ACE Environmental & Public Health 3 — Questions and Answers
Question 1: A public health entomologist is evaluating a neighborhood with high rates of Lyme disease. Which landscape feature should be prioritized for tick management?
- Open sunny lawns
- Leaf litter accumulation at forest-lawn interfaces (Correct answer)
- Paved driveways
- Ornamental flower beds
Correct answer: Leaf litter accumulation at forest-lawn interfaces
Leaf litter at forest-lawn edges provides the moist, shaded microhabitat that Ixodes scapularis nymphs require for survival.
Question 2: Which factor makes Culex quinquefasciatus a significant public health concern in urban areas of the southern United States?
- It bites only during daylight hours
- It serves as the primary vector of West Nile virus and breeds in polluted water (Correct answer)
- It can survive at near-freezing temperatures
- It transmits malaria in Gulf Coast states
Correct answer: It serves as the primary vector of West Nile virus and breeds in polluted water
Culex quinquefasciatus is the primary urban West Nile virus vector and thrives in stagnant, nutrient-rich water common in cities.
Question 3: What is the significance of the 'synanthropic' classification for certain fly species in public health entomology?
- They are found only in wilderness areas
- They live in close association with humans and can transmit pathogens (Correct answer)
- They are exclusively nocturnal feeders
- They are resistant to all chemical controls
Correct answer: They live in close association with humans and can transmit pathogens
Synanthropic flies like house flies live near human habitation, feed on waste and food, and mechanically transmit enteric pathogens.
Question 4: An entomologist discovers high densities of Simulium (black fly) larvae in a fast-flowing river. What is the most likely public health concern in this region?
- Dengue fever transmission
- Onchocerciasis (river blindness) risk, particularly in endemic regions (Correct answer)
- Malaria transmission
- Leishmaniasis risk
Correct answer: Onchocerciasis (river blindness) risk, particularly in endemic regions
Black flies of the genus Simulium are the primary vectors of Onchocerca volvulus, which causes river blindness in endemic tropical areas.
Question 5: Which method is used to determine whether a pesticide application near a sensitive ecosystem complies with the Endangered Species Act?
- MSDS sheet review
- Pesticide use limitation consultation via EPA's ESA pesticide workplan (Correct answer)
- Soil pH testing
- Crop rotation scheduling
Correct answer: Pesticide use limitation consultation via EPA's ESA pesticide workplan
The EPA's ESA workplan establishes mitigation measures to protect listed species and their critical habitats from pesticide exposure.
Question 6: A vector control district is considering using Bacillus thuringiensis israelensis (Bti) for mosquito control. What is the primary environmental advantage of this approach?
- It persists in the environment for months, reducing reapplication needs
- It is highly selective for mosquito and black fly larvae with minimal non-target impact (Correct answer)
- It controls adult mosquitoes effectively
- It eliminates all aquatic insects in treated water
Correct answer: It is highly selective for mosquito and black fly larvae with minimal non-target impact
Bti targets only mosquito and black fly larvae via specific gut receptors, making it environmentally selective with negligible impact on non-target organisms.
Question 7: Which human behavioral factor most significantly amplifies the risk of flea-borne typhus transmission in urban settings?
- Outdoor recreation in forested areas
- Proximity to feral cat and opossum populations harboring infected fleas (Correct answer)
- Swimming in natural water bodies
- Consumption of undercooked meat
Correct answer: Proximity to feral cat and opossum populations harboring infected fleas
Feral cats and opossums are reservoir hosts for Rickettsia typhi, and their fleas readily feed on humans living nearby in urban environments.
ACE Environmental & Public Health 3
A public health entomologist is evaluating a neighborhood with high rates of Lyme disease.
Which landscape feature should be prioritized for tick management?