Unseen Worlds: Microbes and You

What is Microbiology?

• Microbiology is the study of small living things.

• "Micro" + "Biology": literal meaning; scientific focus on microbes (microorganisms and viruses).

• Major groups:

  • Bacteria

  • Fungi (Yeast and Mold)

  • Viruses

  • Helminths

  • Protists (Protozoa and Algae)

How small is small?

• Size references (from Foundations in Microbiology, Talaro & Talaro, 2001; Edition 4)

• $1\,\text{mm} = 1000\,\mu\text{m}$

• $1\,\mu\text{m} = 1\,\text{micrometer} = 1\,\text{micron}$

• Red blood cell width: $6-8\,\mu\text{m}$

Microbes are Everywhere

• Microbes are found in abundance in air, soil, water, vegetation, etc.

• They are found in/on:

  • Food we eat

  • Water we drink

  • Air we breathe

  • Surfaces we touch

Scope of Microbiology

• Bacteriology: study of bacteria

• Mycology: study of yeasts and molds

• Protozoology: study of protozoa

• Phycology: study of algae

• Parasitology: study of parasites (protozoa and helminths)

• Virology: study of viruses

Microbes and You

• Most microbes do not cause disease; only a minority are pathogenic.

• The majority of microbes are harmless or helpful.

7 Microbe Facts

• They are small – mostly

• They are not simple

• There are no good or bad microbes - their only goal is to survive and reproduce

• Although microbes are everywhere, no one kind of microbe is everywhere. Each microbe has a preferred environment

• The importance of microbes can be underappreciated or oversold

• There are likely hundreds of millions of microbial species on the planet, and there are more and more microbes being discovered

• Microbes are critical to our past, present, and future

Why Microbes Matter: Global Ecosystems

• Most microbes are beneficial to the environment

• Photosynthesis by cyanobacteria generates $50\%$ of Earth’s O₂

• Many are decomposers that recycle nutrients

Why Microbes Matter: Agriculture

• Essential in the gut of the cow for digestion of grasses

• Nitrogen fixation for soil/plant health

Why Microbes Matter: Food Production/Food Safety

• Microbial fermentation processes

• Food and product additives, flavors, and aromas

• Examples: sausages, sauerkraut, beer

Why Microbes Matter: Natural Resources In the Environment

• Bioremediation

• Sewage treatment

Why Microbes Matter: Industry

• Pharmaceutical/Biotechnology Industries

• Pharmaceutical products come from manipulating bacteria – Insulin – Growth hormone

• Vaccine manufacture – Hepatitis B – Cervical cancer

Why Microbes Matter: Human Health

• In the Human Body: the human microbiota at 18 different locations (each of us has a unique community)

• Infectious agents:

  • < 1% of bacteria are pathogenic for humans

  • < 0.2% of fungi are pathogenic for humans

• Microbes as therapy:

  • Probiotics

  • Vaccines

  • Gene therapy

Childhood Mortality & Infectious Disease

• Conditions related to neonatal mortality and infectious diseases are the cause of most under-five deaths around the world

• UNICEF 2023 data (illustrative percentages on the slide):

  • Prematurity — $14\%$

  • Lower respiratory infections (pneumonia) — $0.2\%$

  • Birth asphyxia/trauma — $1\%$

  • Malaria — $2\%$

  • Diarrhoea — $2\%$

  • Congenital anomalies — $3\%$

  • Injuries — $3\%$

  • Sepsis — $5\%$

  • Tuberculosis — $8\%$

  • Measles — $18\%$

  • Meningitis/encephalitis — $9\%$

  • HIV/AIDS — $9\%$

  • Tetanus — $12\%$

  • Other under-five deaths — $14\%$

WHO: Top 10 Threats to Global Health

• These are the 10 biggest threats to global health in 2019 (WHO)

• 1. Air pollution and climate change

• 2. Noncommunicable diseases

• 3. Global influenza pandemic

• 4. Fragile and vulnerable settings

• 5. Antimicrobial resistance

• 6. Ebola and other high-threat pathogens

• 7. Weak primary healthcare

• 8. Vaccine hesitancy

• 9. Dengue fever

10. HIV

Applied Microbiology

• Biotechnology: recombinant DNA technology or genetic engineering

• Medical microbiology: the study of the pathogenic microbes and the role of microbes in illness

