Related Experiment Video
Updated: Jul 17, 2026
05:29
Propagation of the Microsporidian Parasite Edhazardia aedis in Aedes aegypti Mosquitoes
Published on: August 13, 2020
Interference and the persistence of vertically transmitted parasites.
1Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, England, UK. bop03eoj@sheffield.ac.uk
Journal of Theoretical Biology
|January 31, 2007
Summary
A virulent vertically transmitted parasite (VTP) can persist by protecting hosts from a horizontally transmitted parasite (HTP). This interaction can stabilize host population cycles, offering insights into disease persistence and biological control.
Area of Science:
- Ecology
- Epidemiology
- Evolutionary Biology
Background:
- Understanding the persistence of multiple natural enemies, especially vertically transmitted parasites (VTPs), is crucial.
- Vertically transmitted parasites (VTPs) coexist with hosts and other parasites, influencing ecological dynamics.
Purpose of the Study:
- To analyze a model where a virulent VTP persists alongside a host and a horizontally transmitted parasite (HTP).
- To investigate how VTPs protect hosts from HTPs through ecological interference and its impact on population dynamics.
Main Methods:
- Mathematical modeling of host-parasite interactions.
- Analysis of parasite persistence conditions based on transmission modes and host reproductive strategies.
Main Results:
- VTP persistence is favored when HTPs inhibit host reproduction, with VTPs providing protection via ecological interference.
- VTPs persist more readily in r-selected hosts and with highly transmissible HTPs.
- Increased protection by VTPs leads to higher host densities and stabilizes host population cycles.
Conclusions:
- Interactions between parasites can influence disease persistence and population stability.
- Vertically transmitted parasites (VTPs) can have stabilizing effects on host populations, with implications for biological control strategies.
Related Concept Videos
01:22Microbial Interactions: Parasitism
Parasitism is a form of microbial interaction in which parasitic microbes exploit a host organism for nutrients and shelter, often at the host's expense. Unlike mutualistic relationships, where both organisms benefit, parasitism benefits only the parasite and harms the host.Classification of ParasitesMicrobial parasites are broadly classified based on their location relative to the host.Ectoparasites remain on the host’s surface, such as the skin or outer tissues, drawing nutrients...
01:29Malaria
Malaria pathogenesis in humans reflects a delicate interplay between parasite biology and host response. Clinical illness reflects a host’s immune response to the parasite’s asexual replication cycle, which is often asymptomatic in individuals with partial immunity. From the parasite's perspective, transmission between mosquito and human with minimal host pathology is evolutionarily advantageous. Among the six Plasmodium species infecting humans, P. falciparum and P. vivax dominate in global...
01:27Diversity of Protists II
Alveolates are a group of organisms recognized by the presence of alveoli, which are cytoplasmic sacs located beneath the cell membrane. While their function remains uncertain, alveoli may help regulate water balance by controlling how much water enters and leaves the cell. In dinoflagellates, these structures may serve as armor plates. There are three major types of alveolates: ciliates, which move using cilia; dinoflagellates, which use flagella for movement; and apicomplexans, which are...
01:30Reservoir of Infection
Infectious diseases arise from intricate interactions between pathogens and their reservoirs. A reservoir of infection refers to the natural habitat where a pathogen lives, grows, and multiplies, serving as a continual source of infection. Reservoirs are broadly classified as either living or nonliving, and each plays a unique role in disease transmission, significantly influencing public health interventions and control strategies.Humans act as reservoirs for a wide array of pathogens,...
01:24Transmission of Pathogens
Pathogens spread from their reservoirs to susceptible hosts through three main routes: contact transmission, vehicle transmission, and vector transmission. Each route involves distinct mechanisms of transfer.Contact TransmissionThis category includes direct contact, indirect contact, and droplet transmission:Direct contact involves immediate physical interaction between individuals—such as a handshake—which can spread pathogens like Streptococcus pyogenes, the bacterium responsible for...
01:20Infection
When a pathogen enters the body and reproduces, it can cause an infection, damage body cells, and cause illness symptoms that eventually lead to disease. Therefore, its prevention requires breaking the chain of infection.
The chain begins with pathogens: bacteria, viruses, fungi, prions, or parasites such as protozoa helminths. These can be present on the skin as transient or resident flora, or they can be acquired from the environment. Identifying and treating the type of infection and...
The chain begins with pathogens: bacteria, viruses, fungi, prions, or parasites such as protozoa helminths. These can be present on the skin as transient or resident flora, or they can be acquired from the environment. Identifying and treating the type of infection and...