Over the past few weeks, the world has been in a state of public health emergency due to the outbreak of coronavirus diseases or COVID-19. Millions have been affected globally, with new cases diagnosed daily, and hundreds of thousands of mortalities emerging every day. Although the coronavirus family has been around for over 50 years, severe diseases associated with it have made it the most popular and the most feared virus at present.
About the Virus
The coronavirus was first described in detail in the 1960s, with the earliest detection of the virus found in infectious bronchitis in birds and the common cold in humans. Its name was derived from the Latin word corona or crown, which pertains to the crown-like appearance of its virions or infective form, as seen under electron microscopy. According to microbiologists, the globular appearance of its virus with its bulbous extensions or projections is similar to the appearance of a crown or a solar corona, thus its name.
There are currently four genera in the family of coronaviruses, namely the Alphacoronavirus and Betacoronavirus, which are known to infect only bats, pigs, cats, and humans, while the Gammacoronavirus infect mostly birds, and Deltacoronavirus infect both birds and mammals. Interestingly enough, the coronavirus family contains the longest genome of any RNA-based virus, which consists of a single strand of nucleic acid roughly 26,000 to 32,000 bases long.
Role in History
Through the years, research has led to new and updated information regarding the virus. Although associated with relatively mild cases of upper respiratory tract infections or the common cold, its more virulent strains have also caused severe illness and even death. With the different strains diverging from a common ancestor, the same type of illness was observed in both animal species and humans in history. Its relevance? A virus found in bats or bovine could also affect other animal species and even humans.
• 1500s: divergence of bat and human coronaviruses from the most recent common ancestor (MRCA)
• 1890s: divergence of the bovine coronavirus and human coronavirus from the MRCA
• 1950s: divergence of the bovine coronavirus and canine respiratory coronavirus from a common progenitor; identification of the most recent common ancestor or MRCA of the human coronavirus OC43
• 1960s: divergence of human and alpaca coronaviruses from the MRCA
• 2002: detection of the Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)
• 2012: detection of the Middle East Respiratory Syndrome Coronavirus (MERS-CoV)
• 2019: detection of the Novel Coronavirus causing Coronavirus Disease (COVID-19 or SARS-CoV2)
According to the Center for Disease Control and Prevention (CDC), coronaviruses have long been associated with common colds in adults and children but have also known to cause pneumonia and bronchitis. Currently, there are seven strains of human coronaviruses and are identified as:
1. Human Coronavirus 229E (alpha coronavirus)
2. Human Coronavirus OC43 (beta coronavirus)
3. Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)
4. Human Coronavirus NL63 (alpha coronavirus)
5. Human Coronavirus HKU1 (beta coronavirus)
6. Middle East Respiratory Syndrome Coronavirus (MERS-CoV)
7. Novel Coronavirus causing Coronavirus Disease (COVID-19 or SARS-CoV2)
The coronavirus is mainly spread through person-to-person transmission. The World Health Organization (WHO) mentions that the virus is mainly spread through respiratory droplets released into the air when coughing or sneezing, which a healthy person catches or directly comes in contact with, which usually happens when an infected person is near those around him. Specific situations which can lead to infection include:
· Coughing and sneezing without covering the mouth
· Touching or shaking hands with someone that has the virus
· Coming in contact with a surface or object that has the virus and then touching your nose, eyes, or mouth
· It may also spread through contact with feces on rare occasions
Coronaviruses have a period of incubation which can range from one (1) to 14 days. This means that a person can remain asymptomatic or without symptoms despite being a carrier. Research on the novel coronavirus, however, shows that incubation may last up to 24 days before observable signs and symptoms are reported or experienced.
According to the Chinese Journal of Epidemiology, certain risk factors have been identified in an individual that predisposes one to coronavirus infection. Males are more commonly affected, as well as those with pre-existing medical conditions such as cardiovascular disease, diabetes, chronic lung disease, hypertension, and cancer. Not only are these individuals more at risk of being infected, but they are also more likely to experience complications, which may lead to death. At present, the fatality rate increases with increasing age, with the highest recorded deaths in individuals 80 years old and above, followed by those in their 60s to 70s. No reported fatalities have been recorded for children 0-9 years old.
