<div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>A fourth case of potentially deadly Legionnaires' </span><a href="https://www.9news.com.au/disease" rel="" target="_blank" title="disease"><span>disease</span></a><span> has been reported in Sydney.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>A fresh alert has been issued by authorities after an increase in the number of people diagnosed earlier this week.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>All four people in the cluster, including three cases confirmed yesterday, spent time in Clarence Street near Wynyard in the CBD between December 9 and December 18.</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><a href="https://www.9news.com.au/national/brisbane-bins-acacia-ridge-claims-his-yellow-bin-missed-for-14-weeks/6b9f215b-6353-497e-b6ff-5947bd0652d7" rel="" target="_blank" title=""><strong><span>'Driving me mad': Man claims recycling bin not emptied for months</span></strong></a><strong></strong></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>Legionnaires' disease develops when Legionella bacteria gets into sources such as cooling towers on top of large buildings.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>"People are exposed if contaminated water particles from a cooling system are in the air and then breathed in," Dr Vicky Sheppeard said.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>"Symptoms can develop up to 10 days after exposure and include fever, chills, a cough and shortness of breath, and may lead to severe chest infections such as pneumonia.</span></div></div><div><div class="OUTBRAIN" data-reactroot="" data-src="//www.9news.com.au/national/legionnaires-disease-outbreak-sydney-cbd-clarence-street-wynyard-nsw/9e906b0f-91c5-407e-93df-e67ea1367670" data-widget-id="AR_5"></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/bondi-beach-terror-attack-new-support-hub-for-community-opens/3489b3a2-71dd-408e-8e62-98fcf6157742" rel="" target="_blank" title=""><strong><span>'Hundreds' expected to descend on new Bondi support hub</span></strong></a><strong></strong></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>"Those most at risk include elderly people, people with underlying lung or other serious health conditions, and smokers."</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>All four people are in hospital, Sheppard said.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>She added the source of the current outbreak is being investigated, with building managers in the CBD urged to check their cooling towers.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><a href="https://www.9news.com.au/new-south-wales" rel="" target="_blank" title="NSW"><span>NSW</span></a><span> Health said anyone who had been in the Clarence Street and Wynyard areas since December 9 should monitor for symptoms.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><span>Infected people can develop symptoms between two and 10 days of initially contracting the disease.</span></div></div><div class="block-content"><div class="styles__Container-sc-1ylecsg-0 goULFa"><a href="https://www.9news.com.au/national/how-to-follow-9news-digital/29855bb1-ad3d-4c38-bc25-3cb52af1216f"><em><strong><span>DOWNLOAD THE 9NEWS APP</span></strong></em></a><em><strong><span>: Stay across all the latest in breaking news, sport, politics and the weather via our news app and get notifications sent straight to your smartphone. Available on the</span></strong></em><span> </span><a href="https://apps.apple.com/au/app/9news/id1010533727"><em><strong><span>Apple App Store</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><em><strong><span>.</span></strong></em></div></div>