Bacterial Diseases: What are they? Symptoms, Causes, Risk Factors, Treatment and Complications

Bacteria are living beings that have a single cell and under a microscope they look like balls and rods. They are so small that a line of 1000 could fit in a pencil eraser.

Most bacteria will not hurt you, less than 1% of different types make people sick.

Many are useful, some bacteria help to digest food, destroy cells that cause disease and give the body the necessary vitamins, bacteria are also used in the manufacture of healthy foods such as yogurt and cheese.

But infectious bacteria can make you sick. They reproduce quickly in your body. Many emit chemicals called toxins, which can damage tissue and make it sick.

Examples of bacteria that cause infections include:

  • Streptococcus.
  • Staphylococcus.
  • Coli.

Antibiotics are the usual treatment, when you take antibiotics, follow the instructions carefully.

Every time you take antibiotics, you increase the chances that the bacteria in your body will learn to resist them and cause resistance to antibiotics. Later, you could get or spread an infection that these antibiotics can not cure.

What are Bacterial Diseases?

Bacterial diseases include any type of disease caused by bacteria. Bacteria are a type of microorganism, which are small life forms that can only be seen with a microscope. Other types of microorganisms include viruses, some fungi and some parasites.

Millions of bacteria normally live in the skin, in the intestines and in the genitals. The vast majority of bacteria do not cause disease, and many bacteria are really useful 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 diseases are called pathogenic bacteria. Bacterial diseases occur when pathogenic bacteria enter the body and begin to reproduce and displace healthy bacteria, or grow in tissues that are normally sterile.

Harmful bacteria can also emit toxins that harm the body. Common pathogenic bacteria and the types of bacterial diseases they cause include:

  • Escherichia coli and Salmonella cause food poisoning.
  • Helicobacter pylori causes gastritis and ulcers.
  • Neisseria gonorrhoeae causes sexually transmitted disease gonorrhea.
  • Neisseria meningitidis causa meningitis.
  • Staphylococcus aureus causes a variety of infections in the body, including boils, cellulitis, abscesses, wound infections, toxic shock syndrome, pneumonia and food poisoning.
  • Streptococcal bacteria cause a variety of infections in the body, including pneumonia, meningitis, ear infections and streptococcal pharyngitis .

Bacterial diseases are contagious and can cause many serious or life-threatening complications, such as blood poisoning (bacteremia), kidney failure and toxic shock syndrome.

What are the Symptoms of Bacterial Disease?

The symptoms of bacterial diseases vary according to the type of bacterial infection, the area of ​​the body that is infected and other factors, such as the patient’s age and health history.

The symptoms of bacterial diseases can also resemble the symptoms of other diseases, such as colitis, influenza, and viral infections. The classic symptom of a bacterial infection is fever, although not all people with a bacterial infection will have a fever.

Symptoms of the bacterial disease may include:

  • Urine blood and pain when urinating frequently.
  • Diarrhea.
  • Flu-like symptoms (fatigue, fever, sore throat, headache, cough, pain and discomfort).
  • Irritability.
  • Nausea and vomiting.
  • Pain such as pain in the joints, ears or abdomen.
  • Eruptions, injuries and abscesses.
  • Neck stiffness.
  • Weakness.

In babies, the signs of a bacterial disease may also include:

  • Bulge of the soft spot on the top of the head.
  • Difficulty with feeding
  • Excessive crying or irritability.
  • Excessive sleepiness
  • Serious symptoms that may indicate a life-threatening condition

In some cases, bacterial diseases can cause serious or life-threatening complications, such as sepsis or kidney failure.

Seek immediate medical attention if you or someone you are with has any of the following symptoms:

  • Confusion or delirium.
  • Deep and humid thoracic cough that produces yellowish, green or brownish phlegm.
  • Difficulty breathing, wheezing or shortness of breath.
  • High fever (more than 101 degrees).
  • Inappropriate change in alertness or level of awareness.

Babies : sunken fontanel (soft spot) on the top of the head, lethargy, no tears with crying and few or no wet diapers.

  • Lethargy or lack of response.
  • Do not urinate or urinate small amounts of tea-colored urine.

What Causes Bacterial Diseases?

Bacterial diseases are caused by harmful bacteria (pathogenic bacteria). The vast majority of bacteria do not cause disease, and many bacteria are really useful and even necessary for good health.

Bacterial diseases occur when pathogenic bacteria enter an area of ​​the body that is normally sterile, such as the bladder, or when they move useful bacteria in places such as the intestines, vagina or mouth.

Less common, bacterial infections can occur when healthy bacteria multiply uncontrollably. Several ways in which pathogenic bacteria can enter the body.

