Is It Covid-19? Recognizing the Most Typical Symptoms

The coronavirus has been complicating our lives for more than two years now. At the beginning, not much was known about the new virus SARS-CoV-2, but today we have enough knowledge about COVID-19. That's why we've summarized the most important facts about COVID-19 symptoms, testing, and prevention in this article.

Updated: 15/07/2022



Symptoms of COVID-19

Every individual is unique, so COVID-19 symptoms can vary among those infected. It also depends on the course of the illness. In most cases, COVID-19 symptoms resemble those of a common flu.

Approximately 20% of those infected with the coronavirus do not experience any symptoms, yet these individuals can still be contagious and spread the infection to others. According to current knowledge, up to 59% of transmissions can come from asymptomatic individuals. For this reason, regular testing and subsequent adherence to mandated isolation are necessary.

The Most Common COVID-19 Symptoms Include:

  • Fever of 37.3°C (99.1°F) or higher
  • Cough
  • Fatigue
  • Difficulty breathing
  • Sore throat, headache, backache, muscle or joint pain
  • Loss of taste or smell
  • Various types of skin rashes, including color changes on the fingers or toes ("COVID toes")
  • Diarrhea
  • Nausea or vomiting
  • Conjunctivitis (pink eye)

Symptoms of the Omicron Variant of the Disease

Omicron primarily affects the upper respiratory tract, so it doesn't usually result in severe lung inflammation and related breathing problems. Other symptoms are quite similar to previous variants, although they are typically milder.

Dr. Angelique Coetzee, Chair of the South African Medical Association, stated in an interview with Reuters that the Omicron mutation most commonly manifests with:

  • Extreme fatigue (1 to 2 days),
  • Headache,
  • and a dry cough.

However, asymptomatic cases are quite common as well.

Symptoms of a More Severe COVID-19:

  • Shortness of breath – a person experiences significant breathing difficulties. They get breathless during normal activities, even when moving around the house or going to the bathroom. It can even lead to a feeling of choking.
  • Loss of appetite
  • Confusion
  • Persistent chest pain or pressure
  • High temperature - over 38°C (100.4°F)

Other Less Common COVID-19 Symptoms Include:

  • Irritability
  • Confusion
  • Reduced level of consciousness – may be associated with seizures
  • Anxiety
  • Depression
  • Sleep disturbances
  • More severe neurological complications – stroke, brain inflammation, delirium, and nerve damage

These difficulties should not be underestimated. If you experience any of the mentioned COVID-19 symptoms (or a combination of them), contact your primary care physician by phone, who will provide you with further guidance.

According to the World Health Organization (WHO), most COVID-19 patients recover relatively easily without the need for hospitalization. In such cases, your primary care physician will establish individual supportive treatment, during which you should maintain isolation, bed rest, and an adequate fluid intake. Approximately 15% of those infected experience a moderately severe course of the illness and require oxygen therapy. Around 5% of those infected reach a critical condition and need intensive medical care.

Based on current experience, a greater number of symptoms in the early days may be associated with a more severe course of COVID-19. Pay particular attention to shortness of breath. If you start to get breathless even during speaking and performing everyday activities, it's a sign that your blood oxygen level is dropping. In case of a dramatic deterioration of your condition, don't wait and contact emergency services.

It's always better to be safe than sorry, and it's crucial to seek medical help promptly.

Post-COVID Syndrome (Long COVID)

Even several months after recovering from COVID-19, some people may experience relatively serious health problems. Professor Nyarie Sithole from the Faculty of Clinical Medicine at the University of Cambridge, stated that about 10% of people who have had COVID-19 suffer from post-COVID syndrome.

Patients may seek medical attention for post-COVID syndrome even 3 or more months after recovering from COVID-19. Based on available data, there hasn't been a proven link between the severity of the illness and persistent health issues. Nyarie Sithole on the contrary argues that they have seen many patients with a mild course of COVID-19 who recovered in a few days, yet subsequently developed post-COVID syndrome.

