SARSIs this a glimpse of the future?By Gary F. Arnet, D.D.S. |
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Website Exclusive • March, 2003 |
Severe Acute Respiratory Syndrome, SARS, is a new respiratory disease that has recently infected people in Asia, Europe, and North America. The emergence of this disease brings up questions both about this disease, as well as the possibility of other worldwide infectious diseases. Whether a naturally occurring deadly flu or a terrorist biological attack, many of the steps that health officials and you can take are the same.
The first reported case of an unusual pneumonia, now known as SARS, was reported in Guangdong province in southern China on November 16, 2002. In February and March 2003, unusual outbreaks of this disease were reported in Hanoi, Vietnam and Hong Kong.
On March 12, 2003, the World Health Organization (WHO) issued a rare global alert about this new infectious disease of unknown origin, followed by an emergency travel advisory for international travelers, healthcare workers, and public health authorities.
This is a rapidly emerging disease and there are still many questions about the disease and how it will spread. Experts are learning more on a daily basis and many of the questions will be better understood by the time this is published.
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SARS is a flu-like viral illness that begins with a fever of over 100.4 degrees F (38 degrees C) and is often associated with chills, headache, and body aches. Initially, mild respiratory symptoms may be present. Within two to seven days individuals develop a serious pneumonia characterized by a dry, nonproductive cough that may become so severe that they cannot breath. In about 10% to 20% of the cases, patients with SARS need to be placed on ventilators to breath.
In April 2003, it was definitely established that SARS is due to a virus never seen before in humans. It is a type of coronavirus, so-called because of a halo or crown-like (corona) appearance when viewed under microscope. Viruses in this group also cause the common cold in humans and respiratory, gastrointestinal, liver, and neurological diseases in animals. Scientists suspect that this new human virus is a cross-species transmission from an animal virus which has mutated to infect humans.
At this time it appears that the SARS virus is spread by droplet transmission. When someone ill with SARS coughs or sneezes, droplets containing the virus get into the air and are breathed in by another person. Droplets can also contaminate surface areas such as counters, handrails, and door handles. Individuals touching these surfaces can catch the disease. It is known that other coronaviruses can survive on such surfaces for as long as three hours.
Infected individuals are most infectious when they have symptoms, such as a fever or a cough. It is not known how long before or after symptoms develop that they can spread the disease. Most individuals who have contracted SARS have had direct and close contact with an infected individual, such as a family member or health care worker. The incubation period from the time of exposure until the onset of symptoms ranges from two to seven days, although occasionally it has taken 10 days.
Victims of SARS in the United States and most of the world have been individuals who have traveled to Asia or have been health care workers who did not use effective infection control measures when treating SARS patients. To date, it has not spread into the general community of these areas.
In Asia, however, it has spread into the general community. WHO investigative teams in Guangdong province have evidence that some infected individuals are “super spreaders” capable of infecting as many as 100 other individuals.
As of this writing SARS has occurred in 27 countries, China, Taiwan, Vietnam, Canada, Singapore, and the United States having the most number of victims. Mainland China and Hong Kong account for 90% of the reported cases.
It was initially reported that 5% of patients with SARS died, but recent reports from China and Singapore indicate the death rate could be as high as 10% making this a very serious disease should it spread worldwide.
Statistics are not always accurate with a fast moving disease, however. The way SARS is diagnosed is still being refined and there has been intentional underreporting of the disease.
On April 19, the Untied States reported 220 cases with 12 deaths. By April 22, this had been downgraded to 38 cases and no deaths as CDC officials adopted a stricter definition of SARS. Of these, 33 had traveled to infected areas of Asia.
It is not really known how severe the SARS problem is in China. Leaders initially tried to hide the outbreak of the disease and then actually moved patients out of hospitals so that WHO doctors would not see them.
Cases of SARS have spread from the Guangdong province in the south to Inner Mongolia in the north and Zhejiang province in the east. Health experts are worried the disease will spread rapidly in the countryside where 70% of China’s 1.3 billion people live.
Health care in these regions is poor and the WHO representative in China, Henk Bekedam, warns of the possibility of large outbreaks in areas that do not have the resources to manage the disease. Even Chinese Prime Minister Wen Jiabao warned that the health care system was not adequate and the disease could spread with consequences “too dreadful to contemplate.”
Currently, to be considered to have SARS an individual must have pneumonia or acute respiratory distress syndrome in addition to a fever and travel within 10 days to an infected region of the world or recent contact with an individual known to have SARS.
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There is no rapid blood test for SARS at this time, although there should be shortly. German biotechnology company, Artus, reports they have a test they are going to distribute for free that can confirm the presence of SARS in two hours, rather than the 10 days currently required. When a test becomes available, doctors will be able to determine immediately whether a patient has SARS or a different respiratory ailment.
No vaccine is yet available to prevent SARS since the disease is so new. CDC scientists have asked over a dozen American and European healthcare companies to help find such a vaccine, which will take months or years to develop.
