Malaria, one of the most common diseases affecting people in the tropics, has made a comeback. Epidemics are increasing, despite decades of control programs in various countries around the world.

Preventing or remedying malaria's spread is difficult. In hot, humid climates, people are exposed to the elements, often living in houses constructed of mud grass and bamboo. This gives little protection against the malaria-carrying female Anopheles, who is insatiable in her quest for the blood needed for her eggs to mature. It is also a huge challenge to control insect numbers, as those mosquitos can breed anywhere -- even in water filling an animal's hoofprint.

Malaria cases are increasing rapidly in Brazil. From 1980-1991, reported confirmed cases more than tripled from 169,871 to 533,360, according to the Brazilian Ministry of Health. Malaria causes serious illness and death. Those people with malaria who do not die from the illness are nonetheless rendered quite sick, physically weak and unable to work due to the recurring fever and fatigue. The widespread death and illness caused by malaria is a serious roadblock to development.

In the Amazon, where 90% of the Brazilian incidence of malaria occurs, the spread of the disease has put a stop to the development of key mineral and agricultural potential. Surveillance, prevention and control measures are no longer effective. Areas once cleared of malaria are developing new outbreaks and developing stronger resistance to insecticides and the antimalarial drugs. Despite more than 30 years of work by SUCAM -- the division of the Ministry of Health that has been responsible for malaria surveillance and control -- the disease is increasing too quickly for the agency to effectively contain its spread.

In an effort to address the problem, researchers at the Federal University of Rio de Janeiro's (UFRJ) biomedical engineering department have developed a computer software program called SIG-MALARIA, designed for malaria surveillance. It uses a microcomputer-based image information system to evaluate malaria in municipalities. It also produces information to be used for decision-making in the prevention and control of the disease.

In future, the software will be used at SUCAM's regional offices as a tool to improve malaria control at both the regional and central levels in Brazil. The Pan American Health Organization has expressed interest in using the software and in helping with future stages of its development.

The development of this software -- funded by UFRJ and the International Development Research Centre (IDRC), with SUCAM providing necessary field and lab data -- represents a big step forward for planners. It factors in important variables which have never been part of the analysis before, but which affect disease prevention and control.

For example, malaria is linked to such factors as climate, the amount of water in a given area, and devastation of forests. "If there is forest, that means men are not close to bodies of water where the insects breed, and the insects will contact animals instead of humans," says Professor Fernando Infantosi, a senior researcher with the project. "During the process of deforestation, when there are more people around, the disease can spread a lot."

This is also true of mining regions. "Miners are very exposed and the probability of getting malaria is extremely high. In some regions in the northern state of Rondonia, 80% of the population has had malaria at least once," he says.

IMMEDIATE ANSWERS NEEDED

The SIG-MALARIA software also helps planners by providing comprehensive, reliable malaria data at the regional level. "Local people don't have the tools to process data," says Infantosi. "So the main idea of this project is to try and develop an instrument that can be used locally in the field, in one municipality, one that is user friendly and will provide the people working there with immediate answers about their data -- for example, is the disease on the increase, and if so, by how much? - - so they know whether to be on the alert for an epidemic and take action."

In the past, SUCAM's painstakingly-collected data from regional centres was often wasted. Test results recorded on paper can move very slowly from one level of authority to the next. When they would finally arrive at the Ministry of Health, they were too late to be of much value for either regional or central action, or for planning.

Malaria control in Brazil over the past three decades has been a two-pronged strategy: field sanitation technicians visit outlying communities, spraying insecticides, taking blood samples and treating persons suffering from malaria. Each community has a health office where people who suspect they are infected can come for an examination. The office is usually the home of an educated volunteer in the community such as a teacher, who has been trained to take blood samples and evaluate the results, which are then reported to SUCAM.

Adding the software to this equation means better control of malaria and fast epidemiological analysis, says software researcher Marcia Macedo, a post-graduate student in biomedical engineering at UFRJ. Each municipality will have a microcomputer, so SUCAM employees can enter data as it comes in from the field. The program will provide municipal SUCAM workers and central planning authorities with quick access to reliable data, presented on two-dimensional color maps and graphs.

In response to user queries, the program can provide information about incidence and location of cases of malaria in any given time period, as well as information on which of the three different types or combination thereof is prevalent in a certain region.

