Faculty of Medicine

Public Health (31505291) الصحة العامة Lecture 14

Global overview of Communicable Diseases

By

Hatim Jaber MD MPH JBCM PhD

24-7-2018

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1. The global health impact of mental health and mental diseases. Drug abuse and Addictive substances

1. Global overview of communicable diseases 2. Global overview Non- communicable diseases(NCDs)- 3. The global health impact of Hepatitis, Tuberculosis and HIV/AIDS 4. The global health impact of Cardiovascular Diseases , Diabetes and

Obesity 1. Health service delivery in developing countries 2. Health policy, Health priorities 3. Health systems and financing 4. Quality of care and effectiveness in different health services systems; 5. Health policies and management within a global health perspective 1. Violence and injuries 2. Migration and Travelers' health

We can End Polio!

• Polio cases worldwide:

1988: 350000 2016: 27

• Since 1988, we have reduced polio cases by

99.9%.

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Presentation outline 24-7-2018

Time

Introduction of concepts 09:15 to 09:25

Current trends an occurrence of global infectious diseases

09:25 to 09:35

Current trends an occurrence of global infectious diseases

09: 35 to 09:40

Barriers to Immunization Coverage 09:40 to 09:50

Basic principles and policies for prevention and control at global level

09:50 to 10:15

Challenges: Emerging infectious diseases

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Future Population Growth Will be in LICs and MICs

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

9,000

10,000

1950 1960 1970 1980 1990 2000 2010 2020 2030 2040 2050

Y e a r

Total population (millions)

D eveloping countries

D eveloped countries

Causes of Death Vary Greatly by Country Income Level

Age distribution of death in Denmark around 2005

Male Female

80 60 40 20 0 20 40 60 80

0 - 4

15 - 19

30 - 34

45 - 49

60 - 64

75 - 79

90 - 94

Age g

roup

Percent of total deaths

Age distribution of death in Sierra Leone around 2005

Male Female

80 60 40 20 0 20 40 60 80

0 - 4

15 - 19

30 - 34

45 - 49

60 - 64

75 - 79

90 - 94

Age g

roup

Percent of total of deaths

A total of 2797 international health hazards by type and

country, January 2001–September 2013.

Christopher Dye Phil. Trans. R. Soc. B 2014;369:20130426

Communicable Diseases: Definition

• Defined as

• “any condition which is transmitted directly or indirectly to a person from an infected person or animal through the agency of an intermediate animal, host, or vector, or through the inanimate environment”.

Communicable Diseases: Definition • A communicable disease is one that can be

transmitted from one person to another.

It is caused by an agent that is infectious (capable of

producing infection) and is transmitted from a source,

or reservoir, to a susceptible host.

A communicable disease: A disease or illness in a

susceptible host, caused by a potentially harmful

infectious organism or its toxic byproduct.

Communicable disease spreads due to contact

between an infectious agent and a susceptible host

Communicable Diseases: Definition

• Transmission is facilitated by the following – more frequent human contact due to

• Increase in the volume and means of transportation (affordable international air travel),

• globalization (increased trade and contact)

– Microbial adaptation and change

– Breakdown of public health capacity at various levels

– Change in human demographics and behavior

– Economic development and land use patterns

How are infections spread?

• From person to person

• Through viruses, bacteria and parasites

More than a third of the world’s

population is infected with worms!

CD- Modes of transmission • Direct

• Blood-borne or sexual – HIV, Hepatitis B,C

• Inhalation – Tuberculosis, influenza, anthrax

• Food-borne – E. coli, Salmonella,

• Contaminated water- Cholera, rotavirus, Hepatitis A

• Indirect

• Vector-borne- malaria, onchocerciasis, trypanosomiasis

• Formites

• Zoonotic diseases – animal handling and feeding practices (Mad cow disease, Avian Influenza)

Importance of Communicable Diseases

• Significant burden of disease especially in low and middle income countries

• Social impact

• Economic impact

• Potential for rapid spread

• Human security concerns

• Intentional use

2015 statistics

• The latest number of deaths due to HIV and AIDS per year stood at some 1.1 million. Thus, HIV/AIDS was one of the communicable diseases causing the most fatalities worldwide.

