Author: Prof. Dr. Mustafa Asim Safak
-Memorial Hospital ENT Clinic, Antalya-
-Near East University Faculty of Medicine, ENT, TRNC-
Some mutated species of the Coronavirus family, which is commonly accepted as a disease agent in animals, can also cause diseases in humans. We have witnessed examples of this as SARS in 2002 and MERS in 2011, both of them being severe lower respiratory tract infections. The causative pathogen of the disease, which has become a pandemic (a worldwide epidemic) today, is named the SARS-CoV2 virus, and the disease it causes is COVID-19. It causes serious lower respiratory failure, as in previous examples, and may damage the central nervous system in the early period, unlike the previous ones.1 Like other members of the Coronavirus family, this virus has a sheath called the envelope in its fat structure, which has spiky protrusions of its protein structure on its outer surface. Because it looks like a “crown” due to these spiky protrusions, it is referred to as “corona”, meaning crown (figure). The spiky proteins of the SARS-CoV2 virus differ from the SARS virus by 2% and provide much better adhesion to human cells.2 The virus is a non-living pathogen agent with its nucleic acid chain (a kind of helical amino acid chain that carries genetic codes) in the envelope. The virus can replicate itself, cause damage, and spread only when it infiltrates into another cell. For the SARS-Cov2 virus to infiltrate into cells, its envelope structure must be strong. The virus becomes harmless as oil solvents such as soap or detergent damage the envelope structure. It can remain infectious for only a few days if it cannot infiltrate into the cell provided that its envelope structure is strong. The exposed virus is deformed over time and becomes ineffective. When a sufficient number of SARS-CoV2 enters the human body, the infection begins once the virus clings onto the surface epithelium (a skin-like but much thinner, a single layer of cell covering the inner cavities of our body) and then infiltrates the cell.3
Modes of Transmission
It is proven that the virus is transmitted by airborne droplet infection and through contact with infected surfaces. Furthermore, although it has been demonstrated that the live virus has excreted from the human body through feces within 12 days of the onset of the disease, it has not been proven to be transmitted that way.3 The live virus has not been demonstrated in blood and urine and does not exhibit infectious properties. The disease is not transmitted by blood and blood products, or by mosquitoes or other bloodsucking parasites.4 Yet it is transmitted from person to person, and infectiousness begins even when the person who is sick has not yet developed symptoms.5 There is no consensus on the effects of climate and weather conditions on the contagiousness of the disease. There are scientific studies indicating that increased air temperature and humidity reduce the speed of propagation of the disease.6 However, some authors report that this would not be effective.4
Age and Gender
42% of the patients that received a final diagnosis are between the ages of 18 and 40. A closer look at the general breakdown of diagnosed cases by age shows that there is a noticeable accumulation among older people. In general, the disease tends to be more severe in people with chronic diseases such as diabetes, heart and kidney failure, or undergoing cancer treatment or in cases where the immune system is suppressed or in older people. However, 40% of patients still consists of people under the age of 55.7 Therefore, it would be wrong to think that it mostly affects persons of rather advanced age. On the other hand, it progresses more severely in older people with more severe results.
The proportion of child patients diagnosed (under 18 years of age) to all patients is reported to be 2.4%.8 The reason why we have such a statistical result is that there are more cases that are overlooked because the disease is much milder in childhood. This is mainly due to the fact that vaccination programs are mostly implemented in childhood. The lack of fully-developed cellular mechanisms that allow the virus to infiltrate into the cell may also be a factor providing children with natural protection.8 It has not been demonstrated that the virus is transmitted from sick mothers to the child through pregnancy.
Men contract the disease more than women, and about 60 to 70% of mortality is seen among men. As a cause of this, some have suggested that chronic diseases and the habit of using tobacco are more common in men. Furthermore, the estrogen hormone, which is more abundant in women, is estimated to have an influence on this. However, it is likely that the main reason is the genes related to the immune system are mostly located on the X chromosome, which is the sex chromosome.9 Women have two X chromosomes while men have only one.
