Asian needle ants are linked to multiple cases of life-threatening reactions, and the mystical ants continue to spread.
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The stinging, invasive carnivorous ants are slowly spreading across around 20 states.
Last year, at least three cases of life-threatening anaphylactic reaction were reported in Georgia, with the rise of this most (and little known) insect.
“Asian needle ants” will reach peak numbers each year in July and August, but even if you get stabbed one by one, it will still be difficult to find them. They are very small and very well mixed together, so stinging often occurs when someone gets in the way without realizing it during gardening or wood movements.
“Imagine inserting a needle directly into your flesh,” said Benoit Genard, professor of ecology and entomology at the University of Hong Kong, who studied ants in North Carolina. “It’s very sharp and acute pain, but it’s quite local.”
Tracking them has long been a challenge, but researchers now say that the spread of the needle in Asia should not be ignored.
“They’re pretty widespread on the East Coast.” Daniel Sweeter, professor of urban entomology at the University of Georgia. “If you live in an area dominated by hardwood trees, you could have an Asian needle ants under your feet.”
For some people, stab wounds can be life-threatening. For others, it’s an extraordinary pain that can go back and forth for hours.
That’s just one of the mysteries of Brachyponera chinensis. It is roughly translated as “a short, evil ant from China,” but it is actually native to China, Japan and Korea.
It’s hard to track and it’s hard to kill
The invasive insect was first discovered in the United States in Decatur, Georgia in 1932, but has spread so significantly to the southeast that it has been recognized only as a serious pest over the past 20 years. It is now located just north as it is in Connecticut and Florida, Wisconsin and Washington, according to the site antmaps.org. There are also reports of them appearing in Texas.
These ants are carnivorous and are looking for prey such as fly, beetle, grasshopper, and their favorites: termites. Given their hunting habits, they do not place any scent marks as some ants do, making it difficult to return them to their colonies and eradicate them.
“Most ants are invasive in the face and lay pheromone trails to reach food. You can’t miss the half-inch wide ant trail,” Sweeter said. “These remain hidden.”
Dark brown ants live in colonies of leaf trash, rotten logs, fire and mulch. They often occur in residential environments, including parks and urban areas, and are found under the bonds of houses and railways, logs, bricks and pavement. They can also nest in potted plants, under mountains of trees, in lawns.
“People get stinged most of the time while working in the garden,” said Theresa Dillinger, diagnostician at the Virginia Tech Insect Identification Lab. “No one likes putting up bedding plants and suddenly having unexpected pain.”
Worker Ant’s body is about 0.2 inches long, small, dark and shiny, but with bright orange legs and antennae. “They have long jaws and big stingers at the end of the business,” Dillinger said.
They are relatively long and thin, but the “needle” in their name actually comes from their Japanese name, oo-hari-ari.
It is very possible to learn to live with Asian needles, just as we have learned to live with honeybees.
“They aren’t aggressive and don’t flock in the fire ants way,” he said. “Wear gloves and pay attention to what you’re holding.”
Ants like to live in wet areas and around wood, so keeping loose logs and fires away from the ground and dry is one way to avoid invasion, Switter said.
And if you are sensitive to insect stings, it suggests Dillinger: “carry the epipen.”
Painful, long-lasting stab wounds
Genard has been bitten by many different ants and insect species, but the Asian needle ants said that the pain was the only one who knew where it was first very serious, then disappeared and could come back again and again.
“The first initial pain lasted for a few seconds. Then, about five minutes later, when the pain eased, I felt ‘It hurts!” As if someone had stabbed me again in the same place.
“For me, it lasts about two hours,” he said. “But in some people, I know it lasts between 24 and 48 hours.”
For a small number, it can also be fatal. Stings can cause an allergic reaction, in 1% of victims, and poison can lead to fatal anaphylactic shock.
A decades of mystery
Many researchers still don’t understand why these invasive ants spread so much in the US in the 1980s and 1990s.
Asian needle ants, from China, Japan and South Korea, were first identified in Georgia in 1932, but they probably arrived here before that.
“It is highly likely that the ants were introduced in the early 20th century, as they were already discovered in three states by 1934.
As they live in soil and mulch, Genard speculates that they may have come to the US with wooden root balls imported from Asia.
