BERLIN (Reuters) - Germany’s COVID-19 vaccination campaign has been overshadowed by a mishap in the north where eight workers in an elderly care home received an overdose. Vorpommern-Ruegen district authorities said the workers in Stralsund city received five times the recommended dose of the BioNTech-Pfizer vaccine on Sunday. Four went to hospital for observation after developing flu-like symptoms. “I deeply regret the incident. This individual case is due to individual errors. I hope that all those affected do not experience any serious side-effects,” district chief Stefan Kerth said in a statement. The incident came after some German districts declined to use vaccines received over the weekend on suspicion that cold conditions were interrupted during delivery. Vorpommern-Ruegen authorities pointed to previous statements by BioNtech saying larger doses were tested in the Phase 1 study without serious consequences. There was no immediate comment from the pharmaceutical companies.