With later refinements, the software will provide sequential monthly maps to estimate flareups and the movement pattern of malaria using past data and variables such as geographical features, climate and demography. This way, malaria workers will be warned of possible epidemics, giving them time to begin epidemiological observation in communities in danger of an outbreak, or preemptive spraying to create a barrier to the disease's spread.

The northeastern state of Tocantins, west of Bahia and north of Goias, was chosen as the prototype of an endemic region for the system's development. Software was created using two kinds of data from this area. First, detailed geographical maps of Tocantins provided by the Ministry of Health were digitized using a computer language C (easily transferable to other computers), and entered into the program. Then data collected in the field in Tocantins from 1980-1984 was entered (a starting point for data that will later span from then up to the present), providing data such as the age and sex of the person who was infected, and the type of insect and malaria found.

The next step was to link the non-image malaria data with the images to create the program's detailed color maps, graphs and charts of malaria information.

Phase two of this project, begun in early 1993, has two main aims: first, to focus mainly on field evaluation and refinement of the system at the local health care level, and secondly to attempt to adapt the software system to a proposed malaria control project in another endemic situation, Sri Lanka, as a first step in a potentially larger network.

FIELD EVALUATION

The software has just begun a six month field test, to be carried out in Porto National, a city of 80,000 people located on the Tocantins River and comprised of separate neighborhoods with about 200 people each, which makes it manageable to study. Each set of monthly data is being examined in two ways: first, an overall analysis of all data; then a look only at less populated areas, excluding cities and large towns with higher numbers that would interfere with analysis of these smaller regions.

After the field test and evaluation are completed, improvements will be made to the software for the final - version that will be implemented in SUCAM regional offices. Then researchers will begin various epidemiological studies -- examining malaria incidence related to risk factors and demography, for instance -- to assess how the software's use has improved disease control.

ADAPTING TO OTHER SITUATIONS

While the software promises to greatly improve the ability of Brazilian health planners to deal with the high priority of curbing malaria, the UFRJ researchers are well aware of its wider application. It could be used with other diseases, as well as in any country that has the environmental and malaria data to plug in.

Many tropical countries have little or no malaria control stategy. This software aims to provide a low-cost, - simple, comprehensive way to help communities plan malaria control and prevention strategies, thus removing a serious obstacle to development. During phase two, Brazilian and Sri Lankan researchers will collaborate on ways of adapting and implementing the system in Sri Lanka.

"One of our objectives is to make the software for general applications, using geographical information systems for the control of disease epidemics," says Macedo. "We are not just trying to collect data on malaria, but are trying to create a database for use with other diseases. We plan to use geographical information systems to study the spreading of diseases here and in other countries."

GLOBAL STRATEGY FOR MALARIA CONTROL

The malaria control project in Brazil is just one of several projects supported by IDRC which address feasible and sustainable approaches to malaria control. The IDRC-supported projects reflect a renewed worldwide interest in fighting the spread of malaria.

At an international conference on malaria in the Netherlands last October, participants representing 102 member states of the World Health Organization (WHO) unanimously adopted the world declaration on the control of malaria.

The declaration is intended as a blueprint for action in the 1990s for a partnership of malaria endemic and malaria free countries.

Malaria, which for many years was at the centre of attention in the international public health community, lost its "high profile" in the 1970s and 1980s. Other diseases such as AIDS became the focus of attention. Nevertheless, the scale of the malaria problem has grown in the past two years. Its control has been complicated by an increase in the parasites resistant to medication, even to relatively new medicine such as mefloquin.

The final conference documents stated that malaria constitutes a major threat to health and blocks the path to economic development for individuals, communities and nations. Almost half of the world's population is at risk from the disease, which causes 100 million clinical cases and over 1 million deaths each year.

While over 80% of malaria cases and deaths occur in Africa, malaria is a problem in every region of the world. It affects young and old. Social, political and economic changes all contribute to the worsening malaria problem, particularly through large scale uncontrolled population movements and ecological disturbances. Environmental changes brought about by development often create conditions favourable for malaria transmission.

FOR MORE INFORMATION, CONTACT:

Prof Flavio F. Nobre
Biomedical Eng. Program
Coordanacao dos Programas de Pos-Graduacao
Universidada Federal do Rio de Janeiro
Centro de Tecnologia Bloco G,
C.P. 68501 Rio de Janeiro 219459PJ, Brazil

IDRC Reports is published weekly on-line by the International Development Research Centre.
Its aim is to keep an international readership informed about the work IDRC supports in developing countries as well as other development issues of interest.

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