PARA L1

• PARASITOLOGY

  • Area of biology concerned with the phenomenon of dependence of one living organism on another
  • Study of parasites, their hosts and the relationship between them.
• BRANCHES OF PARASITOLOGY

  1. Medical Parasitology2. Veterinary Parasitology 3. Structural Parasitology 4. Quantitative Parasitology

  5. Parasite Ecology6. Conservative Biology of Parasite7. Taxonomy & Phylogenetics
• Medical Parasitology • Concerned primarily with parasites of humans and their medical significance as well as their importance in human communities
• VETERINARY PARASITOLOGY

  • Study of animal parasites, especially relationships between parasites and animal hosts that includes domestic animals, (livestock and pet animals), as well as wildlife animals
• STRUCTURAL PARASITOLOGY

  • Study of structures of parasitic proteins. It involves protein expression, protein purification and crystallography
  • Done in research laboratories. Found in Manila - RITM (Research Institute of Tropical Medicine)
• QUANTITATIVE PARASITOLOGY • Scientific study of quantifying parasites in a sample of hosts or comparing measures of infection across two or more samples
• PARASITE ECOLOGY

  • Study of parasites on their interactions with their hosts and environment as well as their life cycles
• Conservation Biology of Parasite deals with the study of parasite conservation specially those living in the wilds and harmless to humans and domesticated animals that includes captive breeding and reintroduction program
• TAXONOMY & PHYLOGENETICS

  • Study of classification, identification, naming of parasites according to the evolutionary relationship and through molecular sequencing & morphological data matrices
  • Done in research laboratories.
• SYMBIOSIS:

  • “Living together of two unlike organisms”
  • It refers to living together in more or less intimate association or close union of two dissimilar organisms and may involve protection or other advantages to one orboth partners
• Types of Symbiotic Associations: Phoresis and Commensalism
• PHORESIS (Phoresy)

  • Phoresis means “to carry”
  • A type of symbiotic relationship in which one organism (phoront) is mechanically carried on or in another species (host)
• phoront - one being carried

  host - one carrying
• COMMENSALISM

  • Means “eating at the same table”
  • Occurs when one member of the associating pair,usually the smaller, receives all the benefit and theother member is neither benefited nor harmed. Example: Entamoeba coli: resides in the human intestinal lumen. They are supplied with nutrients and/or protected from harm, while it does not cause any damage to the tissues of its hosts
  •  
• specialized type of commensalism: Mutualism and Parasitism
• MUTUALISM• Symbiosis in which two organisms mutually benefit from each other• Occurs when each member of the association benefits the other• Mutuals are metabolically dependent on one another (beneficial to both); one cannot survive in the absence of the other• Example: Termites & Flagellates in their digestive system Flagellates: synthesize the enzyme “cellulase”, which aids in the breakdown of ingested wood
• PARASITISM:• Symbiotic relationship where one organism - the

  parasite - lives in or on the other, depending on the host for its survival and usually at the expense of the host.

  • Symbiotic relationship in which one organism, the host isto some degree injured through the activities of the other
  • Example of parasite: Entamoeba Histolytica - derives nutrition from the human host and causes amoebicdysentery
• • Parasitos (from. Greek word: “para” meaning beside &“sitos” meaning grain or food)
• PARASITE

  • An organism that lives on or in their host, which is usually a larger organism, that provide physical protection and nourishment
  • Has sustained contact with another organism to the detriment of the host organism
  • A parasite may live on or in the host
• TYPES OF PARASITES ACCORDING TO HABITAT:

  1. Endoparasite
  2. Ectoparasite
• Endoparasite

  • A parasite that lives inside the body of a host
  • The presence of an endoparasite in the host is calledan “infection”
• Ectoparasite

  • Parasite living outside the body of the host
  • The presence of an ectoparasite in a host is calledan “infestation”
• TYPES OF PARASITES ACCORDING TO METABOLIC DEPENDENCY: Obligate Parasite and Facultative Parasite
• Obligate Parasite

  • Most parasites are obligate parasites. In that, they need a host at some stage in their life cycle to complete their development and to propagate their species
  • Cannot exist without a host, needed to complete their development and propagate their specieso Example: Tapeworms - depend entirely on their host for existence
• Facultative Parasite

  • ▪  May exist in a free-living state or parasitic when the need arises
  • ▪  Example:Schistosoma,Amoeba
• Kinds of Facultative Parasite: Amphizoic and Spurios
• Amphizoic

  • free living amoeba that may invade and colonize the brain and other site
  • Example: Naegleria, Acanthomoeba
• Spurios

  • free-living parasites or organisms that parasitize other hosts, they merely pass the intestine, recovered in living or dead state from the human feces
  • Visits only and does not stay in the body
  • Example: Ascaris, Flukes, Endolimax nana
• • Predator - those that attacks another living animal or organism not necessarily killing them (Attacker)
• • Prey - they are the victim (Being Attacked)
• • Scavenger - devouring those dead of natural causes ortaking the living of the predator
• HOST is the organism from which a parasite obtains its nutrition and/or shelter
• TYPES OF HOSTS BASED ON THE ROLE IN THE LIFE CYCLE OF THE PARASITE:

  Definitive/Final Host

  Intermediate Host

  Reservoir Host

  Paratenic Host
• Definitive/Final Host

  • Parasite attains sexual maturity
  • host which the sexual reproduction of parasite takesplace Example: Taeniasis - humans are considered the definitive host
• Intermediate Host • Harbors the asexual or larval stage of the parasite 

  Example

  1.  Pigs & Cattles - serve as an intermediate host for taenia species
  2.  Schistosoma species - their intermediate hosts are snails
• Intermediate host comes before the definitive/final host
• Reservoir Host

  • is an organism in which a parasite that is pathogenic for some other species, lives and multiplies in that organism usually without damaging its host

  • Allows the parasite’s life cycle to continue and become additional sources for human infections

  • Example:o Pigs - reservoirs of Balantidium colio Rats - reservoirs of Paragonimus

  westermani

  o Cats - can be reservoirs of the parasite Brugia malayi
• Reservoir Host - multiply w/o damage
• Paratenic Host

  • one in which the parasite does not develop further to the later stages; however, the parasite remains alive and is able to infect another susceptible host.
  • Example: Paragonimus metacercariae in raw boar meat can pass through the intestinal wall of humans and complete its development. In this case, the wild boar serves as the paratenic host transferring the infective stage to humans
  • Paratenic Host are quite important because they widen the parasite distribution and bridges the ecological gap between the definitive and intermediate hosts
• Paratenic Host - does not divide, does not damage