Five years since the World Health Organisation declared the Covid-19 pandemic, scientists are unravelling how the virus can impact our bodies long after an infection.
Among the most recognised long-term issues is long Covid, marked by symptoms persisting for at least three months post-infection, such as chronic fatigue and brain fog. It is estimated that more than 400 million people worldwide have experienced some form of long Covid.
However, not all long-term complications are classified as long Covid. Damage to the lungs, heart and gut can also emerge after recovery, posing significant health challenges.
Covid’s ability to incite widespread inflammation appears to play a central role in these lingering effects. In most people, inflammation decreases as the infection subsides. However, if it becomes too intense or lingers, it can disrupt various bodily functions.
The lungs: Covid can irritate the lungs, leading to persistent symptoms like shortness of breath and coughing. Severe cases may result in pneumonia, scarring and tissue nodules that can permanently impact lung capacity.
The gut: Many people with Covid report gastrointestinal issues like diarrhoea, nausea and abdominal pain, with some experiencing these problems for months or even years. Research suggests Covid can disrupt the gut microbiome, harming beneficial microbes while encouraging harmful ones. This imbalance can increase inflammation, potentially leading to chronic gut problems.
The brain: Neurological symptoms like headaches, dizziness and brain fog are common during Covid infection, and roughly 20–30% of those infected report lingering cognitive issues months later. Researchers suspect that prolonged inflammation and possible disruption to the blood‑brain barrier contribute to these symptoms.
The heart: Covid has been linked to an increased risk of heart attacks, strokes and arrhythmias for up to three years post-infection. Inflammation caused by the virus can damage heart muscle and blood vessels, increasing the risk of blood clots.
The circulatory system: Some people with long Covid struggle with blood circulation, resulting in fatigue, shortness of breath and difficulty exercising. Inflammation may impair nerves that regulate blood flow and muscle function is weakened.
While the pandemic’s acute phase is behind us, the long-term impacts of Covid-19 are still being understood. Recognising and addressing these persistent issues is crucial. If you are concerned about any symptoms you’re experiencing, please speak with your GP.