Module Identifier BS31820  
Module Title PARASITOLOGY  
Academic Year 2001/2002  
Co-ordinator Professor John Barrett  
Semester Semester 1  
Other staff Dr Conor Caffrey, Dr Peter Brophy  
Course delivery Lecture   30 Hours  
  Practical   9 Hours 3 x 3 hours. 1 x 1 hour seminar/tutorial  
Assessment Practical exercise   consisting of 3 practical write ups to be handed in one week after each practical session, weeks 4, 5 and 6.   30%  
  Exam   3 Hours One 3-hour theory paper   70%  
  Resit assessment   3 Hours One 3-hour theory paper. (plus re-submission of failed coursework or an alternative)   70%  

Aims and objectives


The nature of parasitism will be discussed using examples from the major protozoan and helminth groups. The course will emphasise the dynamic nature of the relationship between parasites and their hosts and seeks to present an overview of current research on the organisms that live in the third great environment - namely the body of another individual.

Content


The module will cover the basic morphology, physiology and life cycles of the major groups of parasitic protozoans, monogeneans, digeneans, cestodes, acanthocephalans nematodes, (plant and animal parasitic) and parasitic arthropods, with special reference to those of medical or economic importance.
Sites of parasitism will be illustrated by a consideration of the vertebrate gut and how parasites are adapted for life in this specialized environment. There is a complex interaction between parasites and the immune systems of their hosts. Parasites have evolved a range of evasion strategies, including absorption of host antigen, antigenic variation, immuno-suppression and use of immunologically privileged sites. Immune evasion will be illustrated with examples from vertebrate and invertebrate hosts. Chemotherapy is still the most cost effective way of treating parasitic disease, but drug resistance is an increasing problem.
Parasites show a wide range of biochemical adaptations, many related to the microaerobic nature of their environment and the changes that occur during their life cycle. Biochemical differences between parasites and their hosts provide targets for rational chemotherapy, whilst differences between parasites and their free-living relatives can give an insight into the biochemical basis of parasitism. The organization of parasite genomes and some of the unique mechanisms of mRNA editing found in parasites will also be covered.
The discovery, development and mode of action of modern antiparasite drugs will be described, as will the mechanisms responsible for the evolution of drug resistance. The helminth nervous system is structurally simple, but biochemically complex and is another important target for anthelmintics.
The many problems involved in making a realistic assessment of the cost of parasitism or of measuring the impact of parasites on their natural hosts, will be discussed. Frequent attempts have been made to control parasites of humans, domesticated livestock and crops; the outcome of some of these control strategies will be evaluated. A summary of the current ideas on the evolution of parasites, the impact of parasites on the evolution of their hosts and of the concept of host-parasite specificity will be presented and discussed. The structure of parasites will be discussed in relation to the insight these studies provide into parasite survival both within the host and during the free-living stages. Life cycles, development and modes of transmission will include accounts of the importance of direct transmission, the role of vectors and intermediate hosts, zoonoses and reproductive potential (Ro). Patterns in the distribution of parasites will be described and the mechanisms responsible for generating those patterns evaluated. This will lead to a consideration of mathematical models and their use in predicting parasitic disease.
The module will include a seminar discussion on a recent research publication that will form the basis of a compulsory question in the written examination.
A full synopsis of the lecture course is available on http:/www.aber.ac.uk/~mpgwww

Learning outcomes


On completion of the module the student
? will have an awareness of the diversity of parasites (as expressed in their structure, physiology, life cycles and development) and their potential to cause disease and economic loss
? be aware of attempts and strategies to control parasites
? will have an insight into recent developments in parasite molecular biology.

Reading Lists

Books
** Recommended Text
Smyth, J.D.. (1994) Introdcution to animal parasitology. Cambridge University Press.
Cox, F.E.G.. (1993) Modern Parasitology. 2nd. Oxford.