Superbugs: The Killer Viruses

The thing. In the past two decades over 30 new diseases have emerged from nature to infect man. AIDS Ebola. Hanta Virus West Nile. Infectious disease kills more people than war and famine combined. The miracle of antibiotics is turning into a curse as more and more formally curable diseases become resistant to standard treatments. And in our interconnected global village the next play is only a plane ride away. The possibility of mass destruction of the human species is a 20th century

concept fostered by the Cold War and the space age. But rather than scanning the heavens for atomic bombs or wayward comets our sights should be set on things much smaller. By the time this program ends. Over fifteen hundred people will die from an infectious disease. Since the mid 1970s the world has seen the emergence of over 30 new diseases such as Ebola West Nile and hantavirus as well as the return of malaria cholera tuberculosis and other. Dangerous microbes that we could formally control are staging an unexpected comeback through the power of resistance.

Much of the ground we gained in the past 50 years with antibiotics and vaccines is being lost. In the Middle Ages deadly plagues were carried from one continent to another by ship. Today they travel by plane carried by airline passengers from one corner of the earth to another. And in a matter of hours. The two leading causes of infectious disease in man are bacteria and viruses microorganisms so small they cannot be seen with the naked eye. Bacteria are single cell plant like organisms that act more like tiny animals lacking the nourishing chlorophyll of larger plants.

Bacteria develop forms of locomotion in order to find food. Bacteria eat by consuming the individual cells of whatever they infect. Once they are sufficiently nourished they reproduce by splitting into. Bacteria are everywhere on the ground in water even floating in the air. Most bacteria are harmless or even beneficial to humans. But before the advent of antibiotics like penicillin bacterial diseases were the scourge of mankind causing deadly outbreaks like plague tuberculosis and cholera. Viruses are even more intriguing and dangerous than bacteria existing somewhere on a fine line between life and death. Viruses are neither plants nor animals much smaller than bacteria

viruses consist of partial strips of genetic code with no means of locomotion. Viruses lie dormant until they stumble upon a host to infect. A virus can infect animals plants or even bacteria by invading the host cells and commanding them to do its bidding. And the virus is unrelenting mission is always the same. To replicate unlike bacteria a virus cannot reproduce by itself. It uses the chemicals in the host cell to create replicas of itself hundreds in mere minutes. A process that usually kills the host cells. A viral infection can rarely be treated or cured. Antibiotics are useless against viruses. Our main defense is prevention.

Vaccinations give our immune systems a chance to practice fighting a weakened version of a virus before meeting the real McCoy. Once a person's immune system has successfully fought off a virus it cannot be severely infected with that exact virus again. Disease has been around long before the dawn of man. Controlling overpopulation and aging natural selection in humans. Infectious disease has influenced the course of warriors and raised entire cultures from the face of the earth. Our human history is incomplete without a testing to the power of these tiny invaders. The plague of Athens hit the same way all epidemics do suddenly and without warning. It was early summer in the year

430 B.C. and Athens was at war with Sparta. Part of Athens wartime strategy was to bring all the citizens in the outlying countryside in behind the safety of the city walls. Population and Athens swelled to half a million. A situation ripe for disease transmission. The end result was hygiene suffered and they relied heavily upon food that they imported from outside. So if a plague came in on the food supply they would catch it. And because they were concentrated inside the city the plague spread. It is thought that infected grain on a ship from Egypt brought the mysterious illness to the port of Athens within days. Hundreds of people fell ill. People who caught the disease almost always died. And it was a particularly swift and violent death. The disease progressed from the head

to the chest to the stomach to the bowels and as a result of that people dehydrated and expired. Those who came to tend to the sick caught the disease as well and also died in a seven or eight day period of time. We don't know what the what the mortality rate was but it was high enough that the Spartans who were outside the city walls were sort of mesmerized by it. They could see the funeral pyres being burned inside the city of Athens. And while the Athenians were struggling with disease inside the city walls the war outside dragged on. An incredible depression fell over the city and it worsened as the plague continued the plague hit Athens for two years and then it abated for about a year and a half and then it came back for another year. And during this whole time period it was very very depressing for the ATL

