Infectious diseases, including HIV/AIDS, tuberculosis, malaria, polio, and several neglected tropical diseases (NTDs) are easily spread through personal contact, water, and air, (many NTDs are vector borne transmitted by mosquitoes, flies, etc) and are a particularly significant problem in developing countries. In the past, infectious diseases have been widespread in developing countries and chronic diseases were found primarily in high income countries. However, the global pattern of disease burden is shifting. While infectious disease still remains a major problem in many countries, chronic diseases, including such noncommunicable conditions as cardiovascular disease, cancer, diabetes and respiratory disease, are now the major cause of death and disability, not only in developed countries, but also worldwide. The greatest total numbers of chronic disease deaths and illnesses now occur in developing countries.
The U.S. commitment to combat infectious diseases has saved lives and reduced human suffering throughout the developing world. Through the President's Emergency Plan for AIDS Relief (PEPFAR), for example, the U.S. supports lifesaving treatment for over 1.7 million people worldwide and has enabled 200,000 children to be born HIV-free. The 2008 reauthorization of PEPFAR expands the U.S. commitment to $48 billion over 5 years to combat HIV/AIDS, tuberculosis, and malaria.
In addition to HIV/AIDS, tuberculosis (TB) remains a global public health problem and is one of the three leading causes of deaths worldwide due to infectious diseases. In light of this, the U.S. is on the frontline of the battle against tuberculosis (TB). In collaboration with host nation TB programs, the U.S. works to improve the quality of basic TB programs or DOTS (Directly Observed Therapy, Short Course) services; upgrade laboratory infrastructure; build a foundation to introduce new diagnostic technologies; and work with the World Health Organization (WHO) and other partners to conduct drug resistance surveys and surveillance. The U.S. Agency for International Development (USAID) is the lead USG agency in international TB control programs, with PEPFAR taking the lead role in TB/HIV co-infection, and the U.S. Department of Health and Human Services, Centers for Disease Control and Prevention (HHS/CDC) providing critical technical support to global and country level initiatives. The National Institutes of Health (NIH) is engaged in basic and bioclinical international TB research. From 2000 to 2007, the U.S. provided nearly $600 million for TB programs worldwide. The U.S. also supports TB control worldwide through funding provided to the Global Fund to Fight AIDS, TB and Malaria (Global Fund), to which the U.S. is the largest single donor.
The U.S. also supports the fight against malaria through the President's Malaria Initiative (PMI), a five-year program run by USAID to reach those in 15 of the hardest-hit countries in Africa with the goal of reducing malaria-related deaths by 50 percent. In its second year, PMI reached 25 million people with treatment and prevention services and is working to reach the goal of reducing malaria-related deaths by 50 percent in 15 focus countries in Africa.
Prevention of infectious disease benefits people and contributes to health security. In 1988, for example, polio was endemic in more than 125 countries and paralyzed 350,000 children each year. Since then, the world has made remarkable progress toward polio eradication and only four countries remain endemic for polio transmission. The U.S. has contributed to this accomplishment by providing nearly thirty percent of global contributions to the Global Polio Eradication Initiative and funding 500 million doses of oral polio vaccine for distribution in endemic countries.
Along with some of the more commonly known infectious diseases, Neglected Tropical Diseases (NTDs), are truly devastating to many developing countries. These largely preventable diseases continue to pose a major threat to health and economic growth in many developing countries. In 2008, the United States launched a new initiative, challenging the world to reduce, control, and eliminate the threat of neglected tropical diseases. The U.S. committed $350 million over five years to treat over 3 million people in Africa, Asia, and Latin America suffering from NTDs. The initiative targets seven major NTDs including: lymphatic filariasis (elephantiasis); schistosomiasis (snail fever); trachoma (eye infection); onchocerciasis (river blindness); and three soil-transmitted helminthes (STHs hookworm, roundworm, whipworm).
Another example of the potentially devastating effects of infectious disease can be found in the 2003 outbreak of Severe Acute Respiratory Syndrome (SARS), which cost Asian economies between $11 and $18 billion, resulting in a GDP loss of between 0.5% and 2%. The emergence or re-emergence of other infectious diseases such as pandemic influenza could possibly exact a higher toll, both human and economic.
Other infectious diseases requiring national and international attention include dengue fever, measles, yellow fever, and Ebola virus.
Strong health systems within countries, including effective surveillance systems and adequate human resources, are fundamental to curb the spread of infectious disease and to provide early warning of new disease outbreaks.
Non-communicable diseases (NCDs), such as cancer, heart disease, lung disease, and diabetes, are now the major cause of death and disability worldwide. By 2020, NCDs are expected to account for 7 of every 10 deaths in the world, as they already do in the U.S. These projections suggest that NCDs and the death, illness, and disability they cause will soon dominate health care costs and are causing public health officials, governments and multinational institutions to rethink how we approach this growing global challenge.
According to statistics from the World Health Organization, non-communicable diseases are responsible for 63% of deaths worldwide, double the number of deaths from infectious diseases (including HIV/AIDS, tuberculosis, and malaria), maternal and perinatal conditions, and nutritional deficiencies combined. The principal known causes of premature death from NCDs are tobacco use, poor diet, physical inactivity, and harmful alcohol consumption.
Although NCDs make up a greater proportion of deaths and illnesses in developed countries, overall the greatest numbers of non-communicable disease deaths and illnesses occur in the developing world. Eighty percent of NCD-related deaths worldwide occur in low- and middle-income countries. Apart from the tremendous adverse effects on the quality of life of individuals involved, these conditions place enormous strains on family and community budgets. The overall economy suffers from both the labor units lost due to death and illness as well as the high direct medical costs. This phenomenon, during which health infrastructures already weakened by continuing battles with infectious disease are increasingly being taxed by rapidly growing NCDs, is often referred to as the double disease burden.
Greater advocacy is required to raise global awareness of this growing threat and to help dispel some of the myths surrounding NCDs. NCDs can be prevented, and they affect not only high-income countries, but middle- and low-income countries as well. Preventing and controlling NCDs will require countries to strengthen their health systems, but the effort cannot stop there; a truly effective response will require action well beyond the health sector. Health practitioners, policymakers, community members and industry leaders must work together in a multilateral fashion to create comprehensive solutions to this growing challenge.