Environmental Problems, Their Causes, and Sustainability 1

SolutionsIncrease research on tropicaldiseases and vaccinesReduce povertyDecrease malnutritionInfectious DiseasesImprove drinking water qualityReduce unnecessary use ofantibioticsEducate people to take all of anantibiotic prescriptionReduce antibiotic use to promotelivestock growthCareful hand washing by allmedical personnelImmunize children against majorviral diseasesOral rehydration for diarrheavictimsGlobal campaign to reduceHIV/AIDSFigure 19-15 Solutions: ways to prevent or reduce the incidenceof infectious diseases, especially in developingcountries. Which two of these solutions do you believe are themost important?An important breakthrough has been the developmentof simple oral rehydration therapy to help prevent deathfrom dehydration for victims of diarrheal diseases,which cause about one-fourth of all deaths of childrenunder age 5. It involves administering a simple solutionof boiled water, salt, and sugar or rice, at a cost ofonly a few cents per person. It has been the major factorin reducing the annual number of deaths from diarrheafrom 4.6 million in 1980 to 1.9 million in 2002.Few investments have saved so many lives at such alow cost.In 2001, the WHO began promoting a do-it-yourselftechnique that uses sunlight to disinfect water. Theprocess is simple: fill a transparent plastic bottle withcontaminated water and lay it horizontally on a flatblack surface (which absorbs more heat and kills morepathogens than a lighter surface can) in the sunlight.After several hours, the heat and ultraviolet rays of thesun kill most illness-causing microorganisms in pollutedwater. This simple method is especially useful intropical countries where there is intense sunlight.How Serious Is the Threat of Bioterrorism?A Growing ConcernBioterrorism that involves releasing infectiousorganisms into the air, water supply, or food supplyis a serious and growing threat.One of the threats in our increasingly interconnectedglobal society is bioterrorism. It involves the deliberaterelease of disease-causing bacteria or viruses into theair, water supply, or food supply of concentrated urbanpopulations.According to antiterrorism experts, bioterrorism isa much easier, cheaper, and more effective way to causeillness, death, and mass terror and chaos than crashingplanes into buildings or setting off dirty nuclearweapons. The materials and tools to make biologicalweapons are inexpensive and easy to get. A state-of-theart laboratory for making biological warfare agents requiresabout $10,000 of off-the shelf equipment such asa beer fermenter, a protein-based culture of the diseaseto be produced, protective plastic clothing, and a gasmask. The lab could be housed in a space about the sizeof a small bathroom. Now that the sequencing of thegenome of the flu virus is nearly complete, bioterroistscan develop more lethal flu viruses and easily transmitthem through the air in tiny droplets.Since the end of World War II, the United Statesand the former Soviet Union both have spent billionsof dollars developing, producing, and stockpilinglarge quantities of biological weapons of mass destruction.Figure 19-16 provides information about some ofthe common bacterial and viral agents these countrieshave studied and developed.Both countries have used recombinant DNA techniquesto produce more dangerous versions of theseorganisms that act faster, are more virulent, and are resistantto antibiotics used to treat them. They have alsocreated new and even more dangerous infectious organismswith properties that are classified as top secret.Both countries have promised to destroy their biologicalweapons. But because of the secrecy of theseprograms there is no way to know how many weaponsremain.Thousands of former Soviet scientists with knowledgeabout how to develop these weapons are living inpoverty. There is fear that countries interested in developingbiological weapons will hire some of them. In1995, the U.S. Central Intelligence Agency (CIA) identified16 nations suspected of having programs to developand stockpile biological warfare agents. In addition,thousands of molecular biologists and graduate-schoolstudents around the world have enough knowledgeabout recombinant DNA and cloning technology to designand mass produce biological warfare agents.Once made, the bacteria or viruses can be carried ina small vial or aerosol container not detectable by conventionalsecurity equipment. They could be released426 CHAPTER 19 Risk, Toxicology, and Human Health