Lecture 1 Intro Flashcards
How much of earths biomass is microorganisms and what percentage is pathogenic to humans
60% and 0.5%
How can microorganisms be grouped by the pathogenicity
Saprophytes
Commensals
Opportunistic pathogens
True pathogens
Name an example of a commensals of URT
Candida albicans
Name 3 examples of opportunistic pathogens
Staphylococcus epidermidis (device related) Candida albicans (thrush) Ecoli (UTI)
How does s. Epidermidis stop pathogenic bacteria colonising skin
Produce fatty acids
In every gram of faeces how many ecoli are there
10^11
How can broad spectrum antibiotics cause thrush
Kill bacteria and allow yeast to grow
What are the 3 steps a true pathogen should do?
Adhere
Evade
Infect
Give examples of true pathogens
S. Aureus
Neisseria gonorrhoeae
Rhinovirus
Give an example of an infection that is NOT infectious
Urinary tract infection
What percentage of all deaths does infectious disease cause in developed world
More than 25%
Why has the number of TB and HIV cases risen from 2005?
Stop wide use of tb vaccine. Tb linked to HIV as patients with poor immune system more likely to get TB because can’t fend off infection.
TANDEM INFECTIONS.
What are the two common types of pneumonia infection and how many deaths does this disease cause in the uk per year
HAP - hospital acquired
CAP - community associated
U.K. Deaths 30,000 a year
Name infections of concern in developed world
Pneumonia Tuberculosis GI infections Device related Healthcare associated infections Sexually transmittted
Name a microorganism that causes pneumonia
S. pneumonieae
Name a microorganism that causes TB
M. Tuberculosis
Name sime microorganisms that cause gastrointestinal infections
Norovirus
Campylobacter
Name some microorganisms that cause device related infections
S. epidermidis
S. aureus
Name some microorganisms that cause HAI
MRSA
C. Diff
Carbapenemase-producing gram neg rods (klebsiella)
Name some microorganisms that cause sexually transmitted infections
Chylamidia trachomatis
N. gonnhoreae
Treponema pallidum
Name the top 5 causes why infection has spread in developed countries
Ease of travel - get endemic infections of other countries Medical interventions Overuse of antibiotics Contraceptive pill (STI) Modern life - Grindr, drugs, alcohol
Name the top 6 infections of concern in DEVELOPING NATIONS such as subsaharan Africa and Asia
HIV AIDS MALARIA TB DIARRHOEAL DISEASE EBOLA
How many percentage of worlds HIV infections, and AIDS related deaths are in developing nations
70% HIV
80% AIDS
What percentage of global malaria burden is in developing nations
90!!
What does 40% represent in terms of TB
Percentage of all cases of TB in developing world
What are the factors increasing spread of infection in developing nations
Flooding Poverty/overcrowding /malnutrition Poor infrastructure for treatment Climate change and flooding Increased HIV Lack of education
How can infectious diseases be classified by microorganism
Bacteria Parasites (multicellular worms, Helminths, unicellular protozoa) Fungi Viruses Anthropods
Example of gram positive bacilli
C diff (anaerobic ) Bacillus anthracis (aerobic)
Example of gram neg cocci
N. gonorrhoeae
How much of Earth’s biomass is microorganisms and what percentage is pathogenic to humans?
60% and 0.5% of that.
Gram neg aerobic bacilli
N. enterobacteria - ecoli
Pseudomonads - p. Aeruginosa
Parvobacteria - haemophilus influenzae
Vibrios- campylobacter jejuni
Gram neg anaerobic bacilli
Bacteroides sp
What conditions to bacteroides like
Back of throat, low oxygen levels
Which if the following doesn’t have a cell wall?
T. Pallidum, m. Tuberculosis, m. Pneumoniae, c. Trachomatis
Mycoplasma pneumoniae
Why are mycobacterium filamentous
High GC content of DNA
What shape is microorganisms that cause syphilis
Spiral
What are 2 main types of parasites
Protozoa and helminths
Are Protozoa eukaryotic or prokaryotic?
Unicellular eukaryotic
Example of Protozoa
Giardia intestinalis
Identify a GI parasite and a blood/tissue parasite
GI ascaris or giardia
Blood/tissue plasmodium sp.
What are the two forms of Protozoa in infection
Trophozite - metabolically active
Cyst - spread in environment when conditions are poor
Two types of fungi
Moulds and yeasts
How to yeasts reproduce
Budding
How do moulds reproduce
Spores
What are branching filaments of moulds
Hyphae
Example of reovirus and symptoms
rotavirus cause diarrhoea
Name two RNA viruses
Reovirus (rotavirus)
Retrovirus (HIV)
Name two DNA viruses
Herpesvirus (herpes simplex)
Papovavirus (human papillomavirus)
What are Arthropods
Louse
Ticks
Mites
Name two mechanisms on infection by arthropods
Directly - feed on human blood or tissue (pubic lice)
Indirectly - transmission of viruses/parasites to humans (mosquitos)
Asia and South Africa have what percentage of the worlds HIV burden
70%
