What we say about the diseases that are related with our respiratory system. Is it Influenza or Flu? Or Stomach Flu?

Everyone is aware about the common word of Flu but exactly it means the "death due to respiratory disease". Influenza is caused by an RNA virus of orthomyxoviridae family and it is seasonal epidemics can be categorized in three genera of the virus as Influenza A viruses, Influenza B viruses that infect only humans and Influenza C that infect only humans. Currently, the most common antigenic variants of influenza A virus are H1N1 and H3N2.

Normally, it is spread and transmitted from individual to individual in saliva droplets expelled by coughing. Due to this many symptoms of flu and influenza appears such as, fever headache fatigue, dry cough sore throat, nasal congestion sneezing, irritated eyes, body eyes, extreme coldness.

Mostly it takes one to two weeks to recover but influenza can be deadly for the weak, old or ill person.

Normally cold occurs in the meantime of the year but influenza spreads mostly in the winter season because of the atmospheric fluctuations in northern and Southern Hemisphere regions.

The natural host for influenza virus is aquatic birds. Pandemic influenza often occurs when an avian-adapted virus infects a porcine host, which can be infected by human and avian varieties of influenza A virus. The virus may then recombine within the pig, to form a genetically new virus, which is able to infect humans and be transmitted from person to person.

The current avian flu threat (2005) is due to the H5N1 virus. This virus is currently still avian-adapted and cannot be transmitted from person to person, though it seems to be able to infect humans and cause mortality.

Every national Government is getting the help of anti-viral drugs such as Tamiflu, which can reduce the effects of the virus.