Infectious organisms

Decontamination is a procedure to render safe for handling, disposal, or the subsequent processing of an article that may contain a large amount of potentially infectious organisms. Decontamination and sterilization are similar procedures, except that in the former case the bioburden is higher. In both cases, all organisms present are destroyed. However, decontamination is not expected to result reHably in the 10 probabiHty of microbial survival, as in sterilization, because of the higher bioburden. Decontamination may include sanitization and disinfection steps, but it most frequentiy involves sterilization... 

Teclmiques such as filtration may remove infectious organisms from water. They... 

IFNs are natural glycoproteins produced by the cells of most vertebrates in response to the challenge by foreign agents, such as infectious organisms (viruses, bacteria, fungi, and parasites), and by tumor cells. IFNs can be produced by cells of the innate and adaptive immune systems and by non-immune cells such as fibroblasts and epithelial cells. 

Trimethoprim-sulfamethoxazole, amoxicillin, first-generation cephalosporins, and erythromycin are not recommended due to susceptibility and resistance patterns of the likely infectious organisms. 

Worldwide, tuberculosis (TB) kills about 2 million people each year, more than any other infectious organism. TB is caused by Mycobacterium tuberculosis, it presents either as latent TB infection (LTBI) or as progressive active disease.1 The latter typically causes progressive destruction of the lungs, leading... 

Enyzme catalysis is thus essential for all life. Hence the selective inhibition of critical enzymes of infectious organisms (e.g., viruses, bacteria, and multicellular parasites) is an attractive means of chemotherapeutic intervention for infectious diseases. This strategy is well represented in modem medicine, with a significant portion of antiviral, antibiotic, and antiparasitic drugs in clinical use today deriving their therapeutic efficacy through selective enzyme inhibition (see Table 1.1 for some examples). 

Last under this heading, for intact infectious organisms to be used directly in humans, assessment of pathogenicity to the range of individuals that make up our populations is needed, as well as consideration of the possibility of reversion to a wild and more dangerous strain, the hazard of an allergenic reaction to the organism (e.g., vaccinia) and the possibility of spread from subject to subject in a naive or incompletely immune population. 

The immune system is divided into two defense mechanisms nonspecific, or innate, and specific, or adaptive, mechanisms that recognize and respond to foreign substances. Some of the important cellular components of nonspecific and specific immunity are described in Table 15.4. The nonspecific immune system is the first line of defense against infectious organisms. Its cellular components are the... 

Exposures to ozone for a few hours result in a marked increase in the susceptibility of animals to controlled doses of infectious organisms introduced into the lung. This is the most sensitive test of any yet reported significantly increased susceptibility of mice to one microorganism occurred after exposure to ozone at a concentration as low as 0.08 ppm. 

In contrast to humans, bacteria have the biochemical ability to synthesize folic acid from simpler molecules. Here we have a clear biochemical difference between human beings and infectious organisms that we can exploit to our benefit. The reaction catalyzed by an enzyme known as dihydropteroate synthetase, in which a complex heterocycle is linked to p-aminobenzoic acid, is key. Now recognize the structural similarity between sulfanilamide, or other sulfonamides, and p-aminobenzoic acid ... 

With the quinoline antibiotics, we have another variation on the theme already developed exploitation of a biochemical difference between an infectious organism and its host. In this case, the difference is in the nature of an enzyme involved in nucleic acid replication, as developed below. 

Steam sterilization is limited in the types of medical waste it can treat, but is appropriate for laboratory cultures and/or substances contaminated with infectious organisms. The waste is subjected to steam in a sealed, pressurized chamber. The liquid that may form is drained off to the sewer or sent for processing. The unit is then reopened after a vapor release to the atmosphere, and the solid waste is removed for further processing or disposal. One advantage of steam... 

Some of the other organisms which cause major health problems around the world and which are found in seafoods are diphyllobothriasis, anisakiasis, heterophyiasis and chlonorchiasis. These infectious organisms can be retarded or controlled by precautiaiary storage and preparation techniques (22). 

The potential for spreading disease organisms from animals to humans and vice versa is not obvious to most people. These so-called zoonotic diseases include agents of all the major categories of infectious organisms viruses, bacteria, parasites, and fungi. Infectious hazards are insidious, and therefore safe practices should be habitual and strictly enforced. All employees should be instructed as to the nature of these hazards and the means to take to protect animals and themselves from infection. Employees should also be instructed to report all personal illnesses to their supervisor. The supervisor can then determine whether or not it would be appropriate for the employee to have contact with test and control articles and test systems. 

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