Fungal infections might be dangerous for Covid-19 patients with severe symptoms in ICU, experts say

Covid-19 patients with severe symptoms who end up in intensive care units (ICU) in hospital are at risk of contracting an invasive fungal infection that might influence their outcomes and affect treatment.

This is according to a recently published study which suggests these fungal co-infections in Covid-19 patients on ventilators may contribute to their high mortality rate.

Prof Carlien Pohl-Albertyn and Dr Obinna Ezeokoli, from the Pathogenic Yeast Research Group in the department of microbiology and biochemistry at the University of the Free State (UFS), recently published an article on the incidence of fungal infection in Covid-19 patients.

They are also in the process of publishing another article on the potential risk factors of fungal infections during treatment for Covid-19.

Pohl-Albertyn, who is the National Research Foundation (NRF) SA Research Chairs Initiative (SARChI) research chair in pathogenic yeasts, said there are several reasons why Covid-19 patients with severe symptoms in intensive care units are at risk of fungal infections.

“Severe Covid-19 causes changes in the immune system, such as increased release of cytokines (molecules involved in inflammation) and a decrease in certain white blood cells which help to fight other infections. These changes might make patients more susceptible to invasive fungal infections.

“Severe SARS CoV-2 infection also damages the lung tissue, making it easier for inhaled fungi, such as Aspergillus species, Cryptococcus neoformans, and mucoralean fungi, to cause invasive infections,” she said.

Pohl-Albertyn said many patients with severe Covid-19 have comorbidities, including diabetes, which made them more susceptible to fungal infections.

She said patients with severe Covid-19 in ICUs were often ventilated and have central venous catheters and urinary catheters inserted, which are also risk factors for fungal infections.

“Some drugs, such as corticosteroids used to treat the symptoms of severe Covid-19, may increase the risk of fungal infection, though the link between these drugs and fungal infection in Covid-19 has not been well studied yet.

“Some patients may be given broad-spectrum antibiotics to treat or prevent bacterial co-infection. These antibiotics could also kill the ‘good bacteria’ that help to keep the fungi in and on your body in check. If they are removed, the fungi that colonise the patients may overgrow and cause infection.”

According to her, any systemic fungal infection can be deadly, so in patients with Covid-19 it is definitely cause for concern.

In their recent article published in the South African Medical Journal, Pohl-Albertyn and Ezeokoli write that the incidence of severe infection and mortality in Covid-19 is said to be due in part to a lack of natural immunity and to viral replication in the lower respiratory tract, as well as superinfections, secondary infections or co-infections (these terms are often used interchangeably), leading to severe lung injury and acute respiratory distress syndrome (ARDS).

The researchers also report that studies conducted before the current Covid-19 pandemic have shown fungal infections are highly prevalent in the SA population, partly owing to the high incidence of HIV and Aids.

“Given the high prevalence of HIV/Aids in SA and the high number of people undergoing immunosuppressive therapies for other illnesses, co-infections with opportunistic fungal species may be affecting the current Covid-19 disease statistics in SA,” said the researchers.

TimesLIVE