Pathogenic bacteria can enter the body through a variety of means including:

  • Pollution of bites, cuts, rashes, abrasions and other cuts in the skin, gums and tissues.
  • Eating contaminated food.
  • Being bitten by an infected insect.
  • Have sexual contact with an infected person.
  • Inhalation of contaminated droplets transported by air to the nose and lungs.
  • Kissing an infected person.
  • Share needles to tattoo or use drugs.
  • Through the eyes, the ears or the urethra.
  • Touch infected feces or body fluids and do not wash your hands before eating or touching your mouth, eyes or nose.

Once the bacteria enter the body, a healthy immune system will recognize the bacteria as foreign invaders and will try to kill or prevent the bacteria from reproducing.

However, even in a healthy person, the body is not always able to prevent the bacteria from multiplying and spreading. As harmful bacteria reproduce, they can expel healthy bacteria and microorganisms and emit toxins that damage body cells.

What are the risk factors for bacterial diseases?

Bacterial diseases can occur in any age group or population, but a number of factors increase the risk of developing bacterial diseases. Not all people with risk factors will get bacterial diseases.

Risk factors for bacterial diseases include:

  • Being a baby, child or older adult.
  • Eat raw or undercooked eggs or meats.
  • Consume expired food or eat leftovers that have been stored for more than two or three days.
  • Have a genetic predisposition to bacterial infection.
  • Having a compromised immune system due to an immunodeficiency disorder, HIV / AIDS, diabetes, cancer or cancer treatment, kidney disease or taking steroid medications.
  • Have a chronic illness
  • Malnutrition.
  • Do not wash your hands often, especially after using the bathroom, touching pet feces, touching reptiles or touching raw food or food contaminated with bacteria.
  • Significant exposure to a person with a bacterial disease.

Reducing your Risk of Bacterial Diseases

You can reduce your risk of developing or transmitting bacterial diseases by:

  • Avoid contact with a person who has a bacterial disease or its symptoms, such as fever, vomiting or diarrhea.
  • Cover your mouth and nose with a tissue when sneezing or coughing, then wash your hands.
  • Thaw food in the refrigerator or in the microwave, not on the counter.
  • Refrigerate the leftovers immediately and take them within two or three days, unless they have been frozen.
  • Consume a healthy diet high in whole grains, fruits and vegetables, and contain low-fat proteins and low-fat dairy products or other sources of calcium.
  • Rest enough and minimize stress.
  • Obtain the recommended vaccines for bacterial diseases, such as meningitis, pneumonia, tetanus and rabies.
  • Seek regular medical attention and follow your treatment plan for a chronic illness.
  • Throw out expired foods or perishable foods that have been at room temperature for two hours or more.
  • Use antibacterial products to clean surfaces, such as keyboards, telephones and sinks.
  • Wash hands after using the bathroom and after contact with feces of pets, reptiles, dirty diapers, raw foods and sick people.
  • Washing dishes, utensils and cutting boards that have been exposed to raw meats or poultry in hot, soapy water.
  • Wear long pants and sleeves, and use insect repellent when in tall grass or in wooded areas.

How are Bacterial Diseases Treated?

Bacterial diseases are treated with antibiotics . Antibiotics work by eliminating harmful bacteria or preventing them from reproducing and spreading. Different types of antibiotics are effective in treating specific types of bacteria.

Antibiotics can be administered orally, intravenously or by intramuscular injection, depending on the type and severity of the bacterial disease and other factors. General types of antibiotics include:

The treatment of bacterial infections also includes:

  • Good nutrition.
  • Hospitalization and intensive care in some cases, especially if complications occur.
  • Increase in fluids
  • Break.

People who have had close contact with a person with a serious bacterial disease, such as bacterial meningitis, may also need treatment and control of the disease, even in the absence of symptoms.

Sometimes an antibiotic that used to work in the treatment of a bacterial disease is no longer effective. This is called antibiotic resistance. This makes a bacterial disease more difficult to treat and can lead to serious complications such as sepsis, coma and death.

What are the Possible Complications of Bacterial Diseases?

In some people, bacterial diseases can lead to serious complications, even at risk to life. Therefore, it is important that you visit your healthcare provider when you experience symptoms of a bacterial infection.

Following the treatment plan described by your doctor can help reduce any possible complications, including:

  • Coma.
  • Renal insufficiency.
  • Septicemia, which is a potentially deadly blood infection that can lead to a response throughout the body called sepsis.
  • Severe dehydration and electrolyte imbalance.
  • Septic shock .
  • Toxic shock syndrome.

Bacteria are fascinating organisms, they are around us and many bacteria help us, bacteria help in the digestion of food, the absorption of nutrients, the production of vitamins and protection against other harmful microbes.

Conversely, a number of diseases that affect humans are caused by disease-causing bacteria called pathogenic bacteria, and they do so by producing poisonous substances called endotoxins and exotoxins .

These substances are responsible for the symptoms that occur with diseases related to bacteria. Symptoms can vary from mild to severe, and some can be fatal.