because they they looked at the world around them and hardly any other place was affected by the plague in Greece only Athens was. Organized society began to break down. They figured that if they stole from their neighbor. If they were brought up before a magistrate they would die before the court could pass sentence on them. So as a result why not live for the moment. It was the original YOU KNOW ME ME ME generation people decided that they should spend all of their money now because. In a week they may be dead. We don't have that feeling in the United States concerning diseases we basically feel that if you get a disease yes you are members of your family may die but eventually the medical community is going to come riding to our aid with some sort of pill that we can take that will cure us. He didn't feel that way. An estimated one quarter to one third of the population of Athens died from plague. And despite detailed historical records of the

event. Modern scientists still can't match the illness to any known disease. What killed the Athenians. An ancient virus long since mutated or simply in hiding. Centuries past empires crumble. New ones are built. Trade routes expand. People begin to live in crowded cities. The time is right for a new play. The bubonic plague or Black Death entered Europe in the middle of the 14th century. It started in central Asia in thirteen thirty eight. Spread first to China and India. Then followed the trade routes to Western Europe. A plague entered Europe probably in thirteen forty six by water the

Mediterranean became the great avenue of that pestilence. Traveled by ship it was carried to sleep which were carried on roads which traditionally inhabit the poles. So whenever a ship docked rats would get off the ship and infect the local population. And it spreads very rapidly. Boob onic plague is caused by the bacteria. Your scenario pestis this bacteria is passed to humans by fleas at a but not infected rat. And even if the populace had understood how plague was transmitted in the Middle Ages it was almost impossible to avoid rats. That's the European black rat that is the main carrier and that rat is fearless of human populations so it will live

very close to human beans. That is to say in your walls in your basement in your attic and Batman by and large that it was very difficult to seal in adequate houses to the entrance of the road. So part of the problem is the housing. About six days after an infected flea bite the victim would develop large Boyles known as Bilbo's and their underarms are growing fever thirst and delirium followed. By 50 to 60 percent of those infected died within a week. Particularly deadly strains of plague developed that could be passed from human to human by coughing or breathing this form of plague could kill in days or even hours. Medieval doctors and scholars came up with a host of explanations for the cause of the play. Everything from misalignment of the stars to the wrath

of God to simply bad air. And while bad air sounds a bit unscientific. It was an appealing explanation at the time. In the face of a raging disease with no treatment and no cure. Bad hair was something the population could take action against. Medieval Europeans would dispel the bad air in their homes by burning aromatic herbs outside they carried scented cloth or flower petals to be pressed against the nose for emergency protection. A popular children's song of the day has survived to modern times. The Ring Around the Rosie refers to the Red Ring of infection that surrounded the Bobo's The Posies referred to the flower petals that were carried and fall down is exactly what plague victims day. Controlling the spread of plague was impossible in Venice. Crews of

incoming ships were confined to their vessels for 40 days until it was certain they did not have the play. This is the origin of the quarantine from the Italian word meaning 40. But quarantining sailors did nothing to stop rats from disembarking in the night. Except for a few small areas. The black death struck every part of Europe. Tens of millions died in six short years. Almost one third of the population. The Black Death restructured the social system of the Middle Ages changed the fundamentals of the church and ushered in the age of the Renaissance. The date is September 1918 the end of World War One is in sight. Thousands of American soldiers are overseas fighting on European

soil. The remaining men and women work doggedly to man the factories and support the war effort. School children are saving their pennies to buy war bonds at the upcoming fourth Liberty Loan drive. Into this war ravaged world enters a tiny new enemy and influenza virus appears at Camp Devon's in Massachusetts and quickly spreads to camps in New York and Virginia. But this flu wasn't the mild sickness that had made the rounds earlier that spring. They called this virus the Spanish flu. And it was a killer. Dr Alfred Crosby is a leading historian on the 1918 flu epidemic. It hit the people in the prime of life from let's say 15 or 40 from 20 to 35.