• As of 2015, an overwhelming portion of the countries with the highest prevalence of HIV worldwide were located in Africa.

• Similarly, the region of Africa is also disproportionately affected by malaria, accounting for 191,000 of the 212,000 cases reported worldwide in 2015.

Communicable Diseases account for a significant global disease burden

• In 2005, CDs accounted for about 30% of the global BoD and 60% of the BoD in Africa.

• CDs typically affect LIC and MICs disproportionately.

• Account for 40% of the disease burden in low and middle income countries

• Most communicable diseases are preventable or treatable.

• Even with the projected rise in the burden of NCDs, CDs are expected to account for 26% of the BoD in 2015 globally, and 56% in Africa. (Global Burden of Disease

Communicable Disease Burden Varies Widely Among Continents

Communicable disease burden in Europe

CDs have a significant social impact • Disruption of family and social networks

– Child-headed households, social exclusion

• Widespread stigma and discrimination – TB, HIV/AIDS, Leprosy – Discrimination in employment, schools, migration

policies

• Orphans and vulnerable children – Loss of primary care givers – Susceptibility to exploitation and trafficking

• Interventions such as quarantine measures may aggravate the social disruption

CDs have a significant economic impact in affected countries

• At the macro level – Reduction in revenue for the country (e.g. tourism)

• Estimated cost of SARS epidemic to Asian countries: $20 billion (2003) or $2 million per case.

• Drop in international travel to affected countries by 50-70%

• Malaria causes an average loss of 1.3% annual GDP in countries with intense transmission

• The plague outbreak in India cost the economy over $1 billion from travel restrictions and embargoes

• At the household level – Poorer households are disproportionately affected

– Substantial loss in productivity and income for the infirmed and caregiver

– Catastrophic costs of treating illness

International boundaries are disappearing

• Borders are not very effective at stopping communicable diseases.

• With increasing globalization

• interdependence of countries – more trade and human/animal interactions

• The rise in international traffic and commerce makes challenges even more daunting

• Other global issues affect or are affected by communicable diseases.

• climate change

• migration

• Change in biodiversity

Human Security concerns

• Potential magnitude and rapid spread of outbreaks/pandemics. e.g. SARS outbreak

– No country or region can contain a full blown outbreak of Avian influenza

• Bioterrorism and intentional outbreaks

– Anthrax, Small pox

• New and re-emerging diseases

– Ebola, TB (MDR-TB and XDR-TB), HPAI, Rift valley fever.

The ten leading causes of death in the world in 2011 according to the World Health Organization

Causes of death: Developed and

developing countries

The pie graphs show the different causes of death between developed and developing regions of the world. These areas correspond closely with the non-industrialised and industrialised parts of the world. As the graph shows, the majority of people in Developing regions die of communicable diseases, while in developed regions deaths are due largely to non-communicable diseases.

Communicable and non-

communicable diseases

• Worldwide, one death in three is the

result of an infectious disease

• Almost all the deaths from infectious

disease occur in the non-industrialised

world.

• The biggest killers in the industrialised world are non infectious diseases

Number of deaths caused by selected communicable diseases annually worldwide as of 2015 (in 1,000)

Deaths from infectious diseases (plus maternal and nutritional

disorders) and non-infectious diseases (including injuries) worldwide,

1990–2050.

Christopher Dye Phil. Trans. R. Soc. B 2014;369:20130426

Trends in direct financial assistance for health,

1990–2010, measured in US$ billions per year (log scale), with five of

the principal areas of investment.

Christopher Dye Phil. Trans. R. Soc. B 2014;369:20130426

A paradigm shift - Enlightened Self interest

• Communicable diseases have no borders. • Predominantly affect the poor, and poor countries

• Also affect richer households and countries.

• Interventions are non-rival, non-exclusive and have positive externalities.

• Elimination and control of certain communicable diseases increases global health security.

• Limited financial incentives for the market to drive needed innovation in research and drug development

• Mismatch between global health need and health spending

• Global health security is therefore inextricably tied to the effective control of CDs in developing world.

Resurging diseases

• Resurging diseases are those communicable diseases

that have been endemic in some parts of the world but are now endemic in more countries and are increasing to epidemic proportions in others.

