-sussan-ley-leadership-challenge-countdown-begins/ebf401ed-3a38-49b4-9cb3-38af38c8b8b7" rel="" target="_blank" title=""><strong><span>Liberal leadership spill confirmed ahead of urgent partyroom meeting</span></strong></a></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>Through linking the two, scientists believe they can now manufacture vaccines to avoid this rare symptom.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>"This was the missing link that explains how a normal immune response can, in very rare cases, become harmful," Dr Jing Jing Wang from Flinders University said.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>"By modifying or removing this specific adenovirus protein, future vaccines can avoid this extremely rare reaction while continuing to provide strong protection against disease."</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><strong><span>READ MORE: </span></strong><a href="https://www.9news.com.au/national/australia-first-home-buyer-loans/1fd19b39-e67f-42c2-b7d6-791c3e91e614" rel="" target="_blank" title=""><strong><span>One state driving the biggest spike in first home buyer loans in years</span></strong></a></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>Symptoms of thrombosis included severe headache, blurred vision or shortness of breath, with these occurring from four to 42 days after receiving the first dose of the vaccine.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>To minimise the risk of the rare side-effect, the Australian </span><a href="https://www.9news.com.au/government" rel="" target="_blank" title="government"><span>government</span></a><span> recommended the AstraZeneca vaccine only be given to people over 60 years old.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>This is because younger people have a higher risk of producing a stronger antibody response and developing severe blood clots.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>Despite this, many people below 60-years-old received at least one dose of the AstraZeneca vaccine due to shortages of the Pfizer vaccine and a desire to reach vaccination targets nationwide.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>The vaccine hasn't been available in Australia since 2023.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><em><strong><span>NEVER MISS A STORY: Get your breaking news and exclusive stories first by following us across all platforms.</span></strong></em></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><ul><li><p><em><strong><span>Download the 9NEWS App here via</span></strong></em><span> </span><a href="https://apps.apple.com/au/app/9news/id1010533727"><em><strong><span>Apple</span></strong></em></a><span> </span><em><strong><span>and</span></strong></em><span> </span><a href="https://play.google.com/store/apps/details?id=nineNewsAlerts.nine.com&amp;hl=en_AU&amp;pli=1"><em><strong><span>Google Play</span></strong></em></a></p></li><li><p><em><strong><span>Make 9News your preferred source on Google by</span></strong></em><span> </span><a href="https://9.nine.com.au/8x987w"><em><strong><span>ticking this box here</span></strong></em></a></p></li><li><p><em><strong><span>Sign up to</span></strong></em><span> </span><a href="https://login.nine.com.au/edm?client_id=nineatnine"><em><strong><span>our breaking newsletter here</span></strong></em></a></p></li></ul></div></div>