Although it is generally assumed that older and ill individuals are more susceptible to these problems, post-COVID syndrome also affects young people with good health.

Symptoms of Post-COVID Syndrome

Since the beginning of the pandemic, experts have recorded more than 200 different symptoms of post-COVID syndrome, which also come in waves and change over time. Among the most common symptoms of post-COVID syndrome are:

  • Fatigue (unable to perform even basic household tasks)
  • Brain fog (impaired concentration, memory problems, difficulty finding words, etc.)
  • Shortness of breath (getting breathless even with minimal activity)
  • Chest pain
  • Heart palpitations
  • Migratory joint and muscle pains
  • Abdominal and headache pain
  • Insomnia and worsened sleep

Currently, there is not enough information and scientific studies about post-COVID syndrome to summarize all its effects on human health. However, Nyarie Sithole states that based on studies of related coronaviruses, it can be expected that at least 90% of people with post-COVID syndrome will fully recover within 12 months.

If you suspect you have post-COVID syndrome, visit your primary care physician. They will perform necessary examinations and may refer you for a chest X-ray, routine blood tests, or to a relevant specialist.

What Works for Long COVID / Post-COVID Syndrome?

Initial studies suggest that certain dietary supplements can help in the treatment of post-COVID syndrome, characterized by high and chronic fatigue. Dietary supplements containing vitamins B, C, and D have proven effective.

Mutations of the SARS-CoV-2 Coronavirus

Viruses frequently undergo various mutations caused by errors during replication (multiplication). The more the virus spreads, the more it multiplies, and the likelihood of new mutations arising increases.

The COVID Portal, which is the official information website of the Czech Republic regarding the SARS-CoV-2 coronavirus, states that SARS-CoV-2 creates approximately one to two mutations per month. This means that coronavirus mutations occur less frequently than in other viruses, including the common flu.

The problem lies in the fact that mutations can significantly alter the virus's properties. Essentially, three basic scenarios can occur:

  • Mutation leads to better disease control – this is the ideal situation that can help manage the pandemic. The mutation somehow weakens the virus. For example, it may reduce infectivity or result in milder disease.
  • Mutation leads to worse disease control – now, let's briefly consider the opposite direction of development that many epidemiologists, politicians, economists, and others are concerned about. Due to a mutation, a new variant of the coronavirus can gain strength. It can become more infectious, resistant to vaccines and drugs, or lead to more severe illness.
  • Mutation doesn't change anything in disease control – although mutations affect the virus's genome, the virus's properties do not fundamentally change for humans.

The main ambition of countries is to minimize the risk of new dangerous mutations of the SARS-CoV-2 coronavirus through protective measures. This can be achieved primarily by adhering to protective measures, including the use of respirators, vaccination, maintaining physical distance, improved hand hygiene, isolation, quarantine, and more.

During the COVID-19 pandemic, some variants of the coronavirus succeed in spreading more and persisting in the population through natural selection. Other mutations and variants gradually disappear.

Currently Identified and Documented Variants of the SARS-CoV-2 Coronavirus:

  • Alpha Mutation, previously known as the British variant
  • Beta Mutation, previously known as the South African variant
  • Gamma Mutation, previously known as the Brazilian variant
  • Delta Mutation, previously known as the Indian variant
  • Delta Plus Mutation
  • Omikron Mutation

In a WHO (World Health Organization) study, experts focused on comparing the rate of spread of SARS-CoV virus variants. Compared to the original "Wuhan" coronavirus, they spread as follows:

  • Alpha (B.1.1.7) spreads 29% faster
  • Beta (B.1.351) spreads 25% faster
  • Gamma (P.1) spreads 38% faster
  • Delta (B.1.671.2) spreads 97% faster
  • Omikron (B.1.1.529) spreads 70 times faster than Delta but is 91% less deadly
  • Centaurus BA.2.76

According to evolutionary biologist Tom Wenseleers from the Catholic University of Leuven in Belgium, the new Omikron mutation (B.1.1.529) is even more contagious. Current data show that Omikron spreads three to six times faster than Delta.

