In Sewage Effluent and Compost
Fungus in Sludge -- biosolids natural born killers
25. Aspergillus----------------------------------------- Aspergillosis or respiratory
Aspergillosis is an opportunistic infection caused by inhaled spores of the mold
Aspergillus, which invade blood vessels, causing hemorrhagic necrosis and
infarction. Symptoms may be those of asthma, pneumonia, sinusitis, or rapidly
progressing systemic illness. Fungus balls may require surgical resection.
Recurrence is common.
Invasive infections are usually acquired by inhalation of spores or, occasionally, by
direct invasion through damaged skin.
Chronic pulmonary aspergillosis causes cough, often with hemoptysis and
shortness of breath. Invasive pulmonary aspergillosis usually causes rapidly
progressive, ultimately fatal respiratory failure if untreated.
Extrapulmonary invasive aspergillosis begins with skin lesions, sinusitis, or
pneumonia; may involve the liver, kidneys, brain, and other tissues; and is often
Aspergillosis in the sinuses can form an aspergilloma, an allergic fungal sinusitis,
or a chronic, slowly invasive granulomatous inflammation with fever, rhinitis, and
headache. Necrosing cutaneous lesions may overlie the nose or sinuses, palatal or
gingival ulcerations may be present, signs of cavernous sinus thrombosis may
develop, and pulmonary or disseminated lesions may occur. (Merck)
Fungal Necrotizing Cellulitis
Phycomyces and Aspergillus species may cause a gangrenous cellulitis in
compromised hosts. The hallmark of these infections is the invasion of blood
vessels by hyphae, followed by thrombosis and subsequent necrosis extending to
all soft tissue compartments. Spores from these fungi are ubiquitous.
The Phycomyces species are characterized by broad-based nonseptate hyphae.
Rhizopus, Mucor, and Absidia are the major pathogenic genera within the family
Mucoraceae. Serious rhinocerebral, pulmonary, or disseminated infections have
been found in patients with diabetes, lymphoma, or leukemia. Phycomycotic
gangrenous cellulitis usually occurs in patients with severe burns or diabetes. The
characteristic dermal lesion is a black, anesthetic ulcer or an area of necrosis with
a purple edematous margin. There is no gas or exudate, and the infection may
Aspergillus species are characterized histologically by branching septate hyphae.
These fungi can cause serious pulmonary or disseminated infections in
compromised hosts. Aspergillus gangrenous cellulitis may be primary or from a
disseminated infection. The dermal lesion is an indurated plaque that leads to a
necrotic ulcer. Gas and exudate are not present.
(Yanko, 1988) Candida, Cryptocuccus and Trichosporon, Phialophora, Geotrichum,
Trichophyton and Epidermophyton, Dermatophytic fungi
The large and diverse group of microscopic foodborne yeasts and molds (fungi)
includes several hundred species. The ability of these organisms to attack many
foods is due in large part to their relatively versatile environmental requirements.
Although the majority of yeasts and molds are obligate aerobes (require free
oxygen for growth), their acid/alkaline requirement for growth is quite broad,
ranging from pH 2 to above pH 9. Their temperature range (10-35°C) is also broad,
with a few species capable of growth below or above this range.
Both yeasts and molds cause various degrees of deterioration and decomposition
of foods. They can invade and grow on virtually any type of food at any time; they
invade crops such as grains, nuts, beans, and fruits in fields before harvesting and
during storage. They also grow on processed foods and food mixtures. Their
detectability in or on foods depends on food type, organisms involved, and degree
of invasion; the contaminated food may be slightly blemished, severely blemished,
or completely decomposed, with the actual growth manifested by rot spots of
various sizes and colors, unsightly scabs, slime, white cottony mycelium, or highly
colored sporulating mold. Abnormal flavors and odors may also be produced.
Occasionally, a food appears mold-free but is found upon mycological examination
to be contaminated. Contamination of foods by yeasts and molds can result in
substantial economic losses to producer, processor, and consumer.
Several foodborne molds, and possibly yeasts, may also be hazardous to human or
animal health because of their ability to produce toxic metabolites known as
mycotoxins. Most mycotoxins are stable compounds that are not destroyed during
food processing or home cooking. Even though the generating organisms may not
survive food preparation, the preformed toxin may still be present. Certain
foodborne molds and yeasts may also elicit allergic reactions or may cause
infections. Although most foodborne fungi are not infectious, some species can
cause infection, especially in immunocompromised populations, such as the aged
and debilitated, HIV-infected individuals, and persons receiving chemotherapy or