In the midst of the pandemic, India has reported that it suffers from an unusually high number of mucormycosis cases, and that more than 80% of patients need surgery immediately because the death rate can reach 94%.
But what does this disease have to do with covid-19 ? It is an opportunistic fungal infection caused by various species of fungi belonging to the Mucorales order and which, in the case of India, may be associated with the high rates of infection by the new coronavirus that the country suffers .
Why? Because mucorals are considered opportunistic pathogens, which means they require a suppressed immune system or other underlying condition. So frequent are they that we could be talking about the third most common cause of invasive fungal infection in immunosuppressed patients.
The evils of poverty
To date, mucormycoses have been associated with high morbidity and mortality. In fact, mucorals can cause lethal infections in a larger and more heterogeneous population than other opportunistic fungi.
Currently 27 different species of mucorales are known, distributed in 11 genera that have been identified as causative agents . The most frequent is the Rhizopus arrhizus species , which appears in 70% of all cases.
Mucormycosis is not transmitted from person to person, and it can be acquired in different ways. The nose, sinuses, eyes, and brain become infected more often, causing a serious infection called rhinocerebral mucormycosis, which is often fatal. When inhaled the spores can invade the lungs and cause the lung variant.
The digestive tract becomes infected by ingesting the spores, leading to gastric mucormycosis. A fourth form of infection occurs when spores enter through a break in the skin, leading to skin disease. The fifth form is called disseminated, and the sixth variant is a miscellany of other types that can cause endocarditis (inflammation of the inner lining of the heart chambers and valves) or osteomyelitis (bone infection).
An old acquaintance
The disease was first described in 1876 in Germany by Paul Fürbringer after examining a patient who died of cancer. In his right lung he showed a large number of fungal hyphae and some sporangia.
Shortly after, in 1885, Arnold Paltauf published the first case of disseminated mucormycosis , which he called “mycosis mucorina.” Over time, more were diagnosed, and the incidence of the disease has not stopped growing since then.
In Spain, in 2005 there were 0.43 cases per million inhabitants and 0.62 cases per 100,000 hospital admissions. In neighboring France, the incidence doubled from 1997 to 2006 and in Belgium the incidence increased 10-fold in just one decade . It is currently estimated that the incidence of this type of infection in countries with validated registries is approximately 1 to 1.5 cases per million inhabitants / year.
The probability of suffering from mucormycosis increases in diabetic patients with compromised immune systems
In general, the infection causes pain, fever, sometimes cough, and causes severe tissue damage with rapid tissue destruction, leading to severe necrosis.
The probability of suffering from mucormycosis increases in diabetic patients with compromised immune systems. Mucoral fungi infect immunosuppressed individuals with predisposing risk factors, including uncontrolled diabetes, chemotherapy, hematological diseases, organ transplantation, elevated blood iron levels, or corticosteroid therapy, among others.
The prevalence is 70 times higher in India
According to some analyzes, India is the country most affected by mucormycosis and contributes with more than 40% of all reported cases in the world. The estimated prevalence of the disease is around 70 times higher there than in the global data. Risk factors that predispose to suffering from it in this country may include socioeconomic conditions, poor hygienic conditions, and the high prevalence of diabetes mellitus in the population .
According to the available data, in India patients with post- pulmonary tuberculosis and chronic kidney disease are at additional risk of developing this infection. Most people with a positive or suspected infection are treated with high doses of amphotericin B, which is administered intravenously. Isavuconazole, orally or intravenously, is an alternative, and posaconazole may also be effective, especially as consolidation therapy.
Although Rhizopus arrhizus is the most common etiologic agent of mucormycosis in India, infections by other fungi are increasing. The broad spectrum of agents involved in this infection emphasizes the need to improve clinical routines and determine the exact prevalence of the disease in various populations at risk.
It should not be forgotten that early diagnosis and treatment are essential to prevent death or to avoid extensive surgery, which often causes facial disfigurement.