Bacterial infection
Bacteria are microorganisms which are typically one-celled, have no chlorophyll,
multiply by simple division. Bacteria, also called germs, are microscopic
organisms not visible with the naked eye can be seen only by use a microscope.
Bacteria are everywhere, both inside and outside of the body. Bacteria can live in a
variety of environments.
Characteristics of the bacterium
Most bacteria move around with the aid of small lashing tails (flagella) by
whipping their bodies from side to side.
Under the right conditions, a bacterium reproduces by dividing into two.
Each ‘daughter’ cell then divides into two and so on, so that a single
bacterium can bloom into a population of some 500,000 or more within just
eight hours.
If the environmental conditions don’t suit the bacteria, some varieties morph
into a dormant state. They develop a tough outer coating and await the
appropriate change of conditions. These dormant bacteria are called spores.
Spores are harder to kill than active bacteria because of their outer coating.
Bacteria types
Bacteria that cause disease are broadly classified according to their shape.
The four main groups include:
Bacilli – shaped like a rod with a length of around 0.03mm. Illnesses
such as typhoid are caused by bacilli strains.
Cocci – shaped like a sphere with a diameter of around 0.001mm.
Depending on the arrange, cocci bacteria group themselves in a range
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of ways, such as in pairs, long lines or tight clusters. Examples
include Staphylococci and Gonococci.
Spirillus – as the name suggests, these bacteria are shaped like tiny
spirals. are responsible for a range of diseases, including the sexually
transmissible infection syphilis.
How bacteria enter the body:-
To cause disease, pathogenic bacteria must gain access into the body. The range of
access routes for bacteria includes:
1. Cuts
2. Contaminated food or water
3. Close contact with an infected person
4. Contact with the faeces of an infected person
5. Breathing in the exhaled droplets when an infected person coughs or sneezes
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6. Indirectly, by touching contaminated surfaces – such as taps, toilet handles,
toys and nappies
What are bacterial diseases?
Bacterial diseases include any type of illness caused by bacteria. Millions of
bacteria normally live on the skin, in the intestines, and on the genitalia. The
vast majority of bacteria do not cause disease, and many bacteria are actually
helpful and even necessary for good health. These bacteria are sometimes
referred to as “good bacteria” or “healthy bacteria.”
Harmful bacteria that cause bacterial infections and disease are called
pathogenic bacteria. Bacterial diseases occur when pathogenic bacteria get
into the body and begin to reproduce. Harmful bacteria may also emit toxins
that damage the body.
Some diseases caused by bacteria:-
1. Tuberculosis (TB):-
Tuberculosis (TB) is an infectious disease usually caused by the bacterium
Mycobacterium tuberculosis (MTB). Tuberculosis generally affects the
lungs, but can also affect other parts of the body.
TB bacteria can live in the body without making you sick. This is called
latent TB infection. In most people who breathe in TB bacteria and become
infected, the body is able to fight the bacteria to stop them from growing.
People with latent TB infection do not feel sick and do not have any
symptoms. People with latent TB infection are not infectious and cannot
spread TB bacteria to others. However, if TB bacteria become active in the
body and multiply, the person will go from having latent TB infection to
being sick with TB disease.
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TB bacteria become active if the immune system can't stop them from
growing. When TB bacteria are active (multiplying in your body), this is
called TB disease. People with TB disease are sick. They may also be able to
spread the bacteria to people they spend time with every day.
The symptoms of active TB of the lung are coughing, sometimes with
sputum or blood, chest pains, weakness, weight loss, fever and night sweats.
2. Typhoid Fever
Typhoid fever is caused by Salmonella typhi bacteria. Typhoid fever spreads
through contaminated food and water or through close contact with someone
who's infected. Signs and symptoms usually include high fever, headache,
abdominal pain, and either constipation or diarrhea.
Most people with typhoid fever feel better within a few days of starting
antibiotic treatment, although a small number of them may die of
complications.
After the ingestion of contaminated food or water, the Salmonella bacteria
invade the small intestine and enter the bloodstream temporarily. The
bacteria are carried by white blood cells in the liver, spleen, and bone
marrow, where they multiply and reenter the bloodstream. People develop
symptoms, including fever, at this point. Bacteria invade the gallbladder,
biliary system, and the lymphatic tissue of the bowel. Here, they multiply in
high numbers. The bacteria pass into the intestinal tract and can be identified
in stool samples.
3. Cholera:-
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Cholera is an infectious disease that causes severe watery diarrhea, which
can lead to dehydration and even death if untreated. It is caused by eating
food or drinking water contaminated with a bacterium called Vibrio cholera.
Symptoms of cholera can begin as soon as a few hours or as long as five
days after infection. Often, symptoms are mild. But sometimes they are very
serious. About one in 20 people infected have severe watery diarrhea
accompanied by vomiting, which can quickly lead to dehydration.
4. Pneumococcal Pneumonia:-
Pneumococcal pneumonia is caused by bacteria called Streptococcus
pneumoniae. can infect the upper respiratory tract and can spread to the
blood, lungs, middle ear, or nervous system.
Pneumococcus is spread through contact with people who are carry the
bacteria in their throat. You can get pneumococcal pneumonia from
respiratory droplets from the nose or mouth of an infected person. It is
common for people, especially children, to carry the bacteria in their throats
without being sick.
Pneumococcal pneumonia may begin suddenly have a severe shaking chill
which is usually followed by : High fever, Cough ,Shortness of breath,
Rapid breathing and Chest pains.
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