Diseases, Conditions, Syndromes

Eating elderberries can help minimize influenza symptoms

Folk medicines and herbal products have been used for millennia to combat a whole range of ailments, at times to the chagrin of modern scientists who have struggled to explain their medicinal benefits.

Diseases, Conditions, Syndromes

How the flu vaccine fails

Influenza is ubiquitous. Every fall, we line up to get our flu shots with the hope that we will be protected from the virus that infects 10 to 20 percent of people worldwide each year. But some years, the vaccine is less ...

Diseases, Conditions, Syndromes

Common food additive may weaken defenses against influenza

Research conducted in mice suggests the food additive tert-butylhydroquinone (tBHQ)—found in many common products from frozen meat to crackers and fried foods—suppresses the immune response the body mounts when fighting ...

Diseases, Conditions, Syndromes

When's the best time to get your flu shot?

When most of us get the flu, we spend three or four days on the couch feeling miserable, then we bounce back pretty quickly. But others have more severe symptoms and need to be hospitalised because they're at risk of life-threatening ...

Diseases, Conditions, Syndromes

October may be best time for older adults to receive flu shot

(HealthDay)—It may be best for older adults to wait until October to receive their flu vaccine, unless that delay would cause them to skip getting their flu shot altogether, according to a study published in the April issue ...

Medical research

New approach to tackle Ebola and other deadly infections

Medical Research Council scientists have isolated therapeutic antibodies from healthy volunteers exposed to the Ebola vaccine but not Ebola virus itself, suggesting that protective therapies could be developed from people ...

Immunology

A bad bout of flu triggers 'taste bud cells' to grow in the lungs

Most people who weather an infection with influenza fully recover after a week or two. But for some, a severe case of the flu can actually reshape the architecture of their lungs and forever compromise their respiratory function.

Diseases, Conditions, Syndromes

'Hibernating' research studies on standby to tackle next flu pandemic

The University of Liverpool is improving the UK's preparedness for another influenza pandemic through its involvement in an innovative network of research studies 'hibernating' on standby ready to be activated if an outbreak ...

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Influenza, commonly referred to as the flu, is an infectious disease caused by RNA viruses of the family Orthomyxoviridae (the influenza viruses), that affects birds and mammals. The most common symptoms of the disease are chills, fever, sore throat, muscle pains, severe headache, coughing, weakness/fatigue and general discomfort. Although it is often confused with other influenza-like illnesses, especially the common cold, influenza is a more severe disease than the common cold and is caused by a different type of virus. Influenza may produce nausea and vomiting, particularly in children, but these symptoms are more common in the unrelated gastroenteritis, which is sometimes, inaccurately, referred to as "stomach flu." Flu can occasionally cause either direct viral pneumonia or secondary bacterial pneumonia.

Typically, influenza is transmitted through the air by coughs or sneezes, creating aerosols containing the virus. Influenza can also be transmitted by direct contact with bird droppings or nasal secretions, or through contact with contaminated surfaces. Airborne aerosols have been thought to cause most infections, although which means of transmission is most important is not absolutely clear. Influenza viruses can be inactivated by sunlight, disinfectants and detergents. As the virus can be inactivated by soap, frequent hand washing reduces the risk of infection.

Influenza spreads around the world in seasonal epidemics, resulting in the deaths of between &10000000000250000000000250,000 and &10000000000500000000000500,000 people every year, up to millions in some pandemic years. On average 41,400 people died each year in the United States between 1979 and 2001 from influenza. In 2010 the Centers for Disease Control and Prevention (CDC) in the United States changed the way it reports the 30 year estimates for deaths. Now they are reported as a range from a low of about 3,300 deaths to a high of 49,000 per year.

Three influenza pandemics occurred in the 20th century and killed tens of millions of people, with each of these pandemics being caused by the appearance of a new strain of the virus in humans. Often, these new strains appear when an existing flu virus spreads to humans from other animal species, or when an existing human strain picks up new genes from a virus that usually infects birds or pigs. An avian strain named H5N1 raised the concern of a new influenza pandemic, after it emerged in Asia in the 1990s, but it has not evolved to a form that spreads easily between people. In April 2009 a novel flu strain evolved that combined genes from human, pig, and bird flu, initially dubbed "swine flu" and also known as influenza A/H1N1, emerged in Mexico, the United States, and several other nations. The World Health Organization officially declared the outbreak to be a pandemic on June 11, 2009 (see 2009 flu pandemic). The WHO's declaration of a pandemic level 6 was an indication of spread, not severity, the strain actually having a lower mortality rate than common flu outbreaks.

Vaccinations against influenza are usually made available to people in developed countries. Farmed poultry is often vaccinated to avoid decimation of the flocks. The most common human vaccine is the trivalent influenza vaccine (TIV) that contains purified and inactivated antigens against three viral strains. Typically, this vaccine includes material from two influenza A virus subtypes and one influenza B virus strain. The TIV carries no risk of transmitting the disease, and it has very low reactivity. A vaccine formulated for one year may be ineffective in the following year, since the influenza virus evolves rapidly, and new strains quickly replace the older ones. Antiviral drugs such as the neuraminidase inhibitor oseltamivir can be used to treat influenza, however the effectiveness is difficult to determine due to much of the data remaining unpublished.

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