Rats: intelligent, adaptable, and reproducing fast.
Rats are medium-sized, long-tailed rodents from the genus ネズミ. Two species cause the bulk of our problems in Malaysia — and once they’re inside, they multiply rapidly and bring real disease risks with them.
Norway Rat or Roof Rat?
Most rat problems in Malaysian premises come down to one of two species. They look similar but behave differently — and identifying which you’re dealing with helps determine the right control approach.
The larger, heavier, and more aggressive of the two. Excellent burrowers — they prefer ground level and below.
Smaller and more agile. Prefers to live above ground — climbs walls, runs along beams, nests in roof spaces.
One pair of rats can become 800+ in a single year.
This isn’t theoretical. With sexual maturity at just 5 weeks, up to 5 litters per year, and 6–12 pups per litter, rat populations explode under favourable conditions. Here’s the math.
- Sexual maturity at ~5 weeks of age
- 5 litters per year per female
- 8 pups per litter (conservative)
- ~50% of pups are female
- Daughters begin breeding immediately
- Favourable conditions (food, shelter, water)
Diseases rats actually carry.
Rats are vectors for serious diseases that affect humans and pets. They spread these through their urine, faeces, saliva, and the fleas and parasites they carry.
Bacterial infection contracted from contact with water or soil contaminated by rat urine. Causes high fever, kidney damage, and in severe cases, death.
Severe respiratory disease contracted by inhaling dust contaminated with rat droppings or urine. Causes hantavirus pulmonary syndrome — potentially fatal.
Historically the cause of the Black Death. Rats host the fleas that transmit the bacteria Yersinia pestis to humans. Still occurs occasionally worldwide.
Rats walking across food preparation surfaces or stored foods contaminate them with bacteria from drains, sewers, and waste — causing food poisoning.
Rats destroy more than food.
Rats have continuously growing teeth, which means they need to chew constantly to keep them filed down. The damage extends well beyond your pantry.
Chewed wires & fire risk
Rats chew through electrical wiring, exposing live conductors. This is a leading cause of unexplained electrical fires in properties with rodent infestations.
Structural damage
They chew through wood, plastic, drywall, and even soft metals. Burrows undermine foundations; gnawing damages doors, skirting, insulation, and stored items.
Food contamination
Rats contaminate vastly more food than they actually consume — through droppings, urine, hair, and bacteria from their bodies. A food safety nightmare in any commercial premise.
How rats actually live.
Understanding rat behaviour helps with prevention. They’re not random — their movements are predictable, and their needs are limited.
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Highly social Live in complex hierarchical groups within burrows or nests. Communicate via sounds and scent marking.
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Omnivorous & opportunistic Will eat virtually anything — grains, fruits, meats, garbage, pet food, soap, even leather and paper.
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Travel for food Will travel considerable distances nightly to known food sources. Often follow predictable routes along walls.
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Adaptable to any environment Found everywhere from rural farms to high-rise buildings. They need only food, water, and shelter to thrive.
ネズミ in their environment.
The best way to understand a pest is to watch it. This video shows rats behaving as they naturally would — moving along edges, climbing, foraging, and reacting to surroundings.
Look out for the way they follow walls and edges rather than crossing open ground (a key signal for technicians placing traps), and how confidently they explore once they feel a space is safe — important for understanding why infestations escalate so quickly once the first rats arrive.
Rats in your home or premise — let’s deal with them.
Given how fast rat populations grow, there’s no value in waiting. If you’re seeing droppings, hearing scratching in ceilings, finding chewed wires or food, or just spotted one in your kitchen — book a free inspection. Our rat control service has been protecting Malaysian homes and businesses since 1967.
More from our pest encyclopaedia.
Other common pests in Malaysian homes and premises — many of them often appear alongside rats.


