Mucormycosis: the black fungus hitting Covid-19 patients

 

India is struggling against a rapid increase in Covid-19 cases, but a nasty and rare fungal infection affecting some coronavirus patients is dealing the country a double blow.

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Fungal infections can be devastating. And one in particular – mucormycosis – is adding to the burden of suffering in a country already in a deep Covid-19 crisis. We've seen reports from India of infections with mucormycosis, often termed "black fungus", in patients with Covid-19, or who are recovering from the coronavirus. 

As of March this year 41 cases of Covid-19-associated mucormycosis had been documented around the world, with 70% in India. Reports suggest the number of cases is now much higher, which is unsurprising given the current wave of Covid-19 infections in India.

But what is mucormycosis, and how is it linked with Covid-19?

What is mucormycosis?

Mucormycosis, formerly known as zygomycosis, is the disease caused by the many fungi that belong to the fungal family "Mucorales". Fungi in this family are usually found in the environment – in soil, for example – and are often associated with decaying organic material such as fruit and vegetables. 

The member of this family most often responsible for infections in humans is called Rhizopus oryzae. In India though, another family member called Apophysomyces, found in tropical and subtropical climates, is also common. 

The fungi that cause muC

In the laboratory, these fungi grow rapidly and have a black-brown fuzzy appearance.

Those that cause human disease grow well at body temperature and in acidic environments – the kind seen when tissue is dead, dying or associated with uncontrolled diabetes.

How do you get mucormycosis?

Fungi in the Mucorales family are considered opportunistic, meaning they usually infect people with an impaired immune system, or with damaged tissue. Use of drugs which suppress the immune system such as corticosteroids can lead to impaired immune function, as can a range of other immunocompromising conditions, like cancer or transplants. Damaged tissue can occur after trauma or surgery.

There are three ways humans can contract mucormycosis – by inhaling spores, by swallowing spores in food or medicines, or when spores contaminate wounds. 

Inhalation is the most common. We actually breathe in the spores of many fungi every day. But our immune systems and lungs, if healthy, generally prevent them from causing an infection. 

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When our lungs are damaged and our immune systems suppressed, such as is the case in patients being treated for severe Covid-19, these spores can grow in our airways or sinuses, and invade our bodies' tissues. 

Mucormycosis can manifest in the lungs, but the nose and sinuses are the most common site of mucormycosis infection. From there it can spread to the eyes, potentially causing blindness, or the brain, causing headaches or seizures. 

Crematoriums in New Delhi have be

It can also affect the skin. Life-threatening wound infections have been seen after injuries sustained during natural disasters or on battle fields where wounds have been contaminated by soil and water.

In the environment

There have been very few mucormycosis infections associated with Covid-19 in countries other than India. So why is the situation there so different? 

Before the pandemic, mucormycosis was already far more common in India than in any other country. It affects an estimated 14 in every 100,000 people in India compared to 0.06 per 100,000 in Australia, for example. 

Globally, outbreaks of mucormycosis have occurred due to contaminated products such as hospital linens, medications and packaged foods. But the widespread nature of the reports of mucormycosis in India suggests it's not coming from a single contaminated source.

A recent summary of Covid-19-associated mucormycosis showed 94% of patients had diabetes

Mucorales can be found in soil, rotting food, bird and animal excretions, water and air around construction sites, and moist environments.

Although never compared, it may be that Australia has a lower environmental burden of Mucorales than in India. 

But there could be another factor at play in India – diabetes.

When diabetes is poorly controlled, blood sugar is high and the tissues become relatively acidic – a good environment for Mucorales fungi to grow. This was identified as a risk for mucormycosis in India (where diabetes is increasingly prevalent and often uncontrolled) and worldwide well before the Covid-19 pandemic. Of all mucormycosis cases published in scientific journals globally between 2000-2017, diabetes was seen in 40% of cases. 

A recent summary of Covid-19-associated mucormycosis showed 94% of patients had diabetes, and it was poorly controlled in 67% of cases. 

A perfect storm

People with diabetes and obesity tend to develop more severe Covid-19 infections. This means they're more likely to receive corticosteroids, which are frequently used to treat Covid-19. But the corticosteroids – along with diabetes – increase the risk of mucormycosis.

Meanwhile, the virus that causes Covid-19 can damage airway tissue and blood vessels, which could also increase susceptibility to fungal infection. 

Mucormycosis can be life thre S

So damage to tissue and blood vessels from Covid-19 infection, treatment with corticosteroids, high background rates of diabetes in the population most severely affected by the coronavirus, and, importantly, more widespread exposure to the fungus in the environment are all likely to be playing a part in the situation we're seeing with mucormycosis in India.

