The accelerating and perpetuating Coronavirus of 2019, also known as COVID-19 or SARS-CoV-2 has left the world devastated in a matter of just a few months. With its respiratory acquired symptoms, transmission is from human to human through airborne acquisition. The virus is considered a pandemic and WHO declared a public health emergency of international concern (PHEIC) on January 30, 2020. The origin of COVID-19 comes from Wuhan China and WHO first alerted pneumonia cases in Wuhan on December 31, 2020. From the structure, to problematic symptoms, the virus has a lot of characteristics to know. Despite there being studies still yet to be done, understanding the origin, mechanism, pathophysiology and symptoms can really inform the public about this ongoing pandemic and the implications in today’s society.
Before understanding how to be treated and how you know if you have the virus, it’s important to understand the similarities and differences the COVID-19 is from similar viruses such as SARS and MERS. First, they are all considered respiratory syndromes and have been transmitted by a bat reservoir. For example, the SARS (Severe Acute Respiratory Syndrome) occurred from 2002-2003 in China and the MERS (Middle Eastern Respiratory Syndrome) occured in 2012 in Saudi Arabia. Additionally, the intermediate animals hosts for wide variety of viruses included horses, pigs, camels, and civets. The late SARS virus’s intermediate host included civets, but today’s SARS-CoV-2 does not yet have a definitive intermediate host. However, some researchers suspect a pangolin as a probable host. Now, even though the intermediate host is still not exactly known, there is much to learn about the bat-the reservoir.
There are a lot of interesting facts concerning the bat reservoir and its implications in immune response and tolerance. To begin, bats have an average of about forty-three years and have a decrease rate in tumor genes. Bats play a major role in the COVID-19 as well as other strains of viruses because it serves as a reservoir for a large number of viruses dating back to Hendra in 1994. A disadvantage for humans, but an advantage to the bat is that the bat has a good immune system, making them have a longer life span and better rate of survival.
It’s also important to understand the structure of the virus to get a better understanding of the mechanism in action. Corona viruses are a family of viruses that have a crown around the membrane, giving them the distinct name of “corona” and is considered a community acquired respiratory infection because of its ability to spread from person to person through respiratory droplets. There are few major corona viruses that have impacted the world including HCoV-NL63, HCoV-229E, HCoV-OC43, HCoV-HKU1, HCoV-EMC, and now COVID-19. All of these viruses are single stranded enveloped RNA viruses that mutate fast. Additionally, the structure includes a spike glycoprotein (S), M protein, hemagglutinin-esterase dimer (HE), and an RNA and N protein, as well as an E protein.
Each of the corona structures on the virus serve a different role. For example, the E protein is involved in assembly, budding, and pathogenesis. As a result, viruses that lack the E membrane protein are good candidates for vaccines. However, the COVID-19 has an E membrane protein making it hard to come up with a vaccine, but there is still research to be done. The Spike protein (S) allows the membrane to attach to the host and as a result affects the host’s immune system. Viruses can be inactivated by alcohol and hand sanitizer, making washing hands imperative during times of person to person interaction.
It’s also important to understand the pathology of COVID-19 at a deeper level. For example, we already mentioned that the disease is spread from animals to humans. There are certain symptoms that are common and more severe to patients. However, there are also certain patients who are asymptomatic. To begin, the three most common symptoms that are similar across patient to patient include fever, dry cough, and fatigue. However, severe symptoms include high fever, cough with blood, decrease in white blood cells, and eventually kidney failure. On the other hand, there are certain symptoms that are uncommon to a patient. For example, some uncommon symptoms include nasal congestion, headaches, sore throat, shortness of breath, and pain in the muscles and joints.
There is also different laboratory testing done for coronavirus. First, the laboratory scientist has to do pre-analytical, analytical and post-analytical. The preanalytical starts with collecting quality specimen samples. The samples are either collected through the nose or pharyngeal way. However, it’s important to have a good distance from the patient in order to prevent possible transmission to the lab worker. The analytical part of the testing involves testing the actual sample. Culture is the gold standard for testing, but it takes a long time. researchers are also moving toward rapid antigen detection testing through urine samples for the future and it takes as little as 10 minutes. In addition, laboratories also use PCR, multiplex PCR and LAMP to identify specific targets and internal controls. Serology is also aimed to be used in the future for confirmation testing.
Note: I had an assignment on coronavirus and decided to share what I found. The above information is from an ongoing corona webinar series through lab roots. However, feel free to check out the WHO (World Health Organization) website for more information.
https://events.labroots.com/event/Coronavirus2020/en-us#!/Lobby.
https://www.who.int/