Flies

Flies are a vector that can carry disease in the state of Alabama.  More to come soon.

Mosquito

Mosquitoes are insects belonging to the order Diptera, the True Flies. Like all True Flies, they have two wings, but unlike other flies, mosquito wings have scales. “Mosquito” is a Spanish or Portuguese word meaning “little fly”.

There are over 3,000 different species of mosquitoes throughout the world; currently 176 species are recognized in the United States. There are over 50 species of mosquitoes known to occur in Alabama.

Only female mosquitoes have the mouth parts necessary for sucking blood. While biting using their long, piercing sucking proboscis, they inject an enzyme that inhibits blood clotting. They use the blood not for their own nourishment but as a source of protein for their eggs. Mosquitoes use exhaled carbon dioxide, body odors and temperature, and movement to nd a host.  Once a host is found, the female mosquito will use molecular cues from the host’s skin to determine whether it is suitable for a blood meal. One of the most elective mosquito repellents, DEET, scrambles these molecular cues where they are received on the legs of the mosquito so the mosquito does not know it has landed on a suitable host.

Males differ from females by having feathery antennae and mouthparts not suitable for piercing skin. A mosquito’s principal food is nectar or similar sugar source.

Some mosquito species are capable of transmitting diseases such as malaria, yellow fever, dengue, lariasis and encephalitis including St. Louis encephalitis (SLE), Western Equine encephalitis (WEE), LaCrosse encephalitis (LAC), Japanese encephalitis (JE), Eastern Equine encephalitis (EEE) and West Nile virus (WNV)] to humans and animals.  They also transmit heartworm disease (Dirolaria immitis) to dogs and cats, and sometimes wild carnivores and the occasional human.

Rodents

The rats and mice considered pests are often referred to as commensal rodents. The word commensal means “sharing one’s table.” This is appropriate as these rodents have shared man’s table for centuries.  The term “rodent” means “to gnaw.” Like all rodents, rats and mice have a single pair of chisel-like incisor or front teeth that grow throughout their lifetime. Their teeth are kept sharp and are sized due to their guarding against one another and by the pests’ continuous gnawing on a variety of objects.

The three most important commensal rodents are:

• House Mouse
• Norway Rat
• Roof Rat

Rodents and disease
Rodents have been a major cause of death and disease for many years. Today, the threat is not as significant as it once was because of sanitation and rodent control programs. However, the threat is still evident, and the potential of disease must always be kept in mind.

Some rodent-transmitted diseases include:

• Plague — This was caused by a bacteria that is spread from rats to people by the oriental rat ea. The Black Death that killed 25 million people in Europe during the 14th century was the result of Plague. Plague does not exist in commensal rodents in the ., but it is still found in some native rodents, such as brown squirrels, in the western United States and other parts of the world.
• Salmonellosis (acute food poisoning) — Salmonella bacteria can thrive on decaying food, meat, and poultry, and in sewers, livestock facilities, septic tanks, accumulated garbage, and other unsanitary environments. Rodents visit contaminated areas and then visit homes and food facilities, causing the spread of the salmonella. The bacteria grows in the intestinal tract of rodents and spreads through food contaminated with rodent feces.  There are about two million cases of salmonellosis in the United States each year. Current research shows that rats and mice do not play a major role in the spread of salmonellosis to humans but can signicantly spread the disease to animals.
• Rat-bite fever — Rat bite fever is caused by a bacteria that lives in the saliva glands of both rats and mice. It causes unlike symptoms that last for several days and in severe cases can be deadly. Although it is not
  common in the United States, it is possible many cases are unreported, as the symptoms can be mistaken for the u. Conservative estimates place the number of people bitten by rats and mice between 14,000 and 20,000 annually. Typhoid and dysentery — Rats have been shown to carry the organisms of these diseases.
• Trichinosis — Rats serve as vectors by carrying the trichina worm, which is responsible for trichinosis. This disease occurs when the worm is ingested when eating undercooked pork.
• Hantavirus — There were several outbreaks of this virus in the southwestern United States from 19931995. Hantavirus has been associated with deer mice, not commensal rodents.

Physical Abilities and Senses

Rats and mice cannot see well beyond 3 or 4 feet, but they are sensitive to motion up to 30-50 feet away. They are color-blind, but are sensitive to and may avoid light-colored and reective objects. Therefore, rodents are most active during the night hours when light levels are low and they can rely primarily on their other senses, especially the sense of smell, touch and hearing.

Rodents have a very strong sense of taste, which can lead to rejection of bait if they are contaminated with odors or other chemicals. To ensure acceptance of bait, use fresh, food-quality grain ingredients.
Smell is one of their most important senses. Rodents mark objects and pathways with urine or other secretions, then use their sense of smell to recognize the odors for guidance, to distinguish members of their own colony, and to tell if a stranger is threatening.

Rodents are able to hear at high frequencies.  They use hearing to locate objects within a close range.
If rodents cannot go around an object, if possible they will tunnel through it. They can gnaw through many materials, including cinderblock, aluminum siding, glass, and improperly cured concrete. They can squeeze through very small openings — as small as 1/2” for a rat and 1/4” for a mouse.