Communicable and Non-Communicable Diseases

Table of Contents

What are Communicable Diseases?

Communicable diseases, also known as infectious diseases, are the illnesses caused by microorganisms like bacteria, viruses, fungi, or parasites.
Communicable diseases are considered as the ‘Contagious burden’.
Communicable diseases are those types of diseases, usually triggered by some bacteria, viruses or some other kinds of pathogens, which transfers from one individual to another individual through various routes i.e. interaction with body fluids, inhalation of an airborne virus, insect bites, etc.
These diseases can be transmitted from one person to another, either directly (e.g., through physical contact or droplets) or indirectly (e.g., via contaminated surfaces, water, or vectors like mosquitoes).
Communicable diseases greatly affect the low- and middle-income countries (LMICs).

Modes of Transmission of Communicable Diseases

Direct transmission: Touching, kissing, or sexual contact (e.g., HIV/AIDS, gonorrhea)
Airborne transmission: Coughing or sneezing (e.g., tuberculosis, COVID-19)
Vector-borne transmission: Through organisms like mosquitoes (e.g., malaria, dengue)
Waterborne and foodborne transmission: Contaminated water or food (e.g., cholera, typhoid)

Examples of Communicable Diseases

Prevention and Mitigation Measures of Communicable Diseases

Development of screening programs
Isolation of various infectious diseases
Environmental hygiene campaigns
Vaccination programs focusing on specific areas
Chemoprophylaxis
Community diagnosis
Upholding a healthy lifestyle.
Maintaining Food hygiene and public health hygiene
Water sanitation
Controlling Overcrowding.
Ensure vector control
Health education

What are Non-Communicable Diseases (NCDs)

Non-communicable diseases (NCDs) are chronic diseases that are not generally transmitted from person to person through direct or indirect ways.
Non- communicable diseases are those types of diseases, usually triggered by a change in dietary pattern, lifestyle, nutrient deficiency, hereditary, allergy, etc. that are not transferable from one individual to another individual.
NCDs are generally considered as the ‘Silent Epidemic’.
NCDs usually progress slowly and results from a combination of genetic, physiological, environmental, and behavioral factors.
NCDs are mainly linked to lifestyle choices and aging of a person.
NCDs are responsible for over 70% of all global deaths, with the majority of those deaths occurring in Low- and Middle-Income Countries (LMICs).
The burden of NCDs badly affects the healthcare systems and reduces economic productivity due to premature mortality and long-term disability of its citizens.

Examples of Non-Communicable Diseases

Cardiovascular diseases: Heart attacks, stroke and hypertension
Cancers
Diabetes
Parkinson’s disease
Autoimmune diseases

Risk Factors of Non-Communicable Diseases

Behavioral factors: Use of tobacco, unhealthy diet, physical inactivity, and harmful use of alcohol.
Metabolic/physiological factors: High blood pressure, obesity, high cholesterol, and insulin resistance.
Environmental factors: Exposure to pollution, occupational hazards, and socio-economic stress.

Prevention and Mitigation Measures of Non-Communicable Diseases (NCDs)

Promotion of healthy lifestyle
Screening and early detection of disease
Confronting risk factors and taking necessary measures to mitigate those risk factors
Policy interventions like establishment of tobacco control protocols, high taxation on sugary products, banning of tobacco advertisements etc.
Health system strengthening focusing on all the building blocks of health system
Strong surveillance system and population-centered prevention
Promotion of mobile-based technologies.
Health campaigns and health education