Treatment challenges

In many Western countries, we've seen increased cases of another fungal infection, Aspergillosis, in patients who had severe Covid-19 infections, needed intensive care management and received corticosteroids. This fungus is also found in the environment but belongs to a different family. 

As Aspergillosis is the most common opportunistic fungus globally, and we have tests to rapidly diagnose this infection. But this is not the case with mucormycosis.

For the many patients affected with mucormyosis, the outcome is poor. About half of patients affected will die and many will sustain permanent damage to their health. 

Mucormycosis can spread to the eyes, potentially causing blindness, or the brain, causing headaches or seizures

Diagnosis and intervention as early as possible is important. This includes control of blood sugar, urgent removal of dead tissue, and antifungal drug treatment. 

But unfortunately, many infections will be diagnosed late and access to treatment is limited. This was the case in India prior to Covid-19 and the current demands on the health system will only make things worse. 

Controlling these fungal infections will require increased awareness, better tests to diagnose them early, along with a focus on controlling diabetes and using corticosteroids wisely. Patients will need access to timely surgery and antifungal treatment. But there also needs to be more research into prevention of these infections.

* Monica Slavin is an expert in lung infections at the Royal Melbourne Hospital and head of the department of infectious diseases at the Peter MacCallum Cancer Centre in Melbourne, Australia.

* Karin Thursky is a professor of microbiology at The Peter Doherty Institute for Infection and Immunity, in Melbourne, Australia and director of the National Centre for Antimicrobial Stewardship.

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‘Black fungus’ in Covid-19 patients: What is mucormycosis, symptoms and treatment?

Mucormycosis, a serious fungal infection but otherwise rare, has been observed in a number of Covid-19 patients recently. While there is no major outbreak, the national Covid task force has issued an advisory.

A rare but serious fungal infection, known as mucormycosis and colloquially as “black fungus”, is being detected relatively frequently among Covid-19 patients in some states. The disease often manifests in the skin and also affects the lungs and the brain. With a number of mucormycosis cases detected in Delhi, Maharashtra and Gujarat, experts in the national Covid-19 task force on Sunday issued an evidence-based advisory on the disease.

What is the disease?

Although rare, it is a serious infection. It is caused by a group of moulds known as mucormycetes present naturally in the environment. It mainly affects people who are on medication for health problems that reduces their ability to fight environmental pathogens, say experts from the Covid-19 task force task force.

Sinuses or lungs of such individuals get affected after they inhale fungal spores from the air. Doctors in some states have noted a rise in cases of mucormycosis among people hospitalized or recovering from Covid 19, with some requiring urgent surgery. Usually, mucormycetes does not pose a major threat to those with a healthy immune system.

What happens when one contracts it?

Warning signs include pain and redness around the eyes or nose, with fever, headache, coughing, shortness of breath, bloody vomits, and altered mental status. According to the advisory, infection with mucormycetes should be suspected when there is:

* Sinusitis — nasal blockade or congestion, nasal discharge (blackish/bloody);

* Local pain on the cheek bone, one-sided facial pain, numbness or swelling;

* Blackish discoloration over bridge of nose/palate;

* Loosening of teeth, jaw involvement;

* Blurred or double vision with pain;

* Thrombosis, necrosis, skin lesion;

* Chest pain, pleural effusion, worsening of respiratory symptoms.

Experts advise that one should not count all cases of blocked nose as cases of bacterial sinusitis, particularly in the context of immunosuppression and/or Covid-19 patients on immunomodulators. Do not hesitate to seek aggressive investigations for detecting fungal infection, they advise.

What’s the treatment?

While it is treated with antifungals, mucormycosis may eventually require surgery. Doctors have said that it is of utmost importance to control diabetes, reduce steroid use, and discontinue immunomodulating drugs. To maintain adequate systemic hydration, the treatment includes infusion of normal saline (IV) before infusion of amphotericin B and antifungal therapy, for at least 4-6 weeks.

Experts in the task force have stressed the need to control hyperglycemia , and monitor blood glucose level after discharge following Covid-19 treatment, and also in diabetics. One should use steroids judiciously — correct timing, correct dose and duration are important.

Management of Covid patients with mucormycosis is a team effort involving microbiologists, internal medicine specialists, intensivist neurologist, ENT specialists, ophthalmologists, dentists, surgeons (maxillofacial/plastic) and others.

