Pharmaceutical company AstraZeneca has acknowledged in U.K. court documents that its COVID-19 vaccine can cause a rare side effect, as first reported by The Telegraph. Dozens of victims have filed a class-action lawsuit claiming the vaccine caused death or serious injuries. AstraZeneca submitted legal documents to the High Court in the U.K., accepting that its COVID vaccine “can, in very rare cases, cause TTS.” TTS, or thrombocytopenia syndrome, causes the body to produce blood clots and a low blood platelet count. It can also be a side effect of taking certain medications, according to the Mayo Clinic. Fifty-one families are…