What is flu?..What it is, what it ain't and everything in between.
WHAT IS THE FLU?
Simply put, influenza (a. k.a. the flu) is a common respiratory illness that attacks the nose, throat, bronchi and, in rare cases the lungs. it affects an estimated 10 to 25 percent of Canadians annually. in North America, the risk of infection is greatest during flu season, which runs from November through April, but local outbreaks occur worldwide year-round.
The flu is caused by one of the many influenza viruses, which fall into three groups: A, b and C. each group is further broken down into different strains, such as A(H3N2) or A(H1N1).the genetic makeup of influenza viruses allows for frequent mutation, making it impossible for the human body to sustain immunity over time on its own. Flu vaccines--the only surefire way to protect yourself from infection--are reformulated annually to account for these changes.
Influenza A and b are the most prevalent types and pose the highest risk to humans. As such, they are included in the seasonal flu vaccine each year. influenza C, on the other hand, is less common and causes only mild illness in comparison to A and b. it is not typically included in the vaccine.
The World Health Organization's (WHO) Global influenza Surveillance Network is responsible for recommending the annual flu vaccine. this network of more than 100 National influenza Centres in nearly as many countries constantly monitors which viruses are currently circulating in humans and rapidly identifies new strains. based on its findings, WHO recommends an annual vaccine that targets the most virulent strains.
MORE THAN JUST A COLD...
Although flu symptoms often mirror those of the common cold, the latter are typically milder and come on more slowly. When the flu strikes, it does so with a bang and, more often than not, a fever. both illnesses share many of the same symptoms, including a sore throat, cough and stuffy nose, but a cold rarely presents with a temperature of more than 38 C. body and muscle aches are also more common with the flu.
A CASE OF MISTAKEN IDENTITY
The common cold isn't the only illness masquerading as the flu. Viral gastroenteritis is often referred to as the "stomach flu," despite the fact that the two illnesses have little in common other than a high risk of contagion. Gastroenteritis-- whether caused by rotavirus, Norwalk or another virus--is marked by stomach cramps, diarrhea and vomiting. Although these symptoms can present in children with the flu, they are extremely rare in adults. Fever and body ache--two hallmarks of influenza--are also atypical of gastroenteritis.
PANDEMIC FLU
These days, it's pandemic flu that's on the tip of everyone's tongues. it refers to a new strain of influenza that is able to spread quickly around the globe as humans have little to no immunity against it by virtue of its novelty. Although the flu virus is constantly evolving, people who have had previous bouts of influenza will still usually possess some protection against similar strains of the virus. However, every quarter century or so, a radical enough change occurs such that humans have never experienced anything like it before and are thus completely vulnerable. this was what happened in 2009 when pandemic H1N1, or swine flu, erupted around the world.
AVIAN FLU
Of lesser concern to humans, but worth noting nonetheless, is avian influenza, or bird flu, a type A virus. For most Canadians, the risk of contracting the disease is quite low. it is primarily found in birds and transmitted through their droppings and secretions. However, given the innate mutative ability of flu viruses, there is a chance that avian influenza could mix with a human flu virus and lead to an outbreak of pandemic flu, and thus it is worth our attention. people who handle wild birds are at the highest risk of infection and should take proper precautions when working with fowl.
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Information courtesy of the National Post for public health benefit. Feb. 17. 2020
WHAT IS THE FLU?
Simply put, influenza (a. k.a. the flu) is a common respiratory illness that attacks the nose, throat, bronchi and, in rare cases the lungs. it affects an estimated 10 to 25 percent of Canadians annually. in North America, the risk of infection is greatest during flu season, which runs from November through April, but local outbreaks occur worldwide year-round.
The flu is caused by one of the many influenza viruses, which fall into three groups: A, b and C. each group is further broken down into different strains, such as A(H3N2) or A(H1N1).the genetic makeup of influenza viruses allows for frequent mutation, making it impossible for the human body to sustain immunity over time on its own. Flu vaccines--the only surefire way to protect yourself from infection--are reformulated annually to account for these changes.
Influenza A and b are the most prevalent types and pose the highest risk to humans. As such, they are included in the seasonal flu vaccine each year. influenza C, on the other hand, is less common and causes only mild illness in comparison to A and b. it is not typically included in the vaccine.
The World Health Organization's (WHO) Global influenza Surveillance Network is responsible for recommending the annual flu vaccine. this network of more than 100 National influenza Centres in nearly as many countries constantly monitors which viruses are currently circulating in humans and rapidly identifies new strains. based on its findings, WHO recommends an annual vaccine that targets the most virulent strains.
MORE THAN JUST A COLD...
Although flu symptoms often mirror those of the common cold, the latter are typically milder and come on more slowly. When the flu strikes, it does so with a bang and, more often than not, a fever. both illnesses share many of the same symptoms, including a sore throat, cough and stuffy nose, but a cold rarely presents with a temperature of more than 38 C. body and muscle aches are also more common with the flu.
A CASE OF MISTAKEN IDENTITY
The common cold isn't the only illness masquerading as the flu. Viral gastroenteritis is often referred to as the "stomach flu," despite the fact that the two illnesses have little in common other than a high risk of contagion. Gastroenteritis-- whether caused by rotavirus, Norwalk or another virus--is marked by stomach cramps, diarrhea and vomiting. Although these symptoms can present in children with the flu, they are extremely rare in adults. Fever and body ache--two hallmarks of influenza--are also atypical of gastroenteritis.
PANDEMIC FLU
These days, it's pandemic flu that's on the tip of everyone's tongues. it refers to a new strain of influenza that is able to spread quickly around the globe as humans have little to no immunity against it by virtue of its novelty. Although the flu virus is constantly evolving, people who have had previous bouts of influenza will still usually possess some protection against similar strains of the virus. However, every quarter century or so, a radical enough change occurs such that humans have never experienced anything like it before and are thus completely vulnerable. this was what happened in 2009 when pandemic H1N1, or swine flu, erupted around the world.
AVIAN FLU
Of lesser concern to humans, but worth noting nonetheless, is avian influenza, or bird flu, a type A virus. For most Canadians, the risk of contracting the disease is quite low. it is primarily found in birds and transmitted through their droppings and secretions. However, given the innate mutative ability of flu viruses, there is a chance that avian influenza could mix with a human flu virus and lead to an outbreak of pandemic flu, and thus it is worth our attention. people who handle wild birds are at the highest risk of infection and should take proper precautions when working with fowl.
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Information courtesy of the National Post for public health benefit. Feb. 17. 2020
