Viral and immune mediated disorders of the nervous system are among the foremost difficult neurological disorders. The most common neuroimmune disorder is multiple sclerosis; and HIV is the most common viral infection of the nervous system. Common to disorders is the progressive loss of neurons, resulting in significant cognitive and motor dysfunction. The brain is a direct target for certain infections, and may also be indirectly affected by systemic bacterial, viral, or parasitic infections. Certain pathogens, like the human immunodeficiency virus (HIV), syphilis, West Nile Virus, Borrelia burgdorferi (resulting in Lyme disease), and other viral brain infections occur in healthy persons. Other infections, such as fungal infections or rarer parasites tend to most commonly affect people with reduced immune systems from cancer, chemotherapy, immunosuppressive therapy, or transplantation. Several infectious diseases can affect the brain, spinal cord, peripheral nerves, neuromuscular junction (the connection between the nerve ending and the muscle), or the muscles.

The battle between pathogens and therefore the host immune defenses has raged for thousands of years. The system has developed a range of approaches to controlling viral and bacterial infection, that vary  from direct killing of pathogen to elaborating cytokines that inhibit replication. Pathogens have countered by developing a range of immune evasion mechanisms that inhibit cytokine function and inhibit immune recognition of infected cells. Immunology describes how the body copes with microbial, viral, or parasitic infections, cancer, and other diseases. It needs expertise and analysis from the level of the molecules and cells of the immune system all the way up to disease dynamics in populations and ecosystems. Infectious and immune-mediated diseases currently under study include HIV/AIDS, Tuberculosis, Chagas, Malaria, Pneumonia, Enteric Diseases, Inflammatory Bowel, and Autoimmune diseases. Additional immunologic studies focus on genetic regulation of the immune response, the interplay between the innate immune system and intestinal microbial communities, the function and regulation of T-cell-derived cytokines and cytokines involved in the regulation of inflammation.

Bacterial pathogenesis is the process by which bacteria cause infectious diseases. Most diseases are caused by multiple processes. Most maladies are brought on by numerous procedures. One of the bacterial sicknesses with the most elevated infection weight is tuberculosis, brought about by the bacterium Mycobacterium tuberculosis. Pathogenic microscopic organisms add to other universally critical infections, for example, pneumonia, which can be brought about by microorganisms, for example, Streptococcus and Pseudomonas, and foodborne ailments, which can be created by microbes, for example, Campylobacter, and Salmonella. Pathogenic microscopic organisms additionally cause infections such as tetanus, typhoid fever, diphtheria, and leprosy. Pathogenic microscopic organisms are additionally the reason for high baby death rates in creating nations. Koch's postulates are the standard to establish a causative relationship between a microbe and a disease.

Viral pathogenesis is the procedure by which infections produce disease in the host. The elements that decide the viral transmission and advancement of illness in the host include complex and dynamic connections between the infection and the susceptible host. Infections cause malady when they break the host's essential physical and normal defensive barriers; evade local, tissue, and immune defences; spread in the body; and destroy cells either specifically or through observer safe and provocative reactions. Viral pathogenesis can be partitioned into a few phases, including transmission and passage of the infection into the host, spread in the host, tropism, virulence, patterns of viral infection and disease, host factors, and host defence. An important part of viral pathogenesis is viral the study of disease transmission since it permits doctors to contemplate the dissemination of determinants of sickness in human populations.

Fungal pathogenesis is the procedure by which organisms contaminate and cause malady in a host. Not all organisms are pathogens and have the capacity for pathogenesis, otherwise called virulence. We all have regular contact with fungi. They are so generally circulated in our surroundings that a huge number of contagious spores are breathed in or ingested each day. Progressive systemic fungal infections pose some of the most difficult diagnostic and therapeutic problems in infectious disease, particularly among immune compromised patients to whom they are a noteworthy risk. Compared with bacterial, viral, and parasitic disease, less is known about the pathogenic mechanisms and virulence factors related in fungal infections. Analogies to bacterial illnesses come the nearest due to the evident significance of adherence to mucosal surfaces, obtrusiveness, extracellular items, and cooperation with phagocytes.

An antimicrobial is an agent that kills or inhibits the growth of microorganisms. The microbial agent may be a chemical compounds or physical agents. Antimicrobial medicines may be sorted in keeping with the microorganisms they act primarily against. As an example, antibiotics are used against bacteria and antifungals are used against fungi. They can also be classified according to their function. Agents that kill microbes are called microbicidal, whereas those who simply inhibit their growth are called biostatic. The utilization of antimicrobial medicines to treat infection is known as antimicrobial chemotherapy, whereas the utilization of antimicrobial medicine to prevent infection is known as antimicrobial prophylaxis. These agents interfere with the growth and reproduction of causative organisms like bacteria, fungi, parasites, virus etc. The main categories of antimicrobial agents are disinfectants, which kill a wide range of microbes on non-living surfaces to prevent the spread of illness, antiseptics which are applied to living tissue and help to reduce infection throughout surgery, and antibiotics that destroy microorganisms inside the body.

