SAN FRANCISCO—Pest control service Orkin released its Top 50 Rattiest Cities List on October 13, and San Francisco ranked fifth “rattiest” city in the U.S.

Orkin ranked metro regions by the number of new rodent treatments performed, including both residential and commercial treatments from September 1, 2019 to August 31, 2020. Chicago ranked top on the list, followed by Los Angeles as the second, New York as the third, and Washington, D.C. as the fourth rattiest city in the U.S.

Orkin points out that people’s concern about rodents has increased this year, since rodents started to find new food sources during the restaurants’ shutdown. They cannot find food waste as usual, so they were scavenging new areas, showing aggressive behavior.

They also anticipate that rodent activity will increase as the colder seasons are coming, since they have to find warm shelters with food and water.

Ben Hottel, an Orkin entomologist commented that “Residential properties offer the ideal habitat for rodents, and once they’ve settled in, they’re capable of reproducing rapidly and in large quantities” on the Orkin’s website. He noted that residents should be aware of rodent activities because they could damage building structures including electrical wires, water pipes and gas lines with their oversized front teeth on their jaws.

Rodents can cause multiple health issues with virus transmission. “Rodents are capable of contaminating food through pathogens that can cause food poisoning or Leptospirosis,” Orkin notes. They can also transmit Hantavirus and Plague.

In order to prevent health and safety risks associated with rodents, Orkin advises people the following:

  • Do not leave out food.
  • Do not let the landscaping run wild.
  • Inspect both inside and outside your home for rodent droppings, burrows and rub marks along baseboards and walls.
  • Look for possible entry points outside your home and seal cracks and holes if any are found.

For more information about rodent prevention, visit