• Pharmaceutical microbiology: the study of microbes that are related to the production of antibiotics, enzymes, vitamins, vaccines

• Industrial microbiology: the exploitation of microbes for use in industrial processes

• Food microbiology: the study of microbes causing food spoilage & foodborne illness

• Agricultural microbiology: the study of agriculturally relevant microorganisms

• Plant microbiology and Plant pathology

• Soil microbiology

• Environmental microbiology: the study of the function and diversity of microbes in their natural environments. Includes: Microbial ecology, Bioremediation: use of micro- organisms to clean air, water and soils

Microbes: integral to Human, Animal and Environmental Wellness

• One Health: an integrated, unifying approach that aims to sustainably balance and optimize the health of people, animals and ecosystems

• Globally: World Health Organization (WHO), United Nations (UN), Food and Agriculture Organization (FAO), World Organization for Animal Health (OIE)

• At Home: Center for Disease Control (CDC), USDA

UN Sustainable Development Goals 2015-2030

• 17 goals committed to by world leaders to combat poverty, hunger, disease, illiteracy, environmental degradation, and discrimination against women

• Meeting these goals will require changes in global systems and sustainability

• Many are impacted by microbes including 1, 2, 3, 6, 7, 8, 12, 13, 14, 15, and indirectly 4, 5, 8, 9, 10, 11

Microbiology Today: Current/Future Challenges

• Food Security

• Access to clean water

• Antibiotic Stewardship

• Antibiotic Resistance

• Climate Change

• Biodiversity loss

• Emerging Diseases/Pandemics

• Immunization/ Vaccine hesitation

• Bioterrorism

Terminology

• Microbiology

• Micron

• Bacteriology

• Mycology

• Protozoology

• Phycology

• Parasitology

• Helminth

• Virology

• Pathogen

• One Health

• Bioremediation

• Microbiota

• Microbiome

• Biotechnology

• Medical microbiology

• Pharmaceutical microbiology

• Industrial microbiology

• Food microbiology

• Agricultural microbiology

• Environmental microbiology

• Sustainability

Terminology Definitions

• Microbiology: The study of small living things, focusing on microbes (microorganisms and viruses).

• Micron ($\mu\text{m}$): A unit of length equal to one-millionth of a meter, used to measure the size of microscopic organisms.

• Bacteriology: The study of bacteria.

• Mycology: The study of yeasts and molds (fungi).

• Protozoology: The study of protozoa.

• Phycology: The study of algae.

• Parasitology: The study of parasites, including protozoa and helminths.

• Helminth: A parasitic worm; part of the major groups of microbes studied in microbiology.

• Virology: The study of viruses.

• Pathogen: A microbe that causes disease.

• One Health: An integrated, unifying approach balancing and optimizing the health of people, animals, and ecosystems.

• Bioremediation: The use of microorganisms to clean air, water, and soils.

• Microbiota: The community of microorganisms in a specific environment, such as the human body.

• Microbiome: The collection of all microbes, their genes, and environmental conditions in a particular habitat.

• Biotechnology: The application of biological processes for industrial and other purposes, often involving recombinant DNA technology or genetic engineering.

• Medical microbiology: The study of pathogenic microbes and their role in illness.

• Pharmaceutical microbiology: The study of microbes related to the production of antibiotics, enzymes, vitamins, and vaccines.

• Industrial microbiology: The exploitation of microbes for use in industrial processes.

• Food microbiology: The study of microbes causing food spoilage and foodborne illness.

• Agricultural microbiology: The study of agriculturally relevant microorganisms, including plant microbiology, plant pathology, and soil microbiology.

• Environmental microbiology: The study of the function and diversity of microbes in their natural environments, including microbial ecology and bioremediation.

• Sustainability: Meeting the needs of the present without compromising the ability of future generations to meet their own needs, often impacted by microbial processes.

The 7 Microbe Facts

1. They are small – mostly: The vast majority of microbes are microscopic.

2. They are not simple: Despite their size, microbes have complex biological processes and genetic makeup.

3. There are no good or bad microbes: Microbes exist on a spectrum; their impact is context-dependent. Some are beneficial, some are harmful, and many are neutral.

4. Their only goal is to survive and reproduce: Like all living organisms, microbes are driven by the fundamental biological imperatives of survival and procreation.

