There's no question that Ebola is a frightening disease that requires significant attention, but investors should be careful about how much of their portfolio they invest in companies pursuing Ebola therapies. After all, Ebola is an uncommon disease, and outbreaks of the disease are unpredictable. For that reason, investors might want to consider investing in these three healthcare themes instead.

Dan Caplinger: The Ebola epidemic deserves all the attention it's getting, but for investors, there are more certain trends that are more likely to produce reliable profits for years to come. One such area is in the transformation of medical recordkeeping to promote electronic health records. Health information management companies are positioning themselves to handle the vast transition of millions of patients' medical records to improve portability and facilitate the flow of vital information across different healthcare providers.

Competition in the healthcare IT industry has been fierce, with players such as Quality Systems (NASDAQ:NXGN) and Allscripts (NASDAQ:MDRX) fighting against privately held Epic Systems for market share in the rapidly growing marketplace. The most successful players in the space have realized that once they establish a core group of customers using their systems, it's easier to earn recurring revenue from maintenance contracts and other ongoing income sources, taking advantage of the hassles involved in switching from one system to another. Although investors disagree on which companies are most likely to outperform their peers, one thing is clear: Moving medical records into an easily accessible digital format is inevitable, and the companies that prove to be the best at helping transform the health care industry's recordkeeping practices will make their shareholders a lot wealthier.

Cheryl Swanson: Ebola seems to be on the wane, but there's another public health crisis for which the prognosis is bad and getting worse: obesity. Weight-related medical issues add a jaw-dropping $190 billion a year to America's medical costs.

Thus far, anti-obesity drugs haven't fulfilled their promise. Hindered by insurers that wouldn't cover the drug and doctors who were skeptical about their value, anti-obesity drugmakers Vivus Pharmaceuticals (NASDAQ:VVUS) and Arena Pharmaceuticals (NASDAQ:ARNA) never gained traction. Vivus' stock plummeted more than 60% last year, while Arena lost 30%.

Orexigen Therapeutics (NASDAQ: OREX) is the one I like in this space. Its diet pill Contrave fought through years of frustration to gain the FDA blessing, but Orexigen learned something from the delay. If cost was a barrier for Vivus and Arena, Orexigen's strategy has been to come in with very aggressive price points for Contrave, around $60 a month.

Last month, Danish drugmaker Novo Nordisk (NYSE:NVO) also got the FDA nod for its weight-loss med, Saxenda. The company has clearly said it expects at least $1 billion in annual sales, but it isn't nearly so clear on how it intends to achieve that goal. In contrast with Orexigen, whose marketing partner Takeda Pharmaceuticals is putting 900 reps on the street to sell Contrive, Novo plans on 500 reps, while Arena will field 450, and Vivus a measly 150.

The obesity market is quirky, but it's much too early to give up on these drugs. The Affordable Care Act requires insurers to tackle obesity as part of preventive services. While coverage of new solutions is still a work in progress, with medical costs soaring for weight-related problems, it seems likely these drugs will eventually be covered for at least high-risk obesity patients.

Brian Orelli: The problem with investing in a disease like Ebola is that it's a one-and-done type of treatment. Drugs that treat the disease will be used on patients only until they're rid of the virus. There's a potential for a larger number of people to be vaccinated, if a company can successfully develop a vaccine, but even that's only a-couple-and-done scenario, assuming there are booster shots involved.

A disease like cystic fibrosis, on the other hand, has to be treated for life, making it easier for the companies with drugs to treat the disease to build sales. And one thing about cystic fibrosis is that there's only one company, Vertex Pharmaceuticals (NASDAQ:VRTX), limiting competition for now. There are some antibiotics approved to treat cystic fibrosis symptoms, but Vertex is the only company with a drug treating the underlying condition.

Vertex's Kalydeco is already on the market but is suitable for only a small subset of patients with cystic fibrosis, which is caused by different mutations in a gene called cystic fibrosis transmembrane conductance regulator, or CFTR. Fortunately for investors and patients alike, Vertex has a new combination drug that contains Kalydeco and a new drug, lumacafator. About half of cystic fibrosis patients have the F508del CFTR mutation that can be treated with the new combination.

The biotech has already submitted the combination product to the FDA, and we should hear by July 5, perhaps earlier, whether the drug is approved. Given the unmet need and the clinical benefit seen in the phase 3 trials, most people are expecting an approval. An EU approval decision should come later in the year.

Beyond F508del CFTR mutation, Vertex is trying to treat patients with other mutations using other combinations that are in clinical testing.

Editor's Note: The spelling of Saxenda has been corrected.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.