Long COVID: What We Now Know & Why COVID Still Matters

Even though the peak of the pandemic has passed, COVID-19 continues to leave a long imprint on many Australians. Since restrictions were lifted in late 2022, daily life has largely returned to normal — but at the same time, prevention has relaxed. Fewer people wear masks when they’re unwell, and it’s now common to see individuals still out and about with “mild” symptoms, assuming it’s nothing to worry about.

But COVID isn’t the same for everyone. Two people can have the same infection and walk away with completely different experiences. Some feel fine after a few days, while others develop lingering symptoms that last for months — or even years. So the idea of “COVID didn’t hit me hard the first time, so I’m not at risk” simply doesn’t reflect what research is showing today.

What is long COVID?

Most people recover from COVID-19 within a few weeks. However, some continue to experience symptoms for much longer — sometimes for months. This lingering impact is known as long COVID, also called post-acute sequelae of SARS-CoV-2 or in simpler terms, post COVID-19 condition.

The Australian National Clinical Evidence Taskforce describes long COVID as symptoms that develop during or after a COVID-19 infection, last for more than 12 weeks, and cannot be explained by another diagnosis. These symptoms often appear in clusters, may overlap, and can fluctuate or change over time. Because long COVID can affect any system in the body, the range of possible symptoms is broad — from fatigue and breathing issues to cognitive and neurological changes.

Symptoms that persist before the 12-week mark may still be considered part of a post-COVID condition while health professionals assess whether another cause may be involved.

It’s also important to note that defining long COVID is not as straightforward as one believed it to be. Australian and international organisations continue to refine their understanding, and research shows wide variation in how long COVID is measured. Different studies use different methods (such as self-reported symptoms vs. clinical records), and factors like variants, reinfection, and vaccination history add complexity. Because of this, estimates of how common long COVID is can vary quite a bit.

How common is long COVID?

Because COVID-19 peaked later in Australia than in many other countries, research into long COVID here has taken a little longer to build momentum. But from the data we do have, it’s clear that long COVID is affecting a noticeable portion of people who catch the virus — even those who had mild symptoms at the time.

Prevalence of long COVID in Australia

Because Australia saw its largest COVID wave in 2022, local research into long COVID has taken time to build. But the studies we do have point to a consistent picture:

1. AIHW estimates

The Australian Institute of Health and Welfare suggests that around 5% to 10% of people who get COVID-19 continue to experience symptoms lasting longer than 12 weeks. These figures align with the definition used by the Australian National Clinical Evidence Taskforce.

2. Findings from the Agency for Clinical Innovation (ACI)

The ACI’s reviews highlight that estimates vary widely across international research (from 9% to 81%) because of differences in:

• study design
• how symptoms are defined
• who is included
• how long people are followed up
• the impact of variants, reinfections, and vaccination

Despite these variations, Australian studies fall toward the lower end of the range — but still confirm that long COVID is a real and ongoing issue.

Examples from Australian studies

• A Melbourne long COVID clinic found that 5.7% of COVID-positive patients surveyed at eight weeks post-infection still experienced symptoms needing medical management — most commonly memory or concentration issues, breathlessness, and extreme fatigue.
  
• Victorian studies estimate long COVID rates ranging from 0.17% to 4.4% among adults with symptomatic infections. Rates were lower among vaccinated individuals infected with Omicron (0.09% in non-hospitalised cases and 1.9% in hospitalised cases).

Long COVID in international research

International research shows a wider range of prevalence rates, reflecting differences in definitions and data quality.

1. WHO estimate

The World Health Organization estimates that around 6 in every 100 people with COVID-19 go on to develop long COVID.

2. OECD survey findings

Across 19 countries, the OECD’s PaRIS survey found:

• 7% of primary care patients aged 45+ reported ever having long COVID
  
• 5% reported ongoing symptoms at the time of the survey

This suggests a considerable proportion of older adults continue to be affected.