• Often, the resurgence is caused by the emergence of new, drug-resistant strains of a familiar organism, such as the MDR TB bacillus. Staphylococcus aureus infections have some strains so powerful that they are not responding to vancomycin any longer; they still respond to two new antibiotics, but those could also lose effectiveness.

Global Mismatch Between Disease Burden and Health Spending

Burden of disease in disability adjusted life years by income

category

9.7%55.9%

34.4%

% DALYs in LIC % DALYs in MIC % DALYs in HIC

Approaches to Interventions

1. Personal Responsibility and action

2. Utilitarian Approaches – “Greatest good for the greatest number”

Including non Health Systems Interventions.

3. Regulations and Laws

4. Partnerships and Collaboration

5. Enlightened Self Interest

Personal Responsibility and action

• Improved hygiene and sanitation

– Hand washing, proper waste disposal, food preparation and handling.

• Information, education and behavior change

– Changing harmful household practices

– Livestock handling, knowledge about contagion

• Cultural and social norms

• Self reporting of illnesses and compliance with interventions and treatment.

Utilitarian Approaches – “Greatest good for the

greatest number”

• Reliance on personal responsibility • not always the optimal option given different knowledge levels and

values. • Public good nature of the interventions

• Social Isolation and Quarantine measures • Home treatment; Isolation

• Mass vaccination programs and campaigns • Polio, small pox, DPT, Hepatitis, Yellow fever

• Mass treatment programs – • Onchocerciasis, de-worming programs.

• For some CDs, intervention in other sectors is required • Environmental health – elimination of breeding sites, spraying • Agricultural practices such as poultry handling and exposure to soil

pathogens during farming.

Regulations and Laws

– National response remains the bedrock of intervention

• National laws and capacities vary.

– International Regulations and laws introduced

• 1851 – International Sanitary regulations in Europe following cholera outbreak

• 1951- international sanitary regulation by WHO.

• 1969- Replaced by the International Health regulation

– Minor changes in 1973 and 1981

– cholera, plague, yellow fever, smallpox, relapsing fever and typhus

• 2005 – Revised International Health Regulation

– Challenge of enforceability of international agreements.

Regulation and laws – WHO 2005 International health regulation

• IHR (2005) is a legally binding agreement among member states of WHO to cooperate on a set of defined areas of public health importance.

• Arrived at by consensus of all member countries of WHO, with clear arbitration mechanisms

• Its elements include – Notification:

– National IHR Focal Points and WHO IHR Contact Points

– Requirements for national core capacities

– Recommended measures

– External advice regarding the IHR (2005)

Partnerships and Collaboration

• Collaboration vs. coercion

• Importance of partnerships –

– MDG 8: “Develop global partnerships for development”

– Comparative advantage of partners

– Inclusiveness

• Examples of partnerships

– Over 70 Global health partnerships available

• Examples include the Stop-TB program, GFATM, RBM, UNAIDS, GAVI, Global Outbreak Alert and Response Network (GOARN), GAIN, bilateral and multilateral organizations.

Key principles of an Effective Global

Response

• Respect for the value of each life

– Behind every statistic is an individual

– Understanding of the social context that govern individual decision making

• Disease Surveillance and reporting

• Management and containment of outbreaks

• Strong legal and regulatory framework

• Sustained and predictable financing

• Building national health systems

World Bank’s involvement

• Relevance to our mandate

– CDs disproportionately affect the poor and LICs and MICs

– Enormous economic consequences

– Major constraint to achieving the MDGs

• Major source of financing for poor countries

– This position is rapidly changing with the entrance of newer players in DAH such as Gates foundation, Bilaterals, multilaterals.

– Call for innovative financing schemes

World Bank

• $ 430 million committed to malaria booster projects in Africa

• By 2008, 21 million bed nets and 42 million ACT doses would have been distributed.

