Healthcare professionals across geographies use geospatial technology as a weapon in their fight against dreaded diseases. Where are the new wars being fought and how is the geospatial arsenal helping humankind win them?
The recent partial government shutdown in the US threw the Center for Disease Control and Prevention (CDC) into a tizzy as it interrupted the publishing of the weekly influenza outbreak maps. “I am losing sleep now because I do not know if we will be able to find and stop things that might kill people,” said CDC Director Dr Thomas Frieden in an interview with CBS News early October. “What’s happening with flu? Where is it spreading? What types of flu are spreading? Is it in nursing homes or elsewhere? This really interferes with our ability to protect people.” And that is not all. CDC also has to worry about other outbreaks, including hepatitis A, salmonella, and measles.
It may be just one of the latest examples but the relation between diseases and locations is a lot older. Since the ancient times, the importance of location in outbreak and treatment of diseases has been paramount. While in the times of Hippocrates, physicians found out that people living near waterways would be more prone to malaria than those in drier areas. The efforts of one Dr John Snow in plotting the distribution of deaths during the infamous London cholera outbreak in 1854 laid the first groundwork for modern scientific epidemiology.
How geospatial technology helps
The use of location or geographical information in modern health care finds its roots in public health information or PHI, which means the application of information science and technology to public health practice and research. Better public health information leads to improved health geomatics where location is central, thus making Geographic Information System or GIS relevant and useful in health care. Primarily, it is applied in the areas of epidemiology, public health and medical geography. Spatial data is used to establish the correlation, or the lack of it, between location and health, and layers of useful information are added to show a relationship with local factors using a GIS.
“Infectious diseases that were formerly confined to remote areas now have the ability to expand their geographic range, jump species, become resistant to antimicrobial agents, and have become more virulent and frequent,” says Eddie Oldfield, Member, OGC. “The combination of geospatial data from earth observing systems and public health surveillance can be used to improve public health decision-making, policy-relevant analysis, and disease control,” he adds.
Today, mapping and field surveys are the most commonly used techniques, simply translating the patients’ addresses into longitudes and latitudes to pinpoint their location on earth. For example, the World Health Organization (WHO) generates maps to help healthcare agencies in understanding dengue and malaria incidence across the globe. “Early detection is crucial when people are being exposed to potentially fatal diseases, and geospatial technology enables us to detect and respond to diseases in time. Disease maps help the local officials in their fight against infectious diseases,” says Dr Atul Agarwal, who headed the polio programme in northern India under the aegis of Indian Academy of Pediatrics (IAP).
Researchers are also increasingly relying on remote sensing techniques to capture the signature characteristics of parasites and predict the spread of vector-borne diseases like malaria. These efforts are based on the fact that the spatial distribution of vectors is dependent on environmental conditions like temperature and humidity. The technique is coupled with ground surveys to determine and confirm the presence of parasites. Similarly, satellite imagery helps in finding out land-cover types and landscape elements such as larvae habitat, bloodmeal sources, breeding and resting sites of parasites. A review of the project ‘Enhancing USAID Famine and Malaria Early Warning with NASA Earth Science Results Project’ in Africa has estimated that around 10% of Botswana’s success in combating malaria could be attributed to the programme.
Internet search trends also play an important role in locating the presence of a particular disease, points out Google’s Chief Technology Advocate Michael Jones. For instance, if Google finds thousands of people searching for symptoms or treatment for a particular disease in a particular location within a span of few days, it informs the local healthcare authorities about a possible disease outbreak in that area. This is how Google provides WHO with a one-week early notice about flu all around the world. Google also offers online tools such as the Dengue Trends and Flu Trends.
WHO leads from the front
Today, frequent air travelling has given wings to communicable diseases. Since 1973, over 30 previously unknown diseases have emerged, including Legionnaire’s disease, HIV/AIDS, Hepatitis C, and H5N1 Influenza A or avian flu. The situation demands integrated efforts from multilateral agencies like the WHO and local governments.
The Global Health Observatory (GHO) of the WHO, which works as a global hub for mapping of diseases, has developed a map gallery on health topics ranging from influenza, dengue, cholera to neglected tropical diseases (NTDs). These maps not only talk about the current situation of disease spread but also define risk areas for the future. The WHO’s Global Health Atlas offers an online interface that allows users to select geographic areas and create maps of diseases, the location of health facilities, schools, roads, geographic features.
