Communicable and non-

communicable diseases

Dr. Irniza Rasdi

What kills more people: infectious diseases or non-communicable diseases?

• Non-communicable diseases were responsible for 68% of all deaths globally in 2012.

• The 4 main NCDs are cardiovascular diseases, cancers, diabetes and chronic lung diseases.

• Communicable, maternal, neonatal and nutrition conditions collectively were responsible for 23% of global deaths,

• Injuries caused 9% of all deaths.

Are cardiovascular diseases the number 1 cause of death throughout the world?

• Cardiovascular diseases killed 17.5 million people in 2012, that is 3 in every 10 deaths.

• Of these, 7.4 million people died of ischaemic heart disease and 6.7 million from stroke.

Do most NCD deaths occur in high-income countries?

• 28 million of the 38 million of global NCD deaths in 2012 occurred in low- and middle-income countries.

• In terms of proportion of deaths that are due to NCDs, high-income countries have the highest proportion – 87% of all deaths were caused by NCDs.

• Followed by upper-middle income countries (81%).

• The proportions are lower in low-income countries (37%) and lower-middle income countries (57%).

What are the main differences between rich and poor countries with respect to causes of death?

• In high-income countries, 7 in every 10 deaths are among people aged 70 years and older.

• People predominantly die of chronic diseases: cardiovascular diseases, cancers, dementia, chronic obstructive lung disease or diabetes.

• Lower respiratory infections remain the only leading infectious cause of death. Only 1 in every 100 deaths is among children under 15 years.

What are the main differences between rich and poor countries with respect to causes of death?

• In low-income countries, nearly 4 in every 10 deaths are among children under 15 years, and only 2 in every 10 deaths are among people aged 70 years and older.

• People predominantly die of infectious diseases: lower respiratory infections, HIV/AIDS, diarrhoeal diseases, malaria and tuberculosis collectively account for almost one third of all deaths in these countries.

• Complications of childbirth due to prematurity, and birth asphyxia and birth trauma are among the leading causes of death, claiming the lives of many newborns and infants.

How has the situation changed in the past decade?

• Ischaemic heart disease, stroke, lower respiratory infections and chronic obstructive lung disease have remained the top major killers during the past decade.

• Noncommunicable diseases (NCDs) were responsible for 68% (38 million) of all deaths globally in 2012, up from 60% (31 million) in 2000. Cardiovascular diseases alone killed 2.6 million more people in 2012 than in the year 2000.

• HIV deaths decreased slightly from 1.7 million (3.2%) deaths in 2000 to 1.5 million (2.7%) deaths in 2012. Diarrhoea is no longer among the 5 leading causes of death, but is still among the top 10, killing 1.5 million people in 2012.

• Tuberculosis, while no longer among the 10 leading causes of death in 2012, was still among the 15 leading causes, killing over 900 000 people in 2012.

• Maternal deaths have dropped from 427 000 in the year 2000 to 289 000 in 2013, but are still unacceptably high: nearly 800 women die due to complications of pregnancy and childbirth every day.

• Injuries continue to kill 5 million people each year. Road traffic injuries claimed nearly 3500 lives each day in 2012 – more than 600 more than in the year 2000 – making it among the 10 leading causes in 2012.

Why do we need to know the reasons people die?

• Measuring how many people die each year and why they died is one of the most important means – along with gauging how diseases and injuries are affecting people – for assessing the effectiveness of a country’s health system.

• Cause-of-death statistics help health authorities determine their focus for public health actions. A country where deaths from heart disease and diabetes rapidly rise over a period of a few years, for example, has a strong interest in starting a vigorous programme to encourage lifestyles to help prevent these illnesses. Similarly, if a country recognizes that many children are dying of malaria, but only a small portion of the health budget is dedicated to providing effective treatment, it can increase spending in this area.

• High-income countries have systems in place for collecting information on causes of death in the population. Many low- and middle-income countries do not have such systems, and the numbers of deaths from specific causes have to be estimated from incomplete data. Improvements in producing high quality cause-of-death data are crucial for improving health and reducing preventable deaths in these countries.

Definitions

• Communicable disease: a disease that can be spread to a person from another person, an animal or object. Ex: common cold, influenza, mononucleosis, etc.

• Non-communicable disease: a disease that can NOT be spread from person to person. Ex: cancer, heart disease, cirrhosis, etc.

Definitions Continued

• Disease: Any condition that interferes with the normal or proper functioning of the body or mind.

