COVID-19 continues to evolve with new variants emerging regularly due to ongoing mutations in the SARS-CoV-2 virus1 . These variants differ in how easily they spread, the symptoms they cause, and their impact on public health2 . Understanding the symptoms and characteristics of current and earlier COVID variants is essential for effective prevention, timely medical care, and reducing the risk of severe illness3 .
Current COVID Variants
SARS-CoV-2 has undergone continuous mutation since its emergence, resulting in successive dominant variants over time1 . As of early 2024 and into 2025, the predominant variants include JN.1, KP.3.1.1, and XFG (also known as the Stratus variant) 456. The JN.1 variant rapidly increased in prevalence in early 2024, becoming dominant in the U.S. before KP.3.1.1 rose in prominence4 . The XFG variant, first detected in early 2025, has spread globally and is currently a major circulating strain5 6.
These variants share many characteristics with previous Omicron subvariants, including high transmissibility and generally milder disease severity compared to earlier strains like Delta7 1. The XFG (Stratus) variant is notable for its ability to evade some immune defenses, though it does not appear to cause more severe illness than prior variants5 6. Similarly, the NB.1.8.1 (Nimbus) variant is highly transmissible due to mutations that enhance its ability to bind to human cells but does not increase severity of disease8 9.
Ongoing genomic surveillance is critical to monitor the spread and impact of these variants, as new mutations may influence transmissibility, vaccine effectiveness, and clinical outcomes10 2.
Common COVID-19 Symptoms
Symptoms of COVID-19 vary by variant but generally include respiratory and systemic signs11 . The most common symptoms reported across current variants such as XFG (Stratus) and NB.1.8.1 (Nimbus) include:
- Sore throat, often severe or sharp, especially with Nimbus8 9
- Nasal congestion or runny nose12 11
- Cough11 5
- Fever or chills11 5
- Fatigue or persistent tiredness8 11
- Headache11 5
- Muscle or body aches11 5
- Sneezing8
- Digestive symptoms such as nausea, vomiting, or diarrhea (less common) 811
Loss of taste or smell, a hallmark symptom in earlier COVID variants, is now less common with Omicron and its subvariants, including the current strains13 14. Symptoms typically appear 2 to 14 days after exposure, with Omicron subvariants showing shorter incubation periods15 7.
The severity of symptoms remains similar to previous Omicron infections, with most cases being mild to moderate14 . Recovery times generally range from five to ten days, depending on individual factors16 .
💡 Did You Know?
The CDC continues to update the list of COVID-19 symptoms as new variants emerge, reflecting ongoing research and surveillance17 .
Earlier COVID Variants
Earlier variants of SARS-CoV-2, including several Omicron subvariants and others, have shaped the evolving symptom profile and clinical outcomes of COVID-19. These variants generally had longer incubation periods and more severe disease compared to recent strains15 7.
COVID Variant HV.1
HV.1 was among the earlier Omicron subvariants characterized by high transmissibility but relatively mild symptoms. It exhibited a shorter incubation period than pre-Omicron variants, typically 2 to 5 days15 . Common symptoms included cough, fever, fatigue, and nasal congestion11 .
COVID Variant BA. 2.86
BA.2.86 is an Omicron descendant with symptom profiles resembling other circulating Omicron subvariants11 . It caused symptoms such as sore throat, cough, congestion, and fatigue, with less frequent loss of taste or smell13 11.
COVID Variant JG. 3
JG.3 was noted for its rapid spread but did not significantly change the symptom profile compared to other Omicron variants. Symptoms were consistent with mild respiratory illness, including nasal congestion and cough12 11.
COVID Variant BA. 2
BA.2 was an early Omicron subvariant with high transmissibility and milder disease severity compared to Delta7 . It showed a shorter incubation period and symptoms such as sore throat, cough, and fatigue15 7.
COVID Variant JD. 1. 1
JD.1.1 maintained the typical Omicron symptom pattern, with nasal congestion frequently reported and loss of smell or taste less common than in earlier variants13 12.