Medical Microbiology is the branch of medicine involved with the prevention, diagnosis, and treatment of infections and communicable diseases. There are four kinds of microorganisms that cause infectious disease: bacteria, fungi, parasites and viruses, and one type of infectious protein called prion. A medical life scientist studies the characteristics of pathogens, their modes of transmission, mechanisms of infection and growth. Medical microbiologists usually serve as consultants for physicians, providing identification of pathogens and suggesting treatment options. The interaction between a pathogen and its host cell has become increasingly important to understand and interfere with diseases caused by microbial pathogens.

Clinical Microbiology mainly deals with the lab determination of human and animal infections and the role of the lab in both the administration of infectious diseases and the clarification of the study of disease transmission of diseases. Bacterial, protozoan, and infectious agent pathogens have advanced a decent type of instruments to discover themselves inside the host and pick up supplements that conjointly cause mischief and ailment. Clinical microbiologist contemplates the non-pathogenic species to figure out if their properties can be utilized to create anti-infection agents or other treatment strategies.

Genetics is the science of heredity and genetic information in a cell. Genetic information pasess from cell to cell as well as from genereation to generation.Genetic information is stored in the form of either DNA or RNA in all the lining organisms. Microbial genetics is the study of genome or the genetic material of microorganisms. Most of the bacteria and viruses have RNA as the genetic material. Retroviruses are the viruses with DNA as genetic material and caused AIDS in humans. Microbial genetics plays a crucial role in field of molecular and cell biology and profound applications in medicine, food, agriculture and pharmaceutical industries. It also involves the transmission of hereditary characters in microbes.

Infectious diseases are disorders caused by organisms for example, microscopic organisms, viruses, fungi or parasites. Many organisms live in and on our bodies. Some infectious diseases can be passed from individual to individual. Some are transmitted by bites from insects. Others are obtained by ingesting defiled nourishment or water or being exposed to organisms in the environment. Signs and side effects differ contingent upon the living being bringing about the contamination, yet frequently incorporate fever and exhaustion. Mild infections may react to rest and home cures, while some life-debilitating diseases may require hospitalization. Many infectious diseases, for example, measles and chickenpox, can prevent by vaccines.  Continuous and intensive hand-washing likewise shields you from most infectious diseases. Hosts can fight infections using their immune system. Mammalian hosts react to infections with an innate response, followed by an adaptive response.

A vaccine is a biological preparation that gives dynamic procured safety to a specific malady.  A vaccine typically contains an agent that look like a disease-causing micro-organism and is often made from weakened or killed forms of the microbe, its toxins or one of its surface proteins. The agent releases the body's immune system to recognize the agent as a threat, destroy it, and keep a record of it, so that the immune system can more easily recognize and destroy any of these micro-organisms that it later encounters. A drug may be classified by the chemical type of the active ingredient or by the way it is utilized to treat a specific condition. Each drug can be classified into one or more drug classes.

 Diagnostic microbiology deals with the latest developments in clinical microbiology and the diagnosis and treatment of infectious diseases. It relates with bacteriology, immunology, infectious diseases, mycology, parasitology, and virology. The analysis of a microbial disease starts with an appraisal of clinical and epidemiologic elements, prompting the plan of a symptomatic theory.  Diagnostic microbiology can also be a part of developing a treatment plan. Organisms, for example, microbes and protozoans assume a part in numerous illness forms. A considerable lot of the procedures like microscopy, immunological tests, radiology, biomarker tests, ELISA, serology tests, immunization vectors are the major demonstrative tests that are as of now being used. Many microbes have developed resistance to medications. Thus, it is important for the researchers to discover more brilliant methods for diagnosing these microorganisms and their pathogenic instruments.

Immunodiagnostics is a diagnostic process that uses an antigen-antibody reaction as their primary source of detection. To detect the disease caused by infectious microorganisms, immunoassays have been developed. These biochemical and serological methods depend on the discovery of antibodies produced against infectious agent, a microbe, or non-microbial antigen. Serological tests are performed on blood serum, and body liquids, for example, semen and salivation. It’s usually refers to the diagnostic identification of antibodies in the serum or the detection of antigens of infectious agents in serum. Enzyme-linked immune sorbent assay is a measurement technique for identification an antigen immobilized on a strong surface and uses a particular immune response with a covalently coupled compound. The measure of immune response that ties the antigen is relative to the measure of antigen present, which is dictated by spectrophotometry technique.  Diagnostic immunology created for progression in mechanized fields. Diagnostic immunology takes a shot at the immunization field for security against HIV infection.

The infections caused by germs and which may infect any part of the body are called infectious diseases. Infection prevention and management demands a basic understanding of the epidemiology of diseases; risk factors that increase patient susceptibility to infection; and the practices, procedures and treatments that may result in infections. Infection prevention and management is useful to prevent the transmission of infectious diseases. Some infectious diseases are often prevented by avoiding direct contact with the contagious person.  Infections can even be controlled and prevented by making public awareness on various infectious diseases and their outbreaks.