Dec 7 (Reuters) - Merck (NYSE:MRK) Canada:
* New data from the largest ongoing observational study assessing shingles vaccine effectiveness presented at canadian immunization conference
* As for secondary endpoint, data showed zostavax II had 68.7 percent overall effectiveness against PHN in study
* In the observational effectiveness study, Zostavax II showed vaccine effectiveness against shingles Source text for Eikon: ID:nCNWJv9J2a Further company coverage: MRK.N