These are the people who are supposed to be most resistant to disease and they just were mowed down by the Army the Navy particularly hard hit because of course it was staffed with people in that age group. That you think are about this epidemic this 1900 flu was one it killed so many people which is. Strange. And the other is to kill the people who should have survived. War and disease go hand in hand. Unsanitary living conditions lack of proper nutrition and fatigue lowered resistance amongst the soldiers and allowed the virus a firm foothold in military camps. All it needed was the right chance to spread to the civilian populace. Opportunity came knocking in the form of the fourth Liberty Loan parades that went

on in big cities all over the country. In October of 1918 there huge throngs of civilians and soldiers showed their patriotism bought bonds and exchanged millions of viral particles. They then got in trains cars and wagons and took the disease to their hometowns. It was in a sense the most effective dissemination of a virus ever. The Spanish Flu had hit the jackpot. If you buy it. The Spanish Flu made its way around the globe in a matter of months elevating its status from a localized epidemic to a worldwide pandemic.

In a few days or even hours a person could go from good health to near death masks became mandatory apparel. Theaters and schools closed hospitals still to overflowing. The bodies piled up faster than the undertaker's couldn't bomb them. Philadelphia is hit the hardest. Nearly 13000 died in a few short months. My youngest brother he contract it and he was the healthy one. The Spanish Flu is in 1918 and I was five years old. When Benny My brother got it. He died within three days of Simpson. The last day I remember the bedroom with Benny lying in bed and a doctor full in his hand counting the pulse and my mother beside him. And I was at the foot of the bed watching five years

although I didn't really know completely what was going on and then the doctor races he said he's gone. And my mother fainted on the spot. But there's nothing that they could have done no more than they can do today to stop it. It's like the Black Death. Understand died in the world from. That. Terrible. But. Many historians feel that 20 million is a conservative estimate. Some place the death toll as high as 50 million. The 1918 influenza McQuillan of it can happen at any time. So everybody should get their flu shot. My flu shot on Monday.

Vaccinations such as flu shots are a main defense against viruses in the 50s. A world wide vaccination program was initiated against one of history's worst killers. Smallpox The last case was reported in 1977 making smallpox the first and only virus we have managed to eradicate. Unfortunately very few viruses are good candidates for eradication. Polio is our next most likely victim. But more often than not we are the victims at the mercy of these tiny invaders. Some viruses are easier to catch than others. Some are transmitted through body fluids like HIV and influenza and others are airborne and can be inadvertently inhaled

a bite from a mosquito flea or tick can transmit viruses like malaria or encephalitis directly to the bloodstream. We are bombarded with potentially dangerous pathogens every day. Fortunately our immune systems dispelled the majority of these attacks without causing so much as a sniffle T-cells patrolled the blood and latch on to the offending virus while sending a message to the immune system to begin manufacturing the correct antibodies to combat that particular virus. The problems began when a virus slips past the immune system unrecognized and for a simple strand of genetic material viruses can be masters of disguise. Humans have creativity and ideas.

Viruses don't have creativity or ideas but they have adaptability and persistence. By that I mean that they mutate frequently. And they throw off huge swarms of new viruses which contain both the old virus and mutants so that when the viruses are placed in a situation where they can adapt they have the machinery to adapt. Animals and humans share many diseases. Waterfowl often carry viruses that don't make them sick. A mosquito bites the infected bird then infects the next creature it fights the birds act as a reservoir for the virus. The mosquitoes are the transmitters. Domestic pigs can come down with the flu. Horses and chickens are susceptible to strains of encephalitis. The horses get

sick. The chickens do not. Monkeys have their own version of AIDS. The most dangerous pathogens are those that make the jump from animals to humans. If it can then be easily passed from human to human. A new disease has emerged and the potential killer unleashed the most deadly example of this is HIV and AIDS. This virus HIV originated in monkeys and apes somewhere in Europe. Way back in history a virus jumped to humans and is now transmitted human to human to human. These species jumpers are less common but they represent the greatest threat in regard to emerging disease diseases today. HIV the virus that causes AIDS is a species jump or.

Recent studies suggest that HIV first crossed over into humans around 1930 in West Africa. Non-human primates harbor a virus similar to HIV the virus could have originally been passed on by eating meat. All receiving a bite from an infected monkey or chimp. AIDS is an insidiously slow moving disease. The virus itself will not kill its victim but the gradual weakening of the immune system allows other infections to set in. Such as pneumonia and cancer. And the fact that one can be infected with HIV and not show any outward symptoms for months even years has led to the high transmission rate. HIV can be transmitted through sexual contact intravenous drug use or blood transfusions. It can also be

transmitted from mother to child in the womb or through breast milk. The mortality rate is 100 percent. The AIDS crisis is at its worst in Africa. Over 25 million people in Africa are infected with HIV compared to only half a million in the U.S. in Botswana over 35 percent of the adult population is infected. AIDS has left millions of orphans many infected with HIV themselves it is not considered a gay man's disease in Africa. Forty seven percent of those infected are women. Dr. Luke Kinsey of CARE International has been working in Africa for 15 years.

