Bacteria vs Viruses: The differences explained

Dear Healthy Nation,

What is the difference between bacteria and viruses?

Dear reader,

Bacteria and viruses are both microscopic organisms.

Bacteria are single celled living organisms that can survive on their own and reproduce through binary fission. There are numerous bacteria in the environment and on and within our bodies, and they are useful in several industries. On the other hand, viruses are a collection of molecules and genetic material, and they need to be inside a host to survive and multiply, so they are not fully classified as living organisms.

Both bacteria and viruses can cause disease in humans, and sometimes the diseases may look similar such as respiratory tract infections or infections of the gastro-intestinal tract. This is why it is important, when unwell, to have tests done to determine the possible cause, before starting on medication, especially antibiotics. Antibiotics (anti-bacterial medication) work on bacterial infections while viral infections are usually managed through treating the symptoms. Rarely, anti-viral medication may be given for specific viral infections. Both types of infections can be prevented through maintaining good hygiene and use of the available vaccines.

Dear doctor,

Did cancer exist before man-made chemicals were around to create it? And why are cancer rates rising?

Dear reader,

Cancer refers to a group of diseases where there is abnormal cell growth that causes tissue destruction, with invasion of surrounding tissue and/or spread to other parts of the body. Cancer has affected human beings (and animals) throughout history, with the earliest written records of breast cancer being from Egypt in 1600BC. The diagnosis of cancer increased between the 15th and 17th centuries when the practice of postmortems became more acceptable in Europe.

There is an increase in cancer cases and deaths due to better diagnosis, people living longer, and the impact of lifestyle and environmental factors.

For cancer to develop, there are many stages involved; from the initial abnormal cell multiplication to establishment of a cancerous growth. There are over 100 types of cancer that affect human beings, and therefore, there is no single cause of all the cancers and no single treatment. Cancer is a genetic disease - there are genetic changes that affect how the genes control cell division and function. The genetic abnormalities may be due to the impact of other risk factors, or as a result of inherited genes, or due to spontaneous mutations or errors as the cells divide.

The risk factors associated with cancer include:

    Tobacco use

    Excessive alcohol consumption

    Obesity

    Lack of physical exercise

    Poor diet

    Environmental pollutants such as asbestos and benzene

    Exposure to ionising radiation

    Infections such as Human Papilloma Virus (HPV), Hepatitis B and C, Helicobacter pylori, among others. HIV may also increase the risk of cancers caused by some infections due to the lowered immunity.

While there is no way to alter the genes, some risk factors can be modified or avoided. For example:    Having a healthy diet rich in vegetables and fruits, and with limited processed foods and salt intake

     Maintaining healthy weight

     Regular physical exercise

    Practising safe sex

     Vaccination against HPV and Hepatitis B

     Avoiding tobacco use and excessive alcohol consumption       Avoiding indoor smoke from “dirty” fuels

     Access to early and good quality health care

 Dear doctor,

My feet swell on and off, especially when I sit for long. What could be the problem?

Mary

Dear Mary,

It is likely that you oedema, which is accumulation of fluid under the skin or between the tissues. More commonly, this happens in the feet and it can also affect the legs, thighs and hands. Oedema can also affect internal organs like the brain, heart, abdomen and lungs.

In many instances, this swelling of the feet is due to poor circulation while stationary for long, and it resolves on its own, and can be prevented by regular exercise of the feet, even in a siting position.

However, oedema may also develop due to injury, an infection, or a blood clot affecting blood flow. Other possible causes are problems with blood flow and drainage, or other diseases like kidney disease, liver disease, heart failure and thyroid disease. The swelling may also be due to inflammation due to arthritis.

It is advisable for you to be reviewed by a doctor for physical examination and relevant tests, which may include a Doppler ultrasound (a scan that checks the blood flow within the veins). Other tests may include checking the heart, kidneys, liver, thyroid, blood level and a pelvic ultrasound scan to check for swellings/tumours in the pelvis. Sometimes, especially in women between 20 and 30 years of age, there may be no identifiable underlying cause. Managing the oedema includes increased leg exercise, elevating the legs, maintaining healthy weight, reducing salt intake; reducing excessive fluid intake and avoiding prolonged sitting or standing at one place. If sitting or standing for long is necessary, leg exercises can still be done from these positions. Any underlying causes will be treated. There are medications that may be prescribed to improve blood flow. There are also compression devices/stockings that can be prescribed to improve blood and lymphatic flow.

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