Sunday, December 2, 2007

health : what is Influenza?

Influenza, most commonly known as the flu, is a highly contagious respiratory illness caused by a virus.

In most cases, people with the flu experience headaches, muscle aches, fever, weakness, and cough, but sometimes can have no symptoms at all.

Influenza can cause significant disease and death due to serious complications which can occur in the very young, the elderly and those suffering from underlying disease.

More serious infection can cause various respiratory syndromes, disorders affecting the lung, heart, brain, liver, kidneys, and muscles, and can also cause severe primary viral and secondary bacterial pneumonia.

Influenza can occur as isolated cases, in epidemics, or in pandemics.

While we often call the common cold the "flu", the common cold is rarely due to the Influenza virus. True influenza causes a much more severe illness than the usual cold.........more about flue

health : what is Sex disease ?

The sex disease syphilis adapted from a severe, debilitating illness to a milder form in order to survive, research suggests. Dr Robert Knell, of Queen Mary's College, London, argues the disease was too virulent for its own good. Sufferers became so repellent that they were unlikely to have sex. To ensure that they did, and continued to pass on the bacterium, it had to change.

Dr Knell's theory is published in the journal Biology Letters. Syphilis in its early form caused disfiguring pustules on the face accompanied by a foul smell. Dr Knell argues this would have been obvious to any potential sexual partners of a sufferers, enabling people to avoid the infected person and thereby reducing transmission.

Other symptoms, such as agonising pains in the joints, would have effectively disabled the sufferer, or at least distracted them from seeking out new sexual partners. As a result, less virulent strains of the disease were transmitted more often, thus leading to changes in the severity of the disease.

Animal examples

Changes in virulence in diseases introduced to animal populations have been observed before - but this is believed to be the first credible example of such rapid changes occurring in a human disease. Dr Knell said: 'Syphilis changed from a virulent disease to a relatively mild one in a very short period.

'Our use of antibiotics to treat it means that it may still be evolving towards lower virulence. 'Syphilis is rare nowadays but its incidence is rapidly increasing, and in recent outbreaks in the UK some of those infected noticed no symptoms at all.

'This could have serious implications concerning the spread of infectious diseases such as HIV because the chance of contracting HIV through heterosexual sex with someone who is HIV positive is about thirty times greater if you have syphilis.'

Great Pox

Syphilis first appeared in Europe in 1496 and was known as the 'Great Pox' or 'French Disease'. At first it caused terrible sickness, including severe ulceration of the part of the body first infected (often the genitals), pustules, soft tissue being eaten away to the bone, and the rapid onset of 'gummy' tumours.

However, within 50 years syphilis changed from an acute, severe and debilitating disease to the milder infection that is modern syphilis. Dr Knell says the decline in the virulence of syphilis was noted as early as five to seven years from the start of the epidemic - less than a single generation and too short a time for any resistance to the disease to be formed.This would indicate that, rather than there being any changes in people's immune systems, it was in fact the disease that evolved during this period........more about sex disease

health : what is HIV / AIDS ?

Acquired immune deficiency syndrome or acquired immunodeficiency syndrome (AIDS or Aids) is a collection of symptoms and infections resulting from the specific damage to the immune system caused by the human immunodeficiency virus (HIV) in humans,[1] and similar viruses in other species (SIV, FIV, etc.). The late stage of the condition leaves individuals susceptible to opportunistic infections and tumors. Although treatments for AIDS and HIV exist to decelerate the virus' progression, there is currently no known cure. HIV, et al., are transmitted through direct contact of a mucous membrane or the bloodstream with a bodily fluid containing HIV, such as blood, semen, vaginal fluid, preseminal fluid, and breast milk.[2][3] This transmission can come in the form of anal, vaginal or oral sex, blood transfusion, contaminated hypodermic needles, exchange between mother and baby during pregnancy, childbirth, or breastfeeding, or other exposure to one of the above bodily fluids.

Most researchers believe that HIV originated in sub-Saharan Africa during the twentieth century;[4] it is now a pandemic, with an estimated 33.2 million people now living with the disease worldwide.[5] As of January 2006, the Joint United Nations Programme on HIV/AIDS (UNAIDS) and the World Health Organization (WHO) estimate that AIDS has killed more than 25 million people since it was first recognized on June 5, 1981, making it one of the most destructive epidemics in recorded history. In 2005 alone, AIDS claimed an estimated 2.4–3.3 million lives, of which more than 570,000 were children.[6] A third of these deaths are occurring in sub-Saharan Africa, retarding economic growth and destroying human capital. Antiretroviral treatment reduces both the mortality and the morbidity of HIV infection, but routine access to antiretroviral medication is not available in all countries.[7] HIV/AIDS stigma is more severe than that associated with other life-threatening conditions and extends beyond the disease itself to providers and even volunteers involved with the care of people living with HIV..............more about HIV & AIDS

health : what is cancer ?

Cancer occurs when cells in a part of the body begin to grow out of control. Normal cells divide and grow in an orderly fashion, but cancer cells do not. They continue to grow and crowd out normal cells. Although there are many kinds of cancer, they all have in common this out-of-control growth of cells.

Different kinds of cancer can behave very differently. For example, lung cancer and breast cancer are very different diseases. They grow at different rates and respond to different treatments. That’s why people with cancer need treatment that is aimed at their kind of cancer.

Sometimes cancer cells break away from a tumor and spread to other parts of the body through the blood or lymph system. They can settle in new places and form new tumors. When this happens, it is called metastasis (meh-tas-tuh-sis). Cancer that has spread in this way is called metastatic cancer.

Even when cancer has spread to a new place in the body, it is still named after the part of the body where it started. For example, if prostate cancer spreads to the bones, it is still called prostate cancer. If breast cancer spreads to the lungs, it is still breast cancer. When cancer comes back in a person who appeared to be free of the disease after treatment, it is called a recurrence.............more about cancer