Intervention strategies for human respiratory viruses with a major impact – influenza virus, Respiratory Syncytial Virus (RSV) and  human MetaPneumoVirus (hMPV)– are largely limited to the use of classical vaccines against influenza with inherent limitations like a relative low efficacy. For the other two viruses no vaccine is currently available. It is postulated that when the mechanisms governing the induction, maturation and effector stages of the host response to these viruses are understood at the molecular level, optimal use can be made of newly emerging molecular virological and immunological techniques and insights, to create a platform for the rational design of vaccines and other intervention tools.
The development of a vaccine against RSV infections has largely suffered from the outcome of clinical vaccination trials in the sixties with classical inactivated vaccines. Rather than protect the vaccinees, these proved to predispose themfor more serious subsequent RSV infections which in some cases even proved to be fatal. The underlying mechanism for this phenomenon is still poorly understood, although it has been reproduced in mouse and macaque models. The phenomenon proved to be associated with a skewed T cell response upon vaccination and subsequent infection, although the exact mechanisms at the molecular level is still elusive.
The development of a vaccine and other intervention strategies against hMPV infections may be expected to be associated with the same kind of problems as those observed for RSV infections, given the virological, clinical and epidemiological similarities between the two viruses and the diseases they cause. Therefore the same strategy followed for host-RSV interaction studies will be applied to for studying host-hMPV interactions.
Vaccination strategies for the control of the counterparts of influenza viruses, RSV and hMPV in the animal world are limited to the use of vaccination programs for some of these viruses in some domestic animal species, albeit with varying success. The VIRGO project will focus on chicken-influenza virus and chicken-MPV (Avian PneumoVirus) interaction studies.