SARS

Severe Acute Respiratory Syndrome (SARS) toc By reaching up, touching the shiny bar which lines the top of the subway car, a woman contracted a disease she had no idea surrounded her daily commute to work. It was November 2002 and a new disease was sweeping the bustling city of Hong Kong and the surrounding Guangdong Province. Severe acute respiratory syndrome (SARS), a new form of coronavirus, was sickening the population of Southeastern China. The origin was unknown. Although scientists were scrambling to find some semblance of cure or prevention, the strain of coronavirus was still fairly unknown. The World Health Organization was not informed of the outbreak until February 2003, so China was left to fight the virus with its own resources for 3 months.

Hong Kong has a population of 7.1 million people with a population density of 16,576/sq mi. It has the 4th largest population density of sovereign states, after Macau, Monaco and Singapore. The climate in Southeastern China is warm all year round, with yearly lows at around 60˚F and highs of 88˚F. Guangdong Province is the most populous province in China, after Sichuan and Henan. The province has 79 million permanent residents. It is one of the areas with the greatest economic success in China whose country equivalent in GDP is the Netherlands. Guangdong Province and Hong Kong are both located on the South Sea, making both areas important ports for China's trade between other Asian, African and North/South American countries.



SARS was one of the first outbreaks/viruses discovered by online surveillance methods. Canada was the first country whose Global Health Intelligence Network tracked a series of news reports that detailed a flu outbreak. The WHO then contacted the Chinese government and did not get confirmation of an outbreak until February of 2003.

The map above details the dissemination of the virus by means of trade and travel. The outbreak did not catch the attention of the mass media until an American man traveling in China and flying to Singapore died in a Vietnamese hospital of these "flu-like" symptoms. The WHO soon after initiated a global alert regarding pneumonia/flu like virus. The morbidity rate for SARS depends on the age of the individual affected. SARS is fatal for less than 1% for people 24 and younger, fatal for 6% of 24 to 44 year-olds, 15% of 45 to 64, and 50% of 65 or older.

=__Structure__= A coronavirus is an enveloped virus with projections from the surface of it that resembles a halo. These envelope proteins provide the virus with structure and strength. In order to survive the virus must inject itself into host cells and infect with its single strand of RNA. SARS is caused by a SARS coronavirus which has mutated to affect humans. Before the SARS coronavirus was only present in some species of animals. The single strand RNA virus, SARS coronavirus, was traced back to the small, cat-like creatures called civets cats. Civet cats are native to Asia and Africa. The SARS coronavirus can also be found in palm civets, raccoon dogs, cats and bats. Contact between humans and these animals may have accelerated the mutation process and started the outbreak in Hong Kong in 2002. Civet cats are sold in markets in Asia and often are pets. The Masked Palm Civet is allegedly the starting point of the SARS outbreak in Southeastern China. The area in Asia where Masked Palm Civets are found. =__Transmission__= As mentioned above, SARS is believed to have jumped from the masked palm civets to humans to cause the outbreak of 2002 in Southeastern China. The increasing domestication of the animals as pets has increased human contact, making it easier for the virus to mutate and jump species. Once the virus mutated to be dangerous for humans, close person to person contact with anyone infected could pass the virus. It would spread through the touching of a contaminated surface then introduction into a mucous membrane. Respiratory droplets, or infected air, could also spread the disease causing many citizens of Hong Kong to wear masks. Because much is still unknown about the development of SARS, scientists believe that there are other unknown methods of transmission. =__Symptoms and Disease Progression__= SARS has been described as a serious case of pneumonia. The symptoms are very similar to a severe cold, sometimes resulting in death. Symptoms occur between 2 to 10 days after exposure to the virus. The first symptom is usually fever then flu-like symptoms. The disease can kill if other systems of the body are compromised by the presence of the cold/pneumonia like symptoms. Heart failure, liver failure and respiratory failure can all occur in a patient with SARS, depending on their original health situation. The compromise in the immune system renders the body more susceptible to other diseases and viruses. It is common for a patient with SARS to also develop pneumonia due to the compromised immune system. The morbidity rate of SARS during the Southeastern China outbreak was recorded as 9 to 12% of the people diagnosed died. For the patients over 65, the morbidity rate was around 50%. This is because an older person may have a weaker immune system than someone young who contracted the disease. Chest X-rays of patients with SARS.
 * **Hallmark Symptoms**
 * Some of the symptoms characteristic of each case of SARS are:
 * cough
 * difficulty breathing
 * fever higher than 100.4˚F
 * **Common Symptoms**
 * Some of the symptoms common of each case of SARS are:
 * chills/shaking
 * coughing
 * fever
 * myalgias
 * cephalgias
 * **Less Common Symptoms**
 * Some of the symptoms common to only a few cases of SARS are:
 * cough that produces sputum (phlegm)
 * diarrhea
 * nausea/vomiting
 * runny nose (associated with cold)
 * sore throat
 * Disease Progression**