• Not all types of fungi, bacteria, viruses and protozoa are disease-causing agents

• Germs: The microorganisms that cause diseases. They are so small they can only be seen through a microscope.

A case is a risk factor …

Infection in one person can be transmitted to others

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What is infectious disease?

Infectious Diseases are Caused by

Pathogens

What’s a pathogen?

Aetiology

• This is the study of what causes a disease.

• It is basically how scientists/doctors pinpoint what created the disease in order to better understand how to cure it or prevent it from spreading.

Disease is the result of forces within a dynamic system consisting of:

agent of infection hostenvironment

Epidemiologic Triad

Agent

Host

Environment

• Age• Sex• Genotype• Behaviour• Nutritional status• Health status

• Infectivity• Pathogenicity• Virulence• Immunogenicity• Antigenic stability• Survival

• Weather• Housing• Geography• Occupational setting• Air quality• Food

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Factors Influencing

Disease Transmission

Epidemiologic Triad Concepts

• Infectivity – ability to invade a host

(# infected / # susceptible) X 100• Pathogenicity – ability to cause disease

(# with clinical disease / # of infected) X 100• Virulence – ability to cause death

(# of deaths / # with disease (cases)) X 100

•Chain of Infection

Chain of Infections

Modes of Disease Transmission

• Direct contact

• Indirect contact

• Droplet

• Airborne

Direct Contact Transmission

• Microbes directly transferred from an infected person to another person

• Examples• Contact with blood or other body fluids

• Ungloved contact with a scabies-infested patient

• Ungloved contact with wounds or mucous membranes

Indirect Contact Transmission

• Microbes transferred through contaminated intermediate object/living things

• Examples• Healthcare personnel not performing adequate hand hygiene

between patients

• Sharing medical equipment without cleaning or disinfection between patients

• Defective medical equipment allowing for inadequate disinfection or sterilization

Vector

• The item that transfers the pathogen to its host.

• Vectors are “vehicles” that transport pathogens from one host to another.

• Examples: water, blood, ticks, mosquitoes…

Droplet Transmission

• Respiratory droplets carrying infectious pathogens• Generated during coughing, sneezing, talking, or certain medical

procedures (e.g. suctioning)

• Droplets traditionally defined as > 5 µm

• Typically refers to distances within 3 feet of infected patient

Airborne Transmission

• Dissemination of droplet nuclei containing infectious agents

• Dispersed over long distances

• Face-to-face contact not required

• Special ventilation systems are required to prevent airborne transmission

Think about it:Where Do Pathogens Hide When

Not Infecting People and Animals?The soilBodies of waterSurfaces like farm equipmentThe skin of people and animalsIn the airIn body fluids

Where are those

pathogens?

Susceptible

Susceptible host

Dynamics of infectiousness

Latentperiod

Infectious period

Non-infectious

Infe

ctio

n

Time

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Timeline for Infection

Subclinical disease

Clinical Death/recovery

Incubation

Timelines for Infection and Disease

Latent period: time interval from infection to development of infectious (note: this definition differs from that used for non-infectious diseases).

Infectious period: time during which the host can infect another host.

Incubation period: time from infection to development of symptomatic disease.

Symptomatic period: period in which symptoms of the disease are present.

Infections

Endemic: Habitual presence of a disease in a given geographic area.

Epidemic: Occurrence of a group of illnesses of similar nature within a given community or region in excess of normal expectancy, and derived from a common or from a propagated source.

Pandemic: A worldwide epidemic.

Herd immunity: Resistance of a group of to an attack by a disease to which a large proportion of members of the group are immune.

Chain of Infection Filariasis

The painful and profoundly disfiguring visible manifestations

of the disease, lymphoedema, elephantiasis and scrotal swelling

occur later in life and lead to permanent disability. These

patients are not only physically disabled, but suffer mental, social and financial losses contributing

to stigma and poverty.

Immune System

• The Immune System is a combination of body defenses made up of cells, tissues, and organs that fight pathogens in the body.• It’s purpose is to help you get better when you

are ill and to prevent you from becoming ill in the first place.

How does our body protect us from pathogens?

• Our body is an amazing machine which has five main barriers (first line of defense) for keeping our body healthy. They are:

• Skin – acts as a protective barrier

• Mucous Membranes – line the mouth, nose, throat, eyes and other body parts. These trap germs. Coughing and sneezing gets rid of the germs trapped by these mucus membranes.

• Saliva – contains enzyme that destroy many harmful organisms.

