Influenza is thought to infect a billion people worldwide each year (WHO figures 2018), which is about 1 in 7 of the total population of the earth! A few million of those cases develop severe symptoms that require them to be treated in hospital. Up to 650 000 cases result in the death of the patient.
Why do so many die? What can we do to reduce that number of deaths?
We know that severe influenza causes significant damage to lung tissue. Such damage may make those patients vulnerable to aspergillosis, so researchers started to look for any such cases as acute invasive aspergillosis is treatable so if that infection is causing some of those deaths, the right treatment could help save lives. The researchers quickly found signs of aspergillosis but what grabbed their attention, even more, where the number of patients that were found. In one of the first studies 44% of influenza patients who had died were identified as having aspergillosis, far more than might be suspected. This was subsequently found to be a high figure and when they started to look for IA other countries found much lower numbers, but still very significant numbers of people who might be helped if treated for aspergillosis.
Since 2019 we have all been experiencing a pandemic from a different type of virus: SARS-CoV-2 that has so far killed over 2 million people globally. This virus also damages the lung tissue of patients experiencing severe symptoms so researchers started to test these new patients for signs of aspergillosis and again high numbers were initially found in some countries, not so high in others. Nevertheless again there is potential to save significant numbers of lives by treating affected patients for aspergillosis.
Exactly how many lives might be helped is difficult to estimate but it is likely that looking for ‘hidden aspergillosis’ in COVID patients will be one way to reduce mortality. Read the consensus document in The Lancet here.
It feels a little like whenever we look for aspergillosis in severely ill respiratory patient groups eg influenza, bronchiectasis, cystic fibrosis, chronic obstructive pulmonary disease, tuberculosis and even occasionally lung cancer, we find aspergillosis sometimes in far higher numbers than we might expect.