Finally, even though conventional vaccine development has been notoriously difficult for RSV, the recombinant RSV Mmutant virus characterised here for lack of pathological effects on the host mitochondria (and previously by Li et al. [8] for impaired transcriptional inhibition), may be considered as having potential as an attenuated virus vaccine candidate; as already mentioned, the immune responses to the virus are clearly altered in mice (e.g., increased RANTES production), in parallel with reduced viremia/lung inflammation [8]. Here, CCL5 is linked to inflammatory response.