The name of a genus of mosquitoes that consists of a group of closely related species. Until recently, the genus Aedes was used "broadly" to include a large number of species grouped into several subgenera of the genus Aedes. However, in 2002, a mosquito authority published a revised taxonomy in which the subgenus Ochlerotatus was "raised" to the level of genus. The effect of this was to change scientific names of a large number of species previous known as members of the genus Aedes. For example, a very common floodwater mosquito Aedes trivittatus became Ochlerotatus trivittatus and the eastern tree hole mosquito Aedes triseriatus became Ochlerotatus triseriatus. This issue is complicated and contentious, and some mosquito authorities are lobbying to return to the taxonomy that existed prior to the change in 2002.
The name given to an antigen that is capable of inducing the production of a specific type of antibody (IgE) in a very small percentage of people. Such individuals are prone to develop allergies. Common examples of allergens include pollen and certain chemicals contained in venoms of social bees and social wasps.
A reaction involving the immune system that is associated with IgE antibody and the release of specific chemicals such as histamine from cells of the immune system. Symptoms include inflammation, increased vascular permeability, and bronchial and visceral smooth muscle contraction. This type of reaction also is known as "immediate hypersensitivity."
A designation given to a species of arthropod that contributes to the buildup and transmission of a disease-causing agent by transmitting the agent among vertebrate hosts. For example, Culex restuans is an early season mosquito whose females feed primarily on birds from which they acquire West Nile Virus. Infected mosquitoes then transmit the virus to susceptible birds during subsequent blood meals. This increases the number of birds harboring the virus, and infected birds can serve as sources of virus to additional mosquitoes that feed on them.
A disease of vertebrate animals caused by bacteria in the genus Anaplasma, which are intracellular parasites that undergo development within a type of white blood cell known as a granulocyte.
This is an extreme form of allergic reaction to an allergen in a sensitized person. The reaction can cause constriction of airway passages, extensive swelling of tissues in the throat area, and cardiovascular collapse due to rapid drop in blood pressure.
A member of the insect order Hymenoptera (ants, bees, and wasps), all species of which are social and exist in colonies consisting primarily of females known as "workers." Ants are highly diverse biologically, and it is not possible to generalize about them. For example, depending on the species, ants differ in regard to where they nest, what their larvae are fed, and the chemical composition of their venoms. Very few species in the U.S. are a medical risk, the most important being fire ants.
A type of chemical (an immunoglobulin) produced by certain cells of the immune system that binds to an antigen, often with a high degree of specificity. Antibodies are involved in defending against viruses, bacteria, and parasites that invade our body. One type of antibody (IgE) forms in response to antigens that are involved in allergic reactions.
A chemical that is capable of inducing antibody production when introduced into a person. Antigens include viruses, bacteria, and parasites, and also agents of allergy such as pollen and certain chemicals in the venom of social bees and social wasps. Antigens involved in allergies are often referred to as allergens.
The term used as a short cut for arthropod-borne virus. It refers to a group of viruses that undergo essential development and multiply in arthropods such as mosquitoes and ticks. Nearly every arbovirus is dependent on arthropods for transmission from a reservoir host to a susceptible vertebrate host. However, certain arboviruses, for example West Nile Virus, can be "shed" by an infected vertebrate such as a bird and be a source of infection to a human.
The propensity of certain individuals to produce IgE antibody in response to allergens and thereby become sensitized. Such individuals are referred to as being atopic. They may be subject to hay fever allergy, house-dust mite allergy, food allergy, and allergy to stinging insect venom, but not necessarily all of them.
The physiological process that allows the development of an initial batch of eggs by a blood-feeding arthropod that has not had a blood meal. For example, a female Culex pipiens mosquito can develop one batch of eggs derived from energy reserves accumulated during feeding by the larval stages. The development of a second batch of eggs requires a blood meal, however, and any additional batches of eggs each would require a blood meal.
This is a disease of vertebrate animals caused by protozoa in the genus Babesia, which are intracellular parasites that undergo a complex cycle of development inside red blood cells.
This is a group of bacteria that includes three species that can cause human disease, two of which are vector-borne. Bartonella quintana, transmitted by human body lice, is the cause of trench fever and Bartonella bacillifornis, transmitted by sand flies, is the cause of Oroya fever, neither of which occurs in the U.S.
