Viruses seem to be all the rage these days. If we're not worried about militant wackos weaponizing smallpox, then we're worried about the poultry of the world striking back at us with bird flu for all of those buckets of fried chicken we've eaten. What this all means is that vaccines, once a sort of sleepy but cash-rich business, are now getting a lot more attention.

That attention has certainly extended to Crucell (NASDAQ:CRXL), a Dutch company possibly positioned as a major future player in the development of vaccines and antibodies for infectious diseases. Although the stock is up more than 200% over the past year, the story may only be getting started for investors.

The company did report financial results on Monday, but I won't spend too much time on them. After all, we're talking about a development-stage biotech company here. So while I appreciate that revenue was higher and the loss was lower, all I really care about with quarter-to-quarter financials is the cash burn rate and the cash on the balance sheet. Speaking of the former, the company seems to be burning about $9 million per quarter, with more than $134 million in the kitty. That's very promising.

One of the strengths of this company is its partnerships. Leading companies such as Chiron (NASDAQ:CHIR), Sanofi-Aventis (NYSE:SNY), Merck (NYSE:MRK), and GlaxoSmithKline (NYSE:GSK) all work with Crucell, and that's just an abbreviated list. What are they working on? Vaccines and antibodies for infectious diseases like influenza, West Nile virus, Ebola, malaria, rabies, tuberculosis, and hepatitis C -- conditions that could generate billions of dollars' worth of vaccine sales.

Better still, Crucell has positioned itself as more of a guide than an explorer. The company has developed separate technologies to produce human cell lines, design better adenoviral vectors, and explore disease-associated molecules more effectively -- and larger pharmaceutical companies are paying for access to that technology. It would seem that these partners really do value it. Sanofi elected to pay a milestone fee to Crucell even though the underlying trial was actually delayed a bit. When you can get a giant to pay up sooner than they might technically have to, that's making a statement.

Crucell is a frustratingly difficult stock to value. Most projects are at early stages, and many of them have uncertain revenue streams -- from which Crucell will get only small cuts. For instance, I have no doubt that an Ebola or malaria vaccine will be a major advancement for world health, but I don't know how much money there is out there to pay for one since those diseases primarily afflict poorer countries. It doesn't seem terribly overpriced relative to the likes of Motley Fool Rule Breakers recommendations Protein Design Labs (NASDAQ:PDLI) and Vertex (NASDAQ:VRTX), but the hype and uncertainty have me a bit concerned -- at least until I can hammer out a valuation model that satisfies me.

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Fool contributor Stephen Simpson owns shares of Sanofi-Aventis.