It looks like the lipid envelope is a feature of many viruses, including all influenza viruses:
The influenza virion (as the infectious particle is called) is roughly spherical. It is an enveloped virus – that is, the outer layer is a lipid membrane which is taken from the host cell in which the virus multiplies. Inserted into the lipid membrane are ‘spikes’, which are proteins – actually glycoproteins, because they consist of protein linked to sugars – known as HA (hemagglutinin) and NA (neuraminidase). These are the proteins that determine the subtype of influenza virus (A/H1N1, for example).
It looks like the lipid envelope is a feature of many viruses, including all influenza viruses:
source; Wikipedia and the NIH corroborate.