Saturday, August 1, 2015

097 - An Experiment in Immunization Against Influenza with a Formaldehyde-Inactivated Virus

There had been some good results in animals with vaccines against influenza, and possibly some good trials in humans too, though not in others; influenza is tricky though, due to antigenic drift.

So this was another study, in Hungary during an epidemic in 1937. They used formaldehyde-inactivated virus taken from infected mouse lungs, and vaccinated 306 nurses and children in Budapest institutions with a single dose. 336 were controls.

They tested some subjects before and after the vaccination, and found that antibody levels rose a decent amount after the vaccination, 24x on average. One subject got tested before, after the vaccine, and then again after getting the flu, and the disease hadn't increased the levels any higher than the vaccine had (though obviously it wasn't a protective level somehow).

The epidemic was pretty small, so there were only 34 cases total in the study: 20 in the unvaccinated, and 14 in the vaccinated. This wasn't a significant difference, so it was negative.

But they isolated virus from some of the cases and found that it was a different serotype, so the vaccine might not've been good at targeting it anyway. Oh well.

Reference:
Taylor, R. M. & Dreguss, M. An Experiment in Immunization Against Influenza with a Formaldehyde-Inactivated Virus. Am. J. Epidemiol. 31-SectionB, 31–35 (1940).