COVID Variant HK. 3
HK.3 was similar to other Omicron subvariants in symptom presentation, causing mild to moderate respiratory symptoms and systemic signs like fatigue and headache11 .
“Symptoms of current circulating variants are largely consistent with prior Omicron subvariants, with nasal congestion frequently reported and loss of smell or taste less common than earlier variants.”
— Dirk Eggink, RIVM14
COVID-19 Prevention Strategies
Preventing COVID-19 infection remains a priority, especially as new variants emerge. SARS-CoV-2 primarily spreads through airborne particles inhaled from infected individuals and via droplets from coughs and sneezes3 . Preventive measures that reduce transmission include:
- Vaccination, which remains effective against severe illness from current variants3 5
- Wearing masks in high-risk or crowded indoor settings3
- Practicing good hand hygiene by frequent washing or sanitizing3
- Maintaining physical distancing from infected or symptomatic individuals3
- Improving indoor ventilation to reduce airborne virus concentration3
- Staying home and isolating when symptomatic or after a positive test3 18
Caretakers and those with unavoidable exposure can reduce risk by using masks, hand hygiene, and minimizing close contact3 . Vaccination, including updated booster doses, is especially recommended for older adults, immunocompromised persons, and those with chronic health conditions8 5.
| Prevention Strategy | Key Benefit | Reference |
|---|---|---|
| Vaccination | Reduces severe illness and death | 35 |
| Mask-wearing | Lowers viral transmission | 3 |
| Hand hygiene | Prevents surface and droplet spread | 3 |
| Physical distancing | Limits close contact transmission | 3 |
| Ventilation improvement | Decreases airborne viral load | 3 |
When to Seek Medical Care
Most COVID-19 cases are mild and can be managed at home. However, certain symptoms and risk factors warrant prompt medical attention. Emergency warning signs include:
“COVID-19 is getting around, causing sore throats, congestion and coughing. The current dominant strain of COVID-19 is the Stratus variant also called XFG. The symptoms of the XFG COVID-19 strain are similar to previous strains.”
— Ashley Lipps, MD, Ohio State Wexner Medical Center16
- Trouble breathing or shortness of breath3 18
- Persistent chest pain or pressure3 18
- New confusion or inability to stay awake3 18
- Pale, gray, or blue-colored lips, face, or nail beds, indicating low oxygen3 18
People at higher risk of severe disease, such as older adults and those with underlying health conditions, should seek medical advice promptly upon diagnosis or worsening symptoms3 . Moderate symptoms that interfere with daily activities also warrant consultation for guidance and possible antiviral treatment3 8.
Early medical intervention improves outcomes and can reduce the risk of complications3 . Testing is recommended for those eligible for antiviral therapies, ideally within five days of symptom onset8 3.
“Early medical intervention improves outcomes in severe COVID-19, especially for older adults and those with comorbidities.”3
COVID Variant Symptoms Summary
The symptom profile of COVID-19 has evolved with the virus. Current variants like XFG (Stratus) and NB.1.8.1 (Nimbus) cause symptoms similar to previous Omicron subvariants, including sore throat, congestion, cough, fatigue, and headache11 5. Loss of taste or smell is now less common13 14.
Symptoms typically appear within 2 to 14 days after exposure, with Omicron subvariants showing shorter incubation periods15 7. Most cases are mild to moderate, with recovery in about five to ten days16 . Severe symptoms such as difficulty breathing, chest pain, or altered consciousness require immediate medical care3 18.
| Symptom | Frequency in Current Variants | Notes | Reference |
|---|---|---|---|
| Sore throat | Common | Sometimes sharp/stabbing (Nimbus) | 895 |
| Nasal congestion | Frequent | More common than in earlier variants | 1211 |
| Cough | Common | Mild to moderate | 115 |
| Fatigue | Common | Persistent in some cases | 811 |
| Loss of taste or smell | Less common | Compared to pre-Omicron variants | 1314 |
| Fever or chills | Common | Varies by individual | 115 |
| Headache | Common | 115 |
