Fusarium

*Fusarium* is a group of fungal species (*Fusarium* spp.) that can infect both plants and human beings. Two species of *fusarium* known as *Fusarium* graminearum (*F.* graminearum) and *F.* oxysporum were listed in the top ten for a list of molecular plant pathogens based on both scientific and economic importance. Their effects are almost worldwide as *Fusarium* infections of plants occur in almost all climates. They can infect a wide range of plants, as the American Phytological Society reports that 83/108 plant species have their production affected by *Fusarium*.

## The genus *Fusarium* 
*Fusarium* spp. used to have two different names based on what reproductive stage they were in. However, this naming system was removed, so now most species only have their *Fusarium* name. *Fusarium* spp. can be identified in their spore form under the microscope by how they group up to form banana-shaped clusters. This can be due to *Fusarium* killing the plant through something like stem rot causing the plant to collapse. Another problem is the contamination of the crop with mycotoxin. 

*Fusarium* infections in plants have no cure, making them devastating for crops. In fact, using fungicides could actually cause *Fusarium* to produce more mycotoxin. Mycotoxins are problematic because they can get into our food and damage our health. 

## Mycotoxin 
The level of mycotoxin allowed in our food is kept below one part per million (ppm) in United States of America, or below 0.75 ppm in the European Union. However, there is still a health concern of long-term exposure to small amounts of the mycotoxin.

The mycotoxin is essential for spread of *Fusarium* because inhibiting mycotoxin production makes *Fusarium* unable to spread. However, mycotoxin is not essential for the growth of *Fusarium*. Mycotoxins can be grouped based on their structure. The type of mycotoxin produced is dependent on the species, but a single species can produce several types of mycotoxin. Some well-known groups include trichothecenes, fumonisin, giberellic acid, and zearalenone.

## *Fusarium* disease in humans 
*Fusarium* spp. can live on human skin, mucosa and gut. In a healthy person, the *Fusarium* that lives on us is harmless. However, there is a rare chance of infection, but this usually happens to people with weakened immune systems. Infections can be local, only affecting a certain body part. For example, *Fusarium* can grow in contact lens solution, and if it enters the eye, it can cause inflammation of the cornea or even ulceration. However, if the *fusarium* fungus gets into the bloodstream, it becomes a systemic infection known as system fusariosis. Only a few strains of *Fusarium* can grow at body temperature (37°C). Systemic fusariosis has a 50-80% mortality rate. This is because there is no treatment or cure currently available. If infection spreads to the lungs, it can cause pneumonia.

## Diagnosis of *Fusarium* infection 
An infection of the skin can be diagnosed by a visual inspection. To test for an eye infection, a sample must be taken and cultured. Similarly, for a systemic infection, a culture is taken from the blood. 

## Treatment of systemic fusariosis 
Some antifungals have been successfully used to treat systemic fusariosis such as amphotericin B and voriconazole. However, the lack of large-scale clinical studies means there is currently no approved treatment for *Fusarium* infections. Since immunocompromised patients are most at risk, they can be put into isolation to reduce the chance of being exposed to *Fusarium*. However, since *Fusarium* spp. live naturally in our gut, these fungi can start an infection from within. Therefore, there is no way to reliably prevent or cure *Fusarium* infections.

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