Why people suffer despite being negative for Covid? It must be long cold

London: People may experience long-term symptoms -- or "long colds" -- after acute respiratory infections such as colds, influenza, or pneumonia, and it may be as common as long Covid, finds a study, explaining why some people continue suffer prolonged symptoms despite testing negative for SARS-CoV-2 virus.

The findings, published in eClinicalMedicine, suggest that there may be long-lasting health impacts following non-Covid acute respiratory infections that are currently going unrecognised.

However, the researchers do not yet have evidence suggesting that the symptoms have the same severity or duration as long Covid.

The study analysed data from 10,171 UK adults, with responses collected via questionnaires and statistical analysis carried out to identify symptom clusters.

The findings showed that some of the most common symptoms of the "long cold" included coughing, stomach pain, and diarrhoea more than four weeks after the initial infection.

In comparison, those recovering from Covid-19 or having long Covid were more likely to experience light-headedness or dizziness and problems with taste and smell.

"Our findings shine a light not only on the impact of long Covid on people's lives, but also other respiratory infections. A lack of awareness -- or even the lack of a common term -- prevents both reporting and diagnosis of these conditions," said lead author Giulia Vivaldi, researcher from Queen Mary University of London (QMUL) in the UK.

Vivaldi noted that along with research into long Covid, the lasting effects of other acute respiratory infections must also be investigated. "These 'long' infections are so difficult to diagnose and treat primarily because of a lack of diagnostic tests and there being so many possible symptoms. There have been more than 200 investigated for long Covid alone," Vivaldi said.

"Ongoing research into the long-term effects of Covid-19 and other acute respiratory infections is important because it can help us to get to the root of why some people experience more prolonged symptoms than others," said Professor Adrian Martineau, Chief Investigator of the study and Clinical Professor of Respiratory Infection and Immunity at QMUL.

"Ultimately this could help us to identify the most appropriate form of treatment and care for affected people," Martineau added.