What Is Avian Or Bird Flu
Bird flu, or avian influenza, is an infectious disease of birds caused by type A strains of the influenza virus. Bird flu epidemics have occurred worldwide.
Bird flu is a leading contender to be the next pandemic flu bug because it has caused an unprecedented epidemic in poultry and wild birds across Asia and Eastern Europe. Still, no one knows for sure whether this will cause the next human flu pandemic.
For in-depth information, see WebMD’s Understanding Avian or Bird Flu.
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Antigenic Drift And Shift
Two key processes that influenza viruses evolve through are antigenic drift and antigenic shift. Antigenic drift is when an influenza virus’s antigens change due to the gradual accumulation of mutations in the antigen’s gene. This can occur in response to evolutionary pressure exerted by the host immune response. Antigenic drift is especially common for the HA protein, in which just a few amino acid changes in the head region can constitute antigenic drift. The result is the production of novel strains that can evade pre-existing antibody-mediated immunity. Antigenic drift occurs in all influenza species but is slower in B than A and slowest in C and D. Antigenic drift is a major cause of seasonal influenza, and requires that flu vaccines be updated annually. HA is the main component of inactivated vaccines, so surveillance monitors antigenic drift of this antigen among circulating strains. Antigenic evolution of influenza viruses of humans appears to be faster than influenza viruses in swine and equines. In wild birds, within-subtype antigenic variation appears to be limited but has been observed in poultry.
What Should A Person Do Who Thinks They Have Influenza
There are two principles: 1. Look after yourself and 2. Dont infect others.
The customs vary with the country. In some countries most people expect to see a doctor while in other countries it is not always thought necessary to actually see a doctor unless the person seems very ill or is in a risk group. People with chronic or long-standing illness may need medical attention earlier and quickly.
The best advice is for the person to go home, use handkerchiefs properly , wash his or her hands frequently, do not share towels, rest, drink plenty of fluids and take medicines that will reduce the temperature and the aching . If it is necessary to have people about him or her at home he or she might consider wearing a simple disposable mask.
Most influenza illnesses are self-limiting and may be caused either by influenza or other viruses/pathogens. It is best to treat the infection at home until the person is well enough to return to normal activities.
However advice from the persons doctor or nurse must be sought quickly if symptoms become more severe or last more than about a week.
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Classification Of Influenza Viruses
Influenza is caused by any of several closely related viruses in the family Orthomyxoviridae . Influenza viruses are categorized as types A, B, C, and D. These major types generally produce similar symptoms but are completely unrelated antigenically, so that infection with one type confers no immunity against the others. The A viruses cause the great influenza epidemics, and the B viruses cause smaller localized outbreaks. The C viruses cause only mild respiratory illness in humans. Influenza D viruses are not known to infect humans and have been observed only in pigs and cattle.
Influenza A viruses are classified into subtypes, and both influenza B and subtypes of influenza A are further divided into strains. Subtypes of influenza A are differentiated mainly on the basis of two surface antigens hemagglutinin and neuraminidase . Examples of influenza A subtypes include H1N1, H5N1, and H3N2. Influenza B viruses are subdivided into two major lineages, B/Yamagata and B/Victoria. Strains of influenza B and strains of influenza A subtypes are further distinguished by variations in genetic sequence.
How Is The Flu Diagnosed

Often, how a child looks is enough for health care providers to diagnose the flu. Kids who have it usually look ill and miserable.
Other infections can cause symptoms similar to the flu. So if health care providers need to be sure that someone has influenza, they might do a test. They’ll take a sample of mucus by wiping a long cotton swab inside the nose or throat. Results might be ready quickly, or can take longer if the test is sent to a lab.
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How Infectious Is Influenza And How Is It Spread
Among viruses that infect humans influenza is moderately infectious. On average an infectious person will infect another one to two non-immune people. The viruses are mostly passed on in one of two ways. Firstly by people breathing in the larger droplets coming from infectious people coughing or sneezing. If the infected person doesnt cover his or her mouth and nose people within a range of three meters can be infected. That is why its so important that a person covers his or her mouth and nose when he or she sneezes. Smaller droplets and aerosols seem to be less liable to carry the virus. Because only the larger droplets are infectious it is generally only people close to an infectious person who are at risk.
Influenza infection can also be spread by direct contact of the mucous membranes of the nose, mouth and throat with virus, for example from the hands of infectious people who have rubbed their noses. That is why hand-washing and proper use of disposable handkerchiefs are important.
In hospital some medical procedures like intubation can produce infectious aerosols and fine droplets which may have the virus. That is one reason why doctors and nurses take more protective precautions and wear special masks in hospitals.
What Are The Symptoms Of Influenza A
If you have influenza A, you will have some or all of these symptoms:
- sore throat and cough
Children may also have abdominal pain, nausea and vomiting.