The confusion among researchers is the timing of their spread. The ants remained relatively local until the 1970s, studies show. In 1962, a very thorough inventory of North Carolina ants was carried out by entomologist WG Carter.
“He never found them,” Genard said.
Later between 1991 and 2017, Asian needle ants spread across North Carolina, and are now found throughout the state.
“Something happened,” Genard said. “I couldn’t tell you exactly what.”
The spread of this invasive species causes ecological damage as they spread, studies have shown. As they are predators, Asian needle ants hunt native insects that have evolved to play an important role in the local ecosystem.
For example, no one wants termites in their homes, but in the forest they are an important part of the health of the forest. “They are very important because they help break down dead trees and other organic matter,” Genard said.
Research also shows that local native ants are an important part of seed dispersion for some plants and tree species. When Asian needle ants take over territory, the seeds do not spread.
“Seeds don’t disperse, they just die,” he said.
With warmer weather and wet in some areas, the range of places where these ants can thrive is growing and is expected to invade new areas. According to previous research by Guénard, the amount of North America that could be appropriate is expected to increase by 75% over the next 50 years or so.
How dangerous are needle ants in Asia?
Asian needle ants are not as aggressive as fire ants, and they almost escape when encountering humans. But if they feel pressure from someone reaching for a tree, mulch, or a mountain of soil near the nest, for example, they will stab defensively.
Ants can pose health risks as they can cause allergic reactions in some individuals. Virginia Tech encourages people seeking immediate medical consultation for bee stings when they begin to experience breathing problems or other allergic reactions after being stabbed by an Asian needle ants.
A survey of people living in the Ali Habitat region of South Korea found that 2.1% of people who were bitten experienced a systemic allergic reaction, including 1.2% who had had anaphylaxis. The danger appeared to be the highest among those who experienced repeated stab wounds over time.
Although there is no national reservoir of needle health issues in Asia, when Guénard maintained a website about insects while conducting research in North Carolina, he received 21 health issues reports in Georgia, Kentucky, Mississippi, North Carolina, South Carolina, South Carolina, Tennessee and Washington. In DCs in these cases, at least 12 people reported having a severe allergic reaction, including anaphylactic shock.
The case shows people were logs, gardening and even swimming, but young female ants flew into the swimming pool as they founded a new colony. The stinging events occurred particularly frequently during the summer pack period from April to September, peaking in May to July.
In Georgia, Sweeter called three times about a case of anaphylactic shock after an Asian needle was pierced last year. “I totally hope that some of the people in the emergency room were stabbed by them but didn’t notice,” he said.
There is concern that other stinging insects may have an increased risk of anaphylaxis from needle ants in Asia.
Symptoms reported by the USDA can include:
- Skin reactions include hives, itching, flash or pale skin.
- Hypotension (hypotension).
- Contractions of airways, wheezing, and difficulty breathing.
- Swelling of the tongue and throat.
- A weak and rapid pulse.
- Nausea, vomiting, or diarrhea.
- Dizziness and fainting.
- Psychological symptoms such as a sense of impending destiny.
Unlike stab wounds from invasive fire ants, Asian needle ants stab wounds do not create blisters.
What can you do about Asian needle ants?
This particular type of ants is more difficult to eradicate than other species of ant. Because they are either destroyed to get ants to retrieve poison in the nest, or they do not lay any easy-to-use pheromone trails.
Instead, it uses a process known as tandem carrying.
“One worker ant picks up another worker ant and drags it into a food source and shows where it is,” Dellinger said.
It makes it difficult to feed them, especially as their colonies – usually quite small and flat, but they are difficult to find. “We propose this type of protein-based diet, and it can take time for these ants to return the poison back to the colony,” she said.
So far, there have been no formal management recommendations for species. One published study found good fortune by using baits containing extracts from termite skin.
Dellinger said extensive spraying is useless and in fact harms other important garden species. “Try treating the nest,” she said.
Management is not eradicating it, its goal. This includes removing mulch in areas where ants can cause problems, increasing the wood pile to not wet downwards, looking carefully at the colony (which may take some time), and feeding only in areas where the ants are located.
It is also not easy to identify Asian needle ants that appear to resemble other ant species. “There are a lot of ants out there,” Dillinger said. “Retrieve the microscope.” She recommended contacting a local agricultural expansion if the identification is not certain. “It’s a free service and they help you identify what’s in your property.”