Global health Issue

Global Health 101

Chapter Eleven Communicable Diseases

The Importance of Communicable Diseases

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

• Disproportionately affect the poor • Enormous economic consequences • Relevance to Millennium Development Goals

(MDGs) • Burden of communicable disease is unnecessary,

many can be prevented or treated • http://www.healthmap.org/en/

Key Terms, Definitions, and Concepts

• Communicable disease- transmitted from animal to animal, animal to human, or human to human

• Spread and contracted through food, water, bodily fluids, vector, inhalation, nontraumatic contact, and traumatic contact

• Controlled with vaccination, mass chemotherapy, vector control, improved water and sanitation, improved care seeking and disease recognition, case management, and behavioral change

Table 11.2: Communicable Disease Definitions

The Burden of Communicable Diseases

• 36% of total deaths, 40% of total DALYs lost annually in low- and middle-income countries

• Relative importance compared to noncommunicable diseases and injuries varies by region

• South Asia and sub-Saharan Africa have highest relative burden of deaths from communicable diseases

• Relative importance of specific communicable diseases varies by region, age group

Table 11.3: Leading Causes of Death from Selected Communicable Diseases, 2001, by Number of Deaths

in Thousands

Figure 11.1: Deaths from Selected Infections and Parasitic Diseases, as Percent of Total Deaths, by

Region 2001

Source: Adapted from United Nations. Millennium Development Goals. Available at: http://www.un .org/millenniu mgoals/goals. Accessed July 11, 2006.

http://www.map.ox.ac.uk/explorer/

Table 11.4: Leading Causes of Death in Low- and Middle-Income Countries

The Costs and Consequences of Communicable Diseases

• Constrain health and development of children, having an effect on education and productivity

• Strong stigma and discrimination associated with HIV, TB, and others

• Limit productivity of adult workers • Costs of treatment burden families • High rates reduce investment in a country’s

development

The Leading Burdens of Communicable Diseases

The Burden of Emerging and Re-Emerging Infectious Diseases

• Resistant forms of disease emerge or re-emerge when bacteria, parasites, and viruses are genetically altered

• Critical global health problems because they can arise anywhere, at anytime, and spread rapidly

• Drug resistance limits ability to treat infection • https://youtu.be/8swAWixSQPs

Table 11.9: Key Factors Contributing to the Emergence and Re-emergence of Infectious Diseases

The Leading Burdens of Communicable Diseases

Consequences of Emerging and Re- Emerging Infectious Diseases

• Direct costs of treating disease • Indirect costs include declines in tourism and

trade • Increased costs of treating a drug resistant case

HIV/AIDS

The Burden of HIV/AIDS • Spread through unprotected sex, birth or

breastfeeding, blood, or transplanted tissues • Attacks the immune system, leaving the body

susceptible to opportunistic infections • Main routes of transmission vary by location • Highest rates are in Central and Southern

Africa

Table 11.12: HIV/AIDS Basic Facts

U.S. HIV/AIDS Map

African-Americans with HIV/AIDS

Health Insurance and AIDS

HIV/AIDS

The Costs and Consequences of HIV/AIDS • Enormous impacts in high prevalence countries that go

beyond morbidity and mortality • A person with full-blown AIDS cannot work and will

become dependent on others for care • Creates exceptional number of orphans • Highly stigmatized condition • http://www.msnbc.com/msnbc/watch/caught-on-

camera-act-up-part-1-264235587758 • Direct cost of treatment high for the poorest countries

HIV/AIDS

Addressing the Burden of HIV/AIDS • Focus on prevention of new infections • Successful efforts have included strong political

leadership and open communication • Approach to prevention must vary with nature of

epidemic • Efforts need to combine education and behavioral

change, bio-medical approaches, and structural approaches

HIV/AIDS

Critical Challenges in HIV/AIDS • Developing a vaccine to prevent the 2.6

million new infections per year • Cost-effective approaches to prevention in

different settings • Universal treatment for all those who are

eligible • Management of TB and HIV coinfection

Tuberculosis

• 8th most important cause of death worldwide • Spread through aerosol droplets • HIV dramatically increases chance of

developing active TB • Risk factors include living in crowded

circumstances, undernutrition, inadequate health care

• Increase in multi-drug resistant cases

Table 11.13: TB Basic Facts: 2009

Tuberculosis

The Costs and Consequences of TB • Costs to families, communities, and countries

is very high • Large number of people sick, long course of

illness • Stigmatized condition • Economic growth of a country inversely

correlated with the rate of TB

Tuberculosis

Addressing the Burden of TB Directly Observed Therapy, Short-Course

(DOTS) • Political commitment to TB program • Access to quality-assured sputum spears and

microscopy • Standardized regimens of directly observed

chemotherapy • Regular supply of TB drugs • Monitoring and evaluation for program supervision

