Curbing infant mortality rates using innovation
In medicine and clinical care, it is common to periodically perform tests to measure a patient’s health. A physician might perform a weekly blood pressure measurement, an annual cholesterol level test, an annual exam to determine vision status and eye health, and frequent “well-baby” checks. In public health, where the “patient” is a group, community, or population of people, such a periodic assessment of health status or factors contributing to health and disease is called disease surveillance or risk factor surveillance.
As with a physician using patient tests in a clinical setting, the goal of the public health practitioner using disease surveillance methods is to learn something that will identify a problem (such as increased numbers of people with fever, cough, and/or fatigue in a population that might suggest an influenza outbreak). Thus, we look for a change in the numbers of people with worrisome symptoms; ideally, we try to do this in a defined population so that we can compare rates of illness (e.g., typically two per cent of the population has influenza symptoms but current disease surveillance indicates a five per cent occurrence rate of symptoms). The public health professional uses surveillance data to determine a course of action to promote the good health of a targeted population, usually by engaging a community, and occasionally a country or global region. For example, the increased rates of fever and cough found through disease surveillance may lead to laboratory confirmation of influenza, which in turn, may lead to timely recommendations for anti-viral medication use and immunisation campaigns.
Disease surveillance has served global public health well. For example, the decline of childhood deaths by the tens of millions due to childhood immunisations has involved a combination of strategic public health programs, disease surveillance, and effective vaccines. In India and most other nations, the successful eradication of smallpox and the elimination of polio have relied on the identification of disease cases such as characteristic skin lesions for smallpox and reporting of flaccid paralysis for polio.
One relevant new surveillance system, which we believe will have broad useful implications, is the Child Health and Mortality Prevention Surveillance (Champs) network. Deaths in children under the age of five will be identified and studied using a mixture of approaches. A seven-country surveillance system has been developed — six in sub-Saharan Africa, one in Bangladesh and another under consideration for India, which has regions with very high child mortality. The information of interest is determining the specific causes of death in children. Several innovative approaches and technologies are being employed to obtain more specific information on the causes of death. A technique for obtaining internal tissue for study is an approach called minimally invasive tissue sampling (MITS), which uses a hollow needle to remove a sliver of organ tissue from a deceased person for analysis. This tissue is then studied using immunohistochemical staining to specifically identify causative microbial pathogens.
The combination of the MITS approach and the special stains are a new state-of-the-art approach for this new surveillance system. The goal is to obtain much more specific evidence for identifying the cause of death in young children. The data so gathered could be utilised for more informed policymaking which will help prevent, to a considerable extent, the six million largely preventable deaths of young children that happen around the world, every year.
Surveillance, which began as a way to detect infectious diseases in a timely manner, has over time been also used to detect changing levels of environmental contamination (air pollution), injury hazards (such as for auto safety), radiation exposure, occupational exposures and behavioural risk factors for disease (for example, tobacco, physical activity, diet). Surveillance systems have also been open to improvements using the latest technologies for laboratory testing, such as genomic analysis and innovative (but lowtech) approaches, e.g. using reports and articles from news media, supermarket sales information, etc.
India has had remarkable success in improving its children’s health through the use of surveillance systems, particularly in polio. It is increasingly capable of contributing novel approaches and technological advances to disease and risk surveillance, that will improve its own population’s health and that of the world.
Deaths in children under the age of five will be identified and studied using a mixture of approaches. A seven-country surveillance system has been developed
Koplan is the Vice President for Global Health and Professor of Medicine and Public Health at the Emory University. Iyer is Senior Scientific Advisor at the Bill and Melinda Gates Foundation. He was previously the CEO of Shantha Biotech, and Head of Research and Development at Biocon