Since there is no cure for SARS, the medical treatment is supportive. Fever is controlled with medicine and fluids are given to prevent dehydration. If a patient develops severe breathing difficulty they are given oxygen, and placed on a ventilator, if necessary. Since SARS is caused by a virus, antibiotics are not effective.
Pandemics
A pandemic is an epidemic that occurs worldwide. SARS is the latest in a string of pandemics that have started in southern China. The high density of humans living in close proximity with ducks, chickens, and pigs in this area allows for viruses from these animals to mutate and spread to humans.
Every year, flu viruses originating in China spread worldwide. Most of the time these are minor genetic changes to existing flu viruses to which the human immune system rapidly adapts. Every so often, however, an entirely new strain of virus originates from a virus of a different species.
The CDC reports that on average 10% to 20% of residents in the United States get the flu every year and 36,000 die. While this is a huge number of people who die from the “regular” flu, many who die are elderly or have health problems.
Why does SARS seem to have public health officials worried more than the flu? Partially, it is because SARS is a new disease and they don’t really know what to expect. Also, it appears from cases in Hong Kong that SARS patients have a death rate much higher than that of other types of flu or pneumonia. Younger and healthier individuals are dying from SARS than from a normal flu. A major outbreak could easily overwhelm hospitals and intensive care units.
Three or four times a century, a large pandemic of flu spreads worldwide from its start in southern China. In 1918, the Spanish flu spread rapidly throughout the world. Although the death rate was only 2% (much less than SARS), within one year somewhere between 20 and 40 million people died worldwide in what was the most deadly pandemic in the history of the world. Some researchers think the number of deaths was actually closer to 100 million, with 20 million in India alone.
It is estimated the Spanish flu killed one out of every sixty people in the entire world (as many as 40 million). More Allied and German troops on the front lines died from the flu than from combat. The number of deaths surpassed the Russian flu of 1889, which killed 250,000, and even the Black Death of the Middle Ages.
In 1997, the world was threatened with another flu that health officials worried might be as deadly as the Spanish flu. Hong Kong “bird flu” was a completely new strain of virus that was part human virus and part bird virus and one that should never have infected humans. Like the Spanish flu, many of the deaths were in teenagers and young adults, rather than the elderly and those with medical problems. It had the potential to be a disaster for the world.
Researchers determined it was a virus in chickens that could be transferred to humans. Health officials ordered all of the 1.2 million chickens on Hong Kong Island and Kowloon Island be killed to prevent spread of the disease and the disease was stopped before it could travel worldwide.
This was a warning for those who had forgotten how devastating influenza or other worldwide infectious diseases can be. Public health officials today remember, and are dealing with SARS to prevent worldwide disaster.
To stop the spread of the disease worldwide, doctors and health care workers try to create a “ring” around the disease to contain it in a geographic area. If the disease can be contained in an area, the disease will stop as infected individuals get better or die.
This method seems to be working. In Singapore, a major transportation hub of Asia and one of the cities hard hit by SARS, local health officials took rapid and aggressive action.
More than 2,500 individuals who had close contact with SARS patients were quarantined to their homes under threat of large fines. All travelers into the city were screened medically and all schools were closed. When an individual came down with SARS, they were taken to a hospital and a team of 100 “contact tracers” tracked down anyone who could have been in contact with them. This included not only family and friends, but neighbors, co-workers, and food vendors. All of these individuals were quarantined at home.
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As a result of public health efforts, SARS is on the decrease in Singapore. Similarly, Vietnam has had no new cases after infection control methods were instituted.
In contrast, in Hong Kong officials kept the SARS pandemic hidden from the media in order not to frighten citizens or decrease tourism. As a result, Hong Kong had more cases of SARS than any other city and, at one point, had almost as many people hospitalized with SARS as the rest of the world combined. Officials have now closed schools and taken infection control seriously. In Beijing, where cases were initially hidden, over 4,000 people have been quarantined.
Should you be worried?
Clearly, health organizations throughout the world are worried; however it is hard to guess at the outcome of SARS.
At present, it seems that it is a minor problem for most of the world, one that can be contained through proper public health and infection control techniques. Limiting international travel to Asia and close monitoring or quarantine of those individuals who travel there may be necessary. The disease could be essentially gone within weeks in most of the world.
This could change, however, if infected individuals refuse voluntary quarantine and spread the disease into the general population. In such cases, mandatory quarantines may have to be instituted. President Bush has already signed Executive Order 13295 that added SARS to the list of diseases for which a person can be quarantined.
Eradicating SARS from China may also be a problem. Poor health care and large population densities make it likely the disease will spread, possibly rapidly and widely as the Chinese prime minister warned. We should know by the time this is published.