The period between the introduction of the virus into the body and the onset of symptoms is called the incubation period, which is about 4 to 7 days in the majority of cases and can vary from 2 to 14 days when COVID-19 is concerned.10 Symptoms include fever in 80 to 90% of cases, cough in 60 to 70% of cases, gastrointestinal complaints in 40 to 50%, loss of smell in 30 to 40% and shortness of breath in 20%.11 Not all these symptoms are necessarily observed. Furthermore, it is estimated that one can have the disease and recover without any of the symptoms hitting the surface. For example, some cases only progress with gastrointestinal symptoms without any fever and respiratory complaints, and in such cases, it may take longer for the patient to recover.11 Fever and shortness of breath seem to be the most significant symptoms. Patients who do not develop respiratory distress recover in about a week. Recovery time may extend up to 2 weeks in patients whose fever cannot be controlled.
In general, the clinical picture may exhibit itself in 4 different ways:10
- Mild cases – Symptoms are almost non-existent and the patient has absolutely no breathing difficulties.
- Moderate cases – The patient has a fever as well as radiological signs of pneumonia. Almost 80% of all cases are in the mild and moderate group.
- Severe cases – The respiratory rate is more than 30 per minute and the oxygen saturation is less than 93% at rest. Radiological signs of pneumonia grow worse by more than 2 folds within 1 to 2 days. About 14% of all cases are in this group.
- Critical cases – Ventilation in the ICU is required. The patient develops shock and/or multiple organ failure. Fortunately, only about 6% of all cases are in this group.7
Suspect Case Definition and Diagnosis
The suspect case definition updated multiple times by the Ministry of Health of the Republic of Turkey is as follows: Fever accompanied with cough and/or shortness of breath, or contact with a patient diagnosed with Covid-19. There are two different definitions here, involving either “a person with close contact” or “a person with contact”.
The definition of a person having close contact without protection includes the following:
- Those who provide care to a confirmed or suspect case
- Those visiting sick people
- Students and teachers in the same school environment as sick people
- People who had skin contact and/or shook hands with sick people
- People who come into contact with the saliva or body secretions of sick people
- Those who stay in the same indoor environment as sick persons at a distance of less than 1 meter for more than 10-15 minutes
- Passengers who travel within two rows to the front, back or side on the same plane or bus as sick persons
- Those living in the same home as sick persons
- Those working in the same office as sick persons
The definition of a person having contact without protection includes the following:
- Those who stay in the same indoor environment as sick persons at a distance of more than 1 meter
- Those who stay in the same environment as sick persons for less than 10 minutes
- Those who stay in the same indoor environment as sick persons at a distance of less than 1 meter for less than 10-15 minutes
Diagnosis can be made by demonstrating the virus in the secretions from the nose, throat, or lower respiratory tract (RT-PCR test) of people who fall within the scope of suspect case definition due to their complaints and symptoms.10 The sensitivity of this test may drop to 70% in the early stages of the disease and may not give positive results for all patients.3 It is required to evaluate the chest x-ray or CT scan images of patients who are more practically suspected. Although the definitive diagnosis cannot be made according to the results of the x-ray, it can demonstrate a high match with RT-PCR test12 and thus indicate possible disease earlier during the pandemic.10 Serological tests for the investigation of early specific antibodies (IgM) generated by our virus defense system are also in question and can turn positive on day 3 to 5 following the onset of symptoms.10 Making a retrospective diagnosis following the recovery of patients is also possible following research on late specific antibodies (IgG).10
For protection against the disease, a collective social observance of the individual measures is equally as important as those measures themselves. It is critical for containing the spread of the disease to isolate and treat diagnosed cases and isolate those who had contact with sick persons. It is recommended to isolate those who had contact with diagnosed cases. Those who had close contact with a suspect case need to be isolated until the test results of the suspect case are available. If the test results are negative, isolation is ended. The isolation period must be at least 14 days due to the incubation period. It is through contact tracing efforts that patients and the persons they contacted are identified. The morbidity increase during the pandemic can be controlled through contact tracing and isolation.13 This enables efficient use of the available healthcare institutions and the health personnel capacities that can combat the pandemic, thereby preventing an overburdening and halt of the healthcare system in a country. Therefore, as individual members of society, we all need to act responsibly and support this goal together.