What large global reviews are showing

A major systematic review published in 2025, analysing 429 studies, found that:

• The global pooled prevalence of long COVID is 36%
  
• Prevalence remained high across different timelines:
  
  • 35% within the first year
    
  • 46% among people followed for one to two years
    
• The most common symptom groups reported were:
  
  • Respiratory symptoms – 20%
    
  • General fatigue – 20%
    
  • Psychological symptoms – 18%
    
  • Neurological symptoms – 16%

The review also identified several risk factors linked to higher long COVID prevalence:

• Being unvaccinated
  
• Infection during pre-Omicron waves
• Female sex, with women more likely to report lasting symptoms

Why estimates vary so much

The ACI and other health bodies note several reasons why prevalence numbers differ:

• No single global definition of long COVID
  
• Different symptoms included in each study
  
• Variation in follow-up duration
  
• Use of self-reported symptoms vs. clinically verified cases
  
• Influence of COVID variants and vaccination status

You can also explore our related articles on the COVID-19 variants seen in Australia, which help explain how each wave has shaped current long-term health outcomes:

• The Top 3 COVID-19 Variants in Australia Right Now: What You Need to Know’
• NB.1.8.1 in Australia: Understanding the Latest COVID-19 Variant
• New COVID Variant XFG: What Makes Stratus Different, and What to Expect

What are the main long-term effects of long COVID: Symptoms & health issues

Long COVID can affect almost every system in the body, and symptoms often appear in clusters, fluctuate over time, or emerge weeks after someone appears to have recovered. More than 200 symptoms have been documented in the literature, but most fall into a few key groups.

Below is a clear breakdown of the most commonly reported long-term effects, drawn from the Australian Clinical Innovation (ACI) evidence tables and international studies.

1. Respiratory symptoms

Respiratory issues are among the most widely reported long-term effects.

Common symptoms include:

• Shortness of breath or difficulty breathing
  
• Persistent cough
  
• Chest pain or chest tightness
  
• Reduced exercise tolerance

A cohort study in Belgium followed survivors of severe and critical COVID-19 three months after hospitalisation. It found that:

• 25% continued experiencing shortness of breath
  
• 45% had a decrease in lung diffusion capacity (DLCO)
  
• 17% showed lung abnormalities on imaging
  
• 21% displayed signs of fibrosis affecting more than 5% of lung tissue

2. Generalised symptoms

These symptoms are common across almost all long COVID studies:

• Fatigue (one of the most consistent symptoms)
  
• Weakness or effort intolerance
  
• Post-exertional malaise (symptoms worsening after activity)
  
• Generalised pain
  
• Rash or hair loss

A cross-sectional study in Western India followed adults aged 19–70 with persistent symptoms and showed that ongoing fatigue remained one of the most persistent issues, even up to four years post-infection.

3. Cardiovascular symptoms

COVID-19 can influence the heart and circulatory system long after infection.

Common symptoms and conditions include:

• Chest tightness or chest pain
  
• Cardiac symptoms such as arrhythmias or palpitations
  
• Shortness of breath during physical activity
  
• Reduced cardiovascular fitness
  
• Autonomic dysfunction, including
  
  • POTS (postural orthostatic tachycardia syndrome)

Longer-term risks have also been observed, with some studies showing increased incidences of:

• Cardiovascular disease
  
• Interstitial lung disease
  
• Diabetes
  
• Dyslipidaemia

4. Neurological & cognitive symptoms

Neurological symptoms are widely reported in long COVID and can affect thinking, memory, sleep, and sensory processing. An updated narrative review published in Dementia & Neuropsychologia (2024) examined neurological manifestations of long COVID by analysing findings across multiple studies. The review highlighted that:

• Neurological symptoms can appear after mild or severe infections
  
• They are more commonly reported in young adults and women
  
• Cognitive issues and fatigue were among the most frequent symptoms in a meta-analysis of 81 studies involving patients 12 weeks or more after infection
  
• Symptoms often involve cognition, sleep, smell disorders, psychiatric changes, headaches, and more

This review emphasised that neurological long COVID contributes significantly to ongoing morbidity and may require tailored long-term support.

In general, common neurological and cognitive symptoms include:

• Brain fog
  
• Memory difficulties
  
• Trouble focusing or multitasking
  
• Sleep disturbances
  
• Headaches
  
• Loss or change in smell or taste

5. Psychological & mental health symptoms

Psychological effects are consistently observed across many long COVID studies.

Common issues include:

• Anxiety
  
• Depression
  
• Sleep problems
  
• Stress sensitivity
  
• Low mood or irritability

6. Gastrointestinal symptoms

Some people experience digestive issues months after infection:

• Abdominal pain
  
• Nausea or vomiting
  
• Diarrhoea or constipation
  
• Heartburn
  
• Irritable bowel syndrome–like symptoms
  
• Inflammatory bowel-type symptoms (in rarer cases)

7. Musculoskeletal symptoms

These often occur alongside generalised symptoms.

Common issues include:

• Muscle pain
  
• Muscle weakness
  
• Joint pain

These symptoms can overlap with fatigue and neurological issues.

