Example of metazoonotic infection
Reading File
Finding Sources
Searching the Web
metazoonotic infection definition examples
Finding Sources
Searching the Web
metazoonosis definition rabies WHO classification zoonoses types
This is an important clarification worth correcting from my initial quick answer. Let me break this down properly.
Metazoonosis (Pherozoonosis) - Definition & Examples
Metazoonosis (also called pherozoonosis) is a specific category within the epidemiological classification of zoonoses. The term is used in a precise way that is different from how I initially described it.
The 4 Epidemiological Categories of Zoonoses
| Category | Definition | Hosts Required |
|---|---|---|
| Orthozoonosis (Direct zoonosis) | Transmitted directly from infected vertebrate to susceptible vertebrate via direct contact, fomite, or mechanical vector | Single vertebrate species |
| Cyclozoonosis | Requires >1 vertebrate species to complete the infectious cycle | Multiple vertebrates, no invertebrate |
| Metazoonosis (Pherozoonosis) | Requires both a vertebrate AND an invertebrate host for cycle completion | Vertebrate + invertebrate |
| Saprozoonosis | Requires a vertebrate host AND a non-living environmental reservoir (soil, food, organic matter) | Vertebrate + inanimate reservoir |
Metazoonosis - Key Feature
In metazoonoses, the infectious agent multiplies or develops within the invertebrate (arthropod vector), and there is always an extrinsic incubation period in the invertebrate before transmission back to a vertebrate host.
Examples of Metazoonosis
| Disease | Pathogen | Vertebrate Reservoir | Invertebrate Vector |
|---|---|---|---|
| Arbovirus infections (e.g., Yellow fever, Dengue, West Nile fever) | Flaviviruses, Togaviruses | Humans, monkeys, birds | Mosquitoes (Aedes, Culex) |
| Plague | Yersinia pestis | Rodents (rats, prairie dogs) | Fleas (Xenopsylla cheopis) |
| Lyme borreliosis | Borrelia burgdorferi | Small mammals, deer, birds | Ticks (Ixodes spp.) |
| Rickettsial infections (e.g., Rocky Mountain spotted fever, typhus) | Rickettsia spp. | Rodents, rabbits | Ticks, lice, fleas |
| Leishmaniasis | Leishmania spp. | Dogs, rodents, humans | Sandflies (Phlebotomus, Lutzomyia) |
| Malaria (some forms) | Plasmodium spp. | Humans, primates | Mosquitoes (Anopheles) |
Correction of Initial Answer
My quick answer cited rabies as the example - that was incorrect. Rabies is actually an orthozoonosis (direct zoonosis) because it is transmitted directly between vertebrates (dog bite to human) without requiring an invertebrate. The classic and most-cited example of a metazoonosis is plague or arboviral infections such as yellow fever, where an arthropod (flea or mosquito) is an obligatory part of the life cycle.
This is a shared conversation. Sign in to Orris to start your own chat.