Below is a brief list of protection measures:14
- Isolation and proper patient care
- Hand hygiene
- Surface cleaning
- Waste management
As a personal protection method, it grows very important for all patients or healthy people to wear a mask that covers their mouth and nose. Healthcare personnel who are involved in the treatment of patients must use more specialized masks, glasses, visors, and special gowns. The spread of saliva and droplets from the respiratory tract can be prevented when sick individuals use masks. This proves to be a very effective method of preventing the environment from being infected. Viruses in the airborne droplets that spread when sick people sneeze and cough can hang in the air for up to 3 hours. These particles then land due to gravity and infect all the surrounding surfaces. Sneezing or coughing directly into someone else’s face may cause that person to catch the disease through their eyes as well. To prevent that, using glasses can be protective. In addition, frequent ventilation of indoor environments is crucial in terms of cleaning the virus load in the air.
Viruses suspended in the air can reach the respiratory tract of healthy people during breathing. Moreover, the burden of the virus (number of viruses) entering the body at that point is naturally of great importance. In order to contract the disease, a very high number of viruses must reach our respiratory tract. Therefore, contracting the disease from the air in indoor environments is much more likely than in well-ventilated environments or outdoors.
It also gets more important how close we are to a sick person and how long we have been that close. Maintaining the distance between people is expressed as social distancing, which should be more than 1.5 – 2 meters especially indoors. Practically, the further away we keep from sick individuals, the less likely we are to contract the disease. The use of masks by healthy people at this stage can also prevent the droplets from reaching our respiratory tract and the virus load can be reduced considerably depending on the feature of the mask used.
In social life, it is very important to use a mask that basically closes the mouth and nose. Masks made of various fabrics can particularly prevent the spread of the infection to a great extent when used by sick people. There is not a specific type of mask that must be selected. The use of even the washable and reusable masks is significantly effective in preventing the spread of the infection.
It is recommended for healthy people to use masks especially indoors, preferably surgical masks or even specialty masks with advanced filtration, if available. To that end, masks that can filter particles smaller than 3 microns gain importance in order to keep away extremely small viruses.
Healthcare personnel treating patients or relatives caring for their patients must absolutely use specialty masks. Specialty masks available include N95 (FFP1), N97 (FFP2) and N99 (FPP3), which can filter out coronavirus by 95%, 97% and 99% respectively. It is especially important for healthcare professionals to use FFP2 or FFP3 masks. These masks can effectively be used for approximately 8 hours. At the end of this period, they need to be replaced. Some studies suggest that it is appropriate to reuse such masks once or twice after sterilizing them for about 15 to 30 minutes with UV rays, since they cost more and are not very easy to procure.25
Adequate protection cannot be taken for granted even if sick and healthy individuals alike use masks and comply with social distancing requirements. The disease can be transferred from infected surfaces to our mouth, nose or eyes via our hands. Therefore, it is crucial not to touch our mouth, nose and eyes with our hands. If we have lesions on our hands such as wounds that disrupt the integrity of the skin, it may be possible for the virus to enter our bodies through such gates. In such cases, it may be useful to use gloves to touch surfaces the cleanliness of which you are not sure about. Considering the biological structure of the virus, the oily envelope structure that forms its outer surface can be disintegrated with soap and detergent. Therefore, washing our hands with soap for 20-30 seconds when we think they are dirty eliminates the ability of viruses to infect. We can use our personal towels or paper towels or hot dry air currents. Hot dry air currents do not clean hands by themselves.4 Apart from washing our hands with soap, alcohol-based hand disinfectants are also known to disrupt the envelope structure of the virus and eliminate its ability to infect.
Viruses can remain on the infected surfaces for days at a quality and quantity that can maintain their infectivity.3 In a study on SARS-CoV2, it is found that the virus can survive up to 3 days on plastic and steel surfaces, up to 24 hours on cardboard and up to 4 hours on copper.15 However, this does not mean that the infectivity of the virus continues throughout such periods. The infectious potential is approximately 60-70 minutes suspended in the air, 45-50 minutes on copper, 3-4 hours on cardboard, 5-6 hours on steel and 6-7 hours on plastic.15 Therefore, it is scientifically considered sufficient to keep the purchased products outside for a few hours before they are brought into the house. It is not deemed necessary to disinfect the products by washing them with detergent or soap.
