Contents - Akademi Sains Malaysia

Climate Change — Environment andInfectious DiseasesC.P. RamachandranSenior Fellow Academy of Sciences Malaysia and President Malaysian Scientific Association(e-mail: ramacp@hotmail.com)CommentaryThe desire for healthier and better world in which to live our lives, and raise our children is common to all people andall generations. As we enter the 21st century, our past achievements and technological advances make us more optimisticabout our future than perhaps at any stage in recent history.More than 100 million people will die and global economic growth will be cut by 3.2% of gross domestic product(GDP) by 2030 if the world fails to tackle climate change, a report commissioned by 20 governments said recently. Asglobal average temperatures rise due to greenhouse gas emissions, the effects on the planet, such as melting ice caps,extreme weather, drought and rising sea levels, will threaten populations and livelihoods, said the report conducted by thehumanitarian organization Dara.It is calculated that five million deaths occur each year from air pollution, hunger and diseases as a result of climatechange that toll would likely rise to six million a year by 2030 if current patterns of fossil fuel usage continues. More than90% of those deaths will occur in developing countries, said the report. The report was commissioned by the ClimateVulnerable Forum, a partnership of 20 developing countries threatened by the climate change.Temperatures have already risen by 0.8ºC above pre-industrial times. The world’s poorest nations are the most vulnerableas they face increased risk of drought, water shortages, crop failure, poverty and disease. On average, they could see a 11%loss in GDP by 2030 due to climate change, the report said.Many efforts have undertaken to bring health issues more into focus in climate change discussions. Evidence baseddiscussions of climate change on health has been positively expanding in the past few years. This has allowed a greaterunderstanding to both governments and the general public on the relationships between changes in climate and how it willaffect specific areas. Yet much more work needs to be done, especially in understanding local scenarios.Infectious tropical diseases are still the world’s biggest killer of children and young adults. For those living in developingcountries, among the poorest of the poor no matter what their age, the risk of death and disability is always many timeshigher than those living in the developed world. Over 500 million people on earth, that is one living person in ten, sufferfrom one or more of the major infectious tropical diseases. While health globally has steadily improved over the years,on the other hand many people living in poorer countries have seen little, if any, improvements at all. The gaps betweenthe health status of rich and poor are at least as wide as they are half a century ago, and are becoming wider still. Despitethis, the most important pattern of progress now emerging globally is an unmistakable trend towards healthier, longer life.In recent years we have all been affected by the increased spread of infectious diseases, be it SARS, swine flu, bird flu,H1N1, Nipah virus, dengue or monkey malaria. As humans dominate more of the world we become an even larger targetfor these and other diseases. A rise in the incidence of new and previously suppressed infectious diseases is being linked byscientists with dramatic climatic and environmental changes now sweeping our planet Earth. Deforestation, destruction ofnatural habitats for agriculture, road and irrigation, pollution of rivers and coastal waters, are promoting conditions for newand old pathogens to thrive along with urban sprawl, lack of sanitation and creation of slum conditions.A case in point is the highly pathogenic Nipah virus in Malaysia was found in the Asian fruit bats. In the late 1990s itemerged as a fatal disease in humans. This has been linked with a combination of forest fires in Sumatra and the clearanceof natural forests in Malaysia and Indonesia for palm oil plantations. Bats, searching for fruits were forced into closercontact with domestic pigs giving the virus its chance to spread to humans via people handling pigs. Almost similar butecologically different situation was reported later from Bangladesh with Nipah virus infections. Anoher example also fromMalaysia was the transmission of monkey malaria Plasmodium knowlesi to human in Kapit in the state of Sarawak. Theissue of environmental degradation and a rise of many new and old infectious diseases is a complex, sometims subtle,one that is causing increasing concern among scientists and public health specialists. Overall, it seems intact habitats andlandscapes tend to keep infectious agents in check, whereas damaged, altered and degraded environment shifts the naturalbalance thereby triggering the spread to people of new and existing diseases. Environmental distruption and change, and thepoor handling of human and animal wastes are also to blame. International travel, technological change and globalizationof trade in agriculture and other products favours the spread of diseases.74