Tuberculosis

Management of TB/HIV Co-infection • TB is an opportunistic infection of HIV • Leading cause of death of adults who are HIV-

positive and not on antiretroviral therapy • WHO recommends testing all HIV-positive

people for TB, and all those with TB for HIV

Tuberculosis

Challenges in TB Control • Need for more effective vaccines, inexpensive

and rapid diagnostics, and drug therapy that will lessen duration of treatment

• Improving identification and treatment of MDR-TB and XDR-TB

• Linking providers of TB diagnosis and treatment with a national TB control program

Malaria

• 2.9% of global DALYs lost annually • 9th leading cause of death in low- and middle-

income countries • Sub-Saharan African children account for 98% of

global burden of malaria • Caused by parasites carried from one person to

another by Anopheles mosquito • Pregnant women and fetuses are at high-risk of

anemia and death from malaria

Malaria

Costs and Consequences of Malaria • Individuals often have malaria up to 5 times

per year • Indirect costs are greater than direct costs of

treatment because due to lost days of work • Roll Back Malaria suggests that economic

costs in countries with a high burden are equal to 1.3% of GDP per year

Malaria

Addressing the Burden of Malaria • Prompt treatment of those infected • Intermittent preventative therapy for pregnant

women • Long-lasting insecticide-treated bed nets for

people living in malarial zones • Indoor residual spraying of homes • Getting artemisinin, a new drug, into use to delay

advent of resistance

Malaria

Challenges in Addressing Malaria • 100% coverage for people at risk with bed nets,

indoor residual spraying, and intermittent therapy for pregnant women

• Encouraging behavioral change to ensure bed nets are being used properly

• Bridging gaps in diagnosis and treatment • Developing a safe, effective, affordable vaccine • New drugs to keep up with drug resistance

Diarrheal Disease

The Burden of Diarrheal Disease • Responsible for about 1.5 million deaths per year-

20% of all childhood deaths • Significant decline over past 30 years due to

better nutrition, disease recognition, oral rehydration therapy

• Most significantly impacts the poor because of poor housing, lack of refrigeration, poor personal and community hygiene

Diarrheal Disease

Addressing the Burden of Diarrhea Disease prevention strategies: • Promotion of exclusive breastfeeding for the first 6 months • Improved complementary feeding, introduced at 6 months • Rotavirus immunization • Measles immunization • Access to clean water supply and sanitation Case management interventions: • Oral rehydration therapy • Zinc supplementation • Antibiotics

Neglected Tropical Diseases

The Burden of Neglected Tropical Diseases

• More than 1 billion people infected with one or more of the NTDs

• Most common afflictions of world’s poorest people

• Impede child development, harm pregnant women, cause long-term debilitating illness

Table 11.14: The Major Neglected Tropical Diseases, Ranked by Prevalence

Figure 11.3: Countries with Five or More Neglected Tropical Diseases

Neglected Tropical Diseases

The Consequences of the Neglected Tropical Diseases

• Major impact on health including, but not limited to blindness, anemia, growth retardation, and permanent disability

• Increase susceptibility to other infectious diseases • Social stigma • Impact on productivity

Neglected Tropical Diseases

Addressing the Neglected Tropical Diseases • Rapid-impact package of drugs for the seven most

common NTDs • Guinea worm- teaching people to filter water • Trachoma- SAFE strategy • Lymphatic filariasis- annual administration of

donated drugs • Periodic de-worming of young children

Neglected Tropical Diseases

Future Challenges • Hookworm and schistosomiasis vaccine • Develop new drugs to combat the NTDs more

effectively and combat resistance • Introduce underlying risks such as hygiene,

unsafe water supply, worm and parasite breeding sites

Future Challenges to the Control of Communicable Diseases

• Continued cooperation in and among countries to combat infectious diseases

• Strengthening health systems in low- and middle-income countries

• Sustained political and financial support • Strengthening surveillance at local, national and global levels • Adequately trained and appropriately deployed human

resources • Reaching a balance between prevention and treatment • Technical challenges including new vaccines, treatment and

diagnostics