Rat Outbreak and Decline

Rat Outbreak and Decline turns a familiar scavenger into a vast post-disaster force: after The Great Disaster, Rats multiply across the city, consume accessible food, and make Ish and Em fear not only immediate intrusion but also the diseases the animals might carry. The wave subsides when the food supply fails and the Rats’ numbers fall, but their disappearance from view does not mean they are gone. Their rise and retreat show how quickly the absence of human systems can change the balance between people, animals, and disease.

Outbreak and Scale

The warning arrives gradually. Rats appear near Ish and Em’s house, in the street, and in gardens; by the next morning, the wave has engulfed them. They are ordinary in appearance, not unusually large or thin, but their numbers transform the familiar city. The change recalls an earlier surge of Ants, while the Rats’ range spreads across the built-up area and beyond it. Ish and Em begin to understand that a creature ordinarily kept out of sight has become impossible to ignore.

Ish tries to make the invasion intelligible by estimating how fast the population could grow. Consulting his father’s encyclopedia, he finds that a Rat might have about ten young in a litter and produce a litter roughly every month. Because the young females could begin breeding before two months of age, uninterrupted reproduction would multiply the population rapidly. His calculation becomes difficult to sustain: even a doubling each month suggests around fifty million Rats in the area, while a threefold increase points toward approximately a billion. These are estimates, not a count, and Ish recognizes that he cannot determine how many would survive. Yet either figure conveys the same practical reality: there are far too many.

A Household Under Siege

The expansion changes the couple’s ordinary movements. Ish and Em watch the doors carefully, and one Rat still manages to enter the kitchen from an unknown opening. Ish pursues it with a broom; the animal leaps at the handle before he can stop it. The episode makes the infestation concrete at the scale of a single home: the citywide numbers are conjectural, but the breach is immediate. Ish and Em’s caution is no longer a response to distant reports; the threat has crossed their threshold.

The city’s stores reveal how completely the Rats have exploited the food left behind. When Ish ventures to a nearby business center in high boots, gloves, and carrying a stout stick, he finds little food that has not already been consumed or damaged. Packaging is torn and labels chewed, sometimes making the contents difficult to identify. His conclusion is that starvation, rather than disease, is closing in on the swarms. The apparent abundance left by human society has proved temporary: it supports a rapid increase, but cannot feed an indefinitely growing population.

The balance among animals has also shifted. Ish observes that Dogs had seemed to hold their ground without Cats, and reasons that Dogs may have reduced the Cats as well as the Rats. In turn, the Rats’ numbers may have overwhelmed the Dogs, driving them toward the suburbs rather than eliminating them. This explanation is Ish’s inference, not a confirmed account of every animal’s fate. It nevertheless places the outbreak within a wider disruption: the absence of people changes not only the supply of food but also the relationships among the animals that once lived around them.

Disease and the Limits of Knowledge

For Ish, the danger is not confined to food loss or the invasion of the house. He realizes that bubonic plague is a known epidemic among Rats and that infected fleas can move from dead animals to living people. With survivors living amid enormous numbers of rodents, the possibility of transmission becomes a serious concern. Ish responds by spreading DDT through the house and applying it to his and Em’s clothing. Em notices the change, and he has to explain what he fears.

The distinction between a danger and an observed outbreak matters. Ish contemplates the possibility that plague could kill the remaining people, but the episode does not establish that the Rats’ infestation produces a human epidemic. What it does show is how the collapse removes layers of protection. Disease once faced systems of treatment and prevention; now Ish must reason from incomplete knowledge, guard his home, and act on a risk he cannot measure. The episode thus extends the logic of Secondary Kill: people who survived The Great Disaster remain exposed to dangers that civilization had helped contain.

Retreat and Ecological Significance

The decline becomes visible in stages. Ish sees a large Rat attack a smaller one, with another joining the attack; the episode suggests that the animals are no longer simply drawing on plentiful stores. When he later searches shops, he finds that accessible food has been exhausted. Ish understands that the Rats are consuming one another. In his interpretation, this harsh adjustment helps preserve the species: if they all starved without doing so, the population might not survive the crisis. The claim is not that the abundance continues, but that its collapse has consequences for which Rats themselves provide a means of survival.

Day by day, fewer Rats are seen, until one morning they seem to have vanished. Ish does not take this as proof that they have disappeared from the city. Under ordinary conditions, he reasons, Rats keep to narrow passages, holes, and brush-filled gullies; they became conspicuous because their numbers forced them into open places. Disease may also have contributed to the decline, though Ish remains uncertain. Their retreat leaves no comparable visible mass of remains, in part because the Rats have consumed one another; Ish also thinks they must have helped remove human remains left by the original disaster, though he does not investigate.

The episode refuses a simple victory narrative. The retreat ends the period when the couple feels besieged, but it does not restore the earlier human-managed order or establish that the danger has passed permanently. Instead, the sequence moves from sudden abundance to scarcity, from visibility to refuge. Rats are both a threat to isolated survivors and a species adjusting to a changed environment. Their outbreak makes the consequences of human absence legible at street level, while their decline shows that ecological recovery is neither smooth nor governed by human expectations.