There are a group of proteins that are made and released by host cells in response to the presence of pathogens. Interferon’s are of many types: IF α, IF β and IF γ.  Emerging viral disease is a major threat to global health. Due to rapid mutation and adaptation, changing environment several new viral diseases are emerging and causing human illness. Cross infection is the transfer of harmful microorganisms from one person to other. The spread of infections can occur between people, pieces of equipment, or within the body

Retroviruses induce diseases that do not fit easily into any of the major categories and different tissues can influence the type of disease that develops the first retrovirus associated with disease was equine infectious anemia virus (EIAV). Anemic cats contain reduced numbers of BFU-E and CFU-E, and FeLV infection suppresses the generation of these precursors in vitro. Endogenous retroviral proteins are acting as auto antigen in liver disease patients. While murine retroviruses are inactivated by human complement and are not capable of causing human disease.

Some infectious diseases can be passed from person to person. Signs and symptoms vary depending on the organism causing the infection. Human Papilloma Virus is the most common sexually transmitted infection. Some types of these viruses can cause genital warts and cancers. Genital warts usually appear as a small bump or group of bumps in the genital area.

Human endogenous retroviruses (HERV) proviruses comprise a significant part of the human genome, with approximately 98,000 ERV elements and fragments making up nearly 8%. Jaagsiekte sheep retrovirus (JSRV) is a beta retrovirus which is the causative agent of a contagious lung cancer in sheep called Jaagsiekte. Koala retrovirus was initially described as a novel endogenous retrovirus found within the koala genome and in tissues as free virions. The murine leukemia viruses are group/type VI retroviruses belonging to the gamma retroviral genus of the Retroviridae family. 

The retroviral genome having the elements needed for reverse transcription was used to perform the other activities of retroviruses. Overall changes in the host cellular proteome upon retroviral infection intensify from the initial entry of the virus to the incorporation of viral DNA into the host genome, and finally to the consistent latent state of infection. 

Several viruses are linked with cancer in humans. As per our growing knowledge the role of viruses as a cause of cancer has led to the development of vaccines to help and prevent certain human cancers. But these vaccines can only protect against infections if they are given before the person is exposed to the cancer-promoting virus. Some of the cancer causing viruses is Hepatitis B virus (HBV) and hepatitis C virus (HCV),

HIV is Sexually transmitted diseases which spread by contact with infected blood or from mother to child transmission during pregnancy, childbirth or breast-feeding. It can take years before HIV weakens the immune system to the point that the person is infected with AIDS. Several major associations in USA working on HIV like UNAIDS, Centers for Disease Control and Prevention, WHO, NIH(National institute of allergy and infectious diseases).There are over 1000’s of association and societies working together to provide shelter, guidance and education. 

In many areas of HIV/AIDS research involve clinical trials. Clinical trials are research studies designed to find out if new drugs, vaccines, or other treatments are safe and if they work in people. Sometimes, it can be hard for patients to learn about opportunities to take part in clinical trials. 

Antiretroviral drugs are the medications for treatment of infection by retroviruses, primarily HIV. Different classes of antiretroviral drugs act at different stages of HIV life cycle. The Combination of several (typically three or four) antiretroviral drugs is known as Highly Active Anti-Retroviral Therapy (HAART).

HIV and AIDS research is a medical research that helps in prevention and treatment of HIV which is an infectious agent that helps in causing AIDS. Recent shows that the hormones namely estrogen and progesterone impacts the transmission of HIV. Examples include HIV vaccines, drug development, and pre exposure prophylaxis. 

The disputes related to antiretroviral drug therapy has been surmounted by adapting the various novel drug delivery methods, which pays pathway for many scientists to prove the efficiency of their techniques. Even though there are certain successful technologies emerging under this field, the progression of vesicular systems like liposomes and Nano sized systems like nanoparticles exhibits superior attention and significance over the other schemes. The formulation design and optimization of analytical techniques requires multidisciplinary research for ultimate marketing of these NDDS products especially for ARV drugs, because of the intricacy of the viral infections. 

Epidemiology is the occurrence of communicable and chronic diseases, principally in the form of epidemics which is caused by microbial infection. Infection is the invasion of foreign microbial organism on our immune system for its survival and growth. Infections are caused by infectious microrganisms including viruses, viroids, prions, bacteria, parasitic roundworms and pinworms, ticks, mites, fleas, and lice, ringworm, and other macroparasites such as tapeworms and other helminths.

People who infected with the human immunodeficiency virus are called as HIV infected people and they abbreviated as PLWHA (People Living With HIV/AIDS). According to the AIDS epidemic update by UNAIDS in 2007, 33.2 million people are infected with HIV/AIDS and more than 68% of infected HIV individuals are living in Sub-Saharan Africa. 

Accurate immune chromatographic assays to detect HIV, hepatitis C virus (HCV) and syphilis antibodies have made home or supervised self-testing possible along with feasibility and excellent test characteristics for HIV, HCV and syphilis POC tests. Several rapid oral HIV tests are now available for purchase along with combined HIV and syphilis tests using a single finger prick blood sample are evolving.