New variants of COVID-19 and influenza emerging in Poland are bringing a range of atypical symptoms and posing challenges to public health. Read on to learn what to expect in the 2026 season and how to protect yourself from the wave of infections.
Discover the latest symptoms and variants of COVID-19 and influenza in Poland. Learn about symptoms, forecasts, and ways to protect yourself from the coming wave of infections in 2026.
Table of Contents
- The New Wave of COVID-19 and Influenza Infections in 2026 – What to Expect?
- Most Common and Unusual Symptoms of New COVID-19 Variants
- The “K Variant” of Influenza – Symptoms and Health Risks
- How to Distinguish COVID-19 from Influenza? Key Symptoms
- Are We Facing Another Pandemic? Experts and Forecasts
- What to Do If You Experience New Symptoms?
The New Wave of COVID-19 and Influenza Infections in 2026 – What to Expect?
Public health experts predict that 2026 will bring another marked wave of infections from both COVID‑19 and influenza, especially in the autumn-winter season, when respiratory infections traditionally surge. The cause is not solely the virus itself, but a combination of overlapping factors: weakened population immunity months after the last vaccinations or infections, changes in social behavior (return to offices, increased travel, mass events), and the emergence of new variants and viral sublineages that better “escape” immune response. In practice, this means that in 2026 we may see a so-called double wave – a simultaneous rise in seasonal influenza and COVID‑19 cases, with periodic “peaks” of illness in different regions of Poland depending on weather, mobility, and local vaccination rates. Hospitals, clinics, and emergency medical systems may be under increased pressure again, especially as many patients now present with chronic conditions previously diagnosed or worsened during the pandemic, raising the risk of severe infection. In the new wave, the so-called syndemic effect is crucial – the concurrence of several diseases and risk factors at once: viral infections, cardiac conditions, diabetes, obesity, chronic obstructive pulmonary disease, or weakened immunity due to stress and lifestyle. Increasingly important is the “immunological gap” in some children and adolescents, who for years of restrictions and remote learning had less exposure to typical seasonal viruses, making their bodies potentially react more strongly to serious infections. Additionally, as epidemiological restrictions have eased, many people have abandoned mask-wearing in crowded spaces, wash or disinfect their hands less often in public, and more frequently ignore mild infection symptoms at work or school, “powering through illness”—all of which favors faster and broader viral spread. In 2026, expect the infection season to start earlier than usual and possibly last longer, with several overlapping waves depending on dominant variants at any time.
The new infection wave, however, will not look identical to those from the early years of the pandemic—patient profiles, symptoms, and the dynamics of transmission are all changing with the evolution of SARS‑CoV‑2 and circulating influenza strains (A/H1N1, A/H3N2, or B). Projections indicate that 2026 may see COVID‑19 variants better adapted to infecting previously vaccinated or infected individuals, but also more “focused” on upper respiratory tracts than lungs, lowering mortality but increasing contagiousness; a similar trend holds for influenza, where small “antigenic drifts” in the viral genome mean that immunity from previous seasons may not fully protect, though it can mitigate severity. The number of coinfections—simultaneous COVID‑19 and influenza infection—is also likely to rise, typically associated with more severe illness, longer fever, and higher risk of pneumonia and cardiovascular complications. The most vulnerable remain seniors, chronically ill, pregnant women, and immunosuppressed patients (such as after chemotherapy, transplants, immunosuppressive therapy); however, recent data reveals that young, actively working people under stress and with undiagnosed conditions may also experience severe disease. This means that by 2026, society can’t simply be split into the “100% safe young” and “endangered seniors”—risk is more evenly spread, though its level depends on individual health and lifestyle. From the healthcare system and daily life perspective in Poland, more frequent infection outbreaks are expected in workplaces, schools, kindergartens, and universities, along with recurring discussions about temporary mask mandates in public transit during peak season. Occasional overloading of ERs and night clinics is possible, particularly in areas with low access to primary care or low medical staffing. Therefore, telemedicine, quick online consultations, and home antigen tests for COVID‑19 and influenza will become increasingly important for timely isolation and antiviral treatment decisions. On an individual level, the new infection wave in 2026 means more careful monitoring of your health, and treating even a “simple cold” seriously, as distinguishing mild infection from early COVID‑19 or influenza is difficult without testing. Expect more sick leave days, switches to hybrid work in companies, and temporary suspension of classes in schools dealing with outbreaks. Experts stress that while completely avoiding viral contact in 2026 will be nearly impossible, the scale and impact of the wave will largely depend on vaccination rates against COVID‑19 and influenza, adherence to basic hygiene, a “stay home when sick” culture, and institutions’ readiness to act on local rises, without resorting to broad, nationwide lockdowns.
