THE TROU­BLE WITH EQUINE TITERS

EQUUS - - Eq Tack& Gear -

When dis­cussing vac­ci­na­tion op­tions with horse own­ers, I am of­ten asked, “Why can’t we just pull a titer?” When talk­ing about im­mu­niza­tion, “titer” refers to the amount of an­ti­bod­ies to a par­tic­u­lar dis­ease that can be found in the blood. In the­ory, a body with a high titer against a dis­ease is prop­erly pre­pared to fight it and an an­nual booster isn’t nec­es­sary. In peo­ple this may be true, but in horses it is not. In other words, even a horse with a “high titer” against the pathogens that cause a par­tic­u­lar dis­ease may not

ac­tu­ally be equipped to fight them off.

We can pull blood from a horse and get an­ti­body num­bers for nearly any dis­ease but, with one ex­cep­tion, we don’t know what the num­bers ac­tu­ally mean. Strep­to­coc­cus equi, the bac­terium that causes stran­gles, is the only titer for which we have re­li­able, in­ter­pretable sci­ence. You could, tech­ni­cally, pull a titer each year for stran­gles to make vac­ci­na­tion de­ci­sions, and some ve­teri­nar­i­ans do: The data needed to in­ter­pret

the re­sults is avail­able in the Amer­i­can Col­lege of Vet­eri­nary In­ter­nal Medicine’s con­sen­sus state­ment on S. equi. That said, there are other con­sid­er­a­tions to weigh re­gard­ing the stran­gles vac­cine, such as ef­fi­cacy and risks of side ef­fects, so the titer is just one fac­tor to con­sider.

For any other dis­ease, how­ever, it’s ir­re­spon­si­ble to base vac­ci­na­tion de­ci­sions on titers. We sim­ply do not have the sci­en­tific data needed to cor­rectly in­ter­pret the re­sults. --- Melinda Freck­le­ton, DVM

Newspapers in English

Newspapers from USA

© PressReader. All rights reserved.