Gordon Brown likes to cite his handling of the bluetongue and foot-and-mouth disease outbreaks as evidence of his competence. But a summer of pestilence on the farm now seems a distant memory, as outbreaks of human incompetence crash down on his government.

Monday was supposed to be the start of Labour’s fightback after last week’s series of setbacks. Instead the prime minister’s big speech to business was blotted out by the resignation of his party’s general secretary, embroiled in a party funding scandal.