Tuberculosis

Culled from www.who.int/mediacentre/factsheets

Tuberculosis (TB) is caused by bacteria (Mycobacterium tuberculosis) that most often affect the lungs. Tuberculosis is curable and preventable.

TB is spread from person to person through the air. When people with lung TB cough, sneeze or spit, they propel the TB germs into the air. A person needs to inhale only a few of these germs to become infected.

About one-third of the world's population has latent TB, which means people have been infected by TB bacteria but are not (yet) ill with disease and cannot transmit the disease.

People infected with TB bacteria have a lifetime risk of falling ill with TB of 10%. However persons with compromised immune systems, such as people living with HIV, malnutrition or diabetes, or people who use tobacco, have a much higher risk of falling ill.

When a person develops active TB (disease), the symptoms (cough, fever, night sweats, weight loss etc.) may be mild for many months. This can lead to delays in seeking care, and results in transmission of the bacteria to others. People ill with TB can infect up to 10-15 other people through close contact over the course of a year. Without proper treatment up to two thirds of people ill with TB will die.

Key facts

• Tuberculosis (TB) is second only to HIV/AIDS as the greatest killer worldwide due to a single infectious agent.
• In 2012, 8.6 million people fell ill with TB and 1.3 million died from TB.
• Over 95% of TB deaths occur in low- and middle-income countries, and it is among the top three causes of death for women aged 15 to 44.
• In 2012, an estimated 530 000 children became ill with TB and 74 000 HIV-negative children died of TB.
• TB is a leading killer of people living with HIV causing one quarter of all deaths.
• Multi-drug resistant TB (MDR-TB) is present in virtually all countries surveyed.
• The estimated number of people falling ill with tuberculosis each year is declining, although very slowly, which means that the world is on track to achieve the Millennium Development Goal to reverse the spread of TB by 2015.
• The TB death rate dropped 45% between 1990 and 2012.
• An estimated 22 million lives saved through use of DOTS and the Stop TB Strategy recommended by WHO.

 

What Is Cancer Screening?

Culled from www.cancer.gov (National Institute of Cancer)

Cancer screening is looking for cancer before a person has any symptoms.

Screening tests can help find cancer at an early stage, before symptoms appear. When abnormal tissue or cancer is found early, it may be easier to treat or cure. By the time symptoms appear, the cancer may have grown and spread. This can make the cancer harder to treat or cure.

It is important to remember that when your doctor suggests a screening test, it does not always mean he or she thinks you have cancer. Screening tests are done when you have no cancer symptoms.

There are different kinds of screening tests.

Screening tests include the following:

• Physical exam and history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken.
• Laboratory tests: Medical procedures that test samples of tissue, blood, urine, or other substances in the body.
• Imaging procedures: Procedures that make pictures of areas inside the body.
• Genetic tests: Tests that look for certain gene mutations (changes) that are linked to some types of cancer.

Screening tests have risks.

Not all screening tests are helpful and most have risks. It is important to know the risks of the test and whether it has been proven to decrease the chance of dying from cancer.

Some screening tests can cause serious problems.

Some screening procedures can cause bleeding or other problems. For example, colon cancer screening with sigmoidoscopy or colonoscopy can cause tears in the lining of the colon.

False-positive test results are possible.

Screening test results may appear to be abnormal even though there is no cancer. A false-positive test result (one that shows there is cancer when there really isn't) can cause anxiety and is usually followed by more tests and procedures, which also have risks.

False-negative test results are possible.

Screening test results may appear to be normal even though there is cancer. A person who receives a false-negative test result (one that shows there is no cancer when there really is) may delay seeking medical care even if there are symptoms.

Finding the cancer may not improve the person's health or help the person live longer.

Some cancers never cause symptoms or become life-threatening, but if found by a screening test, the cancer may be treated. There is no way to know if treating the cancer would help the person live longer than if no treatment were given. Also, treatments for cancer have side effects.

For some cancers, finding and treating the cancer early does not improve the chance of a cure or help the person live longer.

The PDQ cancer screening summaries are written to help people learn about screening tests.

Scientists study screening tests to find those with the fewest risks and most benefits. The PDQ cancer screening summaries are based on the results of these studies and other scientific information about cancer risk and screening tests. The summaries are written to give readers the most current information about standard screening tests and tests that are being studied in clinical trials.

It can be hard to make decisions about screening tests. Before having any screening test, you may want to discuss the test with your doctor.