Bacterial Diseases in Humans

Bacterial diseases are caused by harmful bacteria which invade and multiply within the human body and cause serious health issues. These infections can affect various organs and symptoms which can vary depending upon what kind of bacteria is involved. Examples of bacterial diseases include tuberculosis, Strep throat, cholera and typhoid fever. Each of these diseases has unique characteristics and causative bacterial agents. It is an important part of the chapter Human Health and Diseases of Class 12 Biology. Therefore it becomes important from an examination point of view as it carries weightage.

Latest: NEET 2024 Paper Analysis and Answer Key 

Don't Miss: Most scoring concepts for NEET | NEET papers with solutions

New: NEET Syllabus 2025 for Physics, Chemistry, Biology

NEET Important PYQ & Solutions: Physics | Chemistry | Biology | NEET PYQ's (2015-24)

This Story also Contains

1. What are Bacterial Diseases?
2. Bacterial Diseases in Humans
3. Bacterial Disease Causes
4. Bacterial Disease Symptoms
5. Risk Factors Involved in Bacterial Diseases
6. Diagnosis of Bacterial Diseases
7. Treatment of Bacterial Diseases
8. Prevention of Bacterial Diseases
9. Tips, Tricks, and Strategies for Bacterial Diseases

What are Bacterial Diseases?

Bacterial diseases are infections caused by pathogenic bacteria. Not all bacteria are harmful. Bacterial infections are one cause of infectious diseases. Non-pathogenic (beneficial) bacteria play crucial roles in maintaining human health.

Pathogenic bacteria can cause major health problems, but non-pathogenic bacteria help with functions like immunity and digestion. Antibiotics are used as first-line treatment of serious bacterial infections. Some of the important points are discussed below:

• Pathogenic bacteria are responsible for diseases while non-pathogenic bacteria form some of the important functions inside our body.

• Identification of Bacterial disease includes which of the following bacteria has been responsible and causing the disease and treating its infections.

• Each of the bacterial diseases has its unit symptoms that have its mechanism and causative bacterial agent which is responsible for the infection.

• Bacterial diseases spread quickly and can lead to a high mortality rate if not managed properly.

• Understanding bacterial disease and their causative agent also helps in developing strategies against the prevention and treatment of the bacterial disease.

Also Read

• Health and Disease MCQ

• Human Health And Disease

• Vaccination

• Strategies For Enhancement In Food Production

What are Bacteria?

Bacteria are microorganisms with a single cell devoid of a true nucleus. They can be found in almost every habitat on Earth: soil, oceans, rocks, and even arctic snow and the human body. Bacteria reproduce using asexual methods, i.e. binary fission. They exist in different shapes: rod-shaped (bacillus), sphere-shaped (coccus), spiral-shaped (spirillum), and comma-shaped (vibrio).

Bacterial Diseases in Humans

Some bacterial diseases with their causative agents are listed below, along with their causative agents:

Bacterial Disease Causes

Bacterial diseases can spread in various ways.

Mechanisms of Bacterial Disease

• Pathogenesis Bacterial diseases are caused by pathogenic bacteria through various mechanisms.
• Bacteria can invade the body through inhalation, ingestion, wounds, etc.

• When bacteria enter the body, they colonize host cells by avoiding the immune system.

• Bacteria can damage the tissue directly or indirectly. They can damage the tissue directly. For indirect damage, they produce toxins which leads to Bacterial infections.

Toxin Production

• Exotoxins are proteins secreted by bacteria that harm particular tissues within their host. Example: Tetanus toxin.

• Endotoxins are bacterial cell wall components that are released after a cell dies and cause extensive inflammation. Gram-negative bacteria are an example of lipopolysaccharides.

Person-to-Person Transmission

• Skin-to-skin contact: Bacteria such as Staphylococcus aureus transmit Bacterial Diseases through direct contact.

• Droplets in the air: Tuberculosis and strep throat-causing bacteria are spread through sneezing and coughing. These are some of the most common bacterial diseases.

