Infectious development

The singularity of MAbs and the ease of mass production appeared to be the answer to rapid development of highly specific immunoassays. Companies were formed to produce MAbs and incorporate them into assays. In fact, such assays have been developed and have proved very successful for infectious diseases, hormones, and other clinical analytes. 

As the result of high specificity and sensitivity, nucleic acid probes are in direct competition with immunoassay for the analytes of some types of clinical analytes, such as infectious disease testing. Assays are being developed, however, that combine both probe and immunoassay technology. In such hybrid probe—immunoassays, the immunoassay portion detects and amplifies the specific binding of the probe to a nucleic acid. Either the probe per se or probe labeled with a specific compound is detected by the antibody, which in turn is labeled with an enzyme or fluorophore that serves as the basis for detection. 

A vaccine is a preparation used to prevent a specific infectious disease by inducing immunity in the host against the pathogenic microorganism. The practice is also called immunization. The first human immunization was performed in 1796 by Edward Jenner in England which led to the discovery of smallpox vaccine. However, classical vaccinology developed 100 years later, after the work by Louis Pasteur demonstrated that microorganisms are causes of diseases. 

Vaccines are used in either the general population of children or adults or for special groups. Recommendations for vaccine usage are made by the Advisory Committee on Immunization Practices (ACIP) of the Centers for Disease Control. The Committee on Infectious Diseases of the American Academy of Pediatrics (Redbook Committee) also makes recommendations for infants through adolescents, and the American Academy of Family Physicians makes recommendations for adults. An excellent review of vaccine history, development, usage, and related regulatory issues is available (2). 

P. J. Baker, ed.. National Institute of Allergy and Infectious Diseases, The Jordan Report, Accelerated Development of Vaccines, 1993, NIH, Bethesda, Md. 

Viruses are small infectious agents composed of a nucleic acid genome (DNA or RNA) encased by structural proteins and in some cases a lipid envelope. They are the causative agents of a number of human infectious diseases, the most important for public health today being acquired immunodeficiency syndrome (AIDS), hepatitis, influenza, measles, and vituses causing diarrhoea (e.g., rotavirus). In addition, certain viruses contribute to the development of cancer. Antiviral drugs inhibit viral replication by specifically targeting viral enzymes or functions and are used to treat specific virus-associated diseases. 

A large and rapidly growing number of clinical trials (phase I and phase II) evaluating the potential of DNA vaccines to treat and prevent a variety of human diseases are currently being performed ( http // clinicaltrials.gov) however, there is yet no licensed DNA vaccine product available for use in humans. The clinical trials include the treatment of various types of cancers (e.g., melanoma, breast, renal, lymphoma, prostate, and pancreas) and also the prevention and therapy of infectious diseases (e.g., HIV/ABDS, malaria, Hepatitis B vims, Influenza vims, and Dengue vims). So far, no principally adverse effects have been reported from these trials. The main challenge for the development of DNA vaccines for use in humans is to improve the rather weak potency. DNA vaccines are already commercially available for veterinary medicine for prevention of West Nile Vims infections in horses and Infectious Hematopoetic Necrosis Vims in Salmon. 

Several TLR-4 adjuvants for vaccines have been developed to date. An example of these is monopho-sphoryl lipid A (MJPL) a modified version of lipid A found in LPS [4]. It has been used extensively in clinical trials as it is far less toxic than LPS. It is hoped to use MPL in vaccines against infectious diseases, allergies and cancer. Derivatives of MPL have now been... 

In infectious disease compounds such as ANA975 (phase I trials) and Resiquimod (phase II trails) have been developed to target Hepatitis C and genital herpes, respectively. DRS954 is a TLR-7 and 9 antagonist in pre-clinical trials for Systemic Lupus Erythematosus (SLE). 

Very little evidence associating water scarcity and an increase in outbreaks of faecal-oral water-borne infectious diseases exists in developed countries. A recent retrospective study performed in England provides some evidence that both low rainfall and heavy rain precede many drinking water outbreaks [3]. Yet, as stated earlier in this review, the situation is potentially different in developing countries [5-7, 9-12], where water scarcity, including droughts, leads to different circumstances that have a clear incidence in the occurrence of both water-borne and water-washed infectious diseases. 

There are some descriptions of water-borne outbreaks, or even small epidemics of acute gastroenteritis (diarrhoea), cholera and hepatitis E associated with catastrophic floods that occurred in developing countries, such as Sudan [34, 35], Nicaragua [36], Mozambique [37] and West Bengal [37]. On the contrary, no changes in the base-line outbreak incidence have been reported in developed countries after major floods [37, 38]. When infrastructures and water management are adequate, outbreaks of faecal-oral water-borne infectious diseases do not follow flood events, even in the case where water flooding has compromised the security of water facilities [37]. 

Initially, it was assumed that the HlV-1 population is infinite, evolution is deterministic, and antiretroviral resistance development is definite (Coffin 1995). However, our research amongst others has demonstrated that the effective population size, defined as the average number of HIV variants that produces infectious progeny is relatively small (Leigh Brown 1997 Leigh Brown and Richman 1997 Nijhnis et al. 1998). This can be explained because the majority of virus particles that are produced harbor deleterious mutations resulting in noninfectious virus. Also limited target cell availability and inactivation of potentially infectious viruses by the host... 

P. acnes is an anaerobic diphteroid that populates the androgen-stimulated sebaceous follicles and is a normal constituent of the cutaneous microflora even if acne is not infectious, the commensal P. acnes acts in acne pathogenesis. Three pieces of evidence support the role of P. acnes in acne 1) higher counts of P. acnes in individuals with acne than in those without acne 2) correlation between the reduction of P. acnes counts and the clinical improvement of the disease and 3) correlation between development of acne and presence of antibiotic-resistant P. acnes organisms. P. acnes products mediate the formation of comedones and contribute to their rupture, leading to extrusion of... 

The terms allergy and atopy are in close proximity of our lives in the new millennium since our lifestyles have enormously changed. Encounters with various new molecules in air, water and diet, living in a more polluted world with less exposure to infections, and infectious agents are supposed to be the major causative factors added to the genetic propensity of developing IgE antibodies responsible for symptoms and... 

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