Extremely Contagious Omikron Mutation Has Swept the World

Scientists first detected the new Omikron mutation (B.1.1.529) in the Republic of South Africa from samples taken on November 11, 2021. Over the following weeks, the extremely contagious variant of the coronavirus spread worldwide and gradually displaced the previously dominant Delta mutation.

The Omikron wave caused the number of COVID-19 cases to skyrocket. For example, on January 26, 2022, France had a daily increase of over 360,000 cases. A similar situation occurred in the Czech Republic, where on January 26, 2022, over 56,000 people were newly diagnosed with COVID-19.

Fortunately, available data indicate that Omikron generally has a milder course. You can notice this in the lower increase in the number of hospitalizations and deaths.

However, Omikron should definitely not be underestimated. It is still a serious illness that can cause extensive health problems and, in some cases, even lead to death.

Omicron Subvariants BA.4 and BA.5 Are the Fastest-Spreading Covid-19 Variants

Two new Omicron subvariants known as BA.4 and BA.5 are gaining worldwide prominence. How contagious are they, and what do we know about them?

Omicron subvariants BA.4 and BA.5 evade antibody responses in individuals who have had prior Covid-19 infections as well as those who have been fully vaccinated, including with booster shots. According to new research published on Wednesday in the New England Journal of Medicine, the levels of neutralizing antibodies induced by previous infection or vaccination against subvariants BA.4 and BA.5 are several times lower compared to the original coronavirus. This means that BA.4 and BA.5 variants are more likely to escape antibodies in the blood of fully vaccinated adults compared to other Omicron subvariants.

BA.4 and BA.5 are currently the fastest-spreading variants, and it is expected that in the coming weeks, they will dominate the transmission of Covid-19 in the United States, the United Kingdom, and the rest of Europe, as reported by the European Centre for Disease Prevention and Control.

What Sets These Subvariants Apart?

  • More contagious than previous variants
  • Resistant to acquired immunity from Omicron infections
  • According to research from Ohio State University, patients who had previously contracted the Delta variant have better immunity against subvariants BA.4 and BA.5. However, the time elapsed since Delta variant infection is crucial.
  • Recent data suggest that reinfection with both of these subvariants is common, even after recent infection with subvariant BA.2.

Symptoms of Subvariants BA.4 and BA.5

Experts say it's too early to determine whether cases associated with these subvariants have specific symptoms or lead to long-lasting symptoms.According to experts, most symptoms of recent subvariants are similar to other COVID strains, including stuffy nose, body aches, sore throat, sneezing, headaches, cough, fatigue, and more.

Presence of the L452R Mutation, Indicating the Spread of Subvariants BA.4 or BA.5 in the Czech Republic

The National Reference Laboratory (NRL) for influenza and non-influenza viral respiratory diseases SZÚ reports a significant shift compared to the previous week in the representation of the specific L452R mutation. This is an inter-week percentage jump from approximately 8% of samples tested using discriminative PCR (8.27%) in the week of June 6th to 12th to over 53% (53.2%) in the week of June 13th to 19th. This shift is most likely attributed to the increase in Omicron subvariants BA.4/BA.5, although it has not yet been confirmed by whole-genome sequencing.

Testing in the Czech Republic has seen a massive slowdown, with tests no longer being mandatory or currently required for travel to some countries. Laboratories are also conducting discriminative PCR tests to a lesser extent because this examination is covered by health insurance only upon a doctor's request.

People should be aware that they can get infected again and should not succumb to a false sense of security. Several cases of reinfection with subvariants BA.4/BA.5 and reinfections after prior BA.2 variant infections have occurred in the world in recent months.

Spread of Subvariants BA.4/BA.5 Worldwide

The first occurrences of these variants were recorded in South Africa, but in recent weeks, the numbers have also started to rise in the USA, where significant prevalence is expected by the end of the summer. These variants currently dominate in countries like Portugal (75.3%), the United Kingdom (50%), and Israel (41.8% - BA.4).

