Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: SUNDAY, April 16, 1995 TAG: 9504180024
SECTION: HORIZON PAGE: HORIZON EDITION: METRO
SOURCE: ROBERT S. BOYD/KNIGHT-RIDDER NEWSPAPERS
DATELINE: LENGTH: Long
No wonder people worry about what's going on down there in the invisible world of viruses, bacteria and one-celled creatures with an attitude.
Scientists say the danger of infectious diseases is deadly serious - not just Hollywood hype.
Old ailments that people thought had been vanquished, like whooping cough and tuberculosis, are making a comeback, often in virulent new forms that resist previously successful medicines.
Joining them are previously unknown plagues, like the terrifying Ebola virus featured in ``The Hot Zone,'' or the hantavirus that broke out in New Mexico in 1993 and spread to 15 states, killing at least 25 people.
There have been at least 11 lethal outbreaks of emerging - or re-emerging - diseases around the world since 1990. An intestinal parasite, cryptosporidium, felled 403,000 people in Milwaukee in 1993, the largest attack of waterborne illness in U.S. history. Russia suffered 50,000 deaths last year from diphtheria, a disease that had supposedly been conquered.
At a panel on infectious diseases at the National Academy of Sciences in Washington recently, Joshua Lederberg, a Nobel Prize-winning biologist, likened the situation to a race for survival between humans and microbes.
``The question is, will we get them before the bugs get us?'' Lederberg said. ``We're beginning to lose ground.''
Five major U.S. government reports have warned about the peril in increasingly stark terms over the last six years, but scientists say the nation - and the world - remain woefully unprepared.
The White House is planning a conference in Washington this summer to plot a course of action.
The World Health Organization, based in Geneva is also taking up arms, since infections still kill more people worldwide than anything else, including heart disease or cancer, the leading causes of death in the United States.
``Microbes are our major contestants for survival on the globe,'' said biologist Richard Krause, a senior adviser to the National Institutes of Health. ``They were here 2 billion years before us, and they'll be here long after we're gone.''
The recent blossoming of dangerous infections is startling because it comes after decades of complacency. Since World War II, people in advanced nations, including most doctors and scientists, believed that modern drugs and vaccines had given mankind the upper hand over microorganisms.
``Starting in the 1950s, it was thought infectious disease was no longer a problem, and we could move on to heart disease and cancer,'' said Krause. ``It was utter nonsense!''
In 1969, Surgeon General W.H. Stewart said it was time to ``close the book on infectious diseases.''
But now maladies that used to afflict only poor, tropical countries leap across oceans and time zones to enter the United States. AIDS, today's equivalent of a medieval plague, began with a monkey in Africa, jumped to North America and is now infecting Asia on a massive scale. Malaria, which causes a million deaths a year, has returned to Florida and Southern California.
In 1991, an ancient killer, cholera, traveled across the Pacific and surfaced in the Western Hemisphere for the first time in a century. Within two years at least 900,000 cases were detected in South and Central America. More than 8,000 people died. Recently cholera bacteria have been detected off U.S. shores in the Gulf of Mexico.
``The microbe that felled one child in a distant continent yesterday can reach yours today and seed a global pandemic tomorrow,'' Lederberg said.
Emerging diseases have become enough of a concern that the Centers for Disease Control, U.S. Health Department, has set up monitoring centers in four states, Oregon, California, Connecticut and Minnesota. The centers hope to accumulate information that will make it possible to warn doctors when a disease is about to strike.
The Emerging Infections Programs aren't just looking at infections, however. Their concerns range from food-borne illnesses and super bacteria to a strain of meningitis that has crept into Oregon by way of Norway, Spain, Cuba and Brazil.
Oregon health officials believe the new meningitis, called the B strain, has caused its deaths from meningitis to double from 22 in 1991 to 56 in 1994. California's focus is on Valley Fever, caused by a fungus in the soil. People who breathe the tainted dust become ill with a mild flu-like symptoms to severe pneumonia.
Connecticut is analyzing risk factors for Erhlichia, a bacteria often confused with Rocky Mountain spotted fever and that infects blood cells and can cause anything from mild flu to death. Research in Connecticut is on ways to prevent infections from cryptosporidium, the water parasite that infected Milwaukee in 1993.
The monitoring programs are being phased in with $6.7 million the CDC got in fiscal 1995.
Scientists cite several reasons for the alarming resurgence of infectious diseases:
nPopulation growth has jammed millions of desperately poor people in crowded cities with little or no sanitation, an ideal breeding ground for malaria, yellow fever and cholera.
nLoose sexual behavior and intravenous drug use have transformed AIDS from an isolated African problem into a worldwide curse.
nThe loss of forests drives disease-carrying animals and insects into contact with people. The growth of suburbs in wooded areas frequented by deer and ticks spread Lyme disease throughout the Northeastern United States.
nJet-age travel whisks germs around the world. A ship bearing the cholera virus in its bilge water infected shellfish in Peru; later an aircraft ferried a dozen sick people from Lima to the Los Angeles airport.
nBacteria develop new strains that are resistant to antibiotics. Jim Henson, the Muppets puppeteer, died in 1990 of a highly toxic, mutant variety of streptococcus that penicillin could not control.
nAfter 40 years slathering ourselves with penicillin, erythromycin and other wonder drugs, we humans have lost much of our natural immunity. For example, the resistance to influenza left by the terrible epidemic that killed half a million Americans in 1918-19 has almost vanished.
