The first and foremost efforts to develop influenza vaccines were initiated soon after influenza A and B viruses were identified as the etiologic agents of clinical influenza. The United States in 1945 has approved the first commercial vaccines using whole-inactivated influenza virus for use. The flu vaccine is an annual vaccination using a vaccine to protect against the highly variable influenza virus that is specific for a given year. Risk management and effectiveness of vaccines are important for public health.

Influenza antibodies are immunizations that secure against Influenza. A yearly occasional Influenza antibody (either the Influenza shot or the nasal Influenza immunization) is the most ideal approach to decrease the risk of infection. Influenza immunizations create antibodies in the body around two weeks after inoculation which is a rough estimate of its incubation period.

Influenza outbreaks and epidemics constitute ongoing risks to global human public health. Recently, human infections with A/H5N1 avian influenza viruses have intensified the potential for the emergence of an influenza A virus with pandemic potential. Laboratory identification of human influenza virus infections is commonly performed using virus isolation in cell culture, direct antigen detection, or detection of influenza-specific RNA by reverse transcriptase-polymerase chain reaction (RT-PCR). In recent years commercial influenza rapid diagnostic tests have become available which are antigen detection tests that produce results within 30 minutes. They can provide results in a clinically relevant time frame to complement the use of antiviral medications for treatment and chemoprophylaxis of Influenza

Flu epidemic occurs when flu activity is higher than CDC-defined baseline value. The baseline is the level of flu activity during months when flu viruses are not widely circulating spreading in people. Epidemics of influenza are not uncommon and can occur any time this is in contrast to pandemic influenza

Zoonotic disease is a disease that can be spread amongst animals and people. Zoonotic disease can be brought about by infections, microbes, parasites, and organisms. Researchers estimate that more than 6 out of each 10 infection illnesses in people are spread from animals.

Zoonotic diseases are diseases transmitted from animals to humans. Zoonotic diseases come in the form of bacteria, viruses, fungus, or parasites. There are over 250 zoonotic organisms, with only about 40 being transmitted from dogs and cats. Whatever remains of the zoonotic animals are transmitted from bird, reptiles, farm animals, wildlife, and other mammals Individuals who have a debilitated or a bargained safe.

Zoonotic diseases are naturally transmitted between vertebrate animals and humans. A zoonotic agent may be a bacterium, virus, fungus or other communicable disease agent. Animal infections/ zoonosis are important threat to human health since the emergence of human diseases is dominated by zoonotic pathogens.   Zoonotic infections cause diseases like Lyme and rabies.

Influenza causes an acute infection of the host and initiates a cascade of immune reactions activating almost all parts of the immune defense system. Most of the initial innate response, including cytokine release (IFNα/β), influx of neutrophil granulocytes or natural killer cells, and cell activation, is responsible for the acute onset of the clinical symptoms. Influenza viruses, however, encode in the non-structural protein 1 (NS1) mechanisms to evade and antagonize the IFN α/β response. NS1 is likely to sequester viral dsRNA which prevents recognition of this dangerous molecule by cellular sensors which would otherwise trigger IFN α/β release. Evasion from the host immune response requires a lot of viral proteins to associate with and inhibit cellular proteins with antiviral functions. Because viral genomes are typically 10,000 to 100,000 times smaller than the human genome, most or all steps of virus infection depend on exploiting host gene functions. Identifying such host genes is currently a crucial frontier in understanding infection. These host genes also are attractive targets for viral control, since they are not subject to the high mutation rates by which viruses escape from antivirals targeted against their own genes. 

Animal influenza viruses are different from human seasonal influenza virus and do not easily transmits to humans.  Zoonotic influenza viruses - animal influenza viruses that may occasionally infect humans through direct or indirect contact - can cause disease in humans ranging from a mild illness to death.

Birds are the natural parasites for avian influenza viruses. After an outbreak of A(H5N1) virus in 1997 in poultry in Hong Kong SAR, China, since 2003, this avian and other influenza viruses have spread from Asia to Europe and Africa. In 2013, human infections with the influenza A(H7N9) virus were reported in China.

Universally, influenza activity has diminished from its peak of flu action. The WHO's Global Influenza Program (GIP) gives worldwide measures to influenza surveillance. Furthermore GIP gathers and examinations virological and epidemiological influenza surveillance information from around the globe. The standard sharing of value quality influenza surveillance and monitoring data by nations permits WHO to: give countries, areas and territories with data about flu transmission in different parts of the world to permit national approach creators to better get ready for up and coming seasons; 

Vaccinations against influenza are recommended by the World Health Organization for those at high risk. The Influenza vaccine is effective against three or four types of influenza. Outbreaks of influenza occur every year and typically reach epidemic levels at some part of the season. Influenza viruses are constantly changing; they can change from one season to the next and can even change within the course of one flu season. Resistance of influenza A viruses to antiviral drugs can occur spontaneously or emerge during the course of antiviral treatment or antiviral exposure. Antiviral medications currently recommended include oseltamivir (Tamiflu®) and zanamivir (Relenza®). The vast majority of currently circulating influenza viruses is sensitive to these medications. Getting a yearly seasonal flu vaccination is the first and most important step in preventing the flu. The vaccine protects against an influenza A (H1N1) virus, an influenza A (H3N2) virus, and one or two influenza B viruses (depending on the vaccine). CDC recommends that everyone 6 months of age and older get vaccinated each year. Viral infections of the respiratory tract impose a high burden on society. In the last half of the 20th century, efforts to prevent or minimize their impact centred on the use of influenza vaccines. Each year enormous effort goes into producing that year's vaccine and delivering it to appropriate sections of the population.