Most Common and Unusual Symptoms of New COVID-19 Variants
New SARS-CoV-2 variants observed in 2026/2027 still predominantly attack the respiratory tract, but increasingly present clinically like typical colds or influenza, making self-diagnosis harder. The most common symptoms still include fever or low-grade fever—nowadays, usually lower (37.5–38.2°C), coming in waves and persisting for days without distinct symptoms. Also typical are sore throat, hoarseness, and the sensation of a “scratchy” throat, which in recent viral sublines may be the first and main symptom, often mistaken for air conditioning or dry air. A dry or productive cough remains characteristic, though it’s often milder than in earlier waves and thus more easily ignored. Infected individuals frequently report increasing fatigue and general malaise—a feeling that “the body is heavy,” trouble concentrating, and slowed reactions, leading to reduced work and study efficiency even without high fever. Typical symptoms also include headache (often pulsating, affecting the forehead and eye region), muscle/joint pain, and alternating feelings of heat and chills. Runny or stuffy nose, once less associated with COVID-19, now appear very often—secretions may be watery or thick, with accompanying congestion resembling classic viral infections in children. More patients also report watery eyes, burning conjunctiva, and sensitivity to light, suggesting viral conjunctivitis. Unlike in 2020–2021, complete loss of smell and taste is observed much less frequently, but partial, temporary disturbances still occur: taste seems “flat,” and smells are less intense, often noted only when eating strongly flavored foods. For many, infection looks almost identical to a “normal cold”: mild sore throat, runny nose, occasional cough, and slight weakness. This “mild face” of new variants leads to unintentional spreading—the infected go to work, school, and university, thinking the symptoms are just fatigue or weather change. Yet, for some—especially the unvaccinated, chronically ill, or immunosuppressed—symptoms may suddenly worsen: breathing difficulties, chest pain, rapidly increasing shortness of breath, or a distinct sense of “no air” even with minor activity. These require urgent medical attention as they may signal pneumonia or thromboembolic complications. In the 2026 season, the timing of symptom onset is also variable—sometimes within 1–2 days after exposure and sometimes only after 4–5 days, complicating infection tracing. Additionally, symptom courses tend to be “wavelike”: mild in the first 2–3 days, followed by apparent improvement, then a resurgence of cough, fatigue, or fever after several days.
New COVID-19 variants are also causing a host of unusual symptoms, rarely linked with the infection just a few years ago but now increasingly described by doctors and patients alike. Gastrointestinal complaints—diarrhea, nausea, “tightness” in the stomach, abdominal pain, or lack of appetite—are ever more common. These digestive problems can be the first or even main symptom in some, with respiratory symptoms developing later or remaining mild. Successive COVID-19 waves also bring non-specific neurological symptoms: sudden severe headaches, dizziness, a feeling of “brain fog”, concentration problems, word-finding difficulties, or momentary “spacing out” during conversation. Worrying examples include sudden weakness in one limb, balance issues, slurred speech, or double vision—symptoms resembling stroke, requiring urgent diagnosis and not to be dismissed as merely “strong COVID.” Some patients also experience chest pain, heart palpitations, a feeling of “skipped” heart rhythms, or sudden weakness with cold sweats, pointing to possible cardiovascular involvement. Younger, otherwise healthy people are experiencing episodes of tachycardia and unstable blood pressure that may last for weeks post-infection; though often attributed to stress, recent infections should prompt a medical consult. More and more cases involve skin symptoms: maculopapular rashes, itchy pimples, urticaria, and “COVID toes”—reddened, painful, or itchy lesions on toes or fingers resembling frostbite. There are also reports of sudden skin deterioration, flares of acne, or post-infection psoriasis, likely reflecting inflammatory immune burden. Some, especially women, report temporary menstrual disturbances during or shortly after infection—changes in cycle length, heavier bleeding, or intercycle spotting. Psychologically, new COVID-19 variants are often linked with worsening mood, anxiety, irritability, tearfulness, sleep problems, and sensations of being “detached from reality.” Some describe feeling as if “the body can’t keep up with the head”—extreme fatigue, while thoughts race restlessly. Such symptoms may be dismissed as stress, but their sudden onset after exposure or during local outbreaks should prompt testing. Doctors also note altered presentations in the vaccinated and those previously infected: illness often starts mildly—with runny nose and sore throat—but atypical symptoms, like concentration troubles, palpitations, worsening fatigue, or persistent headaches, may only appear days later as classic symptoms subside. This means that even with a “mild” start, any sudden change in complaint should not be ignored, and any alarming or new symptom should be discussed with a doctor, especially in those at risk of severe COVID-19.