Influenza A is a bit like a very bad cold, but a cold doesn’t usually cause aches and pains or a high fever.
If your symptoms get worse instead of better, it’s best to see a doctor. You should also get help straight away if you feel chest pain, you are short of breath, dizzy or confused, or you are vomiting a lot.
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S For Removal And Inactivation Of The Infectious Agent
Influenza viruses belong to the group of enveloped viruses and are, therefore, inactivated by lipid solvents which are also used e.g. in S/D methods. Transmission of influenza viruses by plasma derivatives can therefore be ruled out, above all thanks to the use of physical and chemical depletion and inactivation steps during manufacture .
Patients With Uncomplicated Seasonal Influenza:
Patients that are not from a high risk group should be managed with symptomatic treatment and are advised, if symptomatic, to stay home in order to minimize the risk of infecting others in the community. Treatment focuses on relieving symptoms of influenza such as fever. Patients should monitor themselves to detect if their condition deteriorates and seek medical attention Patients that are known to be in a group at high risk for developing severe or complicated illness, should be treated with antivirals in addition to symptomatic treatment as soon as possible.
Patients with severe or progressive clinical illness associated with suspected or confirmed influenza virus infection should be treated with antiviral drug as soon as possible.
- Neuraminidase inhibitors should be prescribed as soon as possible to maximize therapeutic benefits. Administration of the drug should also be considered in patients presenting later in the course of illness.
- Treatment is recommended for a minimum of 5 days, but can be extended until there is satisfactory clinical improvement.
- Corticosteroids should not be used routinely, unless indicated for other reasons as it has been associated with prolonged viral clearance, immunosuppression leading to bacterial or fungal superinfection.
- All currently circulating influenza viruses are resistant to adamantane antiviral drugs , and these are therefore not recommended for monotherapy.
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How Long Someone Can Spread The Virus
Similarities:
For both COVID-19 and flu, its possible to spread the virus for at least 1 day before experiencing any symptoms.
Differences:
If a person has COVID-19, they could be contagious for a longer time than if they had flu.
Most people with flu are contagious for about 1 day before they show symptoms.
Older children and adults with flu appear to be most contagious during the initial 3-4 days of their illness but many people remain contagious for about 7 days.
Infants and people with weakened immune systems can be contagious for even longer.
COVID-19
How long someone can spread the virus that causes COVID-19 is still under investigation.
Its possible for people to spread the virus for about 2 days before experiencing signs or symptoms and remain contagious for at least 10 days after signs or symptoms first appeared. If someone is asymptomatic or their symptoms go away, its possible to remain contagious for at least 10 days after testing positive for COVID-19. People who are hospitalized with severe disease and people with weakened immune systems can be contagious for 20 days or longer.
Who Is More Likely To Get Very Sick With The Flu
Below is a list of groups of people who may get very sick if they have the flu. It is important that they, and the people around them, get a flu shot.
- People with lung disease like asthma
- People of all ages with ongoing medical conditions like diabetes, heart disease, kidney or liver disease, blood cell disease including sickle cell, or neurological diseases that affect swallowing or breathing
- Pregnant women and women who have given birth within 2 weeks
- Children younger than 5 years, especially those younger than 2 years
- Adults age 50 years and over
- People with weak immune systems
- Household contacts and caregivers of children younger than 5 years and adults aged 50 years and older, with particular emphasis on vaccinating contacts of children aged younger than 6 months and
- Household contacts and caregivers of people with medical conditions that put them at higher risk for severe complications from influenza.
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What Is The Difference Between Influenza Epidemics And Pandemics
Pandemics are worldwide outbreaks of a disease and are estimated to occur on average once every 50 years for influenza. Epidemics happen much more frequently, and seasonal influenza appears annually in most parts of the world. The influenza pandemic of 191819 is the most destructive influenza outbreak in history, which resulted in an estimated 25 million deaths.
Cold And Flu Season Precautions: What To Do

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Is It The Flu A Cold Or The Omicron Variant How To Know And When To Get Tested For Covid
The coronavirus pandemic in Florida is an evolving news story so some information in this article could be out of date. To stay connected with our comprehensive coverage of COVID-19 in Florida, .
Sneezing? Feeling congested? Coughing? Are these signs of flu season, a cold or allergies, or are they symptoms of COVID-19’s rapidly spreading omicron variant?
Without testing, it is difficult to determine whether the congestion is more than the flu, but either way, don’t panic, say medical experts, just take proper precautions.
“If you feel sick, dont diagnose yourself,” said Dr. Deborah German, Vice-President for Health Affairs and Dean, University of Central Florida College of Medicine. “Call your healthcare provider dont just show up to the clinic. Your provider can determine if you need to be tested for COVID-19 and what treatments you need.”