GHO also doubles as a source to develop health profile of each country which talks about the disease spread and carries information about intervention policies and strategies, government and external financing for disease control programmes, coverage and impact of diseases. While WHO is helping countries develop their national health maps, it has also been successfully using satellite imagery to predict outbreaks of epidemics. For instance, the Rift Valley Fever (RVF) outbreaks in Africa, Saudi Arabia and Yemen were found to be associated with above-average rainfall. The response of vegetation to increased levels of rainfall was monitored with the help of satellite imagery.
Map showing the spread of malaria across the globe
For years, WHO’s vaccination campaigns across the world have been using some form of maps or other geoinformation systems. “We use geospatial technology to map the existing healthcare facilities, huge urban areas and remote settlements,” says Dr Jeevan Kumar Makam, Medical Officer, WHO, Abuja, Nigeria. “We also use GIS for guiding implementation of public health programmes like polio, measles and disease surveillance activities,” he adds.
The Asian Development Bank (ADB) too plays an important role in advancing the cause of geospatial technology in health care. For instance, it supported the Department of Health in the Philippines to initiate the Women’s Health and Safe Motherhood Programme. The initiative went on to create the National Health Atlas with an aim at developing an integrated GIS database of health facilities, locations of which were recorded through a ground survey using hand-held GPS devices. The Philippines also developed the Maternal Health Modelling as a GIS-based application system and a model to gauge the effect of materials, supplies and services provided by different health facilities.
The UNICEF–GIS project is an interesting initiative, which relies on crowdsourcing to provide location-based information on diseases. Young individuals are trained to collect data about their neighbourhoods; UNICEF verifies the information and shares it through social and civic media channels to generate action for more child-friendly communities. These youngsters also help a city to find out the governmental and NGOs offering services related to health care.
How developed countries have benefitted
Most developed countries are able to use geospatial technology for better understanding of disease spread and hence take preventive measures, thanks largely to their well-developed infrastructure of information gathering. The US has a National Notifiable Diseases Surveillance System (NNDSS) managed by the Center for Disease Control and Prevention (CDC) which uses the Atlas for United States Mortality to monitor health factors such as spatial distribution of people to places with the best and worst air quality. As mentioned earlier, CDC is also involved in publishing weekly online reports with interactive maps.
NASA has for long played an important role in predicting and controlling diseases. According to John Haynes, Public Health Programme Manager for the NASA Earth Science Applied Sciences Program, “NASA satellite remote sensing technology has been an important tool in the last few years to not only provide scientists with the data needed to respond to epidemic threats quickly, but to also help predict the future of infectious diseases in areas where diseases were never a main concern.”
In the UK, the National Health Services (NHS) organisations are covered by the Ordnance Survey Public Servicethe public sector, allowing state organisations to use free and consistent geodata. The ‘NHS Atlas of Variation in Healthcare’ includes atlases of variation in health care for people with respiratory disorders, diabetes, kidney diseases etc. The Right Care programme coordinates with the London School of Economics to evaluate the impact of these atlases in benchmarking local healthcare practices.
Australia is another example, and the efforts here are spearheaded by the south-eastern state of Victoria. Victoria’s Department of Health first turned to geospatial technology in 2001 in its fight against the Legionnaires’ Disease. As soon as contaminated water cooling towers were found to be the source of the outbreak, the state partnered with Esri Australia to develop a GIS solution for an accurate view of the disease. Project team leader Stuart Adcock says the GIS layers showed patient and disease data over a map of information about the state’s water cooling towers. “Thanks to GIS, we are able to visualise patterns and relationships between seemingly unrelated factors, such as the proximity of a patient’s home to a contaminated water cooling tower,” he adds. Today, Australia leverages the benefits of geotech for its national healthcare directory and HealthDirect Australia, an organisation focused on managing e-health services. In addition, it is mapping things like obesity among children and mental health ‘hot-spots’. “By using GIS to identify where people are suffering from mental health problems, we can investigate why this is occurring and take required actions,” says Damien Cassin, Esri Australia’s GIS specialist in Health.
