Public health funds differ primarily in the preventative care and discounts they offer clients. Before looking at these programs, it would be useful to know that you can change your insurer once every twelve months. The new coverage starts on the first day of each annual quarter: 1st January, 1st April, 1st July and 1st October. Upon changing, you are obliged to return your old health insurance card to the insurer and inform your GP and employer of the change.