I've been very very involved project in West Africa and East Africa. I've seen people who buy AIDS I was in often and I've seen villages being wiped out by which I mean a lot of people seem don't really know what it's about. In some areas people the same thing that sort of you know about we stuff. So if you can go and then those people that this is how it's transmitted. I would you know this is our weekend but there go some from HIV and also at the same time provide care and support for people leaving these aids. We can dream that she can make a big difference. Drugs are virtually inaccessible in Africa. The big pharmaceutical companies are not interested in giving their medicine away and the people of Africa cannot afford to buy it. We now live in a global village. There is no way we can say OK this is just up and for guy you know we need 5 8 5 away from Africa. We are all.

You know human being we only live in the same planet. Never has our lack of control over a virus been more evident than with the AIDS pandemic. HIV was brought to the U.S. on an international flight in the early 80s. A homosexual airline attendant contracted the virus overseas and unknowingly passed HIV to numerous sexual partners in several U.S. cities. Thus began the American stigma of the gay disease that hangs on to this day. And while the U.S. like other wealthy country seems to have aids under control. STEPHEN WOODS executive director of Project Open hand in Atlanta has seen some disturbing trends. In the beginning project open hand saw basically a demographic gay white middle class men who were dealing with HIV and

AIDS. And over the years and particularly in the last seven years or so we've seen a tremendous demographic shift to minority communities to African-Americans and Hispanic Americans and the common thread that we really see is that AIDS is impacting people who are dealing with poverty. And that has been the overriding concern with an organization like ours. Project Open hand has been delivering meals to people living with AIDS since 1988. It's an awareness issue for us anymore. A lot of people think that age I DNA are

no longer a big critical issue and people are no longer die from AIDS which is just not true. They're just not as visible. We don't see as many prominent people being these days. These people that we see they are hidden and their enemy government housing project in the heart of his city. Our funder generally don't go to. All these viruses and maintained in nature and just spill over into humans so most of what happens out there is because we do something. We dam up a river. We clear a forest. We go into a forest. It's not usually some mutant virus that comes running after us. These viruses may not run but they do travel migratory birds can carry

viruses across oceans and with the excess ability of global travel. Any virus is only 24 hours away. Major travel hubs and ports are often the first point of entry for a foreign virus. For example West Nile virus. This virus. In my opinion most likely came to the U.S. on an airplane in a mosquito. We have a virus it's very similar to West Nile virus called St. Louis and stuff Linus virus here. West Nile and St. Louis are both related. They both use Culex mosquitos a particular kind of mosquito to be transmitted between birds. My guess is that infected Culex pipiens mosquitoes down a nice warm place on an airplane. Maybe the toilet where it's more ice than it would be happiest. And to direct Jeff first class flight to the U.S. got out and bit some birds and started the West Nile cycle again. West Nile is an old world virus prevalent along the entire route of the Nile

in Africa. Most of the inhabitants of that region have already built up immunity and consider West Nile just another childhood disease. Migratory birds have caused occasional outbreaks in Eastern Europe but no one expected West Nile to cross the Atlantic and show up in New York. Experts predict the virus will work its way down the Eastern Seaboard before spreading west. Dr. Jonathan dey runs the Florida entomology lab and one of only five labs in the U.S. to study mosquitoes and the diseases they transmit. I think it's just a matter of time before West Nile shows up in Florida with some migrants that were worried about birds that are coming from Canada stop in New York for a

day get bitten by an infected mosquito. And those migrants will move 500 miles a day. And so the next day the weather patterns are perfect they leave Central Park and they migrate to Georgia and then settle down and then the next day or two days later they may migrate to Florida. Well the virus stays in those birds for about six days. And so any place from the time that bird is bitten by the mosquito to where it ends up six days later that bird can transmit or spread the virus anyplace along the line. The lab takes random blood samples from the local wild bird population to look for encephalitis antibodies. They also collect and test mosquito samples because West Nile and then sample ictus are in the same family. The test will also reveal the presence of the West Nile virus.

