Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Quidel (QDEL), a developer and manufacturer of diagnostic testing solutions for infectious diseases, gastrointestinal diseases, and women's health, advanced as much as 12% after the company announced after the bell yesterday that it had received FDA clearance for its AmpliVue Group B Strep Assay.

So what: According to Quidel's press release, the AmpliVue Group B Strep Assay will allow doctors and technicians in a hospital or laboratory setting to rapidly detect Group B streptococcus, or GBS, in antepartum women. The Centers for Disease Control and Prevention recommends a GBS test between weeks 35 and 37 of a pregnancy. The federal public health agency also estimates that 10%-30% of pregnant women carry GBS, according to Quidel's press release, 

Now what: With Quidel's rapid test immediately available for marketing, the upside reaction in shares seems fitting. Admittedly, Quidel isn't a particularly cheap stock here at 75 times next year's earnings, but the ease of use of its rapid molecular diagnostic tests and its growing portfolio of products is impressive. On the flip side, the Obamacare health insurance overhaul clouds the spending picture for numerous health providers over the near term and draws into question Medicare reimbursement rates in the future. So optimists may want to temper their expectations a bit in 2014.