Looks like that one-time boost from sales of swine flu vaccine may not add much to the bottom lines of vaccine makers like GlaxoSmithKline (NYSE:GSK), AstraZeneca, sanofi-aventis (NYSE:SNY), and Novartis (NYSE:NVS). The governments that bought the vaccines may not need as much as expected.

Germany is trying to renegotiate its contract so that it will have to buy less of the H1N1 vaccine, while Spain is trying to return what it doesn't need. After a slow start, the U.S. has plenty of vaccine to go around. With the flu season hitting earlier than normal in the U.S., one has to wonder if the U.S. might be getting in line for post-holiday returns.

Technically the swine flu was a pandemic, but it doesn't seem to be reaching anywhere near the level of the Spanish Flu. The pandemic-that-wasn't has cratered many speculative plays where investors were hoping for adoption of technology that's relatively unproven compared to standard flu vaccines or antivirals like Roche's and Gilead Sciences' (NASDAQ:GILD) Tamiflu.

Company

Price (Decrease) From
52-Week High

BioCryst Pharmaceuticals (NASDAQ:BCRX)

(54.3%)

Novavax (NASDAQ:NVAX)

(65.7%)

Sinovac Biotech (NASDAQ:SVA)

(49.8%)

Source: Yahoo! Finance.

As I warned in the past, investors have to be careful in speculating whether a virus will mutate enough to become a serious threat. Will a serious pandemic happen? Yes, eventually, and that might make companies like BioCryst a lot of money. But don't get caught up in the media hoopla. The swine flu seems headed to the same nest where the avian flu retired.

Here's another speculative investment that Brian Richards and Tim Hanson say you should avoid.

Novartis is a Motley Fool Global Gains selection. Investing internationally doesn't have to be scary, and it can certainly be profitable. Click here to grab a 30-day trial subscription to the newsletter where you'll see all of our current picks for a global economy.

Shot-hating Fool contributor Brian Orelli, Ph.D., lucked out and got the nasal-spray swine flu vaccine instead. He doesn't own shares of any company mentioned in this article. The Fool's disclosure policy thinks Brian is a wimp.