Besides relying on the capture and testing of wild birds and mosquitoes. Florida has another detection method for West Nile already in place. The Sentinel chicken program has been in operation in the state of Florida for 22 years as an early warning system for encephalitis a disease that occasionally becomes epidemic in Florida. Chickens are placed in a known Miskito habitats and are regularly tested for encephalitis antibodies. Fortunately these tests also reveal West Nile. Most of the mosquitoes that transmit these viruses like to buy birds. And in fact the natural history of these viruses is a bird mosquito cycle. It's only when a person gets in the way that they've become infected.

Chickens are used because they don't get sick when they get infected and the virus doesn't build up in their bodies so they cannot cause a mosquito to pick up the virus to infect other animals so they don't transmit the virus and they don't get sick. They do build antibody when they recover from the infection. And that's what we are detecting in this program. The presence of antibody means the chicken was recently infected and that's how we determine whether the virus is in the area or. Other states are now looking at implementing Sentinel chicken programs sent loads are being set up in a number of states along the East Coast and some a little bit further inland also in Canada. Looking for the introduction of West Nile into an area where it has not been before.

The CDC has funded a number of states to increase their Arbel virus surveillance to be on the lookout for this. The Sentinels are one part of the program although there is no stopping West Nile as it spreads across the U.S. early warning gives health officials time to alert the public and medical professionals and to increase mosquito control efforts. America has a new virus. In 1909 experts feared that another foreign virus had moved on to American soil. Reston Virginia a small town outside of Washington D.C. was home to a monkey house that reported some of its monkeys were very sick. Some of those monkeys brought a strain of Ebola virus with them from the Philippines. When the. First diagnosis was made we really thought that was

going to be all hell to pay. What we did do those do all the tests we had available and they all said it's Ebola. So we got back to the Marion and he actually had a large facility with almost 500 monkeys and these monkeys were being quarantined to be sure they didn't have any bad diseases before they were turned loose for biomedical research. It originally been captured in the Philippines. And one room had begun to die. And then another room had began to die. And then we found Ebola in another room and we decided that point that we had to take out all the monkeys. The Army investigators took care of that. They went in and they contaminated the building depopulated the you know the colony. It wasn't until later that we discovered that for the animal caretakers had been infected but it had no disease so it appeared that this was a strain of Ebola that

had a very low virulence for humans as opposed to some of the strains that kill 90 percent of the people in fact. Talk about dodging a bullet. Very very fortunate. Ebola emerged in 1976 and Zaire now called the Democratic Republic of Congo. Dr. Frederick Murphy was the first to photograph and identify this new killer. I'll never forget that moment seeing the virus in the electron microscope. The hair stood up on the back of my neck because I had nine years before worked with the virus that looked just like it and it also was a killer and that was the Marburg virus. Ebola and its sister viruses Marburg are classified a level 4 biohazard.

The most dangerous of viruses. Researchers must be sealed inside protective suits in order to conduct tests on level for pathogens. Be a bowl of virus essentially liquefies internal organs causing the victim to bleed out from every orifice. Even the pores of the skin and. Death occurs a week to 15 days from onset of the body. You don't look. So far human cases have occurred only in Africa. Outbreaks here continue but have been brought under control with improved hospital practices. Traditional burial rituals involving family members washing the body have been banned. Scientists are close to perfecting an Ebola vaccine for monkeys but a human vaccine is still years off. In the meantime Ebola lurks in the forests of East Africa. A

short plane ride away its natural reservoir still a mystery. Sometimes things happen that are new for you and you don't know how to handle. And the worse they are the more we say we pucker up and that is the pucker factor and. The biggest pucker factor that I've ever experienced I think happened in a conference room right here in CDC. We were talking about the hanta virus emergence in the southwestern U.S. one the first case of hantavirus appeared in New Mexico in 1903. The virus infects the rest of the Tory system quickly drowning the victim in his own fluids. We didn't know what it was at that time. As a matter of fact we went all around the room and nobody knew what it was and it was very clear that it was a new disease.

