Examples to Know (Viruses, Bacteria, Protozoa, Parasites, Vector-borne, Life-cycles, Transmission, Plant pathoge, etc)

What is an example of a virus causing disease in humans?

Poliovirus, which causes poliomyelitis.

What is an example of a virus causing disease in wildlife?

Canine distemper virus (CDV), which has caused severe epidemics in wildlife such as lions and African wild dogs.

What are examples of viruses mentioned in the lectures?

Poliovirus, canine distemper virus (CDV), phocine distemper virus (PDV), rinderpest virus, rabies virus, tobacco mosaic virus, dengue virus, yellow fever virus, and H5N1.

What is rabies an example of?

A viral disease transmitted through secretions/excretions, especially saliva.

What is tobacco mosaic virus an example of?

A virus transmitted through skin-to-skin/contact transmission in plants.

What is H5N1 an example of?

An emerging viral infectious disease mentioned in the lecture.

What is rinderpest an example of?

A viral disease of cattle and other susceptible animals that was targeted for eradication through vaccination.

What are bacteria?

Unicellular prokaryotes that can be intracellular or extracellular and may be parasitic, commensal, mutualistic, or free-living.

What is Yersinia pestis an example of?

A bacterium that causes plague, including bubonic and pneumonic plague.

What is Vibrio cholerae an example of?

A bacterium that causes cholera and can use environmental/waterborne and fecal-oral transmission.

What is Mycobacterium tuberculosis an example of?

A bacterium that causes tuberculosis.

What is Salmonella typhi an example of?

A bacterium that causes typhoid fever.

What is Treponema pertenue an example of?

A bacterium listed in the lecture as causing a bacterial sexually transmitted disease.

What is Neisseria gonorrhoeae an example of?

A bacterium that causes gonorrhea.

What is Chlamydia trachomatis an example of?

A bacterium that causes chlamydia.

What is Clostridium tetani an example of?

An opportunistic soil-dwelling bacterium that can cause tetanus after entering wounds.

What is Bacillus anthracis an example of?

A bacterium that causes anthrax and produces resistant spores that can persist in the environment.

What is Staphylococcus aureus an example of?

A bacterium that can be commensal under some conditions but can cause disease under others.

What is Streptococcus pneumoniae an example of?

A bacterium that can be part of normal microbial communities but can cause disease under some conditions.

What is Haemophilus influenzae an example of?

A bacterium that can be commensal but can also cause disease.

What are protozoa?

Single-celled eukaryotes that are extremely diverse and can be obligate or facultative parasites.

What is Giardia an example of?

An intestinal protozoan parasite transmitted through water.

What is an example of a blood protozoan transmitted by vectors?

The lecture describes blood protozoa generally as being transmitted by biting arthropods.

What makes protozoa different from bacteria?

Protozoa are eukaryotes, while bacteria are prokaryotes.

How do protozoa generally behave in disease models?

They typically behave more like microparasites.

What are the major helminth groups discussed in the lecture?

Nematodes, trematodes, monogeneans, cestodes, and acanthocephalans.

What are nematodes?

Roundworms.

What is Ascaris lumbricoides an example of?

A nematode (roundworm) and major human intestinal parasite.

What is special about Ascaris lumbricoides?

It is a giant roundworm that lives in the intestinal lumen and produces enormous numbers of eggs.

What are examples of Ascaris species in nonhuman hosts?

Ascaris suum in pigs, Parascaris equorum in horses/equids, Toxascaris leonina in dogs/cats, and Baylisascaris procyonis in raccoons/dogs.

What are trematodes?

Flukes or flatworms.

What is Schistosoma an example of?

A trematode (blood fluke) with a complex life cycle involving snails and vertebrate hosts.

What makes trematodes distinctive?

They commonly have complex life cycles and use two suckers to attach to hosts.

What are monogeneans?

Flatworm parasites that are primarily ectoparasites of fish and commonly attach using hooks or clamps.

What is a cestode?

A tapeworm.

What are Taenia saginata and Taenia solium examples of?

Tapeworms that infect humans and livestock.

How are Taenia tapeworms commonly transmitted according to the lecture?

Through infected pork or beef.

What is distinctive about an adult tapeworm?

It lacks a gut and absorbs nutrients across its surface.

What are the major structures of an adult tapeworm?

A scolex and proglottids.

What does the scolex do?

It attaches the tapeworm to the host's intestine.

What is a proglottid?

A segment of a tapeworm containing reproductive organs.

What is an acanthocephalan?

A thorny-headed worm that uses a thorny proboscis to attach to the host's gut wall.

What is Prosthenorchis an example of?

An acanthocephalan parasite.

What is Cordyceps an example of?

A parasitic fungus.

What are parasitic arthropods?

Macroparasites that include groups such as ticks, mites, lice, fleas, and bot flies.

What are examples of parasitic arthropods?

Ticks, mites, lice, fleas, lung mites, and bot flies.

What are examples of parasitic fungi?

Trichophyton spp. and Microsporum canis.

What disease is caused by fungi such as Trichophyton?

