If people in your raid use WeakAuras you can use my WeakAura: it tracks people with Life Drain and announces in /say the number of stacks they currently have. To load it go to WeakAuras > New > Import and copy the text below, feel free to move the icon wherever you like:
Code:
dOdzcaGErvAxsvEnczMQK5kkZgvDtePBlspMI2Pi2lz3a7xs(jcmmk8BbhwvdvurdwsnCj6qsv1FfQJHeptc1cfvQLkHSyPQSCuEOqspfAziINdAIQutvftMstxXfLaxfjvxMQRlv2OOsMgc1MLY2fsClrv9vHu(ms9De0iLGojQy0iQXJKYLes1zfvXPv68OshuighsY3evyrrhHRqoGXzT30Z4ygaWmS055JrYVnqy8128B2VadsecfsPhX9YrpQeMk0k0QJWwam4MxxjKqSq7cl5FU48Mebfg9sHuJGwd6JsYVyddH8H3QJqwG31ryAh)S6OrJgHmNEdGd3sx4AgacFZzdaOocHZZgDeM6q4t7cV2MxvFZ(fuvhav1PE)cTHyyOdyvFctDi8P94HBPleJKhH2qCQdHpTRCleg6awHCaJZAVPNfXAjaaZIM)efPJ9WmsD7(zyOdyHzrwwHbgOxAzXcHHoGn2K8daoVqsF44mnAec6spSLM2zqLqr4BT7SbWZhpSLM2zqD0iCylnTZ0ri4tDOokHIWRT5v13SFbAeA9(6ATd3sxyHrkI0Cr9lncxRW7Q68RQV2MxvFZ(fiKW1oKvcvgcj7ln5rjuziKlbTg0hLqXWqiCEtIG5mSGryuli5uqrAe(6i8ABEv9n7xGqoGXzT30Z4ygaWmS055JrYVnqy8128B2Vads0imkkHcXggAKa
If it doesn't work go to notepad, copy the text and remove all of the spaces from the text then copy it.