Authorities in Thua Thien-Hue Province on Tuesday attributed a recent outbreak of itches and asthma to a household dust mite.
The mite (Dermatophagoides pteronyssinus) causes allergic reations, itchy rashes and asthma, the officials said.
Experts from the provincial Center for Preventing Parasite Malaria said they have not identified the insects per say. When they brought in microscopes, they only noticed dust particles floating through the air, they said.
Nguyen Vo Hinh, director of the center, said based on the residents' stories and bites on their bodies, "there's high chance the insect is the househole dust mite."
Hinh said the tiny mite, lives in bedding, pillows and mats.
It is immune to common insecticides, he added.
On Monday, residents in Hue's Huong Long Ward issued a statement to concerned agencies asking them to identify and eradicate an insect that had appeared in the neighborhood, recently, causing irritating bites.
The residents have used different kinds of sprays to kill the insects but the small winged creature only appears to have multiplied, Vo Quy Tuan, deputy head of the ward, wrote in the statement.
Le Duy Khai, a local resident, said his family has been "alarmed" for the past week by the large numbers of the strange insect.
Khai said the insect is small, like the dermanyssus gallinae (also known as "red mite") an ectoparasite of poultry and birds. He said the creature now occupies every corner of his house, clothes and furniture.
"The problem is, it's attacking people," Khai said.
The insect bites have caused members of his family to break out in itchy rash, he said. Antibiotics ointments and anti-itch creams have not provided any relief, he said.