So, with World War Moo, Michael Logan returns readers to the Britain overrun by virus infected animals that essentially want to pass on infection via biting or sex.
Which is, of course, why Great Britain remains under forced blockade with no one getting in or out.
The zombies have set up BRIT, basically an ad hoc government to run things until the situation resolves one way or another, under Tony Campbell. Tony made a cameo in the first book, threatening to eat intrepid journalist Lesley McBrien during a televised interview. However, the Russians, Americans, and Chinese plan on using a series of nuclear weapons and planned invasion (Operation Excision) to eliminate the virus and make the Isle habitable for normal folks again.
On the islands itself, we have Ruan, who is immune to the virus, who ends up finding a group of infected who have learned to control the impulses associated with infection by sexual conduct, marijuana, and yoga. Unsurprisingly, Geldof Peterson's mother Fanny (who survived the pig stampede it seems) is running the resistance. This, of course, leads to Geldof and his grandfather hiring mercenaries to get her out. Geldof winds up going in with the mercs, because of course he does.
Tony, in the meantime is learning to control his viral urges by channeling Mr. Spock from Star Trek. Not easy, since a group named Blood of Christ is looking for ways to get the virus everywhere else, thinking it's G-d's judgement upon mankind. Tony is attempting two different plans to reconcile Britain with the world, one of which is dropping infected blood bombs on France via Britain's last remaining nuclear submarine, the other convincing people that Britain can control itself.
Lesley, bless her heart, winds up getting pulled in when she reposts about Operation Excision, then promptly gets extraordinarily renditioned (along with her source) to Scotland.
It's a little les subtle with its metaphores than the first book, and the rage virus seems to have been retooled for this one. But still, there are worse ways to spend reading.