• As of June 2007, the World Bank had approved financing of $377 million for 40 projects in 45 countries in all six geographic regions to combat Avian influenza

• Cumulative WB commitment to HIV/AIDS is over $ 2.5 billion

Sources of Development Assistance for Health

0

2,000

4,000

6,000

8,000

10,000

12,000

Average 1997-99 2003

Year

US$ (

in m

illi

on

s) Private Non-profit

Other Multilateral

Development Banks

UN System

Bilateral

Source: Michaud 2006

The World Bank’s new Strategy for Health, Nutrition, and Population

(HNP) strategy • Five broad strategic directions of the World bank

1. Focus on HNP Results

2. Strengthening health systems

3. Ensuring synergies between Health Systems strengthening and priority disease interventions

4. Intersectoral approach to HNP results

5. Increase strategic and selective engagement with development partners.

• Despite significant declines in mortality, communicable

diseases are responsible for persistently high morbidity

among various age and population groups.

• Rates of some communicable diseases, especially

tuberculosis (TB) and sexually transmitted diseases

(STDs), remain disproportionately high in selected

population groups (in some cases, shockingly high), a

fact often masked when statistics are aggregated.

•

Globally emerging communicable

diseases.

•Communicable diseases have challenged health care providers for centuries. •They have led to the development of countless nursing and medical preventive measures, from simple procedures such as hand-washing, sanitation, and proper ventilation to the research and development of vaccines and antibiotics. •Communicable diseases, particularly those of epidemic and pandemic proportions, such as TB and acquired immunodeficiency syndrome (AIDS), continue to cost millions of lives and billions of dollars

to the global human society every year.

Evolution of Communicable Disease Control

Global Trends :The following are

some of the major accomplishments: .

1995, more than 80% of the world’s children had been immunized against diphtheria, tetanus, whooping cough, poliomyelitis, measles, and TB, compared with fewer than 5% in 1974

Global eradication of smallpox was achieved in 1980 Because of improved sanitation and hygiene, outbreaks of relapsing fever, transmitted by lice, are rare today.

Reported cases worldwide of poliomyelitis have declined by 99% since the campaign began, with only 537 new cases in the world in 2001.

Malaria remains a major threat, even though the mortality rate has improved in the last 25 years. In 1954, there were 2.5 million deaths annually and 250 million cases of malaria worldwide; in 2002, there were an estimated 1.5 to 2.7 million deaths and 300 to 500 million cases.

Communicable Disease Control

PRIMARY PREVENTION In the context of communicable disease control, two approaches are

useful in achieving primary prevention:

(1) education using mass media and targeting health messages to

aggregates

(2) immunization.

SECONDARY PREVENTION There are two approaches to secondary prevention of communicable

disease:

(1) screening

(2) contact investigation, partner notification, and case-finding Tertiary Prevention The approaches to tertiary prevention of communicable disease include

isolation and quarantine of the infected person and safe handling and control

of infectious wastes.

Barriers to Immunization Coverage (1)Religious Barriers.

(2)Financial Barriers

(3)Social Barriers

(4)Cultural Barriers

(5)Philosophical Objections

(6)Provider Limitations

Communicable Disease Control

Worldwide coverage of eight vaccines used in the

Expanded Programme on Immunization, 1980–2012 [66].

Christopher Dye Phil. Trans. R. Soc. B 2014;369:20130426

Ten great public health achievements worldwide (2001–2010)

1. Reductions in child mortality 2. Tuberculosis control 3. Vaccine-preventable diseases 4. Control of neglected tropical diseases 5. Access to safe water and sanitation 6. Tobacco control 7. Malaria prevention and control 8. Increased awareness and response for improving global

road safety 9. Prevention and control of HIV/AIDS 10. Improved preparedness and response to global health

threats

Global strategies/plans adopted by the World Health Assembly (WHO’s governing body)

Communicable diseases • 2015--WHA68.2 Global technical strategy and targets for malaria

2016–2030, WHA68.6 Global vaccine action plan WHA68.7 Global action plan on antimicrobial resistance • 2014---WHA67.1 Global strategy and targets for tuberculosis

prevention, care and control after 2015 • 2013---WHA66.12 Neglected tropical diseases (including the Global

Plan to Combat Neglected Tropical Diseases 2008–2015)WHA66.8 Comprehensive mental health action plan 2013–2020

• 2012--WHA65.17 Global vaccine action plan • 2011---WHA64.14 Global health sector strategy on HIV/AIDS, 2011–

2015 • 2010-- WHA63.13 Global strategy to reduce the harmful use of

alcohol