Microbiology of Waters

1. MICROBIOLOGY OF WATERS
Àlex Mezquida López
Oliver Rodés
Miquel Salgot de Marçay
University of Barcelona
Spain

2. ORGANISMS IN WATER
Water bodies are the habitat for:
 Macroorganisms (fish, macroinvertebrates, mammals,
crocodiles, plants...)
 Microorganisms (bacteria, virus, protozoa,
microalgae…)

3. ORGANISMS IN WATER
• Microorganisms (not typical from water, e.g. from
faecal origin) can survive in water but not develop
there. It is a way for being transported to the host
• The few that survive have an increased “capacity for
infection” or “high pathogenic power in reduced
amounts”
• Virus cannot multiply in water bodies, but free,
associated to bacteria, parasites and suspended
solids can reach the consumer

4. • Types:
Infections by (bacteria, viruses and parasites)
PATHOGENS
Intoxication (only bacterial by-products)
Other (e.g. algal toxins)
IMMUNE SYSTEM
ACTIVATES
Basics of Microbiology: Illnesses

5. HOW THE PATHOGENS REACH THE CONSUMER
(through WATER)
DRINKING
• Adhered to solid particles and sediments (e.g. clay)
• Mobilized by water (kinetic energy)
• Directly suspended in water
BY CONTACT
• Indirectly (e.g. clothes, irrigated food, etc.)
• Contact with the skin or mucosae
BREATHING
• Aerosols

6. Once inside the body, there is an answer
of the immune system (the human body counteracts)
FAGOCITOSIS (BACTERIA, VIRUSES…) by white blood cells
(leucocytes)
White blood cell
Pseudopod Bacteria

7. POLLUTED WATER-RELATED ILLNESSES (biological origin)
Water-related health problems are caused by organisms (illnesses)
or chemicals (usually called toxicity)
Organisms or derived:
• Existing in natural water:
– Bacteria
– Parasites
– Virus
– Some chemicals from biological origin
• The role of water: just transportation (water is innocent)

8. MICROBIOLOGICAL ANALYSIS OF WATER
• Directly (protozoa, worms, bacteria, viruses… )
• By using indicators (for bacteria and viruses)
• Indirectly: techniques detecting parts of the organisms

9. MICROBIOLOGICAL ANALYSIS OF WATER
• Indicators
“Water quality through the presence of pathogenic enteric
microorganisms may affect human health. Coliform bacteria,
Escherichia coli and coliphages are normally used as indicators of
water quality”
Then, it is not necessary to determine all pathogens that can appear
in water (it refers to bacteria and viruses only/mainly)
Other organisms are analysed directly (protozoa…)

10. WATER MICROBIOLOGY
By size, bigger to smaller:
 PARASITES
 BACTERIA
 VIRUS
 PRIONS
Other (not by size): MOULD, YEASTS and ALGAE

11. GROWTH FACTORS OF MICROORGANISMS
How and why microorganisms grow or not out of the body
1. Temperature
• Psicrophyll(e)s (2.5 – 20ºC) (a)
• Mesophyll(e)s (3 – 45ºC)
• Thermophyll(e)s (30 – 65ºC)
2. Oxygen
• Anaerobic (Facultative and compulsory)
• Microaerobic
• Aerobic
3. Free water (water
activity)
4. pH (Acidity)

12. SIZE OF BACTERIA
Bacteria over the tip of a needle
1µm is the result of dividing 1 mm by 1,000
100µm 20µm 1µm

13. BACTERIA
Unicellular organisms from the Protista group. Single cells variable on size
from 0.2 µm to 50 µm; average dimensions between 0.5 and 1 µm

14. 1. Scheme 2. Escherichia coli in several
division phases
BACTERIA MULTIPLICATION BY DIVISION
A
B
C

15. BACTERIA MULTIPLICATION

16. • Successive pictures of an
Arthrobacter colony
growth, from a single
cell, in a 40 hours period
BACTERIAL GROWTH

17. USEFUL BACTERIA : BIFIDOBACTERIUM

18. Propionebacterium, helps to obtain Swiss cheese.
BACTERIAL GROWTH

19. CLOSTRIDIA
Inclusion body
Spore

20. CLOSTRIDIA

21. Clostridium tetani and C. perfringens

22. Enterococci spp
Indicators of faecal contamination by bacteria

23. Its presence indicates lack of hygiene, is a good indicator of faecal pollution
MICROORGANISM Enterococcus genera
Range of growing
temperatures
• Growth between 10 and 45 ºC
• Optimum: 37 - 41 ºC
Where is it found • Gastrointestinal tract and faeces of animals
Associated facilities • Water for leisure activities, swimming pools, theme parks with water
• Water for human consumption, wastewater
Elimination • Adequate control on potable water treatment facilities with
Pre-oxidation, coagulation, flocculation, settling, filtration over sand and with
membranes, disinfection, activated carbon filters, etc. systems
Prevention methods • Periodical analytical controls
• Follow the standard procedures as indicated in rules, regulations and technical
guidelines
• Use adequate and authorized techniques, mechanisms and products
Additional information • The Enterococcus genera has 12 species. It is characterized to be highly
resistant, being tolerant to high salt concentrations (up to 6.5 % of NaCl in the
environment) and to acids.
Enterococci