Soap, detergents and diluted bleach can be useful for surface cleaning. However, even though the use of vinegar as a cleaning agent has an effect on parasites, it is known that it has no effect against the coronavirus.
The virus can be transported from infected surfaces by contact, but the duration of contact and the humidity of such surfaces also matter. It takes about 10 seconds of contact time to become infected by touching a dry surface with our dry hand. In other words, we are not immediately infected by touching an infected surface for 1-2 seconds and then quickly stopping contact. The time needed for such infection to take place can be as short as 5 seconds if one of the contacting surfaces is moist, and 3 seconds if both are moist.16 Furthermore, it is known that the virus loses its infectiousness when exposed to direct sunlight for more than 30 minutes.
Protection with Medication
If there is intestinal involvement in COVID-19, diarrhea and abdominal pain occur. Although there are no symptoms of the gastrointestinal tract as a symptom of the disease, diarrhea may develop since bowel functions are impaired as a side effect of the agents used for treatment. In such cases, it is useful to use probiotics to protect and reinstate the intestinal flora.17
Hydroxychloroquine molecule has been used for the treatment of malaria for years and is publicly known as quinine. It is also used for the treatment of certain joint diseases. It was demonstrated back in 2006 that quinine was effective in the treatment of coronavirus infections. It is suggested that this drug, which is approved for use in the treatment of COVID-19, may also have prophylactic effects in high-risk people when used at very small doses (200 mg every 3 weeks).18 However, it is reported that if this drug is taken as prophylaxis, it may cause delays in diagnosing the disease as well as resistance to other drugs if the disease is contracted. It is useful to get professional help from physicians instead of acting on our own for protection with this type of medication.
Vitamins can be beneficial within the diet. It is reported that the IV administration of vitamin C as an antioxidant, especially in high doses, will be beneficial in severe cases.19 Based on this, researchers suggest that dietary supplements such as vitamin C20 and D21 can be effective in preventing disease.
There are studies suggesting that eating bitter vegetables or drinking the likes of coffee and tea, which can all be defined as bitter by taste receptors on our tongue, may be useful in preventing COVID-19.22
If patients cannot be fed orally, it is important for the intestinal flora to continue feeding via the feeding tubes that go through the nose and into the stomach. More specific nutritional solutions should be chosen in cases where intestinal absorption is impaired.17 In cases that cannot be fed orally, the option of IV serum feeding should be selected.
Although 70% alcohol is effective to clean infected surfaces and ensure hand hygiene, drinking alcohol does not disinfect the mouth and throat, fails to decrease the likelihood of contracting the virus and may even be harmful as it can negatively affect your immune system.4
In particular, it is reported that obesity at a young age worsens the course of COVID-19 and increases resistance to treatment as well as morbidity.23 Obesity not only causes chronic inflammation (inflammatory reaction in tissues) by itself but also sets the basis for diabetes, which can make an impact in the course of the disease.
Isolation has emerged as one of the best protection methods. Staying as far away from infected people as possible not only reduces our chances of contracting the disease but is also crucial in terms of preventing the spread of the disease socially. Contrary to popular belief, it is not proven that exposure to temperatures above 25 degrees or sunbathing will prevent contracting the disease. Similarly, cold weather and extreme winter conditions do not affect the spread of the virus and the transmission of the disease. Neither taking a shower with hot water or going into a Turkish bath or sauna are effective in treating the disease nor do they reduce its contagiousness.4
No dedicated vaccine has yet been developed for Covid-19. However, based on the data obtained from 178 countries in the world, recent studies show that the incidence rate of COVID-19 is lower in countries where the TB vaccine (BCG) is commonly applied compared to other countries. In addition, it is reported that mortality rates are 10 times lower thanks to early-age BCG vaccination.24 This study suggests that the immune system (immunity) can grow stronger following BCG vaccination in childhood and thus COVID-19 may at least be milder in persons vaccinated this way.
However, seasonal flu vaccines do not ensure any protection against COVID-19. Yet it is predicted that they can be useful for our body resistance since they are able to reduce our likelihood of catching other flu types.