It is clear that infectious diseases are a threat to our society. Whether naturally occurring or a deliberate epidemic (WHO’s term for a terrorist biological attack), pandemics have occurred throughout the history of mankind and will continue. Frequent international travel will insure that a disease in one location will rapidly spread throughout the world.
This time, world health care providers and public health experts worked with unprecedented cooperation after the SARS pandemic began. They fairly rapidly identified this new strain of virus and shared information on treatment. Many nations and the WHO already had existing plans for a biological terrorist attack and this was a good test of those plans.
Protecting yourself from SARS
Most of us in the United States need to do little to protect ourselves from SARS, since close face-to-face contact with an infected patient is required to catch the disease. So far, it has not spread by casual contact in the community.
However, those individuals who have had close contact with someone who has SARS or healthcare workers treating SARS patients should take precautions to avoid catching the disease themselves. The CDC recommends the following precautions be taken for at least 10 days after the fever and respiratory symptoms, such as coughing and sneezing, have subsided.
Patients with SARS should stay home and limit interactions with others outside of the home. They should not go to work, school, day care, or public areas. Before sneezing or coughing, a SARS patient should cover their mouth and nose with a tissue, which should be disposed of properly. The infected person should wear a surgical mask during contact with uninfected individuals. If they are unable to, others in the house should wear masks when in close contact with the patient.
Surgical masks or other masks that cover the nose and mouth are effective in blocking the droplets that contain the SARS virus. Healthcare workers and others in very close contact with patients having any infectious disease use special surgical masks, called N-95 respirators, which have been certified to block out infectious microorganisms.
All members of a household with a SARS patient should wash their hands frequently or use alcohol-based rubs to prevent spreading virus that may have contaminated surfaces. Disposable gloves should be used and hands immediately washed after contact with body fluids from a SARS patient.
Eating utensils, towels, and bedding should be not shared between SARS patients and other members of a household. Others may use these items after they have been washed or laundered with hot water and soap.
Members of a household with a SARS patient do not need to restrict their own outside activities unless they develop a fever or respiratory symptoms. If they do, they should immediately seek medical care.
In Asian countries hit hard by the disease, people are taking additional precautions. Many wear masks when in public, avoid touching rails or door handles, and avoid shaking hands. Churches have stopped using a common communion cup and surfaces in public places are being wiped down with disinfectant.
Travel
One of the most likely ways to get SARS is to travel to an infected area. While airline travel has spread the disease worldwide, SARS is only a concern if you are traveling to an area that has large numbers of SARS cases.
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Because of this, it is recommended that travelers avoid all nonessential trips to mainland China, Hong Kong, Singapore, Vietnam, and Toronto, Canada. This does not apply to travelers whose only contact with the country is a connecting flight at an international airport. This list will change as the disease improves or progresses worldwide, so those considering travel should check current CDC or WHO travel advisories.
International travelers departing from these countries are being screened before boarding planes. Travelers who are ill or exhibit symptoms are seen by a physician and may be asked or required to delay their trip until they are well. In many airports throughout the world, arriving passengers are also checked for fever or signs of illness. They may be quarantined for 10 days if they are ill.
The future
At this time, it is hard to know what to expect from the SARS pandemic. It appears that rapid action by public health officials throughout the world is keeping the disease contained to some regions of Asia. Whether it will become a worldwide disaster or simply stops is yet to be seen.
What we can conclude from this is that the world is still vulnerable to infectious disease, just as it has been throughout the history of man. Maybe even more. SARS is a new naturally occurring infectious disease. Other diseases will develop in the future from mutations of current diseases or by diseases spreading from one species to another, for example HIV/AIDS.
Maybe even more frightening are infectious diseases spread intentionally in the form of biological weapons by terrorists or nations. These may have devastating effects since they are designed to kill millions.
For most of us, there is not much we can do to prepare for specific infectious diseases. Stockpiling antibiotics or medicines by individuals is not advised. Besides, it would be hard to know what medicines to stock before it was known what disease would be used in an attack.
Some things can be predicted, however. Should a major outbreak of smallpox or another serious infectious disease occur, it is likely the nation and world would immediately take actions to stop transportation and travel. Involuntary quarantines would be put in place. Our nation’s infrastructure would be crippled. Just think of the effect on travel, mail, and delivery of goods caused by the shut down of air traffic following the September 11 attacks. What would happen if this also included ships, trains, trucks, and private transportation?
Individuals and families need to prepare for such possibilities by having food, water, and emergency supplies. These are the same things that they should have for natural disasters or terrorist attacks. The only things one might add to disaster kits are surgical masks since they might become scarce during a major epidemic.
The Federal Emergency Management Agency (FEMA) and Department of Homeland Security recommend everyone have a 72-hour supply of emergency items. A quarantine or closure of national transportation could easily last several weeks, so it would be wise to have far more than a 72-hour supply of food and water.
While it is still to be seen what will happen with the SARS outbreak, there is no question that we all need to prepare now to deal with major outbreaks of infectious disease or biological terrorism in the future.