Ringworm.

Why are macroparasites not necessarily worms?

Macroparasites include worms, arthropods, and some fungi.

What is malaria an example of?

A vector-borne disease transmitted by mosquitoes.

What is dengue an example of?

A vector-borne viral disease.

What is yellow fever an example of?

A vector-borne viral disease.

What is Lyme disease an example of?

A vector-borne bacterial disease transmitted by ticks.

What bacterium causes Lyme disease?

Borrelia burgdorferi.

What vector transmits Borrelia burgdorferi?

The black-legged tick, Ixodes scapularis.

What is Ixodes scapularis an example of?

A vector that transmits a bacterial pathogen causing Lyme disease.

What are aphids examples of?

Plant-pathogen vectors that transmit about one-quarter of known plant viruses.

What do aphids transmit?

Many plant viruses.

What are leafhoppers examples of?

Plant vectors that transmit some viruses and bacteria.

What are whiteflies examples of?

Plant vectors that transmit DNA viruses.

What are mosquitoes examples of?

Vectors with free-living aquatic stages; adult females feed on nectar and blood.

What is a major example of vector control?

Using insecticidal bednets to reduce malaria transmission.

What is DDT an example of?

An insecticide historically used for vector control.

What evolutionary problem can repeated insecticide use create?

Selection for insecticide resistance in vector populations.

Why are vectors not the same as intermediate hosts?

Vectors transmit pathogens between hosts, whereas intermediate hosts support a parasite life stage in a complex life cycle.

What is a simple/monoxenic life cycle?

A life cycle that can be completed using one host species.

What is a complex/heteroxenic life cycle?

A life cycle requiring two or more host species to complete development and reproduction.

What is an example of a parasite with a complex life cycle involving snails and humans?

Schistosomes (Schistosoma).

What role do snails play in the Schistosoma life cycle?

They serve as hosts for an asexual stage.

What role do vertebrates play in the Schistosoma life cycle?

They serve as hosts for the sexual stage.

What is an example of a parasite with a complex life cycle involving a crustacean and fish?

Schistocephalus solidus.

What is Schistocephalus solidus?

A tapeworm that uses a cyclopoid copepod and three-spined stickleback before reaching its definitive fish-eating bird host.

What is the definitive host of Schistocephalus solidus?

A fish-eating bird.

What is an intermediate host of Schistocephalus solidus?

The three-spined stickleback is an intermediate host.

What is a direct-life-cycle example?

Geohelminths.

Why does a complex life cycle make transmission more complicated?

The parasite must successfully move through multiple hosts or life stages.

What is Toxoplasma gondii an example of?

A parasite with trophic transmission involving cats as the definitive host and rodents as an intermediate host.

How does Toxoplasma gondii demonstrate behavioral manipulation?

It alters infected rodent behavior in ways thought to increase the chance that rodents are preyed upon by cats.

Why would Toxoplasma benefit from rodents being eaten by cats?

Cats are the parasite's definitive host, so predation allows the parasite to reach the host where sexual reproduction occurs.

What is Leucochloridium paradoxum an example of?

A parasite involved in trophic transmission and behavioral manipulation of an intermediate host.

What does trophic transmission depend on?

Predator-prey interactions.

What must happen for a trophically transmitted parasite to reach its next host?

The infected host must be eaten by the appropriate later-stage host.

What is Dicrocoelium dendriticum an example of?

A parasite with trophic transmission and host manipulation.

What is Myrmeconema neotropicum an example of?

A parasite that manipulates its host in association with trophic transmission.

What is Schistocephalus solidus an example of?

A parasite with a complex trophic life cycle involving copepods, fish, and fish-eating birds.

What makes trophic transmission different from vector transmission?

Trophic transmission depends on one host being eaten by another, while vector transmission depends on another organism transferring the pathogen between hosts.

What is anthrax an example of?

An environmentally transmitted bacterial disease involving persistent spores.

What organism causes anthrax?

Bacillus anthracis.

Why is anthrax an important example of environmental transmission?

Bacillus anthracis produces resistant spores that can remain infectious in the environment for extremely long periods.

What is cholera an example of?

A disease involving environmental/waterborne transmission as well as fecal-oral human-to-human transmission.

What organism causes cholera?

Vibrio cholerae.

What is Giardia an example of in terms of transmission?

A water-transmitted intestinal protozoan parasite.

What are geohelminths examples of?

Parasites that can involve environmental transmission.

What is a fomite?

An inanimate object through which a pathogen can survive and be transmitted.

What are examples of fomites from the lecture?

A perch, salt lick, or food.

What makes anthrax especially suited to environmental persistence?

Its bacterium produces resistant spores.

What makes cholera different from anthrax in environmental transmission?

Cholera involves an environmental reservoir associated with water, while anthrax can persist in the environment as resistant spores.

What is tobacco mosaic virus an example of?

A plant virus transmitted through contact.

What are aphids an example of?

Vectors of plant viruses.

What are leafhoppers an example of?

Vectors that transmit some plant viruses and bacteria.