It was killing people. It was right here in the US. And we didn't have any idea what it was or how to control it or how many cases there would be or where it would stop. And I think without going to any exotic environment. Our travelling around the world just knowing that this was happening right here in the US was about as scary as it gets. The source of the virus was a mystery until investigators looked at the weather patterns. El Nino had brought torrential rains to New Mexico. The year before the outbreak the resulting increase in vegetation had created an explosive deer mouse population. The mice had apparently been the natural host of hantavirus for thousands of years without any known consequences to themselves or humans. But the sheer quantity of mice that year had increased the likelihood of human contact tenfold and the virus jump species. Whenever diseases appear in previously an impacted areas the possibility of foul play must be considered. Animals can be an early warning

system in the event of a bioterrorist attack. Some of the agents that would be potentially useful to a bioterrorist may also it make animals ill so it's possible that illness in animals could provide a clue to the fact that there's a risk for infection to humans. Why any unusual outbreak is subject to investigation. But some diseases raise more suspicion than others. Agents of concern to the public health officials in the context of bioterrorism are those the possibility of smallpox plague anthrax tularemia. Botulism. Viral hemorrhagic fevers those are some examples of diseases that are thought to be potential candidates for use by terrorists. Obtaining deadly pathogens is easier than circulating them.

For a bio attack to be successful. The pathogens must be widely and evenly distributed over a large populated area. A challenging task for potential terrorists. Fortunately it's not that easy to purposely disseminate microbial agents the to cause human illness. But that's not to say that it can't be done. Scientists must also be on the lookout for a new foe. Even more menacing than a potential bioterrorist attack is the very real threat of anti bacterial resistance. Resistance to antibiotics has contributed to the re-emergence of formerly controllable diseases such as malaria cholera gonorrhea and tuberculosis. Antibiotic resistance is the ability of an organism such as the tuberculosis causing organism or the AIDS causing organism to develop

defenses against the anti-viral drugs or the antibiotic drugs which are used to treat them. When this occurs the drugs can no longer cure the infection and the microbes the organisms continue to live on and on and transmit to others. Resistance flourishes wherever antibiotics are misused. Developing countries are burdened with poverty and counterfeit drugs leading to the under use of proper medication. In industrialized countries patients go to the doctor expecting a prescription a magic pill for what ails them. Doctors feel pressured to comply. A situation leading to an estimated 50 percent overprescription rate in the U.S. both over use and underused contribute to antibiotic resistance. Resistance is a genetic phenomenon which can be transmitted from one bacteria to another or from

one bacterial family to me. So what we see is that over use is selecting out resistant bacteria which can then genetically transfer resistance to other organisms. The great success of antibiotics in controlling disease has led to a slowdown in the development of new antibiotics. If resistance consumes our antibacterial arsenal there are currently no new drugs to take their place. The last major class of anti-bacterial was developed in the late 1960s. So what's happening is that slowly we are losing. The armamentarium of antibiotics which we have because of resistance. And industry is not keeping up as rapidly as we would hope in developing new ones. Antibiotic resistance threatens to render some of our most important medicines

ineffective. Global travel increases the likelihood of foreign viruses spreading to other countries. Each emerging pathogen represents the unknown a new foe that hopefully will not adapt to our biology. Infectious disease experts are busier than they've ever been but which pathogen worries them the most. What I worry most about is in a biologic resistance on the one hand and the next influenza pandemic on the other hand of the diseases that emerge and re-emerge. I would worry most about influenza. Flu is not an exciting or exotic disease but nearly everyone will contract it at some time. Complacency is influenzas greatest advantage.

Influenza is often treated as just a nuisance disease. That's partly because we are rather careless about the way we use the term flu and we apply it to stomach upsets to cold stuff and so on. Influenza is the unrivalled quick change artist of the viral world. Not only humans but horses pigs and birds are all susceptible to flu. This plethora of hosts gives the influenza virus virtually unlimited mutation capability. Because humans have a lot of direct contact with these domestic animals. Those viruses occasionally can be transmitted to humans and if there's no antibody in the population and if the virus is easily transmitted from person to person. A new pandemic can begin and it can spread rapidly around the world. Highly contagious influenza can be contracted simply by breathing new treatments promised to shorten the duration of the illness. But there is no cure.