=__Pathogenesis__= A virus cannot survive for long on its own, so it needs to find a host cell to introduce its genetic information to. The SARS coronavirus, similar to other viruses, attaches to a host cell's cytoplasm and uses endocytosis to move into the cell. The virus is uncoated of its envelope proteins and the viral RNA is introduced into the cell. The SARS coronavirus has adapted to create a cap which covers the end of the RNA that resembles the cap on the end of a host cell's RNA, disguising the invader RNA. The viral RNA has been genetically modified to resemble the host RNA. Then the ribosomes attach to the RNA and viral proteins are produced. The host cell will then use these proteins in the mechanisms of the cell and alters the processes of transcription and translation. The production of viral proteins then interferes with the host cells processes of synthesis of the cytoskeleton, inflammation and apoptosis. After the host cell incorporates the viral proteins into its functions, the cells are compromised and damage is done to the host cells. This damage is often in the pulmonary tissue of the victim, resulting in the cold like symptoms. The proteins are likely to be inducers of apoptosis, killing host tissue and cells. The presence of the virus in the immune system can inspire a cytokine storm in the communication process between immune cells and cytokines. The attempts of the cytokines to inform other cells of invaders can sometimes be over used and can cause a cytokine storm. The cytokine storm overstimulates the immune system which results in fever, swelling and redness. It is believed that cytokine storms were the main cause of death for patients during SARS epidemic. =__Treatment and Response__= SARS does not have a vaccine or completely effective way to eradicate the disease from an infected individual. While treating the individual infected, health providers must be conscious of the transmission of the disease and must find a way to separate the patient from other non-sick people. One of the most effective ways to treat the disease symptoms of SARS is with antipyretics, which help to reduce fever. Steroids are sometimes used to help with swelling in the lungs and to help rid of dead tissue. There have been tests to find the most effective way to use antiviral medication to treat SARS, but it is not a proven way to treat it. SARS must be treated with attention to co-morbidity and attempt to reduce the severity of the symptoms. In order to ensure the halting of transmission of SARS, hospitals had to take a firm stance on the treatment protocols of SARS patients. Most hospitals utilized negative pressure or quarantine rooms to help prevent the spread of the disease through the hospitals. These rooms ensure that all the air that enters the room leaves from the same location and is then filtered for viral particles. These rooms were installed throughout hospitals in Hong Kong and were effective in ensuring that the disease did not pass. Another effective way of helping SARS patients was through advanced ventilator and breathing methods. Breathing and ventilator machines would help a patient overcome difficulty of breathing and other respiratory issues.
 * Introduction into a Cell**
 * After Introduction**
 * Cytokine Storm**
 * Medications Used**
 * Hospital Methods**

=__Contributing Factors__= When SARS first broke out in China, the government was wary of informing the international organizations and press. Because of China's position as a global powerhouse and up and coming superpower, China needed to protect its trade relations. With the outbreak of SARS, the Chinese government was afraid of how the sometimes fatal disease would affect trade. This reluctance caused a delay in treatment and inspired more fear from the Chinese citizens and international community. Without the help of the international science community, treatment and possible vaccines were delayed and the disease spread further. Also little notification of the disease allowed the disease to escape China and travel with visitors to the Southeastern China. Thus, a stigma surrounding people who were sick with SARS or people of Chinese heritage were questioned about their place in the epidemic. The Chinese government and economy hinges on its economic prosperity and trade, if knowledge of SARS broke out then all trade would be halted for an undetermined amount of time.
 * Cultural Factors**

Because of China's economic strength, the country's overall economic situation was not a large contributing in the outbreak. But China, like many other rapidly developing countries, has a large gap between the poor and the rich. Because of Hong Kong's sheer size and population, citizens are left in very close quarters creating the perfect environment for a virus obtained from close contact with the sick. Because of the amount of people who contracted SARS (8,098 people), many hospitals were unable to care for the sheer number of victims. Also it did not help that the virus was unknown and treatment was difficult for hospitals to define. Now in 2011, almost 1/5 of Hong Kong's population lives in poverty. The government of Hong Kong has been criticized for the living conditions that the poor citizens are living in. These conditions are often cited as "cages." Close quarters, poor living conditions and malnutrition are conducive to the spread of an infectious disease. The SARS coronavirus was not yet discovered and the virus had its first incarnation to cause the 2002-2003 outbreak. As the outbreak was happening, doctors and scientists were investigating the cause and best treatment for the virus. This left many people sick without means to stop the passing of virus, citizens began to wear masks. Most people began to wear masks and attempted to escape infection. Also the symptoms of SARS are very similar to the common flu, so many cases went under the radar when transported to other countries or even in mainland China. With SARS relative new presence, the citizens of China were left in a perpetual state of fear around the time of the outbreak. Also, SARS has an incubation period of 2 to 10 days and it is possible that someone could pass on the disease before they started to show symptoms. This would allow the disease to pass even before a sick individual sought treatment or medical attention. Hong Kong's place on the South China Sea makes it an important port for dissemination of goods to the rest of China. Without correct regulation of goods or products, a disease/virus can be obtained from the excessive amounts of trade in the global economy. The location of Hong Kong and Guangdong province is key to the start of the outbreak. The outbreak has been traced back to civet cats and civets are often sold in markets. These animals would have to pass through the Hong Kong to be sold to other countries or cities in China. The constant movement of travelers through the area also does not help halt the spread of the disease. SARS can easily be transmitted quickly and many people who have the disease may leave the country and spread it further.
 * Infrastructure and Economy**
 * Biological Factors**
 * Environmental Factors**

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