5. Although microbes are everywhere, no one kind of microbe is everywhere: Different microbes thrive in different specific environments due to their unique physiological requirements.

6. Each microbe has a preferred environment: Microbes are highly adapted to particular niches (e.g., temperature, pH, nutrient availability).

7. The importance of microbes can be underappreciated or oversold: Their true impact on global ecosystems and human well-being is often misunderstood and can be either underestimated or exaggerated.

Five Ways Microbes Matter in the Environment and to Society

1. Global Ecosystems: Most microbes are beneficial to the environment. Photosynthesis by cyanobacteria generates $50\%$ of Earth’s O₂, and many microbes act as decomposers, recycling essential nutrients.

2. Agriculture: Microbes are essential for processes like nitrogen fixation, which is crucial for soil and plant health. They are also vital in the digestive systems of livestock, such as the gut of cows for grass digestion.

3. Food Production/Food Safety: Microbial fermentation processes are fundamental to producing various foods and beverages (e.g., sausages, sauerkraut, beer). They also contribute to food and product additives, flavors, and aromas.

4. Natural Resources in the Environment: Microbes are utilized in bioremediation to clean up pollutants in air, water, and soil. They are also critical components in sewage treatment processes.

5. Industry (Pharmaceutical/Biotechnology): Microbes are manipulated to produce pharmaceutical products like insulin and growth hormone, and they are integral to vaccine manufacturing (e.g., Hepatitis B, cervical cancer vaccines).

WHO Top 10 Threats to Global Health (2019) Related to Microbes

These threats highlight areas where microbiology plays a crucial role in prevention, diagnosis, and treatment:

1. Global influenza pandemic: Caused by viruses.

2. Antimicrobial resistance: The ability of microbes (bacteria, fungi, viruses, parasites) to resist the effects of drugs, making infections harder to treat.

3. Ebola and other high-threat pathogens: Caused by viruses and other microbial agents.

4. Vaccine hesitancy: Directly impacts the control and eradication of microbe-caused infectious diseases.

5. Dengue fever: A viral disease transmitted by mosquitoes.

6. HIV: A viral infection.

Sustainability and Global Systems/Problems Relation to Microbiology

Microbes are critically linked to global sustainability and various societal problems. The UN Sustainable Development Goals 2015-2030, which aim to combat poverty, hunger, disease, illiteracy, environmental degradation, and discrimination, are significantly impacted by microbes. For example:

• Goals related to health (Goal 3) directly involve understanding and controlling pathogenic microbes and leveraging beneficial ones for therapy (e.g., vaccines, gene therapy).

• Goals related to food security (Goal 2) rely on microbial processes like nitrogen fixation in agriculture and their role in food production and safety.

• Goals related to clean water and sanitation (Goal 6) are directly addressed by microbial processes in sewage treatment and bioremediation.

• Goals related to climate action (Goal 13) and life on land/water (Goals 14, 15) involve microbial contributions to global ecosystems, such as oxygen generation via photosynthesis and nutrient recycling.

• Goals related to industry and innovation (Goals 7, 8, 9) utilize microbes in biotechnology for renewable energy, industrial processes, and pharmaceutical production.

Microbiology provides solutions and challenges for achieving these global goals, underscoring its relevance to the One Health approach, which recognizes the interconnectedness of human, animal, and environmental health.

9 Challenges Facing Microbiology Today

1. Food Security: Ensuring adequate and safe food production for a growing global population, often involving microbial interventions in agriculture and food safety.

2. Access to clean water: Developing and implementing microbial solutions for water purification and preventing waterborne diseases.

3. Antibiotic Stewardship: Promoting the responsible use of antibiotics to preserve their effectiveness.

4. Antibiotic Resistance: Combatting the global threat of drug-resistant microbes.

5. Climate Change: Understanding and mitigating the impact of climate change on microbial ecosystems and disease patterns.

6. Biodiversity loss: Investigating the role of microbial diversity in ecosystem health and the consequences of its decline.

7. Emerging Diseases/Pandemics: Rapidly identifying, tracking, and controlling new and re-emerging infectious diseases caused by microbes.

8. Immunization/Vaccine hesitation: Addressing public concerns and misconceptions about vaccines to improve global immunization rates.

9. Bioterrorism: Preparing for and responding to potential threats involving the deliberate release of pathogenic microbes.