What is the Problem?

An Overview of Soil-Borne Illnesses

25% of the global burden of disease is attributable to environmental factors, including soil-borne illnesses. (World Health Organization)

Soil-borne illnesses — infections caused by microorganisms that lurk in the soil. These tiny organisms can wreak havoc on humans, animals, and plants that come into contact with contaminated soil.

Soil-borne illnesses are a big deal. They cause serious health problems such as vomiting, fever, and even death.

Soil-transmitted helminth (STH) infections are among the most common infections worldwide with an estimated 1.5 billion infected people or 24% of the world’s population.

This is a real concern in areas with poor sanitation, where people may be exposed to contaminated soil while farming or participating in other outdoor activities.

These infections affect the poorest and most deprived communities with poor access to clean water, sanitation and hygiene in tropical and subtropical areas, with the highest prevalence reported from sub-Saharan Africa, China, South America and Asia.

What Causes Soil-Borne Illnesses?

Soil-borne illnesses are caused by microorganisms that live in the soil and infect the roots or other parts of the plant. These microorganisms include bacteria, fungi, viruses, and parasites.

Soil Microbes and It’s affect on animals and humans

Microorganisms in soil are introduced through natural processes and human activities.

• Natural Processes → Decay of organic matter and the activities of living organisms can introduce microbes to soil.
• Human Activities → Agricultural practices, use of contaminated water or soil amendments can also introduce pathogens to soil.

Once introduced, microorganisms can persist in soil and form complex interactions with other organisms, affecting plant health and the soil ecosystem.

When a plant grows in soil that is contaminated with these microorganisms, the microorganisms can enter the plant through the root system. The microorganisms may then multiply and spread within the plant, causing various types of diseases that can affect the growth and health of the plant.

Schematic of microbiome surrounding a plant throughout its life history

In the case of bacterial and fungal infections, the microorganisms may secrete enzymes or toxins that damage the plant cells and tissues, leading to symptoms such as wilting, yellowing, or necrosis (tissue death).

These infections weaken the plant’s immune system, making it more susceptible to other types of infections or environmental stresses.

How Does This Impact us?

Soil-borne illnesses have a immense impacts on people and surrounding communities. Rather its through direct or indirect consumption, its a problem that trickles down to everybody, because… we all need food to survive.

Directly → Consumption of Contaminated Plants

When people consume or come in specific contact with contaminated plants or plant products, such as fruits, vegetables, grains, or nuts. Those contaminated plants carry harmful microorganisms that can cause illness when ingested.

Some of the most common and well-known examples of soil-borne pathogens are:

• Salmonella → A group of bacteria commonly found in the intestines of animals. Causes food poisoning and can survive in soil for months to years.
• Escherichia coli → A strain of E. coli that can cause severe gastrointestinal illness, including bloody diarrhea, abdominal cramps, and vomiting. It’s commonly associated with contaminated ground beef, but can be found in soil and water.
• Clostridium tetani → A spore-forming bacterium that causes tetanus, a serious disease that affects the nervous system. C. tetani spores can persist in soil for many years and can enter the body through puncture wounds, such as those caused by rusty nails or animal bites.
• Bacillus anthracis → A spore-forming bacterium that causes anthrax. Anthracis spores can survive in soil for decades and can enter the body through cuts or abrasions in the skin or by inhalation of spores.
• Histoplasma capsulatum → A fungus that causes histoplasmosis, a respiratory disease. H. capsulatum spores are found in soil contaminated with bird or bat droppings and can be inhaled, causing lung infection.
• Toxoplasma gondii → A parasite that can cause toxoplasmosis. T. gondii is commonly found in soil contaminated with cat feces and can be transmitted through ingestion of contaminated food or water.

Indirectly → Soil-borne Illnesses Affect Agricultural Production and Food Security

Soil-borne illnesses in plants affect agricultural production and food security.

When plants are infected or damaged by soil-borne microorganisms, their yields are reduced and their quality is compromised. This leads to economic losses for farmers and reduced availability or affordability of food for local communities/consumers.

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