The European Union’s Malereo project, which aims at global eradication of malaria, relies on high-resolution EO data for generating maps on image bases, water bodies, vegetation indices and population density. Data of 0.5-1 metre is used for preparing household maps, vital for the success of Indoor Residual Spraying campaigns. These fill the gap when GPS-collected terrain data is not available. Malereo is developing a semi-automatic approach to extract household maps from satellite scenes.
The European Commission has also co-funded the EO- 2HEAVEN (Earth Observation and Environment Modelling for the Mitigation of Health Risks) research project to understand the relationship between environmental changes and their impact on human health. The €6-million, 40-month project was started in January 2010 and countries like Uganda and South Africa have been roped in to understand the implications of climate change for the emergence of infectious diseases.
What’s up with the rest?
Though on the uptake, developing and underdeveloped countries have only started to use location information in public health care. Even as emerging nations such as China, India or Russia have robust EO systems in place, their actual implementation in the health sector has been far from satisfactory, owing majorly to awareness and planning issues.
China had its first major brush with geospatial technology in healthcare services as recently as 2002 when it was hit by Severe Acute Respiratory Syndrome or SARS. Thankfully, the local medical community quickly understood that locating a communicable disease was the first step towards containing it. A SARS mapping website was built to collect information on the spread of disease in Hong Kong, China, and the rest of the world. Daily datasets were geocoded and presented as online maps that could be analysed. Updates were used to geocode case information against the street and building databases. People could know which buildings had, or were suspected as having, infected cases and which had been cleared. Over the entire duration of the crisis, the site produced more than 250,000 maps. Since then China’s march has been steady in this field.
In India, although maps and satellite data have been used in government vaccination campaigns for some time now, these efforts have been stray and far from coordinated, with the XII Five Year Plan (2013-17) only now emphasising on the use of geoinformation in healthcare management. Even as there is no consolidated programme on the ground so far, states such as Jharkhand have started taking initiatives to track healthcare professionals, ambulances and equipment. The state of Kerala has developed the ‘Geospatial Kerala Health Information System’, which not only maps healthcare resources such as public and private hospitals but also pinpoints the locations (catchment areas) of ambulances. The system further tells locations of all healthcare facilities with cardiology department or healthcare facilities with more than 25 beds or more than 15 doctors. Digital Mapping Laboratory under the Vector Control Research Centre in Pondicherry is using GPS to demarcate areas affected by dengue or malaria. “The laboratory does visual interpretation of the multi-spectral and multi-temporal satellite sensors data for mapping the mosquito breeding habitats. This not only helps in understanding the severity of the disease spread but also in evaluating the pressure on healthcare facilities and resources in the area,” says M. Palaniyandi of the Digital Mapping Laboratory. In addition, the WHO has also come up with a dengue map for the country which not only talks about the number of cases but also predicts the disease spread.
Location and mapping is playing a vital role in polio vaccination programmes across the globe. For example, the Global Polio Eradication Initiative, a public-private partnership led by national governments and spearheaded by the WHO, Rotary International, US CDC and UNICEF, is aggressively using geotechnology to gauge the effectiveness of the Short Interval Additional Dose approach in vaccination drives. Independent monitors collect near-real time data and analyse it through mobile phones and software to monitor the progress. For example, five vaccination teams in Karu ward, AMAC Local Government Area in the Federal Capital Territory of Abuja, Nigeria were equipped with GPS to track their movements during the day. Kathmandu in Nepal witnessed an initiative when scientists combined the DNA sequencing technology and GPS signaling data to map the spread of typhoid and trace its source.
Similarly, the University of the Philippines in Manila has used remote sensing technique to identify the environmental determinants of malaria and schistosomiasis, and develop prevalence maps. The country is also working on a national health map and malaria GIS maps.
In Brazil, WHO is collaborating with the government for continuous updation of the country’s health map. Researchers at the Federal University of Sao Paulo (UNIFESP) will soon start a project to map the geographic distribution of genetic auto inflammatory diseases in Sao Paulo. “The project will help in controlling the spread of auto inflammatory diseases,” says Dr Maria Teresa Terreri, Associate Professor, Division of Rheumatology, Department of Pediatrics UNIFESP. However, other Latin America and Caribbean countries are way behind. The Pan American Health Organization (PAHO) provides technical cooperation to the LAC countries to update the epidemiological information available for mapping and modelling of the neglected tropical diseases. WHO has created a Department of Control of Neglected Tropical Diseases (NTDs) and formulated the ‘Global plan to combat NTDs 2008–2015’, which emphasises on identifying gaps in epidemiological information and the priority geographic areas for intervention at sub-national levels. This helped reduce domestic transmission of Chagas disease.
