Mucormycosis, past and present: a comprehensive review

Future Microbiol. 2023 Feb:18:217-234. doi: 10.2217/fmb-2022-0141. Epub 2023 Mar 27.

Abstract

Mucormycosis is an emerging opportunistic angioinvasive fungal infection. Predisposing factors such as diabetes, neutropenia, long-term corticosteroid therapy, solid organ transplantation and immunosuppression contribute to its occurrence. This disease was not of significant concern prior to the COVID-19 pandemic, but gained prominence due to infections in COVID-19 patients. Mucormycosis needs special attention and coordinated efforts of the scientific community and medical professionals to reduce morbidity and mortality. Here we present an overview of the epidemiology and prevalence of mucormycosis in the pre- and post-COVID-19 eras, the factors that contributed to the abrupt increase in COVID-19-associated mucormycosis (CAM), the actions taken by the regulatory agencies (including Code Mucor and CAM registry), the existing diagnostic tools and CAM management strategies.

Keywords: CAM; COVID-19-associated mucormycosis; angioinvasion; black fungus; diagnosis; epidemiology; invasive fungal disease; mucormycosis; pathogenesis; post-COVID-19 complications; treatment.

Plain language summary

The devastating effects of the COVID-19 pandemic have been further enhanced by various secondary illnesses, particularly opportunistic fungal infections such as mucormycosis. Mucormycosis or ‘black fungus’ primarily affects people with weakened immunity, those with medical conditions such as diabetes or cancer and those who use medications that reduce the body's capacity to resist infections and disease. The infection starts in the sinuses or the lungs after breathing in spores of the black fungus from the air. In just 2 months between 5 May and 12 July 2021, this uncommon but fatal fungal illness was responsible for 41,512 cases and 3554 fatalities in India alone. The government of India declared a mucormycosis epidemic in May 2021. The majority of such cases occurred during active SARS-CoV-2 outbreaks in India in 2021. Black fungus took over while the host defenses were compromised and the globe was preoccupied tackling the COVID-19 pandemic. Steroids prescribed in amounts and time spans that far exceeded WHO recommendations to manage severe COVID-19 cases, potentially weakened patients' immune systems, and raised blood sugar levels making them vulnerable to fungal invasion. Early diagnosis and treatment are the keys to a patient's survival. Simple means such as maintaining hygienic conditions, avoiding contact with an infected person, judiciously using steroid medications and antibiotics and properly managing high blood sugar can help protect an individual from black-fungus infection.

Publication types

  • Review

MeSH terms

  • COVID-19*
  • Humans
  • Immunosuppression Therapy
  • Mucormycosis* / diagnosis
  • Mucormycosis* / drug therapy
  • Mucormycosis* / epidemiology
  • Neutropenia*
  • Opportunistic Infections*
  • Pandemics