Mrs S alerted me to a problem in the garden this evening. This is a 5 centimetre long section of one of the stems of a shrub about 1.5 metres high and the same wide... and the whole shrub is covered with greenfly to the same extent as shown in this image. There must be tens if not hundreds of thousands of them but fortunately - for the time being at least - this seems to be the only plant affected.