8. Other reported long-term effects

Though less common, studies have noted:

• Kidney-related outcomes (though more studies need to be done)
  
• Metabolic disruptions (diabetes, cholesterol changes)
  
• Persistent inflammation
  
• Skin changes

These conditions can appear in combination or develop months after infection.

How common are the long COVID symptoms? (Prevalence by symptom type)

Research shows that long COVID doesn’t affect every system equally. Some symptoms appear far more frequently than others, and their prevalence can vary depending on the variant, age group, and whether someone was hospitalised.

Here’s a simple breakdown based on ACI’s larger reviews and Australian-linked studies:

Most common long COVID symptom groups

• Fatigue-related symptoms – among the most frequently reported across all studies
  
• Cognitive and neurological symptoms (e.g., memory issues, poor concentration)
  
• Respiratory symptoms such as ongoing breathlessness
  
• Psychological symptoms including low mood or anxiety
  
• Loss of smell or taste in some individuals
  
• Hair loss (alopecia) and other systemic symptoms appearing in certain studies

A 2025 systematic review comparing infected individuals to uninfected controls found that the relative risk of developing symptoms such as loss of smell, loss of taste, impaired memory, poor concentration, and hair loss ranged between 2.68 and 4.31 times higher at 28 days after infection.

Another large global analysis covering 22 countries found:

• 6.17% of symptomatic COVID-19 patients experienced at least one long COVID symptom cluster (fatigue, cognitive, or respiratory) at three months after infection
  
• By 12 months, this decreased to 0.9%, showing gradual recovery for many — though not all — individuals

For children, symptom prevalence tends to be lower, but still present. For example, one Australian estimate found that 1.7% of non-hospitalised children and up to 5.2% of hospitalised children reported symptoms at three months post-infection.

What this means for individuals — Practical takeaways

Long COVID shows us that the effects of COVID-19 don’t always end with a negative test. People can recover quickly, recover slowly, or develop symptoms weeks after infection — and there’s no way to predict who will be affected. Some individuals have only mild discomfort, while others experience symptoms that last months or even years. This is why being mindful of our own health, and the people around us, continues to matter.

Here are some simple and practical takeaways:

1. Listen to your body and monitor ongoing symptoms

If you’re still feeling unwell after COVID-19 — whether it’s fatigue, breathlessness, brain fog, poor sleep, or anything that feels “off” — don’t ignore it. Symptoms can come and go, or they may appear weeks after infection, which is common in long COVID.

2. Seek medical advice if symptoms persist

A GP can help rule out other causes, document symptoms, and guide you to appropriate support. Long COVID symptoms overlap with many conditions, especially those of respiratory illnesses, so early review can be helpful.

Read related article: RSV vs. COVID-19 vs. Influenza: All You Need to Know

3. Pace yourself to avoid flare-ups

Many people experience worsening symptoms after physical or mental exertion (known as post-exertional malaise). Gentle pacing, rest, and breaking tasks into smaller steps can help.

4. Support your general health

Good sleep, hydration, balanced meals, sunlight, and stress management can make day-to-day symptoms easier to manage.

Staying considerate: Protecting yourself and others

One of the biggest lessons from long COVID research is that everyone responds differently to infection. You may feel fine after a few days, but someone else in your household, workplace, or community could become very unwell — and some may go on to experience long-term complications.

Because of this, small everyday precautions still matter:

1. Stay home if you feel unwell

Even if symptoms seem mild, resting at home helps prevent others from becoming sick — especially those who may be more vulnerable.

2. Wear a mask when sick or recovering

A mask protects people around you while you’re contagious or when you’re out and about. It’s a simple step that significantly reduces the spread of respiratory viruses.

3. Practise good hand hygiene

Regular handwashing or using sanitiser helps prevent passing viruses onto surfaces and shared spaces.

4. Give others space if you’re unwell

Keeping a bit of distance — especially in crowded or indoor places — helps protect those who may not cope well with infection.

A note on care and consideration for others

We all live our lives by our own choices and routines — but when it comes to illness, especially something like COVID-19, our decisions don’t affect only us. They can impact the people we live with, work with, and cross paths with every day.

A simple action like choosing to stay home when unwell, wearing a mask, or keeping your distance isn’t just about protecting yourself. It’s an act of respect and mindfulness for those around you — including people who may be more vulnerable.

Taking illness seriously doesn’t mean living in fear. It simply means recognising that we share our spaces, our air, and our communities. A little care goes a long way in keeping everyone safer and healthier.

Check, Manage & Monitor: Shop Your COVID Essentials Collection at Aussie Pharma Direct