The “K Variant” of Influenza – Symptoms and Health Risks
In 2026, epidemiological experts are calling increased attention to the “K variant” of influenza—a new viral lineage with altered clinical and epidemiological characteristics, likely to play a significant role in the coming autumn-winter season. Though “K variant” is a simplification used by media and popular science, it denotes a set of influenza mutations observed in several European countries, potentially including Poland. The key feature of this variant is its heightened contagion in closed environments—like schools, open-space offices, or factories—fueling rapid outbreaks in a short time. Unlike classical seasonal flu, the “K variant” often produces a mélange of influenza, COVID‑19, and common cold symptoms, complicating at-home disease identification. Patients report a very sudden onset, often within hours: chills, severe malaise, muscle and joint pain, and rising fever up to 39–40°C—however, in some (especially the elderly), it may stay as low-grade fever, masking a severe course. Symptoms include intense sore throat, dry irritating cough (sometimes turning productive later), and a characteristic burning pain of the back, thighs, and calves—described as “like strong poisoning” or “bad muscle aches without exercise.” Infections with the “K variant” often also feature severe headache, sometimes with light and noise sensitivity, signaling nervous system involvement. Notably, gastrointestinal symptoms—diarrhea, nausea, rarely vomiting—are much more common than in classic flu, previously more associated with some COVID‑19 variants. Many patients suffer profound fatigue and “brain fog” (concentration trouble, slowed thinking, trouble doing daily tasks), which may linger for weeks after acute illness, resembling long COVID. Upper respiratory symptoms include watery runny nose, congestion, hoarseness, and a dry, irritated throat; some also struggle with “burning” eyes and tearing, initially mistaken for allergy. The incubation for the “K variant” is short—first symptoms may show as early as 24–48 hours after contact, promoting rapid household and workplace spread. Infectiousness generally lasts from one day before symptoms to about 5–7 days, though immunosuppressed patients may shed virus longer. This means someone feeling only mildly unwell but infected can unwittingly spread it to many in a bus, office, or university class before developing full disease.
As for health risks, the “K variant” is concerning mainly due to a higher risk of complications in certain groups and possible compounding by concurrent COVID‑19 infection (coinfection). Highest risk of severe illness remains among those over 60–65, people with chronic diseases (diabetes, COPD, asthma, heart failure, hypertension, obesity, kidney or liver diseases), immunosuppressed (under cancer treatment, transplant, autoimmune disease), and pregnant women. For these groups, the “K variant” is more likely to cause pneumonia, exacerbation of cardiac conditions, respiratory failure requiring hospitalization, and occasionally intensive care. However, young, healthy, active people may suffer serious complications if they ignore initial symptoms and “soldier on” instead of resting and staying home. Potential complications include viral or bacterial pneumonia, myocarditis and pericarditis (with chest pain, palpitations, sudden shortness of breath), middle ear infection, sinusitis, and worsening of chronic respiratory illnesses. More neurological symptoms are being reported: severe, persistent headaches, transient balance issues, memory problems, dizziness, rarely neurological emergencies requiring specialist care. A major risk is possible simultaneous infection with the “K variant” and a new SARS‑CoV‑2 version, which burdens the respiratory and immune systems, leading to more severe courses, longer recovery, and increased hospitalization rates. For healthcare, this means more patients needing oxygen therapy, more admissions to internal medicine and pulmonary wards, and a need to differentiate if shortness of breath is from flu, COVID‑19, or both. For individuals, recognizing warning signs—sudden breathlessness, chest pain, persistent high fever despite fever reducers, confusion, seizures, blue lips or face—means seeking urgent medical help or calling emergency services. Another “K variant” issue is post-infectious fatigue, impacting work or study, and possible spikes in anxiety or depression among susceptible persons, confirming its physical and mental impact. Public health analyses suggest partial escape from post-vaccination or prior flu-acquired immunity, possibly raising infection rates even in those who usually weathered flu seasons mildly; however, updated seasonal vaccines are tailored to circulating variants and remain one of the most effective ways to prevent the worst “K variant” complications.