This is a type of circulating cell of the immune system with structural and functional similarities to mast cells. They contain chemicals such as histamine that contribute to allergic reactions.
A member of the insect order Hymenoptera (ants, bees, and wasps), the larval stages of which are fed pollen. This is in contrast to wasps, the larval stages of which are feed meat, typically spiders and other insects. The vast majority of species of bees are solitary and of no medical risk. The most important exception is the honey bee, a social species that possesses a venom associated with allergic reactions.
Weakness on one side of the face caused by paralysis of a facial nerve resulting in drooping of an eyelid and an inability to smile or furrow one's brow. In cases associated with Lyme disease, the cause is the invasion by Borrelia burgdorferi spirochetes of the nerve that controls muscles of the face.
This is a species of arthropod that acquires a disease-causing agent from an infected wild animal and subsequently transmits the agent to a human. For example, Culex salinarius is a mosquito whose females feed readily on both birds from which they may acquire West Nile Virus and on mammals to which they may transmit the virus during the taking of a subsequent blood meal.
The name of a condition associated with the re-occurrence of epidemic typhus fever in a human who survived an infection and in whom the disease agent (a bacterium) persisted without symptoms for many years. People with a Brill-Zinnser infection can be a source of the bacteria to human body lice and thus serve as a potential start of an epidemic.
This is the extended period of cold temperatures necessary to "break" diapause of delayed-hatching eggs of Aedes, Ochlerotatus, and Psorophora mosquitoes. After cold treatment, delayed-hatching eggs are capable of hatching if covered by water for at least several days.
This is the process of growth and development of the vast majority of insect species in which an individual insect develops through several larval stages and then a non-feeding pupal stage before reaching adulthood. For example, mosquitoes have four larval stages and a pupal stage in which the last larval stage is transformed into a flying adult.
This is the name of a genus of mosquitoes that consists of a group of closely related species. Several species of Culex are involved in the transmission of arboviruses, including West Nile Virus and Encephalitis viruses.
The designation of a vertebrate animal that is infected with a disease-causing agent, but is not a source of the agent to another vertebrate or to an arthropod vector. For example, humans can be infected with an arbovirus, but we do not develop levels of the virus high enough to be passed to another arthropod and, with rare exception, to another human.
This is the acronym for the chemical repellent N, N-diethyl-m-toluamide ("diethyltoluamide"). DEET has been thoroughly tested and is widely considered to be the most effective insect repellent. When used as directed at concentrations of 15-30%, DEET is considered safe for adults and children over two years of age.
Eggs of Aedes, Ochlerotatus, and Psorophora mosquitoes that are laid on moist surfaces or just above the high water mark in sites in which standing water has receded. These eggs then must remain dry for at least several days before they are capable of hatching if subsequently covered by water. Delayed-hatching eggs may remain viable in a dry condition for weeks, months, or perhaps several years.
A method for treating allergies that involves repetitive administration of minute doses of a venom to which an individual is allergic. For example, a person who is known to be allergic to honey bees is injected with minute doses of pure honey bee venom. The process of desensitization often prevents severe allergic reactions on subsequent exposure to the same allergen, but the mechanisms involved are not fully understood.
The type of dormancy that persists through harsh environmental conditions such as winter during which growth, development, and reproduction does not occur. For example, some Indiana mosquitoes over-winter as eggs (species of Aedes, Ochlerotatus, and Psorophora) while others over-winter as mated females (species of Anopheles and Culex). In both cases, growth, development, and reproduction does not begin until after diapausing eggs or diapausing females have experienced a "cold-treatment" of a duration approximating the passage of winter.
Eggs of Anopheles and Culex mosquitoes that are laid directly on top of shallow, standing water and hatch within two to three days. Direct-hatching eggs do not survive if they are removed from water and they do not over-winter. Mosquitoes that lay direct-hatching eggs over-winter as mated females.
A period of dryness of at least several days that must be experienced by delayed-hatching eggs laid by Aedes, Ochlerotatus, and Psorophora mosquitoes. Following completion of a dry treatment, delayed-hatching eggs are capable of hatching if covered by water for several days.
A disease of vertebrate animals caused by bacteria in the genus Ehrlichia, a group of intracellular parasites that undergo development within white blood cells. One species of Ehrlichia develops inside monocytes and another species develops inside granulocytes.
