Note the claims.
" about 400 heads of small cattle were vaccinated"
" smallpox is a particularly dangerous virus disease of mammals and birds"
From these claims we can infer that the threat is not the smallpox virus because the smallpox does not have an animal vector. If it did then eradication via vaccination would not have worked. Smallpox only naturally infects humans and does not exist in a carrier state.
If this headline were true not only would there have been 400 small cattle vaccinated but also the WHO would have reported a world wide threat. And the price of SIGA stock would have shot up an order of magnitude within minutes of that report.
The most likely explanation is that the original story which was not written in English was mistranslated as to the virus at issue.
On Jan. 9 at 2:50 p.m. ET, 25,000 of the January 2015 50-strike puts in Herbalife were bought for $7.25 each; at about the same time on Jan. 10, 20,000 more were purchased for slightly less.
Buying a put option is profitable only if the stock price falls below the strike price of the put minus the money spent. In total, this trade costs over $32 million and represents a bet that Herbalife stock will fall below 42.75 by January 2015—a 50 percent decline from where the stock was trading.