Risk of Reinfection After Recovering from Omicron vs. Delta Variants

It appears that a genetic feature known as the "delta mutation" allows the BA.2.12.1 subvariant to resist previous immunity from vaccination or prior illness, especially if you were infected during the Omicron wave.

This is because the original Omicron strain that swept the world didn't have this mutation. This genetic change is also present in the related Omicron subvariants BA.4 and BA.5.

This genetic change is bad news for people who caught the original Omicron and thought it was unlikely they'd get COVID-19 again anytime soon. Even though most people don't know with certainty which variant caused their illness, the original Omicron triggered a massive wave of cases at the end of last year and the beginning of this year.

Laboratory data suggests that previous infection with the original Omicron is not very effective in preventing reinfection with new mutants, although the actual risk of reinfection, regardless of the variant, is unique to each individual and situation.

Those who have recovered from Delta with a more severe course may have an advantage. Antibodies generated by the Delta variant seem to be more effective in neutralizing new mutants than in patients who caught the original Omicron. However, the level of protection provided by Delta infection partly depends on how long ago a person was sick because immunity weakens over time.

Centaurus Subvariant

A subvariant known as Centaurus, originating from India, has begun to spread and has been detected in several countries, including the Czech Republic. Everything suggests that it could be the most highly contagious version of COVID-19 yet, potentially bringing another massive wave of the pandemic in the autumn. What experts find alarming, though, is that it appears that there is insufficient immunity to Centaurus even after recovering from the illness, including after Omicron infection, particularly the BA.1 variant. However, the extent of this resistance is not yet known.

Mandatory Masking Remains in Some Places

The year 2022 has seen a return to "normal." Although some countries still require masks in certain places (such as Austria), many other countries have lifted all Covid restrictions.

Increasingly, experts are leaning toward the belief that SARS-CoV-2 coronavirus might stay with us "forever," so we need to learn to live with it. If we don't want to unnecessarily risk our health, we should continue to use the best possible protection against infection – FFP2 masks and vaccination.

FFP2 Masks Provide Approximately Twice the Protection Against Omicron Compared to Delta

The problem with Omicron isn't just its higher contagiousness. The WHO (World Health Organization) states that the new mutation may make reinfection easier. This means that even antibodies from a previous Covid-19 infection will likely not help you defend against Omicron.

Current vaccines still protect against severe cases, but even the WHO acknowledges that even fully vaccinated individuals can get infected, and this happens much more frequently than with previous mutations.

However, Omicron also brought an interesting surprise. A study from the prestigious Max Planck Institute showed that properly worn FFP2 respirators protect you from Omicron approximately twice as effectively as from Delta. Yet, the Omicron mutation is roughly three to six times more contagious.

According to research, a person with Omicron can be in close proximity to an uninfected individual (less than 1 meter) for up to 20 minutes, and if both individuals are wearing well-fitting FFP2 respirators, the maximum risk of infection is less than 1 per mil. This means that on average, less than 1 person out of 2,000 will get infected.

Surprisingly, the respirator still provides good protection even if it doesn't seal 100%. If you have it worn over your mouth and nose but it doesn't fit perfectly on your face, the probability of infection increases by only about 4% for Delta and just under 3% for Omicron.

The study once again confirmed that FFP2 respirators are among the most effective protections against the coronavirus. Interestingly, they work even better against the extremely contagious Omicron than against Delta.

A similar situation was revealed in a study involving masks. If both sides wear masks, the maximum risk of infection is roughly 10% for Delta and just under 8% for Omicron. The test was conducted under the same conditions as the one with respirators.

Scientists attribute this fact to Omicron's greater presence in the upper respiratory tract. It then spreads in larger droplets than previous mutations of the SARS-CoV-2 coronavirus, which primarily develop inflammation in the lungs. And larger respirator particles capture better.

Covid Incubation Period

The incubation period of the coronavirus ranges from 1 to 14 days. However, symptoms most commonly appear within 5 to 6 days after contact with an infected person. Omicron, compared to Delta and other mutations, has a shorter incubation period, estimated at 3 days.

