Influenza and Colds

Influenza, commonly known as the flu, is an infectious disease caused by RNA viruses of the family Orthomyxoviridae (the influenza viruses).

The Common Cold - There are over one billion colds and cases of the flu in the United States every year. The common cold is an illness caused by a virus infection located in the nose and leads to symptoms such as runny nose, sneezing, sore throat, cough, headache, fever, etc. which are a result of the body's response to the infection. There are currently no known ways to cure a cold, we can only fight the symptoms using medicines such as antihistamines, decongestants, and cough suppressants. The best way to avoid getting a cold is to focus on cold prevention by wash your hands frequently, avoiding touching your mouth and nose, and maintaining distance from people how are infected with the virus.

Influenza - A contagious respiratory illness caused by the influenza viruses. It can cause mild to severe illness, and at times can even lead to death. Influenza should not be confused with other illnesses such as avian flu, swine flu, canine flu, or pandemic flu. The flu shot is similar to an immunization in that it injects you with a small amount of inactive influenza virus which is supposed to make your body more resistant to being exposed to that virus throughout the winter. The flu shot is one of the best ways to prevent flu contamination. Once infected with the flu virus, flu symptoms can also be treated using medicines such as antihistamines, decongestants, and cough suppressants.

Influenza is a viral infection that affects mainly the nose, throat, bronchi and, occasionally, lungs. Infection usually lasts for about a week, and is characterized by sudden onset of high fever, aching muscles, headache and severe malaise, non-productive cough, sore throat and rhinitis.

The viruses pass through the air and enter your body through your nose or mouth. Between 5% and 20% of people in the U.S. get the flu each year. The flu can be serious or even deadly for elderly people, newborn babies and people with certain chronic illnesses.

Influenza is transmitted from infected humans through the air by coughs or sneezes, creating aerosols containing the virus, and from infected birds through their droppings. Influenza can also be transmitted by saliva, nasal secretions, feces and blood. Infections also occur through contact with these body fluids or with contaminated surfaces. Flu viruses can remain infectious for about one week at human body temperature, over 30 days at 0 °C (32 °F), and for much longer periods at very low temperatures.

Influenza infection often causes a more severe illness with a mortality rate (death rate) of about 0.1% of people who are infected with the virus. Unusually severe worldwide outbreaks (pandemics) have occurred several times in the last 100 years since influenza virus was identified in 1933.

Influenza viruses are divided into three types, designated A, B, and C.

Influenza types A and B are responsible for epidemics of respiratory illness that occur almost every winter and are often associated with increased rates of hospitalization and death.

Influenza type C differs from types A and B in some important ways. Type C infection usually causes either a very mild respiratory illness or no symptoms at all; it does not cause epidemics and does not have the severe public health impact of influenza types A and B.

Efforts to control the impact of influenza are aimed at types A and B.

In humans, common symptoms of the disease are chills and fever, pharyngitis, muscle pains, severe headache, coughing, weakness and general discomfort.[

Symptoms of influenza can start quite suddenly one to two days after infection.

Usually the first symptoms are chills or a chilly sensation, but fever is also common early in the infection, with body temperatures as high as 39 °C (approximately 103 °F). Many people are so ill that they are confined to bed for several days, with aches and pains throughout their bodies, which are worse in their backs and legs.

Symptoms of influenza may include:

Abdominal pain (in children with influenza B)

Body aches, especially joints and throat Coughing and sneezing Headache Irritated watering eyes Nasal congestion Extreme coldness and fever Fatigue Reddened eyes, skin, mouth, throat and nose

Vaccination against influenza with an influenza vaccine is often recommended for high-risk groups, such as children and the elderly. CDC recommends a yearly flu vaccine as the first and most important step in protecting against this serious disease.

Vaccinations against influenza are usually given to people in developed countries with a minor risk of contracting the disease.

The most common human vaccine is the trivalent influenza vaccine that contains purified and inactivated material from three viral strains. Typically, this vaccine includes material from two influenza A virus subtypes and one influenza B virus strain. A vaccine formulated for one year may be ineffective in the following year, since the influenza virus changes rapidly over time, and different strains become dominant. Antiviral drugs can be used to treat influenza, with neuraminidase inhibitors being particularly effective.

Further Information Regarding Influenza and Colds

H1N1 and Seasonal Flu Arthritis or Rheumatic Disease Information
People with certain types of arthritis, called inflammatory or systemic arthritis or autoimmune rheumatic disease, have a higher risk of getting flu-related complications, such as pneumonia. Inflammatory arthritis affects the immune system which controls how well your body fights off infections.

Influenza Vaccine Allergy Clinic
Mayo Clinic will offer an influenza vaccine allergy clinic beginning Monday, Oct. 5th 2009.

Women Who are Pregnant Should Get Flu Shots
Pregnant women should be sure to get all their flu shots as soon as the vaccines become available this year to protect them against both the seasonal flu and the H1N1 (swine) flu, according to eight leading national maternal and infant health organizations.

When Should I Receive a Flu Shot - Influenza Vaccine
In the Northern Hemisphere the flu (Medically referred to as influenza) season generally runs from November to April, with most cases occurring between late December and early March, but the flu, or anti-flu, vaccine is usually offered between September and mid-November. Although you can get a flu shot well into flu season, it's best to try to get it earlier rather than later.

1 in 6 Public Health Workers Unlikely to Respond in Pandemic Flu Emergency
Approximately 1 in 6 public health workers said they would not report to work during a pandemic flu emergency regardless of its severity, according to a survey led by researchers at the Johns Hopkins Bloomberg School of Public Health.

Influenza Monitoring by the US Military
According to the Institute of Medicine the DoD Global Emerging Infections System, through its avian influenza/pandemic influenza activities at the DoD overseas laboratories and headquarters, has contributed greatly to the development of laboratory and communications infrastructures within partner countries.

Cold and Flu Remedies or Get a Flu Shot?
Many people are interested in natural and herbal cold and flu remedies. The reasons vary. Some people are aware that an individual may experience an adverse reaction to flu shots. Other people just prefer to use herbs and botanicals as opposed to chemicals and drugs.

Types of Flu Shot Reactions
The common flu shot reactions include swelling, soreness and redness at the point of injection, body aches and low grade fever. Some people are concerned about more serious flu shot adverse reactions. The Center for Disease Control and Prevention (CDC) says that more serious flu shot reactions are rare and that the benefits of vaccination outweigh the risks.

Engineering Flu Vaccines
A new computerized method of testing could help world health officials better identify flu vaccines that are effective against multiple strains of the disease. Rice University scientists who created the method say tests of data from bird flu and seasonal flu outbreaks suggest their method can better gauge the efficacy of proposed vaccines than can tests used today.

Drug Resistant Influenza A Virus High Risk to Patients
A mutation of the influenza A(H1N1) virus that is resistant to the drug oseltamivir may pose a serious health threat to hospitalized patients who have a weakened immune system, according to a study to be published in the March 11 issue of JAMA, and being released early online because of its public health importance.