Anaphylaxis caused by bites from the European fire ant is not something to worry about, says the expert who confirmed their presence in B.C. in 2010.
Earlier this month, a daily newspaper reported Ralph Olson of New Westminster was the first case of anaphylaxis due to the invasive species. Olson had been helping a friend change a water pump at a lagoon at the Quay in late July. He decided to sit on a pile of rocks, only to be swarmed by the ants minutes later.
“I guess I sat on or near the nest not knowing,” he told the Record. “When I looked down, I could see both my right and left arm were absolutely covered in these ants. I could feel them biting me.”
Olson didn’t think much of it after he removed all the bugs. But then began the itch. By midnight, his entire body was swollen.
“My tongue was so swollen I could hardly get it out of my mouth. My throat was starting to close up,” he recalled, adding he eventually drove himself to Royal Columbian Hospital. Doctors discharged him that day, but he eventually returned as the itching and swelling continued. He would spend a week in hospital taking anti-histamines.
“The anti-histamines would work for about an hour, but then it was back to square one. There were periods of time where I had two to three hours of incredible scratching and itching that you couldn’t stop,” said Olson, who noted the itch was worse than chickenpox.
Robert Higgins, an associate professor at Thompson Rivers University in Kamloops, was the entomologist who verified the presence of the European fire ant in B.C. six years ago. He said Olson’s case is “really rare” and there have only been two other confirmed cases of swelling.
“We have a situation where probably more than 1,000 people have been stung in the Lower Mainland, so this is exceptional,” he told the Record, adding he was recently stung 30 times while collecting colonies but didn’t have a reaction.
“For a small child who’s stung, most of the time it’ll be a scary experience for them because it’s painful, but they probably won’t have anaphylaxis. I say probably because you can’t be sure. Every individual is different,” Higgins said, noting the sting feels like somebody is using a syringe to inject vinegar under the skin.
Even though the European fire ant was confirmed in 2010, Higgins suspects it’s been around for 25 years. It has the ability to displace other ant species. Unlike its European counterpart, which is less aggressive and mates through flight, these ones don’t. Higgins said they “nest bud,” meaning they form high-density nests in close proximity to one other and spread through the transfer of soil.
“When you have so many colonies packed into a relatively small area, that is probably why they become so aggressive once the numbers are well established,” he explained. “Everywhere where we see them now, we have put them there because they’re not flying to those locations after mating. We’ve introduced them.”
