News tagged with parasites

Related topics: malaria , mosquitoes , red blood cells , malaria parasite , immune system

New malaria vaccine candidates identified

Researchers have discovered new vaccine targets that could help in the battle against malaria. Taking a new, large-scale approach to this search, researchers tested a library of proteins from the Plasmodium fa ...

19 hours ago
popularity not rated yet | comments 0

One route to malaria drug resistance found

Researchers have uncovered a way the malaria parasite becomes resistant to an investigational drug. The discovery, at Washington University School of Medicine in St. Louis, also is relevant for other infectious ...

Jul 24, 2014
popularity 5 / 5 (3) | comments 0

Parasitism

Parasitism is a type of symbiotic relationship between two different organisms where one organism, the parasite, takes favor from the host, sometimes for a prolonged time. In general, parasites are much smaller than their hosts, show a high degree of specialization for their mode of life, and reproduce more quickly and in greater numbers than their hosts. Classic examples of parasitism include interactions between vertebrate hosts and diverse animals such as tapeworms, flukes, the Plasmodium species, and scabs. Parasitism is differentiated from parasitoidism, a relationship in which the host is always killed by the parasite such as moths, butterflies, ants, flies and others.

The harm and benefit in parasitic interactions concern the biological fitness of the organisms involved. Parasites reduce host fitness in many ways, ranging from general or specialized pathology (such as castration), impairment of secondary sex characteristics, to the modification of host behaviour. Parasites increase their fitness by exploiting hosts for food, habitat and dispersal.

Although the concept of parasitism applies unambiguously to many cases in nature, it is best considered part of a continuum of types of interactions between species, rather than an exclusive category. Particular interactions between species may satisfy some but not all parts of the definition. In many cases, it is difficult to demonstrate that the host is harmed. In others, there may be no apparent specialization on the part of the parasite, or the interaction between the organisms may be short-lived. In medicine, only eukaryotic organisms are considered parasites, with the exclusion of bacteria and viruses. Some branches of biology, however, regard members of these groups as parasitic.[citation needed]

This text uses material from Wikipedia licensed under CC BY-SA