Who Belongs to the Risk Group?

The most at-risk groups include people aged 60 and older, those with chronic illnesses, and individuals with weakened immune systems. Severe cases of COVID-19 often occur in these patients. Serious respiratory problems requiring intensive care support, such as ventilators, are more common in people with high blood pressure, heart and lung problems, diabetes, obesity, or cancer.

However, everyone should be cautious because severe illness or death is not limited to the risk group. Additionally, the Omicron mutation is more likely to affect children and younger adults who previously had relatively good defenses against previous coronavirus variants.

How Does COVID-19 Manifest in Children?

Symptoms of COVID-19 in children are mostly similar to those in adults. The most common symptoms include fever, weakness, muscle pain, cough, sore throat, and digestive problems like nausea, vomiting, abdominal pain, and diarrhea.

Approximately 90% of children up to 18 years old, however, experience mild cases of COVID-19. In fact, children often exhibit no symptoms at all, so coronavirus infection is only discovered after a positive test result in one of the parents.

According to the WHO, the risk of severe illness and hospitalization primarily affects children dealing with high blood pressure, heart and lung issues, asthma, diabetes, obesity, cancer, neurological, or developmental conditions.

Risk of COVID-19 in Pregnancy

During pregnancy, certain parts of the immune system are suppressed to increase tolerance for the developing fetus. This means that pregnant women are particularly at risk for illnesses, including COVID-19. Recent studies on the impact of COVID-19 are alarming, as they indicate an increased risk of premature birth (14.4%) and neurodevelopmental problems in infants (by 80%).

A study conducted by researchers at University College London reveals that pregnant women who contract COVID-19 during the first trimester have a higher likelihood of experiencing a premature miscarriage. Another study led by a group at Harvard Medical School found that infants born to mothers who had COVID-19 during pregnancy are more likely (by 80%) to receive a neurodevelopmental diagnosis within the first 12 months after birth (motor function problems and speech impairments). The good news? Vaccination of pregnant women can help reduce many risks associated with SARS-CoV-2 infection during pregnancy.

Benefits and Risks of COVID-19 Vaccination During Pregnancy

Although initially, vaccination of pregnant women was not recommended in the first trimester, we now have reasonably solid data on the safety of vaccination during pregnancy. Everything suggests that COVID-19 vaccination significantly reduces risks for both the mother and the child. Firstly, the risk of developing COVID-19 is lower in vaccinated mothers. The likelihood of stillbirth is also significantly reduced in vaccinated mothers - by 15% compared to unvaccinated mothers. The rate of adverse effects in vaccinated mothers - including the risk of miscarriage.

Vaccination of pregnant women also protects the baby against COVID-19. Antibodies from the mother's body pass through the placenta to the fetus, providing immunity against SARS-CoV-2. These elevated antibody levels can persist for up to 6 months after birth. For infants born to vaccinated mothers, the likelihood of requiring hospitalization due to COVID-19 is much lower and decreases by up to 80% for ICU admission. If you want to maximize protection for your child, the second dose should be administered after the 20th week of pregnancy, ensuring the highest level of antibodies for the baby.

How to Distinguish COVID-19 from Allergies

Coughing, stuffy nose, watery eyes, nasal itching, throat irritation, loss of smell, and, in some cases, headaches, fatigue, and various skin rashes. As you may suspect, distinguishing between a COVID-19 infection and allergy symptoms can be quite challenging.

What should alert you that it's not just a severe allergic reaction? Pay attention, especially, to high temperatures, loss of smell, and joint pains. It's more challenging to differentiate with the Delta variant, which often doesn't include the loss of smell and taste among its symptoms.

If you're not 100% sure, it's better to take a COVID-19 test. It's always better to verify your health status rather than neglect prevention and potentially endanger yourself and others in your surroundings.

COVID-19 Testing Options

Until the entire population is fully vaccinated, regular testing will continue to be one of the most effective tools in the fight against COVID-19. It helps to detect infectious individuals early and prevent the uncontrolled spread of the SARS-CoV-2 virus.

