Respiratory (Air-borne) Diseases

Question 1

What are the 4 gases that make up air?

Answer 1

1. nitrogen - 78%
2. oxygen - 21%
3. argon - 0.9%
4. air pollutants - 0.1%

Question 2

Most respiratory diseases are due to inhaling harmful air pollutants from the air. What are the 3 classes of air pollutants?

Answer 2

1. harmful gases
2. particles
3. airborne pathogens

Question 3

What law was passed in the USA to control air pollution? What does it focus on controlling?

Answer 3

1970 Clean Air Act - clean air should be maintained in houses, workplaces, hospitals, surgery rooms, industries, and slaughterhouses

air-borne contaminants in the atmosphere, or else microbes from the air will drop into wounds, surgical sites, food, and meat, or be inhaled and cause disease

Question 4

Why is exposure to air pollutants so significant?

Answer 4

it is continuous and involuntary - cannot be avoided

Question 5

What 6 types particulate matter pollute the air?

Answer 5

1. AEROSOLS - any tiny solid or liquid particles
2. DUSTS - solid particles from grinding or crushing
3. FUMES - solid particles occurring when vapors condense
4. MIST/FOG - liquid particles
5. SMOKE, SOOT, ASH - solid particles (carbon) from combustion
6. SMOG - any air pollutant

Question 6

What are the 6 major air pollutants that are known to cause smog, acid rain, and health hazards?

Answer 6

1. O3
2. CO
3. SO2
4. NO2
5. particulate matter
6. lead

Question 7

What are the 4 broad types of air pollutants that cause air-borne disease?

Answer 7

1. biological - COVID-19, SARS, flu, TB, Chlamydia, Q fever, anthrax, fungi
2. allergens - cats, mites
3. physical - particulate matter, volcanic ash, radioactivity, cement dust, smoke from fires
4. chemical - gases, ammonia, CO, CO2, SO2, NO2, methane, chlorofluorocarbons

Question 8

What type of air pollutants make up most of the total mass emitted into the atmosphere?

Answer 8

chemical gases = 90%

Question 9

What are the 3 types of particulate matter based on size?

Answer 9

1. inhalable coarse particles with a diameter of 2.5-10 µm (PM10)
2. fine particles with a diameter of 0.1-2.5 µm (PM2.5)
3. ultrafine particles with a diameter of 0.1 µm or less (soot)

they are all able to be suspended in the air and inhaled

Question 10

What is the typical size and make-up of particulate matter? What is their porosity like?

Answer 10

0.01-100 µm —> solid or aqueous

such that they can absorb/adsorb other gases, liquids, and solids

Question 11

What kind of particulate matter is the most dangerous? What 4 things do they most commonly cause?

Answer 11

those below 2.5 µm, since they can penetrate all sites of the respiratory tract

1. heart attacks
2. respiratory disease
3. premature death
4. cancer (group 1 carcinogens)

Question 12

Air-borne hazards that cause allergies, cancer, respiratory/lung disease, and cardiovascular disease:

Answer 12

Question 13

Air-borne pathogens:

Answer 13

Question 14

What is characteristic of air-borne pathogen transmission?

Answer 14

can jump from animals to humans and jump back from humans to animals

Question 15

What pathogens are more significant in the air? Why? How are they transmitted?

Answer 15

viruses, bacteria, fungi —> parasites and protozoa are too large to stay suspended in the air and be inhaled

launching pathogens and spores of pathogens from the ground into atmospheric air, like a parachute (sneezing/breathing)

Question 16

What are the 3 steps required for airborne transmission?

Answer 16

1. launched into air from a donor, like humans, animals, vegetation, water, soil, and industries
2. transported by wind, precipitation, dust, machinery (airplanes), migratory birds, flying insects, and people
3. deposited or landed in a new location on a new recipient, like humans, animals, vegetation, soil, and water

Question 17

How can humans stop the transmission of air-borne pathogens?

Answer 17

cover while sneezing or coughing

Question 18

Viruses, bacteria, and fungal spores able to be launched in the air:

Answer 18

Question 19

What bacteria is known to be launched in liquid particles into the air from water stores?

Answer 19

Legionella is launched in mist (tiny water droplets)

Question 20

What causes Q fever? How is it transmitted? How far can it be transmitted?

Answer 20

Coxiella burnetii

dispersed from animals’ breath from livestock holdings in the wind

20 km

Question 21

Anthrax is mostly transmitted through contact. Where can it be commonly transmitted in the air?

Answer 21

launched from contaminated livestock hides and skin in the leather industry after processing (5%)

Question 22

What are the 3 transmission routes of respiratory zoonotic diseases?

Answer 22

1. person-to-person from direct touches of exhanging of body fluids = contagious disease
2. droplet spread that travels a few feet (close) from coughing, speaking, and sneezing
3. air-borne transmission that travels long distances

Question 23

How is measles transmitted?

Answer 23

air-borne —> can travel long distances
- can catch it by entering a room after someone with measles has departed

Question 24

How does air-borne transmission compare to soil-borne and water-borne transmission?

Answer 24

there are significantly less atmospheric microorganisms, but once they are suspended in the air, they can travel long distances with the help of wind, dust, particulate matter, and precipitation to land on a new recipient

Question 25

Why are air-borne pathogens more likely to become pandemic?

Answer 25

we cannot stop breathing in and out air ---> involunutary ---> easy spread

Question 26

What 3 things do the symptoms of respiratory disease depend on?

Answer 26

1. type of pathogen 2. location of respiratory tract affected 3. severity of damage on the affected respiratory tract

Question 27

What are the 3 major air-borne zoonoses that caused pandemics in history?

Answer 27

1. Yersinia pestis from rodents - Black Plague 2. Influenza virus - 5 flu pandemics 3. Coronavirus - 3 pandemics

Question 28

What are the 4 major emerging zoonotic pathogens of respiratory disease?

Answer 28

1. SARS 2. MERS 3. pandemic influenza 4. Legionella

Question 29

What is the aim to monitoring and surveilling air quality? What 3 hazards are measured when doing this?

Answer 29

prevent and control air-borne diseases if the concentration of hazards in the air is above the maximum acceptable level 1. pathogens - ~50 CFU/m^3 2. hazardous gases 3. particulate matter - coarse (PM10), fine (PM2.5) = 12 µg/m^3

Question 30

Air quality standards for microbial maximum limit:

Answer 30

Question 31

The USA has standards for what 5 classes of air pollutant hazardous gases? What is the maximum limit for particulate matter?

Answer 31

1. sulfur dioxide (SO2) 2. carbon monoxide (CO) 3. ozone (O3) 4. nitrogen dioxide (NO2) 5. lead (Pb) COARSE (PM10) = 150 µm/m^3 FINE (PM2.5) = 12-15 µm/m^3 ---> 35 µm/m^3

Question 32

What are the 9 ways air-borne diseases can be controlled?

Answer 32

1. treating infected/ill people and animals to minimize launching pathogens into the air 2. vaccination to minimize pathogen reproduction and amplification (COVID-19, Influenza) 3. cleaning, sanitizing, and disinfecting environment to reduce germ buildup 4. hand washing thoroughly for at least 20 seconds 5. PPE: masks, cover up coughs and sneezes to reduce launching 6. social distancing: avoid close contact with infected animals and people without PPE 7. using a respirator with HEPA filter 8. quarantine 9. reduce hazardous gas production and release into atmosphere by industries