Environmental Factors Flashcards by Miriam NugaSama

6 Examples of environmental risk factors

Air
Water
Soil pollution
Chemical exposures
Climate change
Ultraviolet radiation

How well did you know this?

Not at all

Perfectly

3 Top causes of environmental related deaths due to microorganisms

Diarrhoeal diseases
Respiratory infections
Malaria

How well did you know this?

Not at all

Perfectly

4 Abiotic environmental factors

wind
water
inhalation of spores
entry into skin

How well did you know this?

Not at all

Perfectly

What are the 3 common ways pathogens are spread from one person to another?

Direct contact
Respiratory aerosols
Faecal-oral transmission

How well did you know this?

Not at all

Perfectly

What are the 3 main categories of how we become infected by the microorganisms in the environment?

Natural phenomena or disasters bring individuals in contact with opportunistic pathogens

Human activity brings people into contact with opportunistic pathogens

Human activity contaminates the environments with the pathogens

How well did you know this?

Not at all

Perfectly

Where do potential pathogens originate from natural disasters?

From dust storms which damage the respiratory airway

From earthquakes which destroy public health systems

From storms which lead to severe flooding

How well did you know this?

Not at all

Perfectly

Describe Vibrio vulnificus (4 things)

Aquatic organism
halophile
gram -ve
comma shaped

How well did you know this?

Not at all

Perfectly

What 2 types of infections does Vibrio vulnificus cause and where do they occur?

Wound infections
Fulminant sepsis
occur in areas where water temperature remains high all year

How well did you know this?

Not at all

Perfectly

What type of wound infections does Vibrio vulnificus cause? (4)

cellulitis - infection in deeper layer of skin
oedema - swelling due to build up of fluid
erythema
necrosis

How well did you know this?

Not at all

Perfectly

What % of individuals get fulminant sepsis from Vibrio vulnificus

How well did you know this?

Not at all

Perfectly

Vibrio vulnificus is associated with the..

Consumption of raw shell fish

How well did you know this?

Not at all

Perfectly

Describe Legionella pneumophilia

ubiquitous aquatic saprophyte
found in lakes, rivers and streams
thin
pleomorphic
gram-ve
bacillus
obligate aerobe

How well did you know this?

Not at all

Perfectly

What does pleomorphic mean?

changes, morphology, reproductive and other metabolic behaviours in response to environmental changes

How well did you know this?

Not at all

Perfectly

What is an obligate aerobe?

Fussy about nutrition
hard to grow
will only grow in the presence of oxygen

How well did you know this?

Not at all

Perfectly

What is a primary pathogen + examples

A pathogen whose role is to cause disease
example S. aureus

How well did you know this?

Not at all

Perfectly

What is an opportunistic pathogen?

A pathogen that is not really mean to cause disease but will do in the right environment
example V. vulnificus

How well did you know this?

Not at all

Perfectly

What is a viable pathogen?

A pathogen that is not dead but may not necessarily be able to cause disease
metabolically inactive

How well did you know this?

Not at all

Perfectly

What are spores?

Tough structures designed to survive tough/harsh environments

How well did you know this?

Not at all

Perfectly

How does human activity contaminate the environment with pathogens? + examples (2)

Healthcare environments are reservoirs of pathogens
example MRSA

Poverty, deprivation and overcrowding

How well did you know this?

Not at all

Perfectly

example of how poverty, deprivation and overcrowding lead to disease?

inadequate sanitation leads to faecal contamination of drinking water and cholera outbreaks

How well did you know this?

Not at all

Perfectly

What is Hepatitis E? (5)

viral infection
asymptomatic
mild-severe fulminant hepatitis
typically self limiting, no treatments required
typically waterborne but can be foodborne

How well did you know this?

Not at all

Perfectly

How does Hepatitis E spread?

Faecal-oral transmission

How well did you know this?

Not at all

Perfectly

What are the symptoms of Hepatitis E? (4)

Nausea
Loss of appetite
Jaundice
Dark urine

How well did you know this?