The best remedy for a flu is prevention. Yearly vaccines can greatly reduce the risk of contracting influenza. Every year in February the World Health Organization releases the recipe for that year's influenza vaccine. Based on the results of global flu surveillance. The vaccine contains the strains most likely to circulate that year. Pharmaceutical companies scramble to begin production based on the new formula they will need to ship their vaccine in six months before flu season begins. Flu vaccine is cultivated in chicken eggs. The eggs are inoculated with the proper strains of influenza. After an incubation period. The viruses are harvested and rendered inactive.

These killed viruses are used to create the vaccine. Flu shots generally become available in October or November of each year and have become more effective over the past decade due to improve global surveillance. But even vaccines may be no help in the face of a worldwide pandemic. We would be in a race against time to get as much influence a vaccine against the new pandemic strain manufactured and distributed as possible and we would really have to work extremely hard in order to get vaccine available in time to mitigate the spread of influenza. So we really don't believe we can stop a pandemic. The yearly epidemic strains of influenza don't involve animals. Mutations occur in the virus as it is transmitted from human to human.

Eventually the virus has changed enough that the immune system does not recognize it. The strains that cause yearly flu epidemics are very different from a deadly pandemic strain. During a pandemic what we believe occurs is that the viruses that are resident in the animal populations that is in pigs or in domestic birds get transmitted to humans and if they successfully make that host species leap. And. Those viruses that can be transmitted to other humans and so on and so forth. Pandemic strains are much more lethal to humans. Flu experts are on constant lookout for strains that jump species. The outbreak in Hong Kong in 1997 put the flu world on full alert.

This was a virus that had not been shown to infect humans before. So our first thought was. My goodness we really need to make sure that this was a true human infection and not simply lab contamination because if it were a human infection then it would be extremely worried. It was a human infection. A three year old boy died of complications from a strain of flu only known to infect birds. Several other cases soon followed. It wasn't really possible to determine precisely how those people got infected but all of them. Had been to or the majority of them had been to live bird markets or had some contact with with like birds like domestic birds. Live bird markets are common in the Orient. The Hong Kong government knew in order to contain the outbreak they would have to slaughter every chicken.

Over one million chickens were euthanized. And the pandemic was halted. I think that the slaughter of the chickens certainly eradicated the source of the virus and most likely saved us from the pandemic. Every hour an estimated fifteen hundred people worldwide die from infectious diseases. The reasons for these deaths and for the emergence of drug resistance are the same. We do not use our medicines wisely or widely. Political borders offer no filter to these pathogens. Treating our own does not protect us from the reintroduction of resistant strains or microbes from foreign lands. We live in a global village and there are many many reminders of the fact that we cannot ignore infectious disease problems in other parts of the world.

We were fortunate that the bird flu in Hong Kong in 1997 did not turn out to be the beginning of the next influenza pandemic but it could have been. And in the modern age it wouldn't take very long for a virus causing to respire Torii disease in Hong Kong to appear in Los Angeles or or New York City's highly developed countries industrialized countries must become aware that infectious disease in any part of the world is a problem anywhere else. This is very important in days when airline travel permits people to go from one continent to another within a matter of hours because infections are transmitted with those people. They're also transmitted in vectors such as mosquitoes which can hitchhike. A ride on an airplane and get off at the other end so globalization has caused a great mixing of populations a great mixing of infections and so no place in the world is free of the threat of infectious diseases. One of the things about microbes and viruses is that

they can mutate faster to cause cause us trouble that we can mutate to resistance. We have to use every. Aspect of our intelligence and our public will to deal with the infections as they occur. One of the big issues. Well why is poverty. I don't know how technology can sidestep the effects of poverty. People who need clean water good nutrition and what housing. If we can't get these things I don't think there's any amount of technology that will help keep. These emerging diseases in check where they are. Over 30 new diseases have emerged in the past 20 years and no one knows what pathogenic threats await us in the future. We are the first generation ever to have the means of protecting the

world from the most deadly and common infectious diseases. But antibacterial resistance has put an advantage firmly in the corner of the pathogens. If we don't defeat our microbial foes now the battle grounds could potentially be redrawn. A.