Bit of scaremongering there, Spice :-( It was Facebook which widely circulated the false claim of the flu vaccine lowering peoples resistance to Covid 19. According to most sites, it does not. A study done by the American military back in October 2019 into Coronavirus (not C19) and the data used was from the 2017-18 flu season. For the avoidance of doubt, there is no evidence that a flu jab increases the risk of contracting Covid 19. The guidance from the US Centers For Disease Control is clear, "Influenza vaccination does not make people more susceptible to other respiratory infections."