Common Arthropod-borne Bacterial & Viral Diseases

Flashcards covering common arthropod-borne bacterial and viral diseases, their vectors, and associated symptoms.

Arthropod

Invertebrates with jointed legs, segmented bodies, and a hardened, chitinous exoskeleton that serve as vectors for many microbial diseases.

Mechanical Vector

Arthropod vector that picks up a pathogen on the outside of its body and carries it from one place to another.

Biological Vector

Arthropod vector where the pathogen enters the vector and multiplies inside.

Borrelia burgdorferi

Spirochete bacteria that causes Lyme Disease, transmitted by deer ticks and other ticks.

Erythema chronicum migrans

Rash associated with Lyme disease, characterized by a bull’s-eye appearance (concentric rings around initial site of tick bite).

Yersinia pestis

Gram-negative coccobacilli bacteria that causes Plague (Bubonic, Septicemic, Pneumonic), transmitted by flea bites.

Bubonic Plague

Form of plague characterized by swollen, painful lymph nodes (buboes).

Septicemic Plague

Form of plague where bacteria escapes from the infected bubo into the bloodstream, causing septicemia (bacteremia).

Pneumonic Plague

Form of plague resulting from a bacteremia that travels to the lungs, communicable via respiratory droplets. Characterized by a shorter incubation period and greater mortality (90%).

Francisella tularensis

Gram-negative bacilli, bacteria that causes Tularemia (Rabbit Fever, Lawnmower Disease), transmitted through breaks in skin, bite from arthropod biological vectors, inhalation of aerosols during skinning, consumption of contaminated meat.

Rickettsias

Obligate intracellular bacteria (once thought to be viruses); they cannot be grown in the lab on artificial media since they require cells to replicate.

Rocky Mountain Spotted Fever

Disease caused by Rickettsia rickettsii, transmitted by dog ticks; symptoms include fever, headache, weakness, and rash that begins on hands and feet and progresses toward trunk.

Endemic Typhus

Disease caused by Rickettsia typhi, transmitted by fleas; symptoms include fever, chills, headache, vomiting, and rash that starts on the trunk and spreads to extremities.

Epidemic Typhus

Disease caused by Rickettsia prowazekii, transmitted by body lice; symptoms include fever, headache, and rash that starts on the trunk and spreads to extremities.

Rickettsial Pox

Disease caused by Rickettsia akari, transmitted by mites found on house mice; symptoms include eschar at bite site and vesicular lesions.

Yellow Fever

Viral disease transmitted by mosquitoes; many victims suffer severe liver damage and become jaundiced.

Equine Encephalitis

Infection/inflammation of the CNS caused by EEE, WEE, VEE, and SLE viruses; transmitted by mosquitoes.

West Nile Virus

Viral disease spread by the bite of a mosquito; can infect people, horses, birds, and some other animals; can result in West Nile encephalitis.

Zika Virus

Viral disease transmitted by mosquitoes and horizontally (STD); symptoms include joint pain, muscle aches, conjunctivitis, headache, fever, maculopapular rash; teratogenic.

Dengue Fever

Viral disease transmitted by mosquitoes; symptoms include myalgia and arthralgia (severe joint pain), high fever, bleeding gums, vomiting, rash; can progress to Dengue Hemorrhagic Fever or Dengue Shock Syndrome.