Coccidioides Immitis Research Paper

Fungal pneumonia has many variations throughout the environment, including Coccidioides. Within Coccidioides, there are two species that are very similar. Coccidioides immitis and Coccidioides posadasii are two parasitic pathogens that affect the lung and can cause flu-like or pneumonia-like symptoms in mammalian bodies.
Coccidioides is a pathogen that is part of the fungal kingdom (Taxonomy Browser). The separation of the species immitis and posadasii has been a relatively new discovery. The separation has allowed the study of these species in different locations in the United States and Central and South America, as well as the migration of these species throughout the North and South American continents (Lewis et al, 2). The entire taxonomic

classification from Kingdom to Genus is: Fungus, Sac Fungus, Eurotiomycetes, Onygenales, Onygenaceae, Dimorphic Ascomycetes (Taxonomy Browser). As stated before, the Coccidioides pathogen is divided in to two separate species; the diseases and problems caused are very similar with these pathogens, but the structures and reservoirs are where we see differences (Kellner et al, 111). Coccidioides immitis contains a parasitic cell wall and are dimorphic (Kellner et al, 111). It also contains spores that are to transform into small spheres, or spherules, and granulomas, or macrophages (Kellner et al, 111). Coccidioides posadasii is also a dimorphic structure, but has many differences in its structure (Kellner et al, 111). The posadasii species has Woronin Bodies, or proteins involved in sealing pores in the cell wall in response to cell damage (Coccidioides Posadasii). These pathogens have been studies under many types of microscopy to determine the similarities and differences in cell structure and functions. When studied under light microscopy, the contents of Coccidioides immitis cannot by determined; the image shows a possibility of lipids, but the light microscopy is not clear or magnified enough to be definitive (O’Hern & Henry, 633). Coccidioides posadasii, on the other hand, can very easily be observed using light microscopy. A study conducted by Chiung-Yu Hung, and many other scientists, showed many structures of the inoculated Coccidioides posadasii after 32 hours, 96 hours, and 132 hours. After 96 hours, the study showed that Coccidioides posadasii had growth of at least 500 spherules as well as blue-stained bands after 132 hours (Hung et al, 6695). TEM microscopy, or transmission electron microscopy, was also used as a way of studying both Coccidioides posadasii and Coccidioides immitis. Coccidioides posadasii did not show any difference in growth in the endospores; however, it did show the gold particles, used to stain the pathogen, in the cytoplasm and vacuoles of the cells (Mirbod-Donovan et al, 507). Coccidioides immitis, when seen through the TEM microscope, studied only the parasitic phase of the pathogen. Endospores were seen forming in the beginning stages, and arthrospores and chlamydospores were seen forming from mycelium (O’Hern and Henry, 632).
Generally, the reservoirs of pathogens vary widely.

Some are found specifically in the human body and some are found in the environment and will eventually enter the human body. Coccidioides immitis and Coccidioides posadasii are two pathogens that are found in the environment and will eventually enter the human body. Both pathogens are found in the southern United States, Mexico, and Central and South America (Fungal Infections, 8). Coccidioides immitis is found in the lower, arid zone of the United States; specifically, the southwestern states like Arizona, southern California-primarily the San Joaquin Valley, and New Mexico, as well as in Central and South America (Lewis et al, 1). Coccidioides immitis is also found in the soil and is classified as an ascomycete (Lewis et al, 2). Coccidioides posadasii is found in the more central southern United States; specifically, Texas, Arizona, and New Mexico, as well as Mexico, Central America, and South America (Lewis et al, 2). Coccidioides posadasii is also found in soil and classified as an ascomycete (Lewis et al, 2). Once the pathogens have grown to a point of maturity, they can infect the host. Both Coccidioides immitis and Coccidioides posadasii infect humans primarily; these pathogens will also infect other mammals such as cattle and dogs (Kellner et al, 111). Infection of the host can cause many issues in large cattle populations as the cattle are eating and breathing the same things; there is really no way to stop the

spread of this strand of fungal pneumonia without completely moving the cattle populations out of that region of the country. Infection of the host is caused by inhalation of spores (Fungal Infections, 8). Once the spores have been inhaled, the lungs are infected and will begin to slowly lose function without treatment (Kellner et al, 111).
Infection in human hosts are the most easily treated of the mammalian hosts infected.

Infections tend to be mild and may cause flu-like symptoms. Many time, the infection will require an antifungal treatment (Kellner et al, 111). Because of the flu-like symptoms, this disease was fairly difficult to diagnose; many patients died and were thought to have died from the flu. In 1892, the disease was finally discovered, was originally recognized as Coccidioides immitis only, and was treated with antifungal drugs (Cox and Magee, 805). According to the initial, official studies of this disease, patients could live anywhere from four months to nine years. The first two patients were drastically different; patient one had a slowly progressing form of Coccidioidomycosis, the disease caused by both Coccidioides immitis and Coccidioides posadasii. Patient one lived for nine years after the initial diagnosis and never received any antifungal treatment (Cox and Magee, 806). Patient two had a much more rapidly progressing form of Coccidioidomycosis. Patient two lived for only four months and died from the infection caused by the Coccidioides immitis pathogen (Cox and Magee, 806). Patient one made those studying this disease because that the pathogen would be slow acting, so patient two was treated as though the pathogen wouldn’t take full effect for a few years. As stated above, Coccidioidomycosis is the disease caused by Coccidioides immitis and Coccidioides posadasii. Coccidioidomycosis

is commonly known as Valley Fever and can be treated only with antifungal treatments; this disease can take years to show symptoms in human hosts and may remain asymptomatic until the pathogen has infected too much to be treated (Hung et al, 6689). In order for Coccidioidomycosis to evade host detection, the pathogen can mutate during the endosporulation phase of the parasitic cycle. By doing so, the pathogen is allowing the human host cells to believe that it is a part of the normal immune system-this is the main reason why the disease can remain asymptomatic for so long (Hunt et al, 6689). According to Hung and other scientists studying the progression of infection of Coccidioidomycosis, the “mep1 mutant strain result in increased phagocytosis and clearance of the pathogen from infected host tissue,” meaning that this mep1 mutant strain is what allows the pathogen to evade host detection (6701). Coccidioidomycosis could potentially be used as a biothreat. If spread in the general human population, this disease would rapidly infect the majority of people it came in contact with and the toxins could potentially kill at least 50% of the population (Cos and Magee, 808). Alpha and Beta T lymphocytes in the human body could potentially learn to fight off this disease, causing immunity, however studies have shown that this is not yet possible (Cox and Magee, 811).