Major Communicable and Non-Communicable Diseases

Communicable Disease	Infectious Agent	Symptoms	Period of communicability	Mode of transmission	Risk factors for increased transmission
FOOD OR WATER-BORNE DISEASES
Diarrheal diseases	Bacteria: such as Salmonellae and Escherichia coli	vomiting, diarrhea or bloody diarrhea, abdominal pain, fever, and chills, leads to dehydration	Temporary Salmonella carriers can last to exist for some months	Fecal-oral route, particularly contaminated water and food	Overcrowding Food unavailability Poor access to health care Lack of safe water and poor hygiene and sanitation. Lack of immunization.
Bacillary dysentery	Bacterium: Shigella dysenteriae type 1 causes the most severe disease		Asymptomatic carriers exist
Cholera	Bacterium: Vibrio cholerae		During the symptomatic phase until 2-3 days after recovery.
Typhoid fever	Bacterium: Salmonella typhi		Symptomatic period for 2 weeks. 10% of untreated patients stay carriers for several months.
Poliomyelitis	Enterovirus group: types 1,2,3		From 36 hours after infection, for 4-6 weeks	Highly communicable. person-to-person transmission via the fecal-oral route
RESPIRATORY-BORNE DISEASES
Acute Lower Respiratory Infections	Bacteria: Streptococcus pneumoniae and Haemophilus influenzae.	Difficulty in breathing Asthma Pneumonia Coughing up blood	Depends on the infective agent. Usually during the symptomatic phase.	Airborne/ Direct contact	Overcrowding Poor access to health care Food unavailability
Measles	Measles virus		4 days before the rash until 1-2 days after rash onset
Tuberculosis (TB)	Mycobacterium tuberculosis		Bacilli are discharged in the sputum.
Meningococcal disease	Bacterium: Neisseria meningitidis serogroups A, B, C,Y, W135		Asymptomatic carriers
VECTOR-BORNE DISEASES
Malaria	Protozoan parasite: Plasmodium vivax Plasmodium falciparum	sore muscles skin rash nausea stomach pain swelling of your lips, tongue, or face	stay infected for some years with P. vivax if inefficiently treated	Mosquito bite	Overcrowding Population movement Poor access to health care Unhygienic environment Malnutrition
Dengue	Flavivirus group		mosquito bite
Lymphatic Filariasis	Culex quinquefasciatus		Adult worms layer in lymphatic vessels and interrupt lymphatic system. Worms can live for nearly 6-8 years
Crimean-Congo	Nairovirus group		Linked to the presence of the infected rodents and fleas	Tick-borne/ direct contact with infected people, infected domestic animals.
ZOONOTIC DISEASES
Rabies	Rhabdovirus	High fever, rapid pulse, and severe difficulty breathing follow in two to five days.	Bite of infected mammalian species i.e. dog, cat, fox, etc.	The transmission is related to the bite of an infected animal	Overcrowding Poor access to health care. Uncooked meat Contact with infected animals.
Anthrax	Bacterium: Bacillus anthracis	Gastrointestinal pain	contact with tissues of an infected animal
BACTERIAL DISEASES
Trachoma	Chlamydia trachomatis	Mild itching and irritation of the eyes and eyelids Discharge from the eyes containing mucus or pus Eyelid swelling	contact with the eyes, eyelids, and nose or throat secretions of infected people	Direct contact with infected people.	Overcrowding Poor access to health care Lack of hygiene and sanitation. Unhygienic environment.

Non-communicable diseases

Cause

Symptoms

Risk Factors

Alzheimer’s Disease

Dementia

Memory loss

Delusions

Depression

Mood swings

Hereditary

Down syndrome

Mild cognitive impairment

Past head trauma

Asthma

Respiratory infections

Airborne substance and pollutants

Gastroesophageal reflux diseases

SOB

Coughing/ wheezing attacks

Chest tightness

Allergic condition

Exposure to chemicals.

Cataracts

Tissues contained by the lens break and clouding small areas of the lens.