(see erythema migrans)
An inflammation of the brain caused by an infectious agent including viruses such as measles, mumps, hepatitis, chickenpox, and arboviruses. Arboviral encephalitis can result in death or sequelae in survivors of an acute infection.
An inflammation of both the brain and the spinal cord caused by an infectious agent. Certain arboviruses are capable of causing encephalomyelitis, for example, eastern equine encephalitis virus.
A chemical antidote to certain allergic reactions that upon injection increases cardiac output (to counter a sudden fall in blood pressure) and inhibits further release of chemicals such as histamine from mast cells. A physician may prescribe an "epi kit" to patients who have a diagnosed allergy to honey bee or yellowjacket venom, for example. The kit contains a syringe pre-loaded with a dose of epinephrine, which should be injected immediately after the allergic person is stung.
A reddish skin rash associated with Lyme disease that is caused by infection and initial spread of Borrelia burgdorferi spirochetes in the vicinity of the bite of an infected tick. The rash can vary in form and size, but often develops into a "bulls-eye" pattern.
A disease of humans that is caused by a group of parasitic nematode worms which are transmitted to humans by species of mosquitoes in several different genera. For example, "urban filariasis" is a disease that afflicts people in the rapidly growing cities in tropical and subtropical in which the number of humans overwhelms basic services such as housing, potable water, and disposal of sewage. Culex mosquitoes thrive in such sites and are the vectors of the nematode worms.
This is a type of white blood cell that circulates in the blood and is a functional part of the immune system involved in destroying microorganisms that enter our bodies. However, certain species of bacteria in the genus Anaplasma and the genus Ehrlichia survive inside granulocytes and complete an essential part of their life cycle within them.
A chemical stored inside mast cells and basophils that is one of the important contributors to allergic reactions. Histamine causes increased vascular permeability and contraction of smooth muscle in airway passages and in the intestines.
The common name typically given to a group of social wasps that construct paper nests in exposed sites such as on tree branches, in shrubs, or under eaves. The combs that contain cells in which larvae are reared are enclosed in a thick paper envelope and thus are not visible. The most common example is Dolichovespula maculata, the so-called "white face hornet" or "bald face hornet." (Note: the name hornet also is given to Vespa crabro, the so-called "European hornet" or "giant hornet," but this species typically builds a nest inside hollow trees or sometimes inside dark attics.)
The type of allergic reaction responsible for diseases associated with IgE antibody together with the release of chemicals such as histamine from mast cells. Immediate hypersensitivity reactions are associated with rapid drop in blood pressure, constriction of respiratory passages in lungs, and extensive swelling of tissues. The most severe hypersensitivity reaction is systemic anaphylaxis.
The type of antibody associated with allergic reactions. IgE antibody is formed by the immune system in response to the introduction of an allergen in individuals who are prone to developing allergies. For example, in these individuals an allergen in the venom of a social wasp can stimulate the production of IgE antibody specific for that allergen. As a consequence, these individuals are considered sensitized to the venom, and a subsequent sting by a social wasp can result in a serious allergic reaction.
A vertebrate animal infected with a disease-causing agent that is not essential to the development and transmission of the agent. For example, humans can be infected with West Nile Virus (and may suffer severe illness or death), but we are not essential to the development and transmission of the virus.
No defintions for words starting with J.
No defintions for words starting with K.
This is a repellent derived from an oil extracted from a species of eucalyptus tree. The Centers for Disease Control and Prevention (CDC) recommends it for people seeking an alternative to DEET. However, research has shown it to be less effective as a repellent than recommended concentrations of DEET.
This is a type of white blood cell that is an important component of the immune system involved in destroying microorganisms that enter our bodies. Macrophages are found in a variety of tissues including the central nervous system, liver, lungs, and bones.
A disease of humans caused by protozoa in the genus Plasmodium that are transmitted to humans by mosquitoes in the genus Anopheles.
This is a type of cell of the immune system, and the major contributor to allergic reactions. Mast cells are filled with chemicals such as histamine that are released when a specific allergen attaches to them in a person who has been sensitized to the allergen.
An inflammation of the lining of the brain and the spinal cord caused by an infectious agent including viruses such as measles, mumps, hepatitis, chickenpox, and arboviruses.
This is a type of white blood cell that circulates in the blood and is an important part of the immune system involved in destroying microorganisms that enter our bodies. However, certain species of bacteria in the genus Ehrlichia survive inside monocytes and complete an essential part of their life cycle inside them.
