The affected shows were to take place in Seinajoki, Finland; Berlin, Germany; Clisson, France; Dessel, Belgium; Vienna Austria; and Saint Gallen, Switzerland.

Davis was admitted to a London-area hospital June 9 and did not perform at the June 10 U.K. Download Festival. The rest of the band played an abbreviated set with help of several guest vocalists. Corey Taylor from Slipknot/Stone Sour, Dez Fafara from Devildriver, Jesse Hasek from 10 Years, Benji Webbe from Skindred, M. Shadows from Avenged Sevenfold and Matt Heafy from Trivium all took a turn at the mic.

Davis has reportedly been diagnosed with a blood disorder called immune thrombocytopenic purpura which causes a low blood-platelet count, preventing blood from clotting.

“I started getting these weird bruises all over my body about two weeks ago,” Davis wrote on the band’s Web site.

“I was getting very weak after the shows so I saw a doctor in London Friday. He took some blood tests and when the results came in, they rushed me to the hospital. It turned out that I have ITP … a blood infection where, because of an allergic reaction I had to some medication, my blood platelets were really low. If I continued to headbang onstage, I could have had a brain hemorrhage and dropped dead on the spot.”

Doctors have now ordered his to take the next few weeks off to rest. The band plans to return Europe as its schedule permits.

Korn is still expected to headline the The 30-city festival trek through North America will launch July 27 in Virginia Beach and will feature Korn, Deftones, Stone Sour, Flyleaf and Dir en grey on the main stage.