(KRON/CNN) — Researchers are seeing a mysterious rise in cases of scarlet fever across England and East Asia.

Scarlet fever is a bacterial disease that usually impacts children. It causes a bright red rash on most of the body.

Some people can develop strep throat. The disease has been rising for several years in the UK.

It hit a 50-year-high last year with 20,000 cases reported.

Researchers say they don’t know what’s causing the outbreak and are urging doctors around the world to watch out for symptoms and new cases.

Full report: http://www.cnn.com/2017/11/27/health/scarlet-fever-mystery-study/index.htmlWHAT OTHERS ARE CLICKING ON: 

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