WATERLOO â Two of Waterlooâs major health care systems expect to receive doses of the COVID-19 vaccine in coming days, according to hospital officials. Both UnityPoint Health-Allen Hospital and MercyOne Waterloo Medical Center officials said health care workers who are most exposed to COVID-19 will get the vaccine first. The Black Hawk County Health Department did not yet release the number of vaccine doses it will distribute to local health care systems. The U.S. Food and Drug Administration on Friday authorized emergency distribution of the first COVID-19 vaccine. The vaccine, which had 95% efficacy in clinical trials, is manufactured by pharmaceutical companies Pfizer and BioNTech. An advisory panel will vote Thursday on whether to recommend another COVID-19 vaccineâs approval by the FDA. The vaccine, also found to have about 95% efficacy in clinical trials, is manufactured by Moderna.