Not at all

Perfectly

What is infection of Hepatitis E linked with?

Consumptions of pork products

What is the strategy to reduce diarrhoeal disease?

increase access to safe water provide adequate sanitation promote hand washing

What is the strategy to reduce acute respiratory infections?

use clean technologies and fuels for domestic cooking, heating and lighting

Viable microorganisms are normally found..

in the atmosphere up to 3km above land

4 reasons why the atmosphere is a harsh environment for microorganisms

UV radiation of sunlight Low/high humidity Extreme temperature variation Pollution

Why can microorganisms encountered indoors be beneficial to our health? (2)

organisms are believed to train the immune system too clean environments are linked to increased incidence of allergies and autoimmune diseases

Why can microorganisms encountered indoors be detrimental to our health?

potential pathogens are shed from occupants (both human and animal)

Is the diversity and concentration of microorganisms greater indoors or outdoors?

Indoors

4 examples of fungi that are abundant indoors + fact

Aspergillus Penicillium Alternaria Fusarium - increases with age of dwelling and presence of a cellar

3 examples of bacteria that typically shed from skin

Staphylococcus Streptococcus

Organism typically found in faeces (home)

Bacteroides

4 Organisms associated with domestic animals

Prevotella Porphyromonas Moraxella Bacteroides

How soon can microbiota changes be observed in a household when moving in/out?

Within days

In what environments are microorganisms in the air important? (4)

Hospitals Facilities that manufacture medicinal drugs Manufacturers of implanted medical devices Factories producing food stuffs

In what environments are microorganisms in the air important? (4)

Hospitals Facilities that manufacture medicinal drugs Manufacturers of implanted medical devices Factories producing food stuffs

Microorganism - Myobacterium tuberculosis

Disease - Tuberculosis

Microorganism - Bordatella pertussis

Disease - Whooping cough

Microorganism - Neisseria meningitis

Disease - Meningitis

Microorganism - Corynebacterium diphtheriae

Diphtheria

Microorganism - Streptococcus pyogenes

Disease - Pharyngitis (sore throat)

Microorganism - Legionella pneumophilia

Legionnaires' disease

Microorganism - Aspergillus fumigatus

Aspergillosis

2 impacts of air pollution - respiratory disease

damages the airways or causes chronic respiratory disease damage of chronically diseased airways predisposes individuals to respiratory infections

Example of a primary respiratory pathogen transmitted by air

Myobacterium tuberculosis

What is Myobacterium tuberculosis linked to? (3)

pollution which causes damaged lungs malnutrition which increases an individual's susceptibility to disease overcrowding which facilitates transmission of aerosols

Respiratory aerosols are...

air borne droplets which are usually generated by talking, coughing, spitting and sneezing

Example of an environmental, opportunistic pathogen transmitted by air

Aspergillus fumigatus

Describe Aspergillus fumigatus

approx 250 species but less than 20 cause human disease ubiquitous in the environment

Where does Aspergillus fumigatus grow? (7)

soil on plants in decomposing organic matter dust damp buildings air conditioning systems

Where are Aspergillus fumigatus spores found? (4)

indoors outdoors in water on food

How does Aspergillus fumigatus affect immunocompromised patients?

they are at greater risk of serious invasive life-threatening infections such as invasive aspergillosis with a mortality rate of 50-100%

How common is invasive aspergillosis?

it is rare in healthy people

What are the risk factors for invasive aspergillois? (3)

1. a lung condition - eg asthma, CF or COPD 2. weakened immune system - eg following organ transplant surgery or having chemotherapy 3. had TB in the past

Can aspergillosis be contracted from someone else or from animals?

No, it is a non-communicable infection

What are the symptoms of aspergillosis? (6)

1. shortness of breath 2. a cough - may cough up blood or lumps of mucus 3. wheezing (whistling sound when breathing) 4. a high temperature of 38C or above 5. weight loss 6. if pre-existing lung condition, existing symptoms may get worse