Friday, September 27, 2013

NPMA Technical Update: The Importance of Bed Bug Salivary Glands

NPMA Technical Update: The Importance of Bed Bug Salivary Glands

Drs. Jerome Goddard and Kristine Edwards of Mississippi State University have investigated the effects of bed bug saliva on human skin. Secretions from salivary glands have long been thought to be the cause of dermal reactions among certain people bitten by bed bugs, but there was insufficient supporting evidence. The scientists were able to demonstrate the role of saliva by removing the salivary glands of bed bugs and allowing them to feed on a person known to produce a dermal reaction upon being bitten. Although the volunteer could feel the bite of a bed bug that lacked salivary glands, the bug was unable to feed and her skin did not react as it did to a normal bed bug bite. In a second experiment, a salivary extract was prepared from bed bugs and applied topically to the volunteer's skin. Within 36 hours, the volunteer reported itching and a visible dermal reaction. This research presents strong evidence that salivary glands are important to both feeding and likely contain allergens that can cause adverse reactions in victims.  

This paper, "Effects of Bed Bug Saliva on Human Skin", was published in the American Medical Association Journal of Dermatology in March of 2013.

Tuesday, March 26, 2013

Winter Ants by Ralph H Maestre BCE


Winter Ants by Ralph H Maestre BCE

Lasius niger Black Garden Ant
A potential pest ant is the Black Garden Ant, Lasius species, which has workers approximately 2-5 mm in length and is monomorphic (all the same size). They have several different species with various body colors. Black Garden Ants are found throughout the US. This ant forms mega-colonies with multiple queens.
They tend aphids for honeydew and eat living and dead insects. They love sugar-based products inside home. The colony size may reach over 15,000 ants and cover very large areas. One colony in Europe covered northern Spain, southern France into northern Italy. That is like saying one colony covering an area from New York City south to Washington DC. This may be an exaggeration but you get the idea. Anything you do on a property may only be like trimming the finger nails on a human. The body is so large that the nails just grow back. This is to say that the colony will bounce back very quickly. A very aggressive approach to pest control including both the inside and outside of the property would be required.

Prenolepis impairs False Honey Ant or Winter Ant
The winter ant is in reference to its foraging at temperatures barely above freezing during the cooler months. False Honey Ant is an unfortunate name, since the storage product in the corpulent young workers of these ants is fatty, not sugary. The body lengths for the worker is 2.5-3.5mm, the queen about 8mm, male 3-4mm. The ant has a very shiny head, thorax, and abdomen very dark brown in color. The legs and antennae of live specimens are medium brown at base, smoothly shading to pale yellow at tips (this color arrangement gives the overall impression of an insect that is very dark in the middle and very pale at the extremities). The range for the winter ant is most of the United States, plus southern Ontario and Mexico. This ant usually nests in the soil with some clay content in wooded situations or occasionally constructing a chamber under a rock or log. This ant is often associated with oak woodlands of various sorts (or scrub oak thickets in the west), but also (beech-) maple.

The winter ant often build their nests deep underground, staying inactive during the summer months, and returning to activity when the weather cools. They are the earliest to swarm of our cool climate North American ants.

The workers feed on honeydew, secretions of flowers, sap flows, exudates from galls, earthworms and arthropods (usually as carrion), and ripened or decaying fruit. The life cycle o f the males and females are reared in late summer, then overwinter in the underground nest, and take their nuptial flights in the spring. Young workers are "overfed" and swell with fat, from which a nutritious glandular secretion is produced. This becomes the main food upon which the year's single brood of workers and alates (winged ants) are reared.

Pachycondyla chinensis Asian Needle Ant

One of the few ants that are specialized for cold temperature foraging; they can be found foraging even at near freezing temperatures, where they are often the only ants visibly active. However, their range does not extend into the far north, despite their cold tolerance.

Pachycondyla chinensis, the Asian needle ant, was first detected in the United States in Dekalb County, Georgia in approximately 1932. This species is an average sized, dark brownish-black ant with an evident stinger. It is considered an invasive species that establishes large populations that may displace native species. Reactions in humans from the sting o this exotic species range from mild to severe, sometimes with long lasting symptoms. Consequently, the Asian needle ant poses an emerging health threat throughout its range, as well as areas to where it may be spreading. However, it is not overly aggressive. Stings typically result from handling workers or by winged queens landing on individuals and becoming trapped between clothing layers and skin.

Asian needle ant typically nests in soil in somewhat damp areas, especially below stones, in rotting logs and stumps, or other debris. In urban settings it may also be found under mulch, railroad ties, bricks and pavers. Colony size ranges from less than 100 individuals to several thousand, and multiple queens may be present. Unlike many introduced, invasive ant species, it can nest in natural wooded habitats. This species appears to prefer termites as a food source.

This introduced species is thought to have been introduced from Japan. In the United States it is known to occur in Alabama (MEM record), Connecticut, Florida, Georgia, South Carolina, New York, North Carolina, Tennessee, and Virginia.

Sources:
Mississippi State Entomological Museum, Asian Needle Ant
Wikipedia, False Honey Ant or Winter Ant