Pharmaceutical measures are effective but may not be available in the early stages of an outbreak.In health care settings, infected individuals may be cohorted or assigned to individual rooms. Protective clothing such as masks, gloves, and gowns is recommended when coming into contact with infected individuals if there is a risk of exposure to infected bodily fluids. Keeping patients in negative pressure rooms and avoiding aerosol-producing activities may help, but special air handling and ventilation systems are not considered necessary to prevent the spread of influenza in the air. In residential homes, new admissions may need to be closed until the spread of influenza is controlled. When discharging patients to care homes, it is important to take care if there is a known influenza outbreak.Since influenza viruses circulate in animals such as birds and pigs, prevention of transmission from these animals is important. Water treatment, indoor raising of animals, quarantining sick animals, vaccination, and biosecurity are the primary measures used. Placing poultry houses and piggeries on high ground away from high-density farms, backyard farms, live poultry markets, and bodies of water helps to minimize contact with wild birds. Closure of live poultry markets appears to the most effective measure and has shown to be effective at controlling the spread of H5N1, H7N9, and H9N2.
As early as 1504, influenza began to mean a "visitation" or "outbreak" of any disease affecting many people in a single place at once. During an outbreak of influenza in 1743 that started in Italy and spread throughout Europe, the word reached the English language and was anglicized in pronunciation. Since the mid-1800s, influenza has also been used to refer to severe colds. The shortened form of the word, "(the) flu", is first attested in 1839 as flue with the spelling flu first attested in 1893. Other names that have been used for influenza include epidemic catarrh, la grippe from French, sweating sickness, and, especially when referring to the 1918 pandemic strain, Spanish fever. Research
Influenza research is wide-ranging and includes efforts to understand how influenza viruses enter hosts, the relationship between influenza viruses and bacteria, how influenza symptoms progress, and what make some influenza viruses deadlier than others. Non-structural proteins encoded by influenza viruses are periodically discovered and their functions are continually under research. Past pandemics, and especially the 1918 pandemic, are the subject of much research to understand flu pandemics. As part of pandemic preparedness, the Global Influenza Surveillance and Response System is a global network of laboratories that monitors influenza transmission and epidemiology. Additional areas of research include ways to improve the diagnosis, treatment, and prevention of influenza. Existing diagnostic methods have a variety of limitations coupled with their advantages. For example, NATs have high sensitivity and specificity but are impractical in under-resourced regions due to their high cost, complexity, maintenance, and training required.