Air Microbiology. Aerobiology is defined as the study of life present in the air. Aeromicrobiology relates to the study of environmentally relevant microorganisms. ... In dry whether the microbial load of air is high while in wet weather the rain washes the microorganisms from the air.

1. AIR MICROBIOLOGY
Mr. RAJENDRA SINGH Jr.
Biotechnology Network

2. Contents –
1. Introduction
2. Disease caused by air borne microbes
- Bacterial diseases
- Air born fungal diseases
- Air born viral diseases
3. Sources of microorganism in air
4. Microbes in atmosphere
5. Outdoor aero microbiology
6. Indoor aero microbiology
7. Factors affecting microbial survival in air
8. Significance of microorganism in air
9. References

3. AERO-MICROBIOLOGY
• Aerobiology is defined as the study of life present in the
air.
• Aeromicrobiology relates to the study of
environmentally relevant microorganisms.

4. 2. Disease caused by air borne
microbes
Bacterial diseases –
• Brucellosis:
Brucella suis it is mainly an
occupational disease among veterinarian, butcher
and slaughter house workers.

5. • Pulmonary Anthrax:
Anthrax is caused by a spore-
forming bacterium.
It mainly affects animals.
Humans can become infected through contact
with an infected animal or by inhaling spores.

6. Air Borne Fungal Diseases
• Blastomycosis:
Blastomycosis is an infection caused by the
fungus Blastomyces.
The fungus lives in the environment,
particularly in moist soil and in decomposing
organic matter such as wood and leaves.

7. • Aspergillosis:
Aspergillosis is an infection caused by Aspergillus, a common
mold (a type of fungus) that lives indoors and outdoors.
Infection occurs through inhalation of spores. Most people
breathe in Aspergillus spores every day without getting sick.

8. Air Borne Viral Diseases
• Common Cold:
Most people get colds in the winter
and spring, but it is possible to get a cold any time of
the year.
Symptoms usually include sore
throat, runny nose, coughing, sneezing, watery eyes,
headaches and body aches. Most people recover
within about 7-10 days.

9. • Influenza:
Symptoms of influenza are nasal
discharge, head ache, muscle pains, sore throat
and general weakness. Causative agents are
orthomyxovirus.

10. 3. Source of Microorganism in Air
Sources of microbes
in the air
Droplets
Evaporated water
from rivers, ponds,
streams and lakes
Aerosols
Vents
Machine fans
Air conditioners
Dust
Human activities
Ploughing, digging
Irrigation
Fertilizers
Human and Animal
Breathe, talk, Sneeze,
laugh and cough

11. 4. Microbes in Atmosphere
o The atmospheric layers and the airflow pattern are the important forces in
determining the distribution and dynamics of viable particles in air.
o The aero microbiological pathway (AMP) involves the path and pattern of
movement of microbial particles in atmosphere.
o The layer of most interest and significance in aero microbiological is the
boundary layer, which extends up to 0.1km form the earth’s surface.

12. 5. Outdoor Aero Microbiology
 Airborne crop pathogen:
Bioaerosol are of direct relevance to agriculture. Air borne microbial
pathogens are responsible for a large range of important disease of crop plants.
 Waste disposal:
A range of pathogenic microbes, viruses-bacteria, protozoa and
helminthes associates with waste effluents bring about health hazard during their
treatment and disposal handling.

13. 6. Indoor Aero Microbiology
 Private homes and office building:
Extent of bioaerosols development determines the health of any
building. These include several factors that influence the formation of bioaerosols.
 Hospital and Laboratories:
These two indoor environments have such potential for the
aerosolisation of pathogenic microbes. Microbiological laboratories are also a breeding
center for pathogenic microbes.
 Space flight:
Microbes have been detected even from harsh environments. They are
associated with every aspect of life even space craft.

14. 7. Factors affecting microbial survival in air
o Atmospheric humidity:
The relative as well as the absolute humidity content of the air play
a major role in the survival of the air borne microorganism.
o Temperature:
Temperature is the major factor in the inactivation of microbes. High
temperature promotes inactivation, mainly associated with desiccation and protein
denaturation and lower temperature promotes longer survival times.

15. 8. Control of microorganism in air
Ultraviolet Radiation
• This method has great potential value for reducing the
microbial flora of air.
• It is done by following ways :
1. Direct irradiation.
e.g. aseptic filling rooms for pharmaceutical preparations
2. Indirect Irradiation.
e.g. occupied rooms, offices, wards e.t.c.

16. Chemical Agents
• Chemical substances vaporized into air of room are effective in reducing the
microbial flora.
• Chemicals are dispersed as aerosol and show its anti microbial action.
• Characteristics of chemical agent as
germicide:
• It should be highly bactericidal.
LAMINAR AIR FLOW SYSTEMS
• Air passes through HIGHER EFFICACY
PARTICULATE AIR (HEPA) filters.
• Operation.
• Application.
• Natural or mechanical ventilation of rooms.

17. 9. Significance of Microorganisms in Air
 Food manufacture:
 Spoilage of foods and fermentation products:

18. References –
1. Microbiology- Prescott, Harley & Klein’s. 7th
Edition. Published by Mc Graw-Hill.
2. Environmental microbiology, 2008- Pradipta k.
mohapatra, I.K. international publications pvt. Ltd.
3. Environmental microbiology, 2005- P D sharma.
4. WWW. Google.co.in/picture

19. THANKYOU