How to Distinguish COVID-19 from Influenza? Key Symptoms
Distinguishing COVID-19 from influenza in the 2026/2027 season is especially difficult, as new SARS‑CoV‑2 and “K variant” flu strains produce highly similar symptoms. However, there are some characteristic differences highlighted by physicians and epidemiologists. Influenza, including the new variant, usually starts suddenly—one day you may feel fine, and the next you wake up with high fever (often 38–40°C), chills, malaise, and intense muscle and joint pain. Runny nose is rarely a chief early flu symptom—instead, strong general symptoms dominate: body aches, a feeling of being “broken,” sudden weakness, making even getting up from bed difficult. In contrast, new COVID‑19 versions often start more mildly and insidiously: people report a “scratchy” throat, mild cough or runny nose, moderate fever or low-grade fever, and gradually increasing fatigue—easily mistaken for a cold. Note when symptoms start after exposure: flu’s incubation is shorter (usually 1–4 days), COVID‑19 appears more after 3–7 days, although both show exceptions. Peak flu symptoms usually occur early, often around day 2 or 3, while COVID‑19 deterioration may come more slowly, around days 5–7. Lasting fatigue, weakness, and reduced fitness—lingering for weeks—remains more typical of COVID‑19 than classic flu. Simultaneously, the new “K variant” flu more often causes throat symptoms (severe pain, burning, hoarseness), blurring the distinction between flu and coronavirus.
Some specific symptoms help differentiate the two. In prior COVID‑19 waves, loss of smell and taste was typical—now less frequent, but sudden, noticeable impairment of these senses is still more likely COVID‑19 than flu. New COVID‑19 variants also commonly involve dry, troublesome cough (sometimes later productive), chest tightness, exertional or resting breathlessness, persistent headaches, and “brain fog”—concentration problems, slow thinking, “unreal” sensations. Meanwhile, the “K variant” of flu more frequently causes gastrointestinal issues: nausea, vomiting, diarrhea, cramps, less common in classic flu—yet also seen in COVID‑19, especially in children. Classic flu less often produces persistent runny nose—this is more commonly associated with colds or mild COVID‑19. If severe muscle and joint pain, extreme malaise and chills, and rapid health deterioration within a few hours dominate, doctors lean towards influenza. Remain alert to sudden breathlessness, chest pain, confusion, balance issues, or severe, unusual headaches—these may point to severe COVID‑19 or flu complications (e.g., pneumonia, myocarditis, stroke), requiring urgent medical attention no matter the underlying infection. At home, without medical exams and tests, it’s usually impossible to differentiate the two with certainty. Therefore, if symptoms persist, fever worsens, overall condition declines, cough intensifies, or if you’re at risk (senior citizens, pregnant women, those with chronic illnesses), testing for SARS‑CoV‑2 and influenza is essential to confirm diagnosis and support treatment—including antivirals. The only safe strategy is to assume that any strong flu-like syndrome in 2026 could be either COVID‑19 or influenza, and responsible behavior (isolation, mask-wearing around others, prompt medical consult) reduces spread risk regardless of exact cause.
Are We Facing Another Pandemic? Experts and Forecasts
With the emergence of new SARS-CoV-2 and influenza variants—such as the “K variant”—the question returns whether 2026 might bring another full-scale pandemic like 2020–2021. Public health experts stress that a pandemic is not just a large number of cases, but mainly uncontrolled global spread of a new or significantly changed pathogen, against which the population has very little immunity. Current WHO, ECDC, and national (including Poland’s National Institute of Public Health) forecasts suggest more infection waves than a “new beginning” pandemic, but the unpredictable evolution of respiratory viruses requires constant readiness. Researchers state SARS-CoV-2 is now in endemic circulation, like flu—meaning it’s here to stay, causing periodic surges especially in autumn and winter. At the same time, new variants may show higher transmitability, partial escape from vaccine or post-infection immunity, and potential for coinfection (with flu, RSV, adenoviruses), making the 2026/2027 season potentially the most challenging since the pandemic began. Epidemiologists foresee a “long, undulating epidemic” scenario, rather than a single explosive pandemic event, with severity depending on vaccination rates, hygiene adherence, and healthcare system efficiency.
Forecast models consider several vital risk factors for a new pandemic: viral mutation rates, global mobility, population immunity levels, and medical systems’ response abilities. For SARS-CoV-2 and influenza, this means monitoring so-called Variants of Concern (VOC)—those showing significant changes in transmission, virulence, or immune escape. Currently dominant Polish and European variants are generally more contagious but often cause milder disease in the vaccinated or previously infected—lowering mass hospitalization risk but promoting silent transmission. In contrast, the 2020 pandemic was driven by the “newness” of the virus to human immunity, with no vaccines or therapies available. Now, with adapted vaccines and a better grasp of disease mechanisms, it is far less likely that draconian measures like full lockdowns will return. Experts instead predict occasional local restrictions—e.g., mask requirements in hospitals, care homes, or public transport during peaks—and stronger vaccination drives for at-risk groups ahead of autumn-winter. Also critical is the prospect of “twindemics” or even “triple-demics”—simultaneous surges in COVID-19, flu, and other respiratory viruses—which may overload hospitals even without a new pandemic declaration. A red flag for epidemiologists would be a new variant—SARS-CoV-2 or flu—combining high contagion, much more severe illness, and strong vaccine resistance. Such a variant isn’t seen in early 2026, but scientists warn that risks grow with uncontrolled spread, especially in regions with low vaccination. Thus, expert recommendations for coming years focus on developing global early warning systems: viral sequencing, quick international data sharing, dynamic vaccine updates (especially mRNA) and flexible crisis planning. For Poland, this means improving epidemiological monitoring, better coordination between primary care, hospitals, and public health departments, and continuously educating the public that, though a full new pandemic is less likely than several years ago, severe periodic COVID-19 and flu waves will remain with us, requiring responsible adjustment—without returning to the harshest lockdowns.
