Can plants make us sick?

We’re not talking about something not agreeing with you. We’re asking can plants pass on disease to humans?

Humans have a number of viruses in common with plants and animals. Three such families exist: the Bunyaviruses carried by insects (like mosquitoes, ticks and sandfly) causing the diseases Crimean-Congo Hemorrhagic Fever and Rift Valley Fever and rodents causing Hantavirus infections; the Rhabdovirus better known as rabies causing encephalitis; the Reoviruses which causes gastrointestinal and respiratory disease primarily in infants and young children.

Many of us have experienced dermatitis from poison ivy and other plants. People often misidentify plants and become sickened or even poisoned after ingesting. A fairly common disease throughout the world is Sporotrichosis caused by the fungus Sporothrix. This fungus exists in soils, plant debris, sphagnum moss, hay, and on rose thorns. It usually enters the body through small cuts or punctures from rose thorns ( sometime called the rose-gardener’s disease). It can manifest as small bumps or blisters at entry site, more seriously if breathed in it can cause a type of pneumonia, and if entry wound is near a lymph node it can become disseminated throughout the entire body.

Another common and opportunistic pathogen is Pseudomonas aeruginosa. It’s what causes soft rot in plants, fruits, and vegetables. It is especially dangerous for people with immunity deficiencies causing pneumonia, urinary tract infections, and oral infections. And, similar to the staph that causes MRSA it is antibiotic resistant. Much of what has been mentioned results in disease caused by the myotoxins produced by the bacterium.

More recently in France people have been showing symptoms of fever, aches, and pruritus (a systemic itching usually caused by a disease) after eating peppers with mild mottle virus (PMMoV). Viable virus has been found in salsas, powdered spices, and in the samples of hundreds of people. Viable tobacco mosaic virus has been found in the mucus and thoracic fluids of smokers.

In India tospoviruses causing tomato spotted wilt and groundnut bud necrosis are passed on by insects, thrips, and humans. Live virus is found in ripe tomatoes only to be eaten and passed on through ground and water. Begovirus which causes the tomato yellow leaf curl virus affects tomato production worldwide and, in turn, affects the insects that carry it by shortening their lifespan and their ability to reproduce.

So as you can see, plant diseases have many paths to make humans sick - but none of the pathogens has, of yet, crossed the line of entering the human cell. Plant diseases for now have no direct route as a human pathogen.