Currently, there are several types of COVID-19 tests available. Each method is suitable for different situations and operates on different principles.

Antigen Tests

This type of test detects a protein specific to the SARS-CoV-2 coronavirus in the sample. The sample is collected using a special swab from the beginning of the nose, so the sample collection is not uncomfortable and can be performed even by non-medical personnel. The rapid test result is displayed within 15-30 minutes. Antigen tests are most effective in the early stages of infection when there is a high viral load in the body.

PCR Tests

This is the most reliable and sensitive method that detects the presence of viral genetic information (RNA) in the sample. However, it requires cooperation with a specialized laboratory, and the evaluation usually takes several hours. Another disadvantage is the high cost of the test, which is why it is not suitable for mass testing. 

Antibody Tests

The drawback is that they do not capture the very beginning of the disease when a person is most infectious. As the name suggests, a blood sample test reveals the presence of antibodies against the SARS-CoV-2 virus. Antibody tests are suitable for individuals recovering from COVID-19 and for those who have already had the disease and want to verify the level of "protective" antibodies in their blood.

How to Protect Yourself from Coronavirus?

There has been a prevailing opinion in society that only widespread vaccination and achieving herd immunity can end the COVID-19 pandemic. That's why COVID-19 vaccination has become the preferred form of protection against the disease.

In addition, it's worth following basic methods to protect yourself from SARS-CoV-2 infection. These include primarily wearing certified FFP2 respirators and masks, which are even more effective against the highly contagious Omicron variant.

You can reduce the risk of SARS-CoV-2 infection by following simple preventive measures:

  • Maintain physical distance from others - ideally 2 meters or more.
  • Avoid crowded places, poorly ventilated areas, and prolonged contact with people indoors.
  • Regularly clean surfaces with standard disinfectants or ozone generators.
  • Avoid touching surfaces, especially in public places and healthcare facilities.
  • Wash your hands frequently and thoroughly. You can also use alcohol-based hand sanitizers.
  • When coughing, cover your nose and mouth with a bent elbow or tissue. Dispose of used tissues immediately in a closed bin and wash or sanitize your hands.
  • Adhere to current epidemic prevention measures mandated by the government.

Vaccine Effectiveness Against the Omicron Variant

Data from thousands of studies show that the effectiveness of the vaccine against severe COVID-19 decreases for Omicron compared to pre-Omicron variants one month after completing the vaccination. The vaccine is most effective between 1 month and 6 months after vaccination completion. The effectiveness of the vaccine against symptomatic infection is also lower for Omicron compared to previous variants. So, how does it provide protection?

One of the vaccine effectiveness studies for the Omicron variant demonstrates that the vaccine's effectiveness increases with each additional dose and with the fourth dose, it was 49% effective against infection, 69% (61% to 76%) against symptomatic infection, and 86% (81% to 90%) against severe disease.

Is Getting a Fourth Dose of the Vaccine Against Omicron Worth It?

Israel was the first country to administer a fourth dose in January on a large scale (Pfizer-BioNTech) to people aged 60 and older, as well as to highly at-risk patients and healthcare workers (those with more than four months elapsed since the third dose).

According to a study published in The New England Journal of Medicine based on a sample of 1.2 million people aged 60 and older, the level of protection against COVID-19 one month after the fourth dose was 3.5 times higher than among those who received only three doses.

Almost No or Little Benefit of a Fourth Dose for Younger People

For younger individuals, the immune response was only slightly higher than in those who received only three doses. It is assumed that there should be a longer interval between boosters for younger people.

When and Where to Get the Fourth Dose of the COVID-19 Vaccine?

Vaccination with the fourth dose has already started (July 18). Currently, it is recommended only for people aged 60+, chronically ill individuals, and other high-risk groups. Gradually, it is expected that younger people will also be vaccinated.

Vaccination for high-risk groups is currently available without reservations, and it can be done at your general practitioner's office or at vaccination centers. 