What to Do If You Experience New Symptoms?
In the 2026/2027 season, as new COVID-19 variants and the “K variant” flu increasingly mimic a common cold, it’s crucial to follow a clear procedure when experiencing disturbing, unusual, or simply new symptoms. On the very first day you notice fever, sore throat, cough, sudden weakness, muscle pain, diarrhea, nausea, severe headache, or dizziness, limit contact with others—even if symptoms are mild. Stay home if possible, skip in-person work, social events, and crowded places—this simple step reduces the risk of spreading virus during the period when you are most contagious, often before the full illness develops. A good practice is to keep a brief “symptom diary”: note the date of symptom onset, severity, body temperature, medications taken, and any recent contact with others with COVID-19 or flu. This information helps doctors assess the situation and accelerate decisions about diagnostic tests or treatment changes. For new gastrointestinal symptoms (diarrhea, vomiting, abdominal pain) or neurological signs (severe headaches, balance problems, concentration issues, sudden confusion in elderly), do not dismiss them as “just indigestion” or tiredness—in the context of current variants, these may be early signs, especially if co-occurring with cough, runny nose, chills, or fever. Follow basic hygiene: frequent hand-washing, ventilate your home, don’t share utensils/towels with housemates, and cover mouth/nose when sneezing or coughing. If you must go out (pharmacy, testing), consider a mask on public transport and in closed rooms—you’ll reduce risk of infecting others and protect yourself from other viruses, which is a real “twindemic” threat this season.
The second pillar when experiencing new symptoms is rapid but mindful diagnostics and proper healthcare utilization. If symptoms are moderate and you’re not in a high-risk group, typically a contact with your primary care physician (by phone, e-visit, or in-person) within 24–48 hours is sufficient. Accurately describe your course: was onset sudden and “flu-like” with high fever and severe muscle aches (suggestive of flu or K variant), or more gradual with scratchy throat, mild cough, and moderate temperature (more common in milder COVID-19 variants)? Also mention previous COVID-19 or flu, vaccination status, and date of last vaccine, as these impact recommendations. For respiratory symptoms, at-home antigen testing for COVID-19 and—for at-risk persons (seniors, obese, heart/lung/diabetes/immunity disorders)—also flu testing is a sensible step. If positive, follow local public health guidelines: home isolation for the recommended period, notify close contacts (housemates, open-plan coworkers), and for severe symptoms—contact a doctor promptly regarding antivirals. Be especially alert for so-called alarm symptoms requiring immediate medical attention or an ambulance: increasing shortness of breath, feeling of air hunger, blue lips/fingers, chest pain/pressure, sudden speech/vision disturbances, seizures, loss of consciousness, very high fever not responding to drugs, and severe dehydration (rare urination, dry mouth, dizziness when standing). For the elderly and chronically ill, sudden overall deterioration, confusion, loss of appetite, or marked weakness are also warning signs—timely reaction is vital. Remember that some symptoms may linger for weeks after acute illness; in these cases, follow-up, extra testing (e.g., blood tests, oxygen saturation, chest X-ray, or ECG for chest pain), and gradual, safe return to activity without overstraining the body are recommended. This approach—combining self-monitoring, reasonable isolation, prompt testing, early doctor contact, and awareness of alarm symptoms—helps us adapt to ever-changing virus variants in 2026 and lowers the risk of severe disease for ourselves and those around us.
Summary
New COVID-19 and influenza waves, including variants like the “K variant,” are bringing many new and unusual symptoms—from hearing loss to intense migraines and rashes. It is increasingly difficult to distinguish COVID-19 from influenza, so it is vital to pay close attention to the diversity of symptoms and follow expert recommendations. Experts warn that another pandemic is not out of the question, and a swift response to emerging infections and symptoms is crucial to public health. Rapid diagnostics, proper treatment, and preventative measures are vital when unexplained symptoms develop.
