SARS, or severe acute respiratory syndrome, is a zoonotic respiratory disease caused by the severe acute respiratory syndrome coronavirus (SARS-CoV or SARS-CoV-1), the first strain of the SARS coronavirus genus severe acute respiratory syndrome-related coronavirus (SARSr-CoV). In late 2017, Chinese scientists in Xiyang Yi Ethnic Township, Yunnan, traced the virus back to cave-dwelling horseshoe bats through Asian palm civets.
Origin of SARS Virus
In late May 2003, researchers in Guangdong, China, used samples of wild animals sold as food in a local market.
The SARS coronavirus could be isolated from masked palm civets, even though the animals did not display clinical symptoms of the virus, according to the findings.
SARS virus crossed the xenographic barrier from Asian palm civets to humans, killing over 10,000 masked palm civets in Guangdong Province, according to preliminary findings.
Raccoon dogs, ferret badgers, and domestic cats were later found to bear the virus.
Two studies published in 2005 found a number of SARS-like coronaviruses in Chinese bats.
SARS coronavirus most likely originated in bats and spread to humans either directly or by animals in Chinese markets, according to phylogenetic analysis of these viruses.
Although the bats showed no signs of disease, they are likely natural reservoirs for SARS-like coronaviruses.
Scientists from Hong Kong University's Chinese Centre for Disease Control and Prevention and the Guangzhou Centre for Disease Control and Prevention discovered a genetic link between the SARS coronavirus found in civets and humans in late 2006, supporting claims that the disease had crossed organisms.
Researchers announced in December 2017 that they had discovered a remote cave in Xiyang Yi Ethnic Township, Yunnan province, which is home to horseshoe bats that bear a strain of a virus known as a coronavirus, after years of searching throughout China, where the disease first appeared.
This strain has all of the genetic components of the SARS strain that caused the global outbreak in 2002.
In bats, the virus was ephemeral and seasonal. During the outbreak, a small number of cats and dogs tested positive for the virus. These animals, on the other hand, did not spread the virus to other animals of the same species or to humans.
Transmission of SARS Virus
SARS is an infectious virus that spreads by tiny droplets of saliva, much like the common cold and influenza virus. SAR virus can also be transmitted indirectly by touching surfaces that have been contaminated with the virus. SARS-CoV's basic reproduction number R0 varies from 2 to 4 depending on the study.
Symptoms of SARS Disease
SARS has an average incubation period of 4–6 days, although it can be as short as 1 day or as long as 14 days in extreme cases.
The majority of SAR virus-related deaths are caused by respiratory failure. SARS can also cause liver and heart failure. People over 60 who have been diagnosed with another chronic illness are the most vulnerable to complications.
Common Symptoms of the SARS Virus are:
SARS Virus Diagnosis
The SARS virus has been detected using a variety of lab tests. There were no laboratory tests available for SARS during the first outbreak. Symptoms and medical history were used to make the diagnosis. Nasal and throat swabs, as well as blood samples, can now be used in laboratory research. A chest X-ray or CT scan can also show symptoms of SARS-related pneumonia.
Prevention of SARS Disease
SARS does not have a vaccine. There is no cure that has been shown to work for anyone who has SARS. Antiviral drugs and steroids are often used to help with lung swelling, but they aren't always effective. If required, additional oxygen or a ventilator can be prescribed. Blood plasma from someone who has already healed from SARS can be used in extreme cases. However, there is insufficient evidence to demonstrate that these therapies are successful. Clinical isolation and quarantine are still the most important ways to stop SARS from spreading.
As we all know that prevention is better than cure and if you are in close touch with someone who has been diagnosed with SARS, here are some of the best ways to avoid SARS transmission:
Handwashing with soap and water or the use of an alcohol-based hand sanitiser.
Disinfecting the surfaces with an alcohol-based sanitiser.
Avoid contact from the body fluids of an infected person.
Washing a person's personal belongings in clean, soapy water if they have SARS.
Keeping children who are having symptoms at home.
Simple hygienic practices
Isolating oneself as much as possible to reduce the possibility of virus transmission.
Many public health efforts have been made in an attempt to monitor the spread of the disease, which is primarily spread by respiratory droplets in the air that are inhaled or deposited on surfaces and then transferred to the mucous membranes of the body. Early identification of the disease, isolation of infected individuals, droplet and touch measures, and the use of personal protective equipment (PPE), such as masks and isolation gowns, were among the strategies. According to a 2017 meta-analysis, wearing a mask will minimise the risk of becoming sick by up to 80% for medical professionals as compared to not wearing one.
SARS-CoV is most contagious in patients who are seriously ill, which typically happens during the second week of illness. Quarantine was highly successful because of the delayed infectious period; people who were isolated before day five of their illness seldom spread the disease to others. Despite the fact that no cases had been confirmed since 2004, the CDC is still working to develop federal and local rapid-response protocols and recommendations in the event that the virus reappeared in 2017.
Treatment for SARS Disease
Antibiotics have no direct effect on SARS since it is a viral disease, but they can be used to treat bacterial secondary infections.
