Coping with genetic diversity: the contribution of pathogen and human genomics to modern vaccinology

Lemaire, D.; Barbosa, T.; Rihet, P.

Braz J Med Biol Res 45 (5) Infectious agents remain a major cause of morbidity and mortality worldwide in spite of advances in hygiene, drug development, and vaccines. The emergence of drugresistant strains of infectious agents (including bacteria, viruses and parasites) and emerging diseases caused by either newly identified infectious agents or newly identified pathogen strains (e.g., severe acute respiratory syndrome corona virus, H5N1 avian flu, H1N1 swine flu) are a global health concern. Vaccine development therefore appears to be essential to limit the spread of emergent and re-emergent diseases. However, the development of vaccines faces major difficulties highlighted by the absence of efficient vaccines against major health concern infectious diseases, such as malaria, tuberculosis, and AIDS (1) . The difficulties range from i) the incapacity of inducing host protective responses due to inadequate adjuvant, dose, route of immunization, or candidate vaccine antigens with low immunogenicity, high rate of genetic variation, or limited accessibility to the immune system, to ii) high interindividual variability in the response to the vaccine observed as highly variable adverse event risk or protective efficacy, which are partially determined by the genetic background and the immune status of vaccine recipients.