A bloodsucking arthropod that causes discomfort when biting, but is not known to be involved in the transmission of a disease-causing agent. For example, females of Aedes vexans, a very common floodwater mosquito, feed readily on humans and are significant pests, but are not known to transmit West Nile Virus.
The name of a newly recognized genus of mosquitoes that consists of a group of closely related species. Until recently, Ochlerotatus was treated as a subgenus of the genus Aedes. However, in 2002, a mosquito authority published a revised taxonomy in which the subgenus Ochlerotatus was "raised" to the level of genus. The effect of this was a change in scientific name of a large number of species previous known as being in the genus Aedes. For example, a very common floodwater mosquito Aedes trivittatus became Ochlerotatus trivittatus and the eastern tree hole mosquito Aedes triseriatus became Ochlerotatus triseriatus. This issue is complicated and contentious, and some mosquito authorities are lobbying to return to the taxonomy that existed prior to the change in 2002.
This is the term that is applied to the laying eggs by a female arthropod. In the case of most species of mosquitoes, ovipostion occurs during a relatively narrow period of time, usually at night, and is in response to chemical and/or visual cues associated with a particular habitat. For example, oviposition by Culex pipiens, the house mosquito, typically is in response to foul odors associated with polluted water.
A complex structure on female ants (nearly all species), bees, and wasps that functions as a sting or "stinger" through which venom is introduced into a person who is being stung. Note: in nearly all other insects the ovipositor is involved in laying eggs.
These are common names given to a group of social wasps in the genus Polistes. Nests of Polistes wasps consist of a single "comb" of cells in which larvae are reared. Polistes nests do not have a paper envelope and thus the comb is visible, in contrast to nests of hornets and yellowjackets.
This is an example of a group of insecticides known as "synthetic pyrethroids." They are based on the structure of a chemical compound found in certain plants (Chrysanthemum flowers). Permethrin has the capacity to kill certain insects and ticks on contact, but has very low toxicity to vertebrates, except for fish. Permethrin also can serve as a repellent when applied to clothes and other fabrics such as tents and sleeping bags.
This is a repellent that recently has been recommended by the Centers for Disease Control and Prevention (CDC) as an alternative to repellents containing DEET. Recent research has revealed that picaridin is repellent to mosquitoes, but less so than recommended concentrations of DEET.
No defintions for words starting with Q.
A host (or hosts) that harbors a disease agent and remains infected for extended periods of time. Reservoir hosts serve as a source of the disease agent to vectors, but usually are not adversely affected. Reservoir animals typically are vertebrates such as mammals and birds. However, certain mosquitoes and ticks also may be part of the reservoir of a particular disease agent if the agent passes from an infected female into her eggs and subsequently into later life cycle stages. (Note: refer to transovariole transmission and transstadial transmission for additional perspective on the concept of a reservoir.)
This is a group of bacteria that are intracellular parasites of cells lining the vascular system. Infections typically result in reddish, spotted rashes of the skin. For example, Rickettsia rickettsii, transmitted by ticks, is the cause of a disease known as "spotted fever."
The condition when a person is allergic to a specific allergen. It involves the attachment of specific IgE antibody to mast cells following an initial sting, or stings, by a species of social Hymenoptera, for example. A subsequent sting by the same or closely related species can result in the sensitized person having an allergic reaction.
A term applied to a disease condition(s) that persists in survivors of an acute infection. For example, sequelae associated with arboviral encephalitis can include paralysis, mental retardation, memory loss, and speech impediments. These conditions typically persist for the rest of the person's life.
This is a condition resulting from a sudden drop in blood pressure. In allergic reactions, shock is associated with increased vascular permeability caused by large amounts of histamine that has been released from mast cells.
A type of bee that exists in a colony consisting primarily of females known as "workers." Workers are females that possess a sting and respond to disturbances by stinging in defense of the colony. Venoms of social bees contain allergens, and people who are prone to allergies can become sensitized after they are stung. The most common social bee is the honey bee, Apis mellifera. Other social bees include bumble bees, a group consisting of numerous species in the genus Bombus, none of which are a serious medical risk.
A type of wasp that exists in a colony consisting primarily of females known as "workers." Workers are females that possess a sting and respond to disturbances by stinging in defense of the colony. Venoms of social wasps contain allergens, and people who are prone to allergies can become sensitized after they are stung. The most common social wasps are paper wasps in the genus Polistes, yellowjackets in the genus Vespula, and hornets in the genus Dolichovespula, all of which can be serious medical risks.
