Intervet's Farm Animal Toxoplasmosis Vaccine Production Hits Snag

First, the basics -- farm animals tend to contract Toxoplasmosis from eating infected cat feces (ick!), and pigs fed garbage (yuk!) are more likely to contract it than those fed other diets. Even so, reports of transmission from contaminated feed hay and grass are common. So, it is a real problem on the farm.

Now, as we all know "manufacturing" a live vaccine is less like actual manufacturing -- and more like high-end baking -- like making a giant soufflé: sometimes it rises; sometimes it doesn't. In short, it is complicated -- will it be light and fluffy (good!), or a heavy, pasty, pancake (not so good)? Who knows, until we take it out?

That said, unlike a June Intervet equine West Nile virus vaccine recall, what is going on in Scotland right now is more akin to a case of the soufflé refusing to rise:

. . . .supply issues are linked to production problems, which are ‘not uncommon’ when manufacturing live vaccines [such as the "live" toxoplasmosis vaccine of legacy Schering-Plough/Intervet]. . . .

Still, when vaccine supply constraints exist, farmers must be careful not to begin a course of vaccinations, if they will be unable to complete the course due to stock-outages. The spectre of mutated, vaccine-resistant parasite evolution becomes a real possibility in these conditions. So while very small in terms of overall Merck revenue, this one bears watching -- and publicizing -- so as not to inadvertently create conditions ripe for mutated, vaccine-resistant farm to human parasite transmissions.

The parasite may be transmitted to humans (about one in ten in the U.S. are sero-positive for Toxoplasma) -- and that's why this matters to the general pharma readership, here. This is, at the moment, strictly a farmers' and vets' problem -- but worthy of monitoring. So I will. [Editor's Note: Thanks to the kind anonymous reader, commenting below, who allowed me to fix my errors, here.]