Brief Overview of Available COVID-19 Vaccines

Since the beginning of the COVID-19 pandemic caused by the SARS-CoV-2 virus, scientists worldwide have been working to develop an effective and safe vaccine. Thanks to their exceptional efforts, we now have several vaccine options available. To ensure maximum safety, only registered vaccines for the EU territory can be administered in the Czech Republic.

Currently, these 4 vaccines are in use:

  • COMIRNATY by Pfizer/BioNTech
  • SPIKEVAX by Moderna
  • VAXZEVRIA by AstraZeneca
  • JANSSEN by Janssen Pharmaceutica (Johnson & Johnson)

Side Effects of COVID-19 Vaccines

Similar to other vaccinations, some individuals may experience temporary reactions after receiving the COVID-19 vaccine, which generally subside within a few days.

Experts have been closely monitoring adverse reactions since the beginning of vaccine clinical evaluations. This means that you do not need to be overly concerned about approved vaccines. The likelihood of severe adverse effects is minimal.

The most common short-term reactions after COVID-19 vaccination include:

  • Pain and swelling at the injection site
  • Fatigue
  • Headache
  • Fever
  • Chills
  • Muscle and joint pain
  • Nausea
  • Swelling and tenderness of the armpit lymph nodes

Such reactions are common with virtually all vaccines, so it's nothing specific to COVID-19 vaccination. 

What to Do If You Suspect COVID-19?

Take an antigen test. A physician can also provide you with a test request form for a collection center. Always call the clinic first; never visit the clinic if you suspect COVID-19 unless instructed by a doctor. 

Do I Need to Quarantine If I've Had a Risky Contact?

No. Quarantines were lifted in February. However, act responsibly. It is recommended to wear a respirator in the first few days and, if you experience any symptoms, consider taking an antigen test. It's also advisable to avoid contact with high-risk groups in the following days.

I've Tested Positive for COVID, What Now?

If you have received a positive result on an antigen or PCR test, inform your doctor, as this marks the beginning of isolation, which lasts a minimum of 7 days. You can end it if you remain symptom-free for at least two days before the end of the isolation period. 

Where Can I Find More Information About COVID-19?

There is a wealth of information about coronavirus on the internet. Unfortunately, the quality and accuracy of articles vary. Additionally, the situation surrounding COVID-19 is constantly evolving, so some information may not be up-to-date. 

Always seek information from credible sources – websites like the Ministry of Health, the Covid Portal, the World Health Organization, the State Institute for Drug Control, and others.

Frequently Asked Questions

What are the BA.4 and BA.5 variants?

These are two similar subvariants (subtypes) of the omicron strain of Covid-19.

What are the symptoms of the BA.4/BA.5 subvariant?

So far, no distinct symptoms different from previous variants of Covid-19 have been identified. Common symptoms include a stuffy nose, body aches, sore throat, sneezing, headaches, cough, and fatigue.

I had omicron before. Can I get infected with one of the omicron subvariants?

Yes. Unfortunately, available data suggest that individuals who had this illness during the omicron wave are even more susceptible to infection with the BA.4/BA.5 subvariants.

I had delta before. Can I get infected with one of the omicron subvariants?

Currently, it is believed that individuals who were previously infected with the delta variant are better protected against infection with the BA.4/BA.5 subvariants. This is based on recent research conducted in the USA. COVID-19 patients in their intensive care units with delta infections had antibodies that more effectively neutralized the new mutants.

I am vaccinated. Do I still need to fear BA.4/BA.5 infection?

According to currently available information, it is unfortunately possible to get infected with these subvariants even after vaccination, including booster doses, and even after a previous illness.

However, it's important to note that vaccination remains highly effective in protecting against severe illness and hospitalization.


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Lukáš Konečný, Strategy and business development, nanoSPACE
Lukáš Konečný has been active in the nano field since 2015. He graduated from the University of Economics and Business and has long been involved in digital marketing, digitisation and automation of advertising for technology companies and online projects. At nanoSPACE, Lukáš has been in charge of strategy and business development since May 2020.