24. Escherichia coli

25. ILLNESS COLIBACILOSIS (only a few strains)
MICROORGANISM Escherichia coli
Range of growing
temperatures
• Growth between 10 and 45 ºC
• Optimum: 37 - 41 ºC
Where is it found • Gastrointestinal tract and faeces of all hot blooded animals and men
Associated facilities • Water for leisure activities, swimming pools, theme parks with water
• Water for human consumption, wastewater
Elimination • Adequate control on potable water treatment facilities with
Pre-oxidation, coagulation, flocculation, settling, filtration over sand and with
membranes, disinfection, activated carbon filters, etc. systems
Prevention methods • Periodical analytical controls
• Follow the standard procedures as indicated in rules, regulations and
technical guidelines
• Use adequate and authorized techniques, mechanisms and products
Additional information • Is the classical indicator of faecal contamination of water by bacteria
Escherichia coli

26. Legionella pneumophila
Infection by inhalation
Is considered highly
dangerous: In many
countries has its own rules
and regulations for control
and analysis

27. ILLNESS LEGIONELLOSIS
MICROORGANISM Legionella pneumophila
Range of growing
temperatures
• Variable between 20-45 ºC
• Optimum: 35-40 ºC
Where is it found • Natural surface waters
• Biofilms
Intracellular: amoeba and ciliated protozoa
• Water distribution networks, especially sanitary water
Associated facilities • Hot water networks
• Cooling towers
• Bathtubs, spa, hot water swimming pools, jacuzzi
• Cold water networks
• Sprinklers and ornamental fountains
• Humidifying devices
• Air conditioning condensers
• Shower devices
Elimination • Adequate control on potable water treatment facilities with
Pre-oxidation, coagulation, flocculation, settling, filtration over sand and with
membranes, disinfection, activated carbon filters, etc. systems
Legionella pneumophila

28. Prevention methods • Periodical analytical controls
• Follow the standard procedures as indicated in rules, regulations
and technical guidelines
• Use adequate and authorized techniques, mechanisms and
products
• Is difficult to eliminate in cooling towers and water distribution
networks
Additional information • This bacteria has found an adequate habitat in the water networks
manipulated by man where can be amplified and widely distributed.
• More than 40 strains with more than 64 sero groups are described.
• Biofilms in water networks are considered as reservoirs as well as
amoeba (in pipes, water tanks, cooling towers, water wearing devices
like cleaning vehicles using water…)
Legionella pneumophila

29. PROTOZOA: GIARDIA LAMBLIA

30. WATER-RELATED PARASITES
GIARDIA LAMBLIA
Cyst: is the infective
and resistant form
which will be present
in food and water
Trophozoite:
is the form
living, eating
and reproducing
in the host body
Pathogenicity: is mainly due to its effects when being adhered and fixed to the
gut epithelium, acting over the microvilli
Its incubation period is from 1 to 3 weeks. Man is the only host
Symptomatology: Lasts for 2 to 6 weeks. Diarrhoea, belly distension and
abdominal pain, anorexia
To note: resists chlorination of water

31. OOCYSTS: CRYPTOSPORIDIUM

32. In water oocysts can be found,
extremely resistant thanks to their
protecting structures
Pathogenicity: 2-14 days Incubation, with symptoms up to 2 weeks in healthy
persons
For immuno-depressed people can be deathly
Symptomatology:
Watery diarrhoea, also belly spasms, nausea, mild fever, dehydration and loss of
Symptoms appear 4 to 6 days after infection
To note: resists chlorination of water
WATER-RELATED PARASITES
CRYPTOSPORIDIUM PARVUM

33. Round worms: long, cylindrical and not-segmented body. Size from
less than 1 mm to several cm
Can cause haemorrhages, anaemia, paleness, loss of weight,
diarrhoea syndrome, general feeling of discomfort, etc.
ÁSCARIS LUMBRICOIDES ANCYLOSTOMA DUODENALE TRICHURIS TRICHIURA
WATER-RELATED PARASITES:
NEMATODES

34. Pathogenicity: Especially dangerous for pregnant women, the infection can be
transmitted to the foetus, and also for immuno-depressed individuals. Man is and
intermediary host being the definitive one the cat
Symptomatology:
For healthy people the symptomatology is similar to the flue
For the foetus the consequences are malformations and heart, liver and brain
affectation
In immuno-depressed individuals can cause deathly encephalitis
1. Sporulated
oocysts: Is the form
of resistance in the
environment
2. Bradizoite:
In the meat of infested mammalian:
lambs, pigs and cows
3. Tachyzoite:
In the organs of human body
WATER-RELATED PARASITES
TOXOPLASMA GONDII

35. TOXOPLASMA GONDII

36. WORMS: NEMATODA

37. VIRUS

38. AIDS virusBacteriophage (model)
VIRUS

39. VIRAL FORMS

40. INFECTION: VIRUS “LYSIS CICLE”

41. • Fungi and yeasts
• Algae and its “by-
products”
OTHER MICROORGANISMS IN WATER