To repeat his point - "learn to use a credible source of information" - citing sources such as local news and most blogs are not direct sources and generally considered unprofessional and amateur when dealing with things such as medical information. They are quite often not objective sources. Cite reputable sources, such as the CDC (the link he posted), medical journals (JAMA, NEJM, etc), actual studies, PubMed, etc. Dig in to where the source ACTUALLY pulls their information and cite that. The link you presented, a local news network, doesn't provide a reputable source, it just says "the director of the NIH says".
For example, here is a bad source.
Should I Get A Flu Shot? 5 Reasons Why Not.
While it does have citations, most are not reputable, and the article itself has an angle that it is trying to persuade you towards, nitpicking information that serves its agenda - it is not objective.