Full Coverage
Polio is found in the U.K. for the first time in nearly 40 years. Here's what it means
By Michaeleen Doucleff
Polio virus detected in London sewage samples
By Philippa Roxby & Jim Reed
Poliovirus in London sewage – what you need to know
By Zania Stamataki
After Poliovirus Is Found in London, U.K. Declares Emergency
By Apoorva Mandavilli & Euan Ward