Zoonotic & Vector-borne Diseases Overview

Vocabulary flashcards summarizing causative agent, reservoir, transmission route, and hallmark clinical features for major zoonotic and vector-borne diseases discussed in the lecture.

Arboviral Encephalitides (WNV, WEE, SLE)

Mosquito-borne viruses maintained in wild birds; Culex tarsalis bites transmit to humans causing mild flu-like illness that can progress to severe neurological disease, coma, or death.

Chagas Disease

Protozoan Trypanosoma cruzi carried by opossums and woodrats; reduviid (kissing) bugs defecate during feeding, parasites enter skin when scratched; ranges from asymptomatic to acute fever, malaise, eyelid edema, and lymphadenopathy.

Cryptococcosis

Fungus Cryptococcus neoformans grows in pigeon droppings; inhalation of contaminated dust leads to pulmonary infection and potentially fatal meningitis or systemic disease (skin, bone, kidneys).

Hantavirus Pulmonary Syndrome

Sin Nombre virus shed by deer mice; inhalation of aerosolized urine or feces causes 1–2 week flu-like prodrome that rapidly progresses to severe respiratory distress; ~40 % fatality.

Histoplasmosis

Fungus Histoplasma capsulatum found in soil enriched with bat or bird guano; inhaled spores cause asymptomatic infection or acute respiratory disease that may disseminate to liver, spleen, kidneys—mimicking tuberculosis.

Leptospirosis

Over 200 Leptospira serovars harbored by wild & domestic mammals; entry through abraded skin or mucous membranes via urine-contaminated water; presents with fever, chills, myalgia and may involve meningitis or encephalitis.

Lyme Disease

Spirochete Borrelia burgdorferi cycles in wild rodents and deer; transmitted by Ixodes (black-legged) ticks; early expanding erythema migrans rash, flu-like symptoms; untreated cases progress to arthritis and neurologic disorders.

Lymphocytic Choriomeningitis (LCM)

LCM arenavirus carried by house mice; exposure to aerosolized or food-borne urine/feces leads to fever, headache, myalgia, possible meningitis; deaths are rare.

Murine Typhus

Rickettsia typhi maintained in commensal rodents and opossums; fleas transmit via bites or feces; causes fever, headache, myalgia, trunk-centered rash; <1 % fatality.

Psittacosis (Ornithosis)

Chlamydophila psittaci infection from parrots, parakeets, and other birds; inhalation or handling of contaminated feces/secretions leads to fever, headache, chills, and atypical pneumonia with chest pain.

Plague

Yersinia pestis circulates among wild rodents; infected flea bites, contact with tissues, or inhalation of droplets cause bubonic, septicemic, or pneumonic plague marked by painful lymphadenopathy and high mortality if untreated.

Rabies

Lyssavirus spread by bites or saliva of bats, skunks, and other mammals; after 3–12 week incubation, fever and malaise progress to encephalitis, paralysis, and death within days of symptom onset.

Rat-bite Fever

Streptobacillus moniliformis from rat saliva or urine; bite or exposure leads to fever, chills, rash, arthralgia, and potential endocarditis or meningitis.

Rickettsialpox

Rickettsia akari transmitted by mite bites from house mice; local eschar followed by generalized vesicular rash sparing palms/soles and regional lymphadenopathy.

Rocky Mountain Spotted Fever

Rickettsia rickettsii maintained in ticks and wild rodents; tick bite causes high fever, headache, myalgia, and petechial rash (trunk → extremities); untreated fatality up to 80 %.

Salmonellosis

Numerous Salmonella enterica serovars from contaminated food/water or reptile pets; sudden onset diarrhea, abdominal pain, fever, nausea, and headache.

Tick-borne Relapsing Fever

Borrelia hermsii carried by rodents and transmitted by soft (Ornithodoros) ticks; recurring high fevers (up to 106 °F) separated by afebrile periods.

Tularemia

Francisella tularensis infection from rabbits or rodents via handling, ingestion, inhalation, or tick bite; causes ulceroglandular lesions, painful lymphadenopathy, pneumonia, or typhoidal illness.