Necrotizing fasciitis (carnivorous disease)

Necrotizing fasciitis is a serious infection most commonly caused by Streptococcus pyogene s bacteria . S. pyogenes is a cocci bacteria that typically colonizes the skin and throat areas of the body.

S. pyogenes are bacteria that eat meat, producing toxins that destroy body cells, specifically red blood cells and white blood cells. This results in the death of infected tissue or necrotizing fasciitis.

Other types of bacteria that can also cause necrotizing fasciitis include Escherichia coli, Staphylococcus aureus, Klebsiella and Clostridium.

People develop this type of infection most commonly by the entry of bacteria into the body through a cut or other open wound in the skin. Necrotizing fasciitis is not usually transmitted from person to person and the occurrences are random. Healthy people with an immune system that functions properly and who practice good hygiene of wound care have a low risk of developing the disease.

Staphylococcal infections

Methicillin- resistant Staphylococcus aureus (MRSA) are bacteria that can cause serious health problems. MRSA is a strain of Staphylococcus aureus or Staph bacteria , which has developed resistance to penicillin and antibiotics related to penicillin, including methicillin.

MRSA is usually transmitted through physical contact and must pass through the skin, through a cut, for example, to cause an infection. MRSA is most commonly acquired as a result of hospital stays. These bacteria can adhere to several types of instruments, including medical equipment.

If MRSA bacteria gain access to the body’s internal systems and cause a staph infection, the consequences could be fatal. These bacteria can infect bones, joints, heart valves and lungs.


Bacterial meningitis is an inflammation of the protective covering of the brain and spinal cord, known as meninges. This is a serious infection that can cause brain damage and even death.

A severe headache is the most common symptom of meningitis. Other symptoms include stiff neck and high fever. Meningitis is treated with antibiotics. It is very important that antibiotics begin as soon as possible after infection to help reduce the risk of death.

A meningococcal vaccine can help prevent it for those who are at higher risk of developing this disease.

Bacteria, viruses, fungi and parasites can cause meningitis. Bacterial meningitis can be caused by several bacteria. The specific bacteria that cause bacterial meningitis vary according to the age of the infected person.

For adults and adolescents, Neisseria meningitidis and Streptococcus pneumoniae are the most common causes of the disease. In newborns, the most common causes of bacterial meningitis are Group B Streptococcus, Escherichia coli, and Listeria monocytogenes.


Pneumonia is an infection of the lungs. Symptoms include high fever, cough and shortness of breath. While several bacteria can cause pneumonia, the most common cause is Streptococcus pneumoniae. S. pneumoniae typically resides in the respiratory tract and usually does not cause infection in healthy individuals.

In some cases, the bacteria become pathogenic and cause pneumonia. The infection usually begins after the bacteria are inhaled and reproduce rapidly in the lungs.

S. pneumoniae can also cause ear infections, sinusitis and meningitis. If necessary, most pneumonias have a high chance of cure with antibiotic treatment. A pneumococcal vaccine can help prevent those at higher risk from developing this disease.

Streptococcus pneumoniae is a bacterium in the form of cocci.


Tuberculosis (TB) is an infectious disease of the lungs. It is usually caused by a bacterium called Mycobacterium tuberculosis. Tuberculosis can be fatal without proper treatment.

The disease is spread through the air when an infected person coughs, sneezes or even speaks. In several developed countries, TB has increased with the increase in HIV infections due to the weakening of the immune system of people infected with HIV.

Antibiotics are used to treat tuberculosis. Isolation to help prevent the spread of an active infection is also typical of the treatment of this disease. The treatment can be long, lasting from 6 months to a year, depending on the severity of the infection.


Cholera is an intestinal infection caused by the bacterium Vibrio cholerae . Cholera is a foodborne disease that is usually transmitted by food and water contaminated with Vibrio cholerae .

Around the world, approximately 3 to 5 million cases occur annually, with approximately 100,000 more deaths. Most cases of infection occur in areas with little water and food sanitation.

Cholera can vary from mild to severe. Symptoms of the severe form include diarrhea, vomiting and cramps. Cholera is usually treated by hydrating the infected person. In more severe cases, antibiotics can be used to help the person recover.


The dysentery bacillus is an intestinal inflammation caused by bacteria in the genus Shigella . Like cholera, it is transmitted through contaminated food and water. Dysentery is also transmitted by people who do not wash their hands after going to the bathroom.

The symptoms of dysentery can vary from mild to severe. Serious symptoms include bloody diarrhea, high fever and pain. Like cholera, dysentery is usually treated by hydration.

It can also be treated with antibiotics depending on the severity. The best way to prevent the spread of Shigella is to wash and dry your hands properly before handling food and avoid drinking local water in areas where there is a high risk of getting dysentery.