• Coughing and sneezing spread bacteria like those causing

• Sexual contact: Bacteria like Neisseria gonorrhoeae are transmitted through sexual contact.

Indirect Transmission

• Water and Food: Bacteria can be transmitted inside the body by consuming contaminated water and food.

• Contaminated Surfaces: Bacteria are present on the contaminated surface and can be transferred upon touching.

Transmission by Vectors

• Insects: Ticks are the carriers of bacteria such as Borrelia burgdorferi, which cause Lyme disease.

Bacterial Disease Symptoms

The common reaction to any bacterial infection is fever, which is one of the main symptoms. Other symptoms include pain, especially at the injection site, inflammation resulting in redness and swelling due to the immune system's reaction, and fatigue.

Disease-Specific Symptoms

• In cholera, dehydration and severe diarrhoea are the most common symptoms.

• In tuberculosis, night sweats, persistent cough and weight loss are the major symptoms of infection.

• In Lyme disease, joint pain occurs along with bullseye rashes.

Risk Factors Involved in Bacterial Diseases

Weakened immune systems, chronic diseases, inadequate hygiene care, and exposure to infected people or contaminated surroundings are the major risk factors for bacterial infections.

Diagnosis of Bacterial Diseases

Bacterial infections can be diagnosed by:

• Laboratory Tests: bacteria are cultured from blood, urine, and sputum samples.

• Clinical Examination: Examining past medical history and associated symptoms.

• Imaging: X-rays or CT scans check for internal damage or infections.

Treatment of Bacterial Diseases

• Antibiotics: They are considered first-line treatments. However, antibiotic resistance is a growing concern.

• Proper rest, Hydration and pain management relieve the symptoms.

• In severe cases, infected tissues are removed by surgery.

Prevention of Bacterial Diseases

• Vaccinations are effective against Bacterial diseases like whooping cough, tetanus, and pneumonia.

• Maintaining Hygiene: Hand washing before the meal, sanitizing the surface, and eating healthy food.

• Antibiotics must be used strategically to prevent resistance.

Tips, Tricks, and Strategies for Bacterial Diseases

It takes effort to remember everything in a single go. We made the entire problem easy. Some of the tricks regarding Bacterial Diseases are given below which you can use to memorise the important points.

Types of Bacterial Diseases

"TCS: Tuberculosis, Cholera, Syphilis"
T: Tuberculosis
C: Cholera
S: Syphilis
(These are three well-known bacterial diseases and provide an easy way to remember distinct types.)

Bacterial Disease Symptoms

"FVR: Fever, Vomiting, Rash"
F: Fever (common in many bacterial infections)
V: Vomiting (often occurs in bacterial gastrointestinal infections)
R: Rash (skin infections or secondary symptom of some bacterial diseases)
(Useful for recognizing general symptoms common in bacterial infections.)

Pathogenic Bacteria Types

"CSSP: Cocci, Spirilla, Spirochetes, and Bacilli"
C: Cocci (spherical bacteria like Streptococcus)
S: Spirilla (spiral-shaped bacteria like Campylobacter)
S: Spirochetes (long, spiral bacteria like Treponema that causes syphilis)
P: Bacilli (rod-shaped bacteria like Escherichia coli)
(Categorizes bacterial shapes and examples of each.)

Prevention of Bacterial Diseases

"SVH: Sanitation, Vaccination, Hygiene"
S: Sanitation (clean water and waste management)
V: Vaccination (immunization for certain bacterial diseases)
H: Hygiene (personal cleanliness to reduce infection risk)
(Highlights key preventive steps to reduce bacterial infections.)

Transmission of Bacterial Diseases

"CIA: Contact, Ingestion, Airborne"
C: Contact (skin contact, like in MRSA infections)
I: Ingestion (eating contaminated food, like Salmonella)
A: Airborne (inhalation, as in tuberculosis)
(Categorizes the main routes of bacterial transmission.)

Also Read