Communicable and Non-Communicable Diseases

Communicable and non-communicable diseases affect all human beings at different stages of their lives. Health is essential for everybody’s life. Therefore, it is very important to understand the different types of diseases that can affect people.

• Communicable diseases are caused by infectious biological agents called pathogens. 
• They may be viruses, bacteria, fungi, and helminth parasites
• While non-communicable diseases are caused by non-infectious causes such as nutrient deficiency, lifestyle, genetics, and environmental pollution.
• The mode of transmission of diseases is through air, water, food, physical contact, or sexual contact. 
• HIV/AIDS is transmitted through sexual contact, from infected mother to her baby, blood transfusions, and by sharing injection needles. 
• Preventing and controlling communicable diseases through vaccination, proper sanitation, hygiene practices and personal protection is a must.

Key Terms: Health, Disease, Communicable Diseases, Non-Communicable Diseases, Infectious Diseases, Non-Infectious Diseases, Fungi, Bacteria

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What Is Health?

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Health is the state of physical, mental and social well-being of a person. The factor that affects health is a disease. 

• A disease can also be described as a condition of discomfort in the body. 
• The discomfort can either be due to a structural deformity or functional derailment in the body. 
• The person who studies diseases is called a pathologist. 
• They classify diseases based on several criteria. 
• Some of the criteria for classification of diseases are the duration of occurrence, communicability, type of causative agent and source of transmission.

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What is Disease?

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A disease is a metabolic derailment in an organism or a human being. Diseases are discomforts or abnormalities that occur due to damage to organs or organ systems in our body. The damage may be temporary or permanent. 

• The manifestations of these diseases are called symptoms. 
• Symptoms help pathologists and physicians in accurate diagnosis of the disease. 
• The diseases that are transmitted from person to person are called communicable diseases.

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Pathogens

Organisms that cause diseases are called pathogens. They may be prions, viruses, bacteria, protozoa, fungi and worms.

• The pathogens may enter a healthy body directly or indirectly through some agents called vectors. 
• They cause infectious or chronic diseases. Prions are viral protein particles. 
• They infect healthy people through improperly cooked meat Creutzfeldt-Jakob disease is a fatal disease that is caused by prions.

Salmonella bacteria

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Disease Types

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Diseases can be classified based on their mode of transmission, causal organisms, or duration. The different types are mentioned below:

Communicable Disease

Infectious diseases are spread from person to person. They are called communicable diseases. They are caused by harmful germs. The top communicable diseases are Tuberculosis, malaria, HIV/AIDS, Hepatitis, Measles, COVID-19, Common cold, Influenza (Flu), Poliomyelitis, and Chickenpox.

Communicable Disease

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Non-communicable Disease

Non-infectious diseases are not spread from person to person. They are called non-communicable diseases. 

• They are caused by a variety of reasons like genetics, nutritional deficiency, cancer-causing agents, lifestyles, age and sex. 
• Cancer, Diabetes, Heart disease, Chronic lung disease, Alzheimer’s disease, Hypertension, Asthma, Mental health ailments, Blindness, and Obesity, are examples of non-communicable diseases.
• Some diseases are transmitted through contaminated air, water, food, soil, and direct contact. 
• Based on transmitting agents, a disease can either be airborne, water-borne or food-borne.

Non-Communicable Disease(Obesity)

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Difference Between Communicable And Non-Communicable Diseases

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The major differences between communication and non-communicative diseases are tabulated below:

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Causes of Disease

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Diseases may be contagious or non-contagious. The contagious diseases spread from person to person through air, water, food, or vectors.

Airborne Diseases

Some microbes spread diseases through the air. This can be in the form of coughs and sneezes from the mouth of an infected person in the form of tiny droplets.

• The infected ambient air enters the breathing system of a healthy person who inhales this air and gets infected. 
• The common diseases that are spread through the air are – coronavirus, Common cold, Pneumonia, and Tuberculosis, Airborne diseases occur frequently in crowded ecosystems.

Waterborne Diseases

Diseases are also spread through water. This generally happens when fluids or excreta of an infected person get mixed with potable water. 

• Water contaminated with human excreta may cause cholera and diarrhoea. 
• Chlorination or boiling of drinking water keeps a check on water-borne diseases.

Foodborne Diseases

Diseases are also spread through uncovered or improperly covered food items. 

• This generally happens when house flies carry infected germs from the excreta of an infected person to the surface of exposed food products. 
• So it is always advisable to avoid eating exposed roadside food items.

Sexually transmitted Diseases

Diseases can also spread through physical or sexual contact with an infected person. Dreadful diseases like AIDS, Syphilis, and Gonorrhoea are STDs (Sexually Transmitted Diseases). 

• But these diseases are not spread through casual contact with an infected person such as hugs, handshakes, eating in their vicinity, playing sports etc.
• HIV causes AIDS. It is transmitted both through sexual contact, from infected mother to her baby, blood transfusions, and by sharing injection needles.

Vector Borne diseases

Animals act as disease hosts when they have the potential to carry pathogens without being affected. These kinds of animals are called vectors. 

• Sometimes they may act as intermediate hosts or secondary hosts also. 
• Mosquitoes are the most common insect vectors in the world.
•  Female Anopheles mosquitoes require nutrient-rich food to produce mature eggs. 
• So they bite vertebrate hosts and obtain the required nutrition by feeding on their blood. 
• Meanwhile, they transmit different kinds of diseases, especially Malaria. 

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Prevention Of Diseases

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The prevention and control of communicable diseases vaccination, proper sanitation, hygiene practices and personal protection. 

• The latter includes using masks, gloves, and condoms. 
• Early detection and treatment help in preventing the spread of these diseases.
• A balanced diet, regular exercise, and giving up smoking and drinking can reduce the risk of developing non-infectious diseases.

Read More:

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Things to Remember

• Health is the state of physical, mental and social well-being of a person.
• A disease can be described as a condition of discomfort in the body. A disease is a metabolic derailment in an organism or a human being.
• Organisms that cause diseases are called pathogens. They may be prions, viruses, bacteria, protozoa, fungi and worms.
• Infectious diseases are spread from person to person. They are called communicable diseases.
• Non-infectious diseases are not spread from person to person. They are called non-communicable diseases.
• The common diseases that are spread through the air are – coronavirus, Common cold, Pneumonia, and Tuberculosis.
• Water contaminated with human excreta may cause cholera and diarrhoea.
• Dreadful diseases like AIDS, Syphilis, and Gonorrhoea are STDs (Sexually Transmitted Diseases).

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Previous Year Questions

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