2.5d,e,f Parasitism - Defence against parasitic attack, immune evasion and treatment and control Flashcards
What are some non-specific defenses in mammals?
Chemical secretions - stomach acid, tears
Inflammation - histamine causing vasodilation
Cellular - phagocytes, natural killer cells, interferon
Physical barriers - epithelial cells, hydrolytic enzymes, low pH environments
What is the role of the inflammatory response?
To increase blood flow to get more
What is the role of natural killer cells?
To make infected cells perform apoptosis
What are the roles of lymphocytes?
Some lymphocytes produce antibodies specific to a pathogen. Antibody-antigen complex deactivates the pathogen
Others can induce apoptosis in parasite infected cells
What is the role of antibodies?
to form the antibody-antigen complex to deactivate a pathogen
What is the role of memory lymphocytes?
makes second exposure to parasite faster and more abundant
What are ways in which parasites exhibit immune evasion?
antigenic variation
integrating its genome into the host’s genome
mimicking host antigens
What methods do parasites employ to maximise their success?
suppress the host immune system
modify host size
modify host reproductive rate
What are 3 routes of transmission for ecto and endoparasites?
Direct contact
Consumption of intermediate host
Vectors
What is epidemiology?
Epidemiology is the study of the outbreak and spread of infectious disease
What role does vaccines and herd immunity play in epidemiology?
Vaccines reduce the spread of a pathogen and once enough people have been vaccinated, the population will reach herd immunity which means there won’t be an outbreak of the disease
Define a retrovirus
RNA retroviruses use the enzyme reverse transcriptase to form DNA, which is then inserted into the genome of the host cell
What is a challenges to parasite treatment and control?
Parasites spreading rapidly due to overcrowding or tropical climates
What is apoptosis?
programmed cell death
What is a way of controlling transmission?
Civil engineering projects to improve sanitation combined with co-ordinated vector control