``We're more vulnerable today than we were in 1918,'' said Lederberg. ``I can confidently say it will happen again.''
nGlobal warming - if and when it occurs - would accelerate infectious disease. On land, heat and humidity foster germ-carriers, like mosquitoes, that spread malaria and yellow fever. In the ocean, higher temperatures cause enormous blooms of algae and plankton - so-called ``red tides'' - that harbor the cholera bacteria.
Stephen Morse, a leading disease researcher at Rockefeller University in New York, attributed the 1993 outbreak of hantavirus in the American Southwest in part to El Nino, a huge pool of warm water in the South Pacific that affects the climate thousands of miles away.
``An unusually mild and wet winter and spring led to an increased rodent population and thus to greater opportunities for people to come in contact with infected rodents and hence with the virus,'' Morse wrote in the inaugural issue of Emerging Infectious Diseases, a new government journal.
The White House conference this summer will be the first to focus specifically on the connection between global warming and human health, according to Robert Watson, the presidential aide in charge of arranging it.
``This has been a fairly invisible issue so far, and we need to elevate it,'' Watson said. ``Climate change has many implications for human health.''
The timing and rate of global warming is controversial, Watson said. But the conference is an attempt to prepare for what might happen if the world gets 2 to 8 degrees warmer over the next century, as many scientists predict.
Rita Colwell, a University of Maryland microbiologist, said ``a very small change in temperature can have a very big effect'' on the spread of disease.
Colwell, who is also president of the American Association for the Advancement of Science, has written many papers showing how warmer water stimulates algae in which cholera bacteria lurk, later to infect people who drink or bathe in the water or eat shellfish.
Despite the multiple warnings, public health officials and scientists say the United States, as well as the underdeveloped world, is poorly prepared to respond to a major outbreak of infectious disease.
The Institute of Medicine, a branch of the National Academy of Sciences, declared that adequate detection and reporting systems are lacking; there is a shortage of trained researchers and public health specialists; effective vaccines and drugs are often unavailable. Despite the growing threat, not one new antibiotic was put on the market in 1994, Lederberg said.
Last year, the Centers for Disease Control and Prevention, a branch of the Public Health Service, urged that the United States organize an international surveillance system against infectious disease - ``like radar or the early warning systems that detect threats to national security.''
Unless such precautions are taken, the world is on the verge of a ``medical disaster,'' a Rockefeller University biologist, Alexander Tomasz, told the American Association for the Advancement of Science.
Staff writer Sandra Brown Kelly contributed information to this story.
SOME EMERGING OR RE-EMERGING INFECTIOUS DISEASES
DISEASE ................ OURCE...............1993 cases
U.S.........Va.
(Bacteria)
Cholera .................contaminated water..................18*
E. coli ................ undercooked beef, raw milk
Legionnaires disease ... bacteria in water, air-cond.........1,280.......11
Lyme disease ........... tick bites......................... 8,257.......95
Group A Streptococcal....loss of immunity to bacteria*
Tuberculosis ........... loss of immunity to bacteria........25,313......458
(Viruses)
Dengue fever ........... mosquito bite
Ebola virus ............ infected blood
Encephalitis ........... mosquito bite...................919........44
Hantavirus ............. rodent urine and feces..........91.........1*
Hepatitis B .............unprotected sex, drug needles...13,361.....157
HIV/AIDS ............... unprotected sex, drug needles...103,691...,625
Influenza .............. airborne virus
Yellow fever ........... mosquito bite
(Parasites)
Cryptosporidium ........ parasite in water*
Malaria ................ mosquito bite...................1,411........41
Cholera: Epidemics caused by a new pathogen, Vibrio cholerae 0139, occurred in late 1992 and early 1993 in southern Asia; first case in the United States also in 1993 and was California resident who had visited India that year
Group A streptococcal invasive type: In 1994 was linked to 11 deaths in Britain, two in South Wales, three in Illinois, and in 1995, 11 cases were identified in Virginia
Malaria: In August '93 in New York City, three people who had not traveled were diagnosed with malaria
Hantavirus: Statistics for '93-August '94 and include Australian hiker who was exposed to hantavirus while walking Appalachian Trail through Giles County, Va.
Cryptosporidiosis: In spring 1993, because of a contaminated municipal water supply in Milwaukee, Wis., 400,000 people became ill and 4,400 required hospitalization
Sources: Institute of Medicine, Centers for Disease Control
by CNB