Definitions
Virulence factors
Traits of pathogens that enhance their ability to cause disease, such as toxins or mechanisms to evade the immune system.
The newest and smallest class of pathogen
Prions
Transmission is the way a pathogen spreads disease from one host to the next, It can be either ....
direct or indirect
This French scientist is known for developing a heat treatment process, which is named after him, used to kill microbes in milk.
Pasteur
Differentiate between infectious and non infectious diseases
Infectious - caused by pathogens
Non infectious - these are caused by genetics, environmental influences or cellular malfunction
Organisms that can only reproduce within a host cell.
Obligate Intracellular Parasites
reproduce by an asexual process known as binary fission
bacteria
What is the difference between
Active carriers and passive carriers
This physician is credited with identifying the bacterium that causes the disease tuberculosis.
Koch
Who is John Snow?
best known for his investigation into the 1854 cholera outbreak in Soho, London.
Father of modern epidemiology
Diseases transmitted from animals to humans
zoonoses
cause disease do so by producing toxins or chemicals that are harmful to the host’s body, or by damaging host tissue directly
bacteria
A rare bacterial illness initially spreads among staff when an infected worker preparing meals cuts their hand and bleeds onto the ready-to-eat salad, which is then consumed by multiple guests
indirect
This scientist performed the definitive experiment using swan-neck flasks to finally disprove the theory of spontaneous generation
pasteur
Case Study: Panama Disease in Bananas
Name the pathogen that caused this fungus Fusarium oxysporum
Exotic diseases
(introduced) diseases
range in size from 1 to 300μm.
protozoa
Health officials notice a new spike in cases. They find the bacterium is now being passed from person to person when ill guests cough directly into the face of healthy employees during check-in/check-out interactions.
direct
This scientist is famous for devising a set of four experimental steps, known as postulates, used to prove that a specific microorganism causes a specific disease.
Koch
Give an adaptation of a named pathogen to gain entry
The misfolded prion protein (PrPSC) binds to the surface of a neuron (nerve cell), resulting in neuron synapse degradation and eventually cell death.,They are resistant to being denatured by high temps, high pressure, digestion by lysosomes and toxic chemicals
Generally, virus makes contact with host cell’s surface, the virus’ proteins will bind to a surface receptor, transported through membrane, virus releases its genetic information.
Bacteria - Various methods, they can invade the cell membrane using pili or fimbriae which bind to the host cells surface. They then secrete toxins to break down connective tissue between cells on cell membrane allowing bacteria to pass through the cell membrane. For e.g., Staphylyococcous aureus
On the surface of protozoan’s apex, there are receptors that can bind with host cell’s surface or cell membrane. They then invade the cell membrane by corkscrewing itself through the cell membrane.
When a fungal spore germinates, hyphae can be released from the spore and it penetrates the host cell’s membrane. The hyphae can also secrete necrotic factors which are enzymes that can break down a portion of the cell membrane.
E.g. the Australian paralysis tick can inject their mouth through the cell membrane and secrete saliva and neurotoxins into the cytoplasm. The saliva stops the inflammation response by the host. The toxin can cause temporary paralysis, heart problems or failure.
Retrovirus
Viruses that contain RNA
Giardia lamblia is a common pathogenic .....
protozoa
There are 3 things that are required for infection to occur.. what are they
A host that is susceptible to the disease
A pathogen that is capable of causing the disease
3. A mode of transmission- a way for the pathogen to get from host to host.
What are Kochs 4 postulates?
The microorganism must be present in the tissues of the infected organism and not in a healthy organism.
The microorganism must be able to be cultivated in isolation from the infected organism.
When an uninfected organism is then inoculated with the culture, it should develop symptoms of the disease.
Samples from the second infected organism should be able to be isolated and found to be the same as the microorganism from the first infected organism.
transmission of a disease during an epidemic: Malaria Case Study
How did they prevent and reduce malaria transmission
insecticide-treated mosquito nets and indoor residual spraying.