COVID cases rising again: Florida COVID-19 infections rise for third week as officials mum on details of omicron
Omicron is expected to become the dominant coronavirus variant in the European Union by mid-January, European Commission President Ursula von der Leyen said Wednesday.
But how do you tell if you have it? For the average person, there may be no way to differentiate between the omicron variant and any other SARS-CoV-2 strains without tests.
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Diarrhea
These are not the only possible symptoms, and everyone will react differently.
How Serious Is The Flu
Most people get a mild case of flu that makes them sick for 1-2 weeks, then they get completely better. Flu can also cause very severe disease, especially in babies, elderly people, and people with certain health conditions. During the 2019-20 flu season the CDC estimated that flu caused 38 million illnesses, 400,000 hospitalizations, and 22,000 deaths in the United States.
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Wintery Mix Of Viruses
Winter is the prime cold and flu season. Youre more likely to be indoors and closer to others when its colder outside. Weather also plays a role in the spread of viruses.
Cold and flu viruses survive better and are more transmissible if its cooler and if theres lower humidity, Gordon explains.
Experts are concerned that flu and COVID-19 cases may increase and overlap in the winter. Flu cases usually start to increase around October and peak between December and February. Being infected with flu and SARS-CoV-2 at the same time is possible, as is showing symptoms of both.
If youre sick with the flu, your doctor may prescribe antiviral drugs. Such drugs can make your flu milder and shorten the time you are sick. They work best if theyre used early in your illness.
The FDA has also approved one antiviral drug, called remdesivir, to treat COVID-19. Other treatments are in development and under review. No complementary approaches have been shown to be helpful for fighting off flu or COVID-19.
Fortunately, strategies to prevent the spread of COVID-19 also prevent the spread of flu and cold. Measures like masking and social distancing work for other respiratory viruses, as well as COVID-19, says Dr. Chip Walter, who studies vaccine development at Duke University.
Transmission Of Common Human Coronaviruses
Common human coronaviruses usually spread from an infected person to others through
- the air by coughing and sneezing
- close personal contact, like touching or shaking hands
- touching an object or surface with the virus on it, then touching your mouth, nose, or eyes before washing your hands
In the United States, people usually get infected with common human coronaviruses in the fall and winter, but you can get infected at any time of the year. Young children are most likely to get infected, but people can have multiple infections in their lifetime.
Protect yourself from getting sick
- wash your hands often with soap and water for at least 20 seconds
- avoid touching your eyes, nose, or mouth with unwashed hands
- avoid close contact with people who are sick
Protect others when you are sick
- stay home while you are sick
- avoid close contact with others
- cover your mouth and nose when coughing or sneezing
- clean and disinfect objects and surfaces
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What Is A Flu Pandemic
Flu pandemics happen when a new strain of the flu A virus appears. A new viral strain quickly spreads because most people aren’t immune and a vaccine that offers immediate protection isn’t widely available. As a result, it spreads across several countries around the world, causing widespread illness.
The World Health Organization says the following conditions can lead to a flu pandemic:
- The virus is able to infect humans
- The virus is able to spread easily from human to human
- The virus must cause serious illness or death in humans
While flu pandemics are rare, they do occur periodically. There have been four flu pandemics since the beginning of the 20th century, the most severe being the Spanish flu of 1918:
- 1918 Spanish flu pandemic: Killed approximately 675,000 in the U.S.
- 1957-1958 Asian flu pandemic: Caused an estimated 116,000 U.S. deaths
- 1968 Hong Kong flu pandemic: Linked to around 100,000 deaths in the U.S.
- 2009 H1N1 flu pandemic: Responsible for an estimated 12,469 U.S. deaths
Just like with an epidemic, a flu pandemic is over when the number of cases is no longer above a defined threshold. However, the virus can continue to circulate in humans even after the pandemic is over. Take the 2009 H1N1 flu pandemic: Even though WHO declared an end to this pandemic in 2010, H1N1 continues to circulate as a seasonal flu virus, causing illness and hospitalization worldwide every year.
Duration Of Cold And Flu
The duration of a cold or the flu varies depending on the virus involved and your immune systems ability to fight off infection. Thats why the very young, the elderly, and people with chronic illnesses are most susceptible to viral infections and possible complications.
The best weapon we have is our own immune system, says Donald W. Novey, MD, a family and integrative medicine specialist in Poulsbo, Washington. Good nutrition, adequate sleep and exercise, and low levels of stress can bolster the immune system. A failure on any one of these four points can weaken the immune system and either prolong an existing cold or lead to more frequent ones, Dr. Novey says.
Cold symptoms typically subside within 7 to 10 days, while the flu typically lasts three to seven days with severe symptoms subsiding after a few days. But some symptoms, like fatigue and cough, can linger for weeks.
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