This is a type of bee that does not exist in a colony. Instead, the nest of a solitary bee is built and the larvae reared by a single female. Female solitary bees typically do not defend their nest, and sting only if mishandled. Venoms of solitary bees are not known to contain allergens and have not been associated with allergic reactions. The most common and familiar example of a solitary bee is the carpenter bee.
This is a type of wasp that does not exist in a colony. Instead, the nest of a solitary wasp is built and the larvae reared by a single female. Female solitary wasps typically do not defend their nest, and sting only if mishandled. Venoms of solitary wasps are not known to contain allergens and have not been associated with allergic reactions. There are numerous examples of solitary wasps, among the most common and familiar are the cicada killer, mud daubers, and spider wasps.
An important approach to the control of mosquito larvae that involves the elimination of aquatic habitats in which mosquito larvae develop, or at least their modification so as to reduce larval development. Another name for this approach is environmental control.
These are large, spiral-shape bacteria that are mobile, highly invasive, and capable of causing disease in vertebrates. For example, the causative agent of Lyme disease is a spirochete with the scientific name Borrelia burgdorferi.
This is the structure formed by a modified ovipositor on female ants (nearly all species), bees, and wasps through which venom is introduced during the act of stinging.
This is a physician prescribed device for individuals who have been sensitized to the venom of an ant, social bee, or social wasp. An "epi pen" contains a syringe pre-loaded with a dose of epinephrine, which should be injected immediately after a sting.
This is an allergic reaction that involves complications in regions of the body apart from the site of a sting. For example, when a sensitized person is stung on a finger and experiences a drop in blood pressure, constriction of airway passages, and extensive swelling in areas of the body in addition to swelling of the finger where the sting occurred.
A condition of paralysis that initially affects the lower legs, progresses upward in the body and eventually affects the muscles that regulate breathing. It is caused by a toxin in the saliva of a female tick that is attached and sucking blood near the spinal cord of a vertebrate animal. Recovery usually is complete after removal of the tick.
This is the passage of a disease agent from an infected female into her eggs. For example, LaCrosse Encephalitis virus can pass from an infected female tree hole mosquito into her eggs, inside of which the virus over-winters. Larvae developing from infected eggs the following summer may be infected with virus that then can undergo transstadial transmission.
This is the passage of a disease agent from an infected immature stage to the next immature stage or to the adult stage of an arthropod vector. For example, LaCrosse Encephalitis virus can pass through all four larval stages of a tree hole mosquito, from the last larval stage into the pupa, and from the pupa into the adult. Thus a female tree hole mosquito derived from an infected egg can be infected with LaCrosse Encephalitis virus without having taken a blood meal from an infected chipmunk or squirrel.
No defintions for words starting with U.
An infected arthropod that is capable of transmitting a disease-causing agent to a susceptible vertebrate host. For example, a female house mosquito can acquire West Nile Virus when feeding on an infected bird and subsequently pass the virus via saliva injected during the taking of a blood meal from a human or a horse.
A complex mixture of chemicals injected during the defensive sting of an ant (nearly all species), bee, or wasp. Venoms typically contain chemicals that cause immediate burning pain. In addition, venoms of social bees, social wasps, and a few species of ants are known to contain allergens that are involved in allergic reactions.
A member of the insect order Hymenoptera (ants, bees, and wasps), the larval stages of which are fed meat, typically spiders and other insects. This is in contrast to bees, the larval stages of which are feed pollen. The vast majority of species of wasps are solitary and of no medical risk. The most important exceptions include paper wasps, yellowjackets, and hornets, all of which are social species that possess venom associated with allergic reactions.
This is a name given to species of social wasps in the genus Vespula. Species of Vespula typically build their nests underground or inside other dark sites including wall voids, attics, and basements. Stings of certain species of Vespula, together with the honey bee, are the most important cause of allergic reactions.
This is a disease that occurs naturally in non-human vertebrate animals, but which can affect humans. For example, West Nile is a disease of birds with the virus transmitted among birds by Culex mosquitoes. Humans are considered incidental hosts and therefore not necessary for the existence and transmission of West Nile Virus, but humans can become infected with the virus and suffer pathology. The vast majority of vector-borne diseases are zoonoses.