1a Madam fed up, reportedly (4)
B?W?
7d Invalid, not surprisingly, likes lettuce for starters (4)
N?L? NULL?
27a Vehicles to carry instruments failing to start (4)
???S
19a Fever expected to grip almost 43% of England (6)
?E???? DENGUE?
24a Boxer once touring west of Ireland, round Mayo, in part? (5)
??O??
26a Make untidy female in club start to listen (8)
??S?????
Yes, indeed, it is Unsurprisingly - my error.
Have a few more;
27a Vehicles to carry instruments failing to start (4)
???S
20d For audience, could be chaps making appearance (5)
G?i?E GUISE?
18d Welsh, for example, Frenchman's acquired (6)