The future of G-power
Determining location of health facilities, providing facilities at each location depending on local endemic health problems, and emergency routing during disasters are some other areas where geospatial technology is proving to be critical. These techniques are also helpful in developing the Spatial Decision Support System which, in turns leads to policy decisions. Realising the potential return on investment from location information-enhanced business intelligence, the private healthcare sector has also started experimenting with use of geoinformation.
»Business intelligence: With location becoming an integral part of business intelligence required to provide customer service, healthcare majors too have started using this technology to pinpoint the location of assets like ambulances and human resources, which helps in better emergency response and also saves costs. The technology is also helping healthcare groups to map where their patients are coming from and know more about prevalent diseases in different areas. For instance, Epworth Healthcare, a private healthcare group in Australia, used geospatial analytics to find the most underserviced area. The results prompted it to decide on a $447-million new facility next to Deakin University in the Melbourne satellite city of Geelong.
»Emergency response: Healthcare resources (such as therapy providers and pharmacies) in proximity to patients can be quickly located in case of emergency. Recently, the Stanford University Medical Center at Stanford in California used GIS to analyse the nurse population density of various geographic areas. The study helped in locating the nurses who were nearest to the patients, thus proving improved emergency response time and better healthcare services.
»Patient safety: GPS location tracker for patients with dementia or memory problems is an established norm now, with Alzheimer’s associations in nearly all countries advocating its use to ensure patient safety. Aged care homes and hospitals have also started using GPS devices for keeping tabs on patients.
»Mobile GIS: Geospatial technology is riding on mobile GIS too. For instance, the ArcGIS platform (which extends to iOS, Android and other mobile devices) can track assets, community workers and even patients. It is also capable of visualising real-time data on population movements captured by cellular and GPS networks. Similarly, HealthMap is an initiative by a team of researchers, epidemiologists and software developers at Boston Children’s Hospital in Massachusetts. It relies on data sources like online news aggregators, eyewitnesses, expert discussions and official reports for outbreak monitoring and real-time surveillance of emerging public health threats. Apart from this, online tools such as ‘Malaria Hotspots’ in the UK are not only mapping the spread of malaria, but are also uploading interviews of people who have recently visited the worst-hit countries.
Challenges to overcome
The promises are unending, but geospatial technology has to overcome a few crucial challenges to realise its full potential in the healthcare sector.
The lack of awareness about the applicability of the technology in health care is a huge challenge. It impedes the process of seamless integration of geoinformation and technology in the healthcare sector. “The high cost of implementing geospatial technology in healthcare and the lack of knowledge are the most critical bottlenecks and challenges,” emphasises Dr Makam. “The industry should focus on organising or sponsoring seminars, workshops and awareness activities. They should also rope in big universities and academic institutes to provide courses in GIS technology,” he adds.
Recording the exact location of a disease is another crucial problem. Most developing countries either do not have enough resources for data collection or the patients do not report their ailments at all due to remoteness of their location or affordability factor. “During 2003- 2009, we did not get accurate reports on polio cases in several remote villages of northern India. False reporting of vaccination drives was another major issue. Later, satellite maps provided by the National Polio Surveillance Project helped us in understanding the real scenario and eradicating polio from the country,” said Dr Atul Agarwal. Sometimes diseases are not properly diagnosed. For example, dengue and viral fever in northern India are often mistaken for each other. In certain countries, doctor-patient confidentiality laws can cause hindrance in proper reporting of a disease.
Further, various countries and organisations produce various kinds of data and the key challenge often is the integration of this diverse and distributed geospatial data. “Interoperable geospatial solutions could enable communication and decision-making between agencies such as WHO, public health authorities, research institutes etc to address inequities in access to health care,” says OGC’s Oldfield.
Currently, it is either multilateral agencies like the WHO or government departments which are using geospatial technology in healthcare services. In some countries, local healthcare agencies are not even aware of such advancements or possibilities. What is required is a multi-pronged approach by multilateral agencies, governments and the healthcare industry to first understand the potential of geospatial technology and then incorporate that in their basic planning stages for a safer, healthier human race.