• Tears – wash away germs. Contains enzymes that kill some harmful organisms.

• Stomach Acid – acid kills many germs

Antigens and Antibodies

• What’s the difference between the two?• Antigens: a substance that sends your

immune system into action when your body is invaded by pathogens. The body sees these as “invaders”.

• Antibodies: proteins that attach to antigens, keeping them from harming the body. How our body responds to antigens, by producing antibodies – our body’s “army of soldiers”.

Iceberg Concept of Infection

• What kills more people: infectious diseases or noncommunicable diseases?

• Are cardiovascular diseases the number 1 cause of death throughout the world?

• Do most NCD deaths occur in high-income countries?

• WHO often says that smoking is a top cause of death. Where does tobacco use affect these causes of death?

• What are the main differences between rich and poor countries with respect to causes of death?

• How has the situation changed in the past decade?

• How many young children die each year, and why?

Non communicable

diseases

Introduction

• Non-communicable diseases are the leading killer today and are on the increase.

• Nearly 80% of these deaths occurred in low- and middle-income countries.

• More than nine million of all deaths attributed to noncommunicable diseases (NCDs) occur before the age of 60.

• Around the world, NCDs affect women and men almost equally.

Introduction

• The leading causes of NCD deaths were: • cardiovascular diseases (17 million deaths, or 48% of NCD

deaths);

• cancers (7.6 million, or 21% of NCD deaths); and

• respiratory diseases, including asthma and chronic obstructive pulmonary disease (COPD), (4.2 million). Diabetes caused an additional 1.3 million deaths.

Cardiovascular diseases

• Cardiovascular disease is caused by disorders of the heart and blood vessels, and includes coronary heart disease (heart attacks), cerebrovascular disease (stroke), raised blood pressure (hypertension), peripheral artery disease, rheumatic heart disease, congenital heart disease and heart failure.

• Although heart attacks and strokes are major killers in all parts of the world, 80% of premature heart disease and stroke is preventable

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Cardiovascular diseases:Contributing factors

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A person’s genetic make-up The foundations of adult health are laid in early lifeSocioeconomic groupMental healthDietOverweight and obesityInactivityTobaccoAlcoholDiabetesGlobalization and urbanization

Cancer

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• Cancer is the uncontrolled growth and spread of cells that arises from a change in one single cell.

• The change may be started by external agents and inherited genetic factors and can affect almost any part of the body.

• The transformation from a normal cell into a tumour cell is a multistage process where growths often invade surrounding tissue and can metastasize to distant sites.

Common cancers in Malaysia

Cancer: Interaction between a person’s genetic factors and any of three categories

of external agents

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• Physical carcinogens; such as ultraviolet and ionizing radiation or asbestos;

• Chemical carcinogens; components of tobacco smoke, aflatoxin (a food contaminant) and arsenic (a drinking-water contaminant);

• Biological carcinogens; such as infections from certain viruses, bacteria or parasites.

Cancer: risk factors for cancer

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• tobacco use• unhealthy diet• insufficient physical activity• the harmful use of alcohol• Infections (hepatitis B, hepatitis C (liver cancer), human

papillomavirus (HPV; cervical cancer), Helicobacter pylori (stomach cancer)

• Radiation• variety of environmental and occupational exposures of

varying importance

Chronic respiratory diseases

• According to the WHO Global Status Report on NCDs 2010, smoking is estimated to cause about 71% of all lung cancer deaths and 42% of chronic respiratory disease worldwide.

• Second-hand smoke causes severe respiratory health problems in children, such as asthma and reduced lung function

• Indoor air pollution from biological agents related to damp and mould increases the risk of respiratory disease

Diabetes

• Diabetes is a chronic disease that occurs when the pancreas does not produce enough insulin (a hormone that regulates blood sugar) or alternatively, when the body cannot effectively use the insulin it produces.

• The overall risk of dying among people with diabetes is at least double the risk of their peers without diabetes.

• About 347 million people worldwide have diabetes.

Diabetes

• Total deaths from diabetes are projected to rise by more than 50% in the next 10 years.

• In developed countries most people with diabetes are above the age of retirement,

• whereas in developing countries those most frequently affected are aged between 35 and 64.

Health Care System in Malaysia

Health care system in Malaysia

ASSIGNMENT 2

1. Choose a disease/illness

2. Choose a traditional treatment available for the disease/illness

3. Describe in detail about the treatment related to the chosen illness

4. Explain how does the treatment may improve or treat the selected illness.

Thank you