“Aggressive” Cannibal Rats May Increase as Shutdowns Reduce Edible Waste: CDC
Wed, April 21, 2021

“Aggressive” Cannibal Rats May Increase as Shutdowns Reduce Edible Waste: CDC


The US Centers for Disease Control and Prevention (CDC) recently warned of the “unusual or aggressive” behavior of rats in America caused by more than two months of Covid-19 lockdown. The CDC shared that they received reports of an “increase in rodent activity” in some areas of the country as city-dwelling rodents are not unable to eat street garbage, restaurant waste, and other food sources.

Aggressive rodent behavior during the lockdown

The national health body said that rats were observed eating their young during urban shutdowns as there has been less food available for them to eat. Rodent control and environmental health programs may likewise see an increase in the service requests that are related to rodents. During rat-related inspections and service calls, environmental health practitioners are also encouraged by the CDC to advise business owners and residents to remove conditions that may support and attract rodent presence. Removing heavy vegetation and debris, removing bird and pet food from the yards, using tightly covered garbage bins, and sealing rodents’ access into business establishments and homes are some of the preventive actions advised by the CDC.



Diseases from rodents

It also previously published that mice and rats spread more than 35 diseases worldwide. These kinds of diseases can be spread to humans directly through contact with rodent saliva, urine, feces, or rodent bites. The disease can also be spread indirectly through fleas, mites, or ticks that fed on an infected rat. Effective rodent control in and around the home is the main strategy to prevent human exposure to rodent diseases.

The diseases directly transmitted by rodents are Hantavirus Pulmonary Syndrome, Hemorrhagic Fever with Renal Syndrome, Salmonellosis, Rat-Bite Fever, Plague, Omsk Hemorrhagic Fever, Lymphocytic Chorio-meningitis (LCM), Lassa Fever, and Leptospirosis. In the US, approximately 100 to 150 leptospirosis cases are reported annually. Puerto Rico has the majority of leptospirosis cases followed by Hawaii. Outbreaks of leptospirosis often occur after flooding in endemic areas or heavy rainfall, especially in locations with poor sanitation conditions and housing.



America’s rats getting desperate amid a pandemic

The CDC also mentioned in its latest report that elevated levels of rodent aggression have been observed in New York. There has also been an increase in reports of infanticide and cannibalism in the city.

Urban rodentologist Bobby Corrigan told NBC News that if one takes rodents in an established area or one’s premises and they are doing well, it is often because they are eating well. Since Covid-19 broke out in the country, nothing has changed as people are still doing their trash the same way in their yard just as they’ve always done it – “poorly.” But such is not the case among other rats living in restaurants or other places nearby. Suddenly, life is not working for them and they are left with a couple of choices. These choices, however, are grim since it includes infanticide, rat battles, and cannibalism.

When humans try to take over land, they come in armies and fight to the death to conquer that land. With rats, a new “army” comes in and the army with the strongest rats conquers that area.

Corrigan, who is a consultant for various businesses, including shopping malls, airports, and city health departments, added that these small mammals are like humans. When they are hungry, they are not going to act the normal way. That is the reason why they are fighting one another and adults are forced to kill the young in their nest.

Many restaurants are closed, especially those in tourist attractions, like the French Quarter. Before the stay-at-home order, the French Quarter was famous for its vibrant nightlife and colorful buildings but a viral video in March showed rodents in the streets in search of food. Officials believe that the social distancing measures are to blame.

New Orleans’ Mayor LaToya Cantrell said, “These practices are driving our rodents crazy.” They will find food and water and it puts the homeless in dire straits. New Orleans Mosquito, Termite and Rodent Control Board Director Claudia Riegel also told the local daily that since the rats are hungry, “we want them to eat our bait,” referring to the aggressive pest control measures they are preparing. In the last month, the city already received nearly 500 calls relating to rodents.

Nevertheless, the urban rodentologist assured people not to panic as they are not going to see a rat invasion like what is portrayed in movies. It will be a “block by block” or “case by case” issue in the cities across the United States. Corrigan shared that rodents can smell molecules that are food-related and they can follow those molecules. That is why rats end up where those molecules originate.

CDC moreover advised those in areas of heavy rodent infestations to consider using a repellant that is registered by the US Environmental Protection Agency to lessen exposure to flea-borne disease or prevent flea bites.

Rat-to-human ratio

The rat-to-human ratio is notoriously difficult to gauge. According to a study conducted in 1949 as mentioned in the book "Rats: Observations on the History & Habitat of the City's Most Unwanted Inhabitants," the ratio was 36 humans to one rat in New York. In the 1950s, the estimate was increased to one to one, then dropped again to four humans to one rat.

Animal Planet, a television channel that immerses viewers in life in the animal kingdom, shares that some of the worst rat cities in the world include Deshnoke (India), particularly in the city’s Karni Mata Temple. Rats are not only welcomed in the Hindu temple but worshipped. A person is considered lucky if holy rats patter across their feet. Other places mentioned by the Animal Planet are the Rat Island, which is a part of the Aleutian Islands, Paris, London, Atlanta, and New Orleans.

Although humans do not derive benefits from having rats around, rats have been enjoying a close relationship with humans for hundreds or even thousands of years. The little mammals may have little effect on people but when they go too far, their impact on the human population can also be unbearable. This is why rodent control efforts should always be in check.