The family of a 10-year-old boy who died after being bitten by a rat purchased from a San Diego-area Petco filed a lawsuit seeking $20 million in damages in February of 2014. On Thursday, a jury ruled in Petco's favor, finding that the retailer was not liable or negligent in the 2013 death of Aidan Pankey.

On June 12, 2013, Pankey was rushed to the hospital with severe stomach pain, where he later died. According to the San Diego medical examiner, Pankey's cause of death was determined to be rat bite fever, a streptobacillus infection caused by exposure to infected rodents.

The Centers for Disease Control later confirmed that the Petco rat was indeed infected with streptobacillus moniliformis.

Grandmother purchased rat as a gift

Sharon Pankey, the victim's grandmother, was the customer who purchased the rat. Even though she was disheartened by the jury's decision, she told San Diego's NBC-7 that she was glad to have had the opportunity to bring rat bite fever to the public's attention. According to NBC-7, attorneys for the Pankey family argued that Petco failed to adequately warn Sharon Pankey about the dangers of rat bite fever, even though an investigation revealed that approximately 50% of rats sold by the retailer carried the bacteria.

Petco's lawyers say written warning was adequate; jurors agree

Kimberly Oberrecht, an attorney representing Petco, argued that rat bite fever, while rare, is treatable, adding that out of 5 million rats sold by Petco, there have only been 45 reported cases of people getting sick from infected rats.

Petco's lawyers also argued that the company couldn't possibly guarantee that each of the millions of rats and mice it sells are free of the potentially deadly bacteria.

Barney's Pets is the company that supplies rats to the retailer, and Pankey's lawsuit alleges that the pet supplier, as well as Petco, knew that some of its rats were infected.

However, the defense argued that the retailer does in fact warn customers of the potential dangers of owning a pet rat -- not verbally, but printed on the general instruction form that comes with the purchase of each rat.

Sharon Pankey later discovered that customers can request to have their rat tested for rat bite fever -- a lifesaving piece of information she discovered too little too late. "If you buy a rat from Petco, you can request they be tested for rat-bite fever. I never knew that," Pankey told reporters.