Conquering Malaria

Joel G. Breman, MD, DTPH

Fogarty International Center

National Institutes of Health

Improving Population Health Workshop

Instituto Nacional de Salud Publica (INSP)

Cuernavaca, Mexico

21 – 22 June 2003

Conquering Malaria

• Burden

• Ecology and manifestations

• Successes

• Control

• Research and training

Burden

The Global Burden of Malaria

1.5 – 2.7 million deaths annually Over 1 billion clinical episodes 300 – 500 million people infected Every 10 - 30 seconds a child dies of malaria

Ecology and Manifestations

Malaria Ecology

Intrinsic and Extrinsic Factors

Controland prevention

measuresHuman

Parasite Mosquito

Social, behavioral, economic and

political factors

Environmental conditions

EXTRINSIC

INTRINSIC

Malaria’s Toll: Major Intrinsic Components

Plasmodium falciparum

Anopheles gambiae

Malaria Ecology and BurdenClinical Manifestations

Infected Mosquito

Infected Human

Chronic effects

Anemia

Neurologic/ cognitive

Developmental

Impaired growth and development

Malnutrition

Acute febrile illness

Severe illness

Hypoglycemia

Anemia

Cerebral malaria

DeathRespiratory distress

Pregnancy

Fetus

MaternalAcute illness

AnemiaImpaired productivity

Low birth weight Infantmortality

MARA/ARMA Model of Malaria Transmission, 2003

Successes

• 1899-1914, multiple demonstrations of control by reduction of Anopheline larvae and adults– 1899, Sierra Leone (antilarval); Cuba (large-

scale); Malaysia (antilarval)– 1904-1914, Panama Canal Zone; control by

larviciding, large-scale environmental modification

• 1927, elimination of A. albimanus in Barbados (first area-wide success with invading species)

Successes: Vector Control

Successes: Vector Control (2)

• 1935-1939, use of pyrethrum spraying in South Africa, Netherlands and India

• 1939-1957– 1939-1940, Elimination of A. gambiae from

Brazil and upper Nile, Egypt, 1942-1945– 1946-1957, Interruption of transmission by

anti-mosquito measures in Cyprus, Sandinia, Guyana, Venezuela and Greece; indoor residual spraying with DDT, a new major strategy

Successes: Personal Protection (3)

• 1987-2003– Multiple projects and programs using

insecticide-impregnated bed nets demonstrating overall mortality reduction and decrease in several malaria indices

Control

Vector Control

• Drainage and filling: urban*

• Chemical and biological larvicides*

• Indoor residual insecticide spraying*

• Outdoor residual insecticide spraying

*costly and effective

Personal protection (2)

• Insecticide–impregnated materials:nets, curtains, clothing*

• House screening• House location• Repellents• Fumigants

* Cost-effective for low-income countries

Antiplasmodial (3)

• Patient management: early diagnosis, treatment, referral, education

• Chemoprophylaxis• Intermittent treatment (pregnancy)*• Radical therapy for relapses (P. vivax, P.

ovale)

* cost effective

Social Action (4)

• Mobilization of individual, family, community• Health education

Management Effectiveness• Health systems: access, use, quality• Leadership: policies, strategies, tactics• Surveillance of infection and disease• Monitoring and evaluation of programs

Research and Training

Research, Training, and Support Needs Research, Training, and Support Needs According to Understanding of Diseases According to Understanding of Diseases andand

Efficacy of Control MethodsEfficacy of Control Methods

Research Needs

Efficacy of

Control Methods

High HighTraining

Some HighModerateResearch Support Needs

Low Low

Research, Training, and Support Needs Research, Training, and Support Needs According to Understanding of Diseases According to Understanding of Diseases andand

Efficacy of Control MethodsEfficacy of Control Methods

Research Needs

Efficacy of

Control Methods

High HighTraining

Some HighModerateResearch Support Needs

Low Low

SmallpoxGuinea wormPoliomyelitisH. influenzae type BMeaslesTetanus

Malaria Dengue

HIV/AIDSTuberculosis

Ebola/Marburg InfluenzaCancers

Alzheimer’s

Research Agenda• Pathogenesis

• Drug development

• Immunology and vaccine development

• Diagnostics

• Entomology

• Recent genetic breakthroughs

Conquering Malaria

For More InformationFor More Information

MIM http://mim.nih.govRBM http://www.who.intDCPP http://www.fic.nih.gov/dcpp/Joel Breman jbreman@nih.gov