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number of days, dependent on the method used. The rationale behind this requirement becomes clear upon examination of the pathogen content of untreated compost feedstock. TABLE 14 Process for Control of Pathogens in Composted Sewage Sludge. United States Environmentat Protection Agency, 1979. Washington, D.C. A. Processes to Significantly Reduce Pathogens (not the entire list). Using the in -vessel, static aerated pile or windrow composting methods, the solid waste is maintained at minimum operating conditions of 104°F (40°C) for five days. For four hours during this period the temperature exceeds 131 OF (550C). B. Processes to Further Reduce Pathogens (not the entire list). Using the in -vessel composting method, the solid waste is maintained at operating conditions of 131 OF (55°C) or greater for three days. Using the static aerated pile composting method, the solid waste is maintained at operating conditions of 131 OF (55°C) for three days. PATHOGENS Numerous pathogens are present in human septage, manures and mixed municipal solid waste that are capable of causing disease in humans. Pathogens found in sewage sludge and/or mixed municipal solid waste can be divided into four groups: bacteria, viruses, protozoa, and worms. In addition, several pathogenic fungi are also present in composting feedstock. Bacteria The main pathogens of concern often found in sewage sludge are: • Coliform species — cause gastroenteritis, diarrhea; • Vibrio cholerae —causes cholera - symptoms include acute diarrhea - transmitted by sewage and polluted waters or contaminated food and drink; • Salmonella —cause typhoid and food infections - common in sewage; • Bacillus anthracis --causes anthrax — disease of hooved stock but spores can be found in sewage - in man, appears as a skin disease (can be fatal if untreated); and • Mycobacterium tuberculosis - causes - Tuberculosis — from sewage/polluted water — 80,000 reported cases each year. Viruseg Data on the survival of viruses in sewage sludge is less available than that on bacteria due to the difficulty in isolating and culturing them. Among the viruses excreted by humans are: • Poliovirus - causes poliomyelitis, found in effluents of sewage treatment plants; • Hepatitis A - infectious hepatitis can be contracted from contaminated milk, food and water; • Adenoviruses - causes colds, flu and pneumonia; and • Gastroenterins - causes diarrhea, transmitted by water. Protozoa Protozoans cause many human diseases, including dysentery. Protozoans are capable of forming cysts and sometimes are able to survive conditions unfavorable to growth. Intestinal worms and flukes The following worms and/or their eggs are excreted in human feces: • Ascaris - a roundworm, can be transmitted from sewage sludge that is used as a fertilizer; • Necator - a hookworm, can burrow through skin and has been found in sewage farm workers in England; and • Pinworms, whipworms and tapeworms, present in sewage sludge. Ascaris eggs are the most resistant form of any sewage pathogen. Under some conditions these eggs may survive in soil for several years. One study in Germany reported Ascaris eggs to be infective in garden soil for five to seven years. Fungi In addition to the pathogens listed above, approximately 50 species of fungal organisms can also cause disease. These fungi are secondary pathogens — they are not a primary concern to healthy individuals but will affect people who have suppressed immune systems. Individuals who have had or have respiratory infections or prolonged antibiotic or steroid treatment are also susceptible to fungal diseases. A common fungus found in compost and in soil, hay, wood, and foliage is Aspergillus fumigatus. Results of recent studies found a large percentage of compost IV-2