Introduction:
Covid-19 and SARS (Severe Acute Respiratory Syndrome) have dominated the news over different periods. Covid-19 was prevailing in the past few years. SARS marked the first pandemic of the twenty-first century. Both conditions are caused by RNA (ribonucleic acid) viruses belonging to the coronavirus family. These viruses are known to spread severe respiratory infections. Both states were first seen in China. SARS-CoVirus cause SARS, while Covid- 19 is caused by SARS‐CoV‐2.
What Is Coronavirus?
Coronaviruses are a diverse range of viruses with various hosts, including humans. The greatest variety of coronaviruses is seen in bats. The word 'corona' in Latin means crown. It refers to the spike-like projections on the surface of the virus. Coronaviruses cause mild respiratory conditions in humans. Four types of coronaviruses cause respiratory tract infections in humans.
What Is SARS?
The respiratory illness caused by SARS CoVirus is called SARS. The global outbreak of SARS happened from the end of 2002 to the middle of 2003. Bats are suspected to be the reservoir of the virus. Some experts say the virus had an intermediate host called the civet cat before jumping to the human. Fever is the most common symptom seen. The other symptoms can include;
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Cough.
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Fatigue.
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Body ache.
When the case worsens, it causes difficulty in breathing. Severe cases advance rapidly into pneumonia or respiratory distress.
What Are the Differences Between COVID-19 and SARS?
Some of the differences between Covid-1 and SARS can include;
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The incubation period (the time lapse between when the organism enters the body to when the first symptoms are seen) for the condition ranges from two to ten days, or an average of five days. The average latency for Covid-19 is a little longer.
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According to the World Health Organization (WHO), the average reproduction number for the Covid-19 virus is 1.9. It means that a person having the infection transmits the infection to another 1.9 people. On the other hand, the average reproduction number for SARS is 3.
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Studies show that despite the higher reproduction number of SARS, Covid-19 was more widespread than SARS.
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Covid-19 is more transmissible than SARS.
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Covid-19 is more prevalent in males than females. The male-to-female ratio for Covid-19 is 2.7:1. Conversely, SARS had a female predominance.
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The median age for Covid-19 was fifty-nine years, while for SARS, it was thirty-five years.
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About twenty percent of the Covid-19 patients needed to be hospitalized. Out of this, a smaller percentage required mechanical ventilation (assistance of a machine to make the lungs functional). In contrary to this, SARS was more severe. About twenty to thirty percent of people required mechanical ventilation.
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As per the Centres for Disease Control and Prevention (CDC) studies, Covid-19 can be spread even before people start showing the signs and symptoms, which is not so for SARS. No cases have been reported in SARS where the transmission happened before signs and symptoms appeared.
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The genetic information of the Covid-19 virus was similar tor resembled that of the bat coronavirus and the SARS virus.
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Studies show that the receptor-binding site of Covid-19 blinds to the host with a greater affinity when compared to that of the SARS virus.
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Diarrhea was reported in twenty-five percent of the patients with SARS, while intestinal symptoms were rarely reported in COVID-19.
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Studies show that patients with COVID-19 developed IgG within nineteen days of infection. The magnitude and durability of the antibodies in the severe form of the condition were higher, though the antibody was also detected in the milder forms. However, some studies show that this is short-lived.
What Are the Similarities Between COVID-19 and SARS?
The similarities between the two conditions can include the following;
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The initial signs and symptoms of the two conditions are similar. They include fever, cough, headache, shortness of breath, and difficulty breathing.
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Patients with both conditions developed lymphopenia (where the blood does not have sufficient lymphocytes) with a high level of pro-inflammatory cytokines like interleukin (IL)‐1b and IL‐6.
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The possible pathogens in both conditions were derived from wild animals. COVID-19 was transmitted from civet cats to humans, while SARS was transmitted from infected bats.
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Both conditions affect the lung epithelial cells. They used receptor-mediated endocytosis as an entry receptor through angiotensin‐converting enzyme II (ACE2). Receptor-mediated endocytosis is a process by which the cells absorb metabolites, hormones, etc., by the plasma membrane's inward budding.
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The immunopathogenesis of COVID-19 and SARS resemble each other.
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Infants and people over sixty years are at higher risk of developing the disease in both conditions.
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In COVID-19 and SARS, comorbidities like diabetes and hypertension increase the risk of the condition.
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Over-the-counter drugs were used in the treatment of both conditions. No standard medication or regimen has still been suggested.
How Serious Are the Two Conditions?
Both SARS and COVID-19 are contagious diseases. At times, they can advance to fatal respiratory illness. The mortality rate for SARS is about ten percent. Studies show that people older than sixty and those with pre-existing diseases are at a higher risk of complications. The mortality rate of COVID-19 is still under research. People above sixty years, immunocompromised, and those with health conditions like heart disease, diabetes, etc., are the ones that are negatively affected by COVID-19.
How Are the Two Conditions Treated?
Both conditions involve respiratory symptoms, which must be treated to prevent them from becoming severe. There is no standard method to treat the conditions, and they are treated symptomatically. Oxygen therapy must be required in severe infections. Mechanical ventilation must be needed in case of respiratory failure.
Conclusion:
SARS and COVID-19 spread through direct contact and droplet infection. Studies show that droplet infection can extend as far as three meters, as far as the droplets from an infected person can scatter. It can also spread when one touches the things touched by the infected person and then touches their eye, nose, or mouth. Practicing overall hygiene and avoiding unnecessary travel is recommended to prevent the spread of the two conditions. Use of sanitizer, proper washing of hands, etc., can help keep the spread under control.
