Intense measures taken in the past two years, interruption of face-to-face education, and curfews have led to a serious decrease in the incidence of upper respiratory tract infections. However, factors such as the continuation of daily life, students resuming education in schools, unstable weather conditions, and neglected influenza vaccines have caused a noticeable increase in influenza and upper respiratory tract infections in recent months.

Although COVID-19 is the first thing that comes to mind when we say disease since March 2020, many other ailments continue to exist. Like the recent increase in upper respiratory tract infections... Answering what lies behind the resurgence of these ailments, which we almost forgot about last year, Yeditepe University Kozyatağı Hospital Internal Medicine Specialist Prof. Dr. Yaşar Küçükardalı said, “In the period when COVID-19 first started, there was a great decrease in seasonal influenza cases with strict compliance with isolation, mask, distance, and hygiene rules. However, nowadays, due to the fact that vaccination for COVID-19 has reached a certain rate, its speed has been slowed down, albeit partially, and the number of individuals with immunity has increased in the community, and a little more normalization has been achieved. In addition to all these, with the transition to face-to-face education in schools, there has been a certain increase in seasonal influenza cases in recent months compared to the last two years.”

Are factors such as the full-time opening of educational institutions and the increase in the time spent indoors without masks effective in the occurrence of these diseases?

Influenza, or seasonal influenza virus, has an incubation period of about two to three days. However, the incubation period of the COVID-19 virus varies between four and six days. Therefore, the influenza virus spreads faster and is transmitted more quickly. During this period, contact between people, especially the period of being in public places, should be kept as limited as possible. It is also of great importance to strictly continue the mask, distance, and hygiene measures. In terms of behavioral characteristics, there are also differences in age groups when COVID-19 is compared with the influenza virus as the influenza virus affects the children's age group more and they can be carriers. We cannot say that COVID-19 affects this age group as much as influenza, and there is no data in this regard. Therefore, the increase in influenza infections with the opening of schools results in the spread of infection among children in other populations, namely family members.

What are the Symptoms That Distinguish the Influenza from COVID-19?

Although COVID-19 and the influenza virus are different from each other, they also have common features. Both prefer the respiratory tract, starting with symptoms such as cough, nausea, vomiting, and diarrhea, as well as sore throat, head, muscle, and joint pains. On the other hand, there is a difference in the incubation times, and seasonal flu also called influenza, gives symptoms a little faster after being infected compared to COVID-19. There are two types of these viruses, A and B. Influenza A virus is the most common cause of influenza infection in humans. In COVID-19, the symptoms appear a little later. While runny nose and sore throat are more prominent in influenza disease, smell and taste problems in COVID-19 are mostly included in the picture of COVID-19 disease. It is also seen that the mortality rate for COVID-19 is higher than for influenza. Sometimes we can say that there is a 3-5 percent mortality rate. There is no such intense mortality rate in influenza. Again, the incidence of pneumonia is higher in COVID-19 patients than in influenza. Therefore, if you ask whether we can distinguish between them with clinical signs and symptoms in a person with upper respiratory tract symptoms during the pandemic period, it is not very possible to be assertive in this regard without testing. Because similar clinical pictures can be seen in both. In COVID-19, about 80 percent of people can be asymptomatic, even without symptoms. In cases where we encounter an infection symptom during the pandemic period, it is important to perform a PCR test in order to differentiate, especially in individuals with risk factors. It is necessary to make a differential diagnosis with a test and to start treatment according to the diagnosis. In the case of influenza, if there is a threatening situation, successful results are obtained if antiviral medications are used. There is a proven antivirus treatment. However, there is no proven antivirus treatment for COVID-19. If there are clinical symptoms when we detect a COVID-19 infection, it is necessary to keep a close watch. In order to apply more serious treatment steps very early, there is a need to differentiate the two with laboratory diagnosis in order to follow the patient closely.

What Are the Points to Be Considered in Order to Go Through a Healthy Winter and to Be Protected from Upper Respiratory Tract Infections?

• Adequate sleep and a balanced diet are the most effective ways to protect the immune system and thus prevent upper respiratory tract infections. Vitamin D is considered to be one of our most important weapons that strengthens immunity and protects it from diseases. However, the level of vitamin D in the body decreases as the possibility of exposure to the sun decreases during the winter months. Therefore, vitamin D supplements should be taken under the supervision of a physician, especially in the winter months. If vitamin D will not be taken in high doses, it can be taken in daily doses (up to 1000-2000 units per day) without the need for vitamin D measurement to meet daily needs. If a person is suspected of having a severe vitamin D deficiency, a higher dose of vitamin D can be given after having a test. If the person has a disease that causes high calcium levels, such as multiple myeloma, sarcoidosis, and hyperparathyroidism, the level of calcium in the blood should also be monitored while treating vitamin D deficiency.
• Vitamin C is one of the most important vitamins for the immune system with its antioxidant effect. This water-soluble vitamin is not stored. It needs to be consumed in sufficient quantities daily. In general, it is abundant in fruits such as oranges, lemons, strawberries, and leafy vegetables such as spinach and cabbage.
• A balanced and healthy diet, especially a protein-rich, helps strengthen the immune system. Protein deficiencies cause lymphocyte deficiency in the body. Lymphocytes are one of the basic cells of the immune system. Meat, milk, eggs, cheese, and legumes are foods with very high protein content, so it is beneficial to consume them in sufficient quantities.
• Exercising regularly is also among the necessities of a healthy life. This habit strengthens heart health, lowers blood pressure, allows us to control body weight, and also strengthens our immune system.
• It should not be forgotten that at least 7 hours of sleep for adults and at least 8-10 hours of sleep for children are very important for a strong immune system.

Under Which Conditions Should You Suspect COVID-19 and Apply to a Health Institution to Have a Test?

Even if there are no symptoms, people in the COVID-19 risk group should have a PCR test, if they have a history of close contact with someone who is known to be positive. The most effective method that shows the current presence, carrying, or infection of this virus is the PCR test. In addition, in cases such as fever, dry cough, muscle-joint pain, runny nose, taste and smell disorder, unexplained fatigue in general condition, weakness, and exhaustion, it is necessary to have a PCR test by getting suspicious.