Dim vision

Sensitivity to light

Eye injury

Excessive use of corticosteroid medications

Chronic Kidney Disease

Diabetes

High blood pressure

Glomerulonephritis

Kidney infection

Changes in urination

Muscle twitches and cramps

Swelling of feet and ankles

Diabetes

High blood pressure

Cardiovascular disease

Chronic Lung Disease

Chronic bronchitis

Emphysema

SOB

A prolonged cough produces mucus that may be clear, white, yellow or greenish

The Blueness of the lips or fingernail beds

Asthma

Age

Genetics

Smoking

Exposure to smoke, dust, and chemicals

Diabetes

Imbalance in insulin level resulting in type-1 and type-2 diabetes

Frequent urination

Extreme hunger

Blurred vision

Slow-healing sores

Family history

Gestational diabetes

Fibromyalgia

Genetics

Infections

Mental or physical trauma

Fatigue

Widespread Pain

Cognitive difficulties

Migraine

Painful bladder syndrome

Rheumatoid arthritis

Osteoarthritis

Heart Diseases

Heart Arrhythmia

Diabetes

High blood pressure

Drug abuse

Chest discomfort

Heart attack

Stroke

High cholesterol level

Diabetes

Obesity

Radiation and chemotherapy

Congenital heart defects

Medical conditions, medications and gene

Cardiomyopathy

Thickening or enlarging of the heart muscle

Valvular Heart Disease

Rheumatic fever, infections

Hypertension (High Blood Pressure)

Effect of the underlying condition

Chronic kidney disease

Visual change

Dizziness

Nosebleeds

SOB

Existing health conditions

Alcohol, tobacco use

Ethnicity

Obesity

Inactivity

Unhealthy eating habits

Measured through BMI

Certain medications

Inactivity

Medical problems

Genetics

Osteoporosis

Low sex hormones

Medical conditions

Lack of calcium

Back pain

Bone fracture

Stooped posture

Hormone levels

Steroid and other medications

Dietary factors

Cancer

Exposure to a carcinogenic substance

Environmental, viral or genetic factors

Breast changes

Bladder changes

Bowel changes

Neurological problems

Radiation exposure

Smoking

Alcohol

History of cancer

Hereditary

Major Differences Between Communicable and Non-Communicable Diseases

Feature	Communicable Diseases	Non-Communicable Diseases
Cause	Infectious agents	Genetic, environmental, behavioral
Transmission	Yes (person-to-person or indirect)	No
Duration	Often short-term	Usually long-term and chronic
Prevention	Vaccination, hygiene, vector control	Lifestyle changes, early screening
Global burden	High in developing countries	High worldwide, especially aging populations

Integrated Approaches to Prevent Communicable and Non-Communicable Diseases

Prevention of communicable and non-communicable disease through parallel approach requires plenty of resources and investment. Considering the double burden of disease, present global scenario demands joint and integrated approaches to prevention of communicable and non-communicable diseases. Some of the major integrated approaches to prevent communicable and non-communicable diseases are:

Strengthening Primary health care (PHC) systems: PHC must be targeted and strengthened to provide both prevention and treatment services.
Universal health coverage (UHC): UHC is essential to ensure that the financial barriers do not prevent the access to health services.
Multisectoral collaboration: It involves different sectors like education, agriculture, urban planning, and finance for jointly tackling the underlying determinants of both communicable and non-communicable diseases.
Health education and promotion: It should be focused at the community levels can empower individuals to make informed health choices and recognize early symptoms of diseases.

References and For More Information

https://www.medicalnewstoday.com/articles/234590.php

http://apps.who.int/disasters/repo/7394.pdf

https://www.who.int/nmh/topics/en/

https://www.mayoclinic.org/diseases-conditions/trachoma/symptoms-causes/syc-20378505

https://www.mayoclinic.org/diseases-conditions/diabetes/symptoms-causes/syc-20371444

https://www.mayoclinic.org/diseases-conditions/copd/symptoms-causes/syc-20353679

https://www.mayoclinic.org/diseases-conditions/alzheimers-disease/symptoms-causes/syc-20350447

https://www.mayoclinic.org/diseases-conditions/asthma/symptoms-causes/syc-20369653

https://www.mayoclinic.org/diseases-conditions/cataracts/symptoms-causes/syc-20353790

https://www.mayoclinic.org/diseases-conditions/chronic-kidney-disease/symptoms-causes/syc-20354521

https://www.paho.org/salud-en-las-americas-2017/?p=1391