Signs and Symptoms
Coronavirus infection can result in a variety of symptoms in both humans and animals. The most common manifestations include cough and colds, a runny nose, and sore throat, all of which are characteristic of an upper respiratory tract infection. Although not commonly associated with coronaviruses, diarrhea and abdominal pain can also be some of its symptoms.
Severe illness has often been linked to coronavirus infection, such as SARS-CoV and MERS-CoV. As the name implies, patients with SARS-CoV were noted to experience severe influenza-like illnesses. This illness, originating from Guangdong, China, resulted in 800 deaths in 2002. MERS-CoV, on the other hand, displayed signs of severe respiratory illness presenting as fever, cough, and shortness of breathwith gastrointestinal symptoms (such as diarrhea) which resulted in more than 800 deaths.
According to WHO, coronavirus disease or COVID-19, previously known as the Novel-Coronavirus of 2019 or NCoV-2019, mainly presents with respiratory symptoms such as cough and shortness of breath with fever. In severe cases, infection leads to pneumonia and severe acute respiratory syndrome. This has also been associated with impaired liver and kidney function, leading to kidney failure and even death. Among the three severe illnesses associated with the coronavirus, the COVID-19 has affected the most number of individuals in 38 countries worldwide, with close to 81,000 cases, and 2,800 deaths attributed to it. Scientists say it has yet to show signs of slowing down.
Due to the pressing need for fast and easily accessible tests to diagnose COVID-19, the CDC has developed a new laboratory test kit called CDC 2019-Novel Coronavirus Real-Time Reverse Transcriptase (RT)-PCR Diagnostic Panel, which is intended to be used for upper and lower respiratory specimens collected from persons who meet the screening criteria for COVID-19.
According to the CDC, not all patients or individuals should be subjected to testing. The first criteria for testing cover patients presenting with fever AND symptoms of lower respiratory illness such as cough or difficulty of breathing AND has traveled from Wuhan, China within the past 14 days OR was in close contact with a person under investigation for COVID-2019 within the last 14 days while that person was ill. The second criteria cover patients with fever OR symptoms of lower respiratory tract illness AND were in close contact with an ill, laboratory-confirmed COVID-2019 patient within the last 14 days. Once an individual meets any of the mentioned criteria, further diagnostic procedures are to be performed immediately while the patient is kept in isolation.
Although several preventive measures have been described, the basic principles of illness prevention, no matter what type of disease or strain of microorganism, remains constant. WHO and CDC both agree on the following measures to prevent the spread of COVID-19:
· Wash hands thoroughly with soap and water for at least 20 seconds. If soap and water are not available, use an alcohol-based hand sanitizer or alcohol itself, with at least 70% alcohol content.
· Avoid touching your eyes, nose, and mouth with unwashed hands.
· Avoid close contact with people who are ill.
· Practice proper respiratory etiquette. Cover cough or sneeze with a tissue, making sure that the used tissue is discarded properly. Make sure that hands are properly washed right after.
· Clean and disinfect frequently touched objects and surfaces, then make sure hands are washed after cleaning or disinfecting. It is also advised that one wears gloves when at risk of being exposed to sick individuals.
· Seek medical attention if with symptoms and travel history to places with confirmed cases of COVID-19 or if with exposure to patients who were ill and fall under the category of a person under investigation.
Viruses are often self-limiting with infections resolving on their own. Although anti-virals are available, not all viruses can be treated with the same medication. In the case of COVID-19, no specific antiviral treatment is recommended. Currently, only symptomatic and supportive care are given as well as respiratory and contact isolation for infected individuals.
Fighting Off the Virus
Although WHO stresses the risk of infection to be higher in areas where several individuals have been diagnosed with COVID-19 and the infection rate in other parts of the world are currently low, it is still best to take the necessary precautionary measures and maintain health at its optimum to fight off this disease. This includes:
· Getting adequate sleep of at least 6 to 8 hours daily
· Eating nutritious food specifically those that are high in antioxidants (fruits and vegetables)
· Staying hydrated with at least 8 glasses of water daily (Studies show that well-hydrated ill patients recover faster compared to those who lack hydration)
· Supplementing with vitamin C and zinc helps boost one’s immunity and also leads to shorter periods of illness according to the Journal of Biochemistry and Biophysics
· Increasing one’s physical activity to stimulate hormones that help fight off infection
At present, what is essential is to stay well-informed and well-equipped, whether in mind or in body, on whatever this virus may bring next.