Antipyretics, supplementary oxygen, and, if possible, mechanical ventilation are used to treat SARS.
Ribavirin is widely used to treat SARS, but it seems to have little to no effect on SARS-CoV and has little effect on patient outcomes.
There is currently no antiviral therapy that has been proved successful. Ribavirin, lopinavir, ritonavir, and type I interferon have all been tested and have so far shown no definitive link to the disease's progression.
In patients with a serious disease and O2 saturation of less than 90%, the British Thoracic Society recommends corticosteroids.
To minimise the risk of medical staff being infected, people with SARS-CoV must be separated, preferably in negative-pressure rooms, with full barrier nursing measures taken for any required interaction with these patients.
Natural ventilation by the opening of doors and windows has been shown to help reduce virus particle concentrations indoors in some situations.
Any of the more severe effects of SARS may be attributed to the body's immune system responding in a cytokine storm.
The first case of atypical pneumonia was recorded in the Guangdong province of southern China on November 16, 2002.
The World Health Organization (WHO) issued a global warning on March 12, 2003, for an extreme form of pneumonia with an unknown cause in people from China, Vietnam, and Hong Kong.
The Centers for Disease Control and Prevention (CDC) activated its Emergency Operations Center (EOC) on March 14, 2003, and on March 15, 2003, it issued its first health warning and hosted a media telebriefing about atypical pneumonia known as Severe Acute Respiratory Syndrome (SARS). The CDC has issued provisional SARS recommendations for state and local health departments.
The CDC provided infection control precautions for aerosol-generating procedures on patients suspected of getting SARS on March 20.
The CDC released interim laboratory biosafety recommendations for handling and processing SARS specimens on March 22.
SARS could be caused by a new coronavirus, according to the CDC laboratory study published on March 24.
On March 27, the CDC released provisional domestic recommendations for the management of SARS exposure in healthcare and other institutional settings.
The SARs outbreak became more prevalent on March 28. SARS epidemic preparation starts at the CDC.
The CDC updated its SARS travel advisory on March 29th to cover all of mainland China as well as Singapore. Quarantine personnel at the CDC started meeting flights, cargo ships, and cruise ships arriving in the United States either directly or indirectly from China, Singapore, and Vietnam, as well as issuing health warning cards to passengers.
On April 4th, 115 suspected SARS cases in the United States were registered from 29 states. In the United States, there were no deaths associated with these alleged SARS incidents.
The CDC formed a community outreach team on April 5 to counter the stigma associated with SARS.
The CDC provided detailed advice for students who had been exposed to SARS on April 10th.
On April 14th, the CDC released a sequence of the virus suspected to be responsible for the global SARS epidemic. The genetic sequence of a new virus must be known in order to cure and prevent it. The findings were revealed just 12 days after a team of scientists and technicians began working around the clock to cultivate cells from a SARS patient's throat culture.
Health alerts were issued by CDC for travellers to Toronto, Canada on 22nd April.
On the 6th of May in the United States, no new probable cases had been identified in the previous 24 hours, and there had been no proof of continuing transmission for more than 20 days after the initial case reports in travellers. In the United States, containment has been successful.
The CDC lifted the travel advisory for Toronto on May 20 after more than 30 days had passed after the last confirmed case's onset of symptoms.
The CDC issued a new travel warning for Toronto on May 23 after Canadian health officials confirmed a cluster of five new probable SARS cases on May 22.
On June 4, the CDC removed the Singapore travel alert and downgraded the Hong Kong traveller warning from a travel advisory to a travel alert.
The CDC lifted the travel alert for mainland China on July 3rd.
On July 5, the WHO declared the global SARS epidemic to be under control.
The CDC lifted the travel alert for Hong Kong and Toronto on July 10th.
The CDC lifted the travel alert for Taiwan on July 15th.
The CDC revised the SARS case classification on July 17th, halving the number of cases in the United States. The move is due to the absence of cases where blood tests were taken more than 21 days after the start of illness and tested negative.
WHO issued SARS reports from 29 countries and regions on December 31st, resulting in 8,096 people with probable SARS and 774 deaths worldwide. In the United States, laboratory tests revealed eight SARS infections, with an additional 19 SARS infections suspected.
The CDC issued a Notice on Civet Embargo on January 13, 2004. Civets captured in areas of China where the SARS outbreak started were found to have a SARS-like virus. Civet imports are prohibited by the CDC. The civet is a cat-like creature with long legs, a long tail, and a masked face that resembles that of a raccoon or weasel. The prohibition is still in force.
SARS coronavirus was named a select agent by the National Select Agent Registry Program on October 5, 2012. A select agent is a bacterium, virus, or toxin that poses a significant risk to public health and safety.
SARS first appeared in China in 2002. Within a few months, it had spread all over the world, but it was quickly contained. SARS is a virus that travels through the air when a person with the disease coughs, sneezes, or speaks. Since 2004, there has been no known transmission. Symptoms include a fever, a dry cough, a headache, muscle aches, and trouble breathing. There is no treatment for SARS except for proper care and support.