In the midst of the summer heat, a invasion of black moths is currently affecting several localities in the northern suburbs of Buenos Aires.
There, these allergenic insects have caused numerous cases of dermatitis in people who came into contact with them.
This is the species Hylesia nigricans, or “burning worms”, which later transform into enormous butterflies and dark ones that appear during the summer.
In the Province of Buenos Aires, these are mostly found in the north of the AMBA, in areas of high humidity.
In reality, experts explain, the insect itself does not bite or sting, but what causes allergic reactions are the microscopic hairs they release as a defense mechanism.
Northern zone on alert due to the invasion of black moths
The invasion of black moths in recent days has been concentrated mainly in the municipalities of Tigre and Escobar, with abundant vegetation.
In particular, neighborhoods near the Delta and residential areas with pools reported the highest number of cases.
In this regard, the health area of the municipality of Tigre confirmed the massive presence of these moths.
“It is common at this time of year for these areas. The particles they release defensively are very allergenic,” indicated the organization.
“The welts are like tiny spider bites, one next to the other, in large quantities. They are red and itch a lot,” said Gimena, a resident of Escobar whose two-year-old daughter developed a rash all over her body.
How the insect acts
In reality, the black moths that invade the AMBA do not make direct bites, but rather shed stinging hairs easily as a form of protection.
These then adhere to skin, clothing, and sheets, causing inflammatory reactions.
“It is not a bite, but it causes a contact dermatitis due to the microscopic hairs that both the larva and the adult moth have on their bodies,” explained dermatologist Luciana Acosta.
In this invasion, the black moths are especially attracted to light sources. Therefore, pools illuminated at night have become critical points of accidental contact.
The geographical expansion of the phenomenon of black moth invasion
The invasion of black moths represents an expanding phenomenon. “The striking thing is that we were not an endemic area, but it was more frequent in the coastal area,” explained Acosta.
The larvae form from September, and in January they transform into butterflies. This summer, the problem has recurred with greater intensity in areas that were not previously affected.
“A few years ago, it started in the Delta area and now it is moving to the areas of Escobar, Pilar, places with lots of vegetation,” added the specialist doctor.
The symptoms and their treatment
The allergic reaction varies from person to person, although most develop some manifestation. The main symptoms include:
- Skin redness
- Intense itching
- Spots or welts
- Burning sensation
- Local inflammation
“The symptoms are usually redness, intense itching, spots or welts, burning sensation, or local inflammation,” detailed Acosta.
The condition lasts between seven and 14 days, is not contagious, and with adequate treatment the symptoms are well controlled.
The treatment consists of corticosteroid creams and antihistamine syrup. In case of mild symptoms, the area should be washed with cold water and consulted at a health center.
To avoid contact during this invasion of black moths, experts recommend not turning on the garden lights at night or leaving clothes hanging outside.
“The most advisable thing is to avoid touching them and let them fly away on their own,” indicated the Tigre Health department. If the dead insect is seen, they also do not recommend approaching because it still contains the stinging hairs.
In case of direct contact, rinse the area well and change clothes. “Try to wash with water and soap. If possible, do not rub, scratch, or apply alcohol,” concluded Acosta.
In the event of widespread reactions or difficulty breathing, one should go to a nearby health facility for injectable treatment in an emergency.