Life after surgery for mucormycosis

Mucormycosis can lead to loss of the upper jaw and sometimes even the eye. “Patients would need to come to terms with loss of function due to a missing jaw — difficulty with chewing, swallowing, facial aesthetics and loss of self-esteem, doctors say. Be it the eye or upper jaw, these can be replaced with appropriate artificial substitutes or prostheses. While prosthetic replacement of the missing facial structures can commence once the patient stabilises after surgery, doctors it is important to reassure him about the availability of such interventions instead of leaving him to panic with the sudden unforeseen loss, augmenting a post-Covid stress disorder which is already a reality,” said Dr B Srinivasan, a maxillofacial prosthodontist. “Prosthetic reconstruction can be effected after surgery, but interim solutions should be planned even before surgery of the jaws for better long-term outcomes. Prosthetic reconstruction can ensure that the cure is not more dreadful than the disease itself,” he said.

How can one prevent it?

One should remember that it is a rare disease. However, some groups of people are more vulnerable than others. What predisposes patients is uncontrolled diabetes mellitus, immunosuppression by steroids, prolonged ICU stay, and comorbidities — post transplant/malignancy, voriconazole therapy.

Experts advise that you use masks if you are visiting dusty construction sites. Wear shoes, long trousers, long-sleeved shirts and gloves while handling soil (gardening), moss or manure. Maintain personal hygiene including a thorough scrub bath.

How frequently are cases being detected?

While cases are on the rise, there has been no major outbreak. Niti Aayog member (health) Dr V K Paul said at a media briefing that there has been no major outbreak and they were monitoring cases being reported.

In Maharashtra, Dr Tatyarao Lahane, head of the Directorate of Medical Education and Research, has said that cases of mucormycosis are on the rise. “Traditionally we see a case every few months, usually in very poorly controlled diabetic and immunocompromised patients,” said Dr Parikshit Gogate, consulting ophthalmologist at Ruby Hall Clinic, Pune. “But in the past 2 to 3 weeks, I have seen almost 25-30 of them, mostly in Ruby Hall, some in D Y Patil Hospital.”

Mucormycosis developing in post Covid-19 setting breaks the back of a patient’s family that is barely recovering from this viral infection , infectious diseases consultant in Pune Dr Rajeev Soman wrote in the Journal of Association of Physicians of India in January this year.

Dr Soman is one of the expert members who drafted the advisory as part of the national Covid-19 task force. The also task force includes Dr Arunaloke Chakraborti, Head of the Department of Medical Microbiology, PGIMER, Chandigarh; Dr Atul Patel, infectious diseases specialist, Ahmedabad; and several others.

Patients most vulnerable to mucormycosis are those who have been treated with steroids and other drugs for Covid 19 to reduce inflammation. Efforts are underway to collect data for large studies being done by the Fungal Infections Study Forum and Clinical infectious Diseases Society, Dr Soman said.

What is mucormycosis?

Mucormycosis, commonly called black fungus, is a rare but serious fungal infection caused by a kind of fungus called mucormycete, which is abundant in the environment. It mainly affects people who have health problems or take medicines that lower the body’s ability to fight germs and sickness.

Symptoms

These include pain and redness around eyes and/or nose, fever, headache, coughing, shortness of breath, bloody vomits, and altered mental status. Warning signs can include toothache, loosening of teeth, blurred or double vision with pain.

Who is vulnerable

Vulnerable groups include people who have health problems or take medicines that lower the body’s ability to fight germs and sickness. These include those with diabetes, cancer, or those who have had an organ transplant.

Prevention

Use masks if you are visiting dusty construction sites. Wear shoes, long trousers, long-sleeved shirts and gloves while gardening. Maintain personal hygiene including a thorough scrub bath.

Diagnosis

It depends on the location of the suspected infection. A sample of fluid from your respiratory system may be collected for testing in the lab; otherwise a tissue biopsy or a CT scan of your lungs, sinuses etc may be conducted.

Treatment

Mucormycosis needs to be treated with prescription antifungal medicine. In some cases, it can require surgery; it can lead to eventual loss of the upper jaw and sometimes even an eye.

What is mucormycosis or black fungus?

Hospitals across India have been reporting several cases of Mucormycosis, a rare fungal infection, affecting patients who have recently recovered from COVID-19.

Mucormycosis or black fungus is an aggressive and invasive fungal infection caused by a group of molds called mucormycetes. It can affect various organs but is currently manifesting as an invasive rhino-orbito-cerebral disease, affecting the ear, nose, throat, and mouth. It is not contagious but can cause a lot of damage internally and can be fatal if not detected early.The common name 'black fungus’ is in reference to the blackening that is characteristic of the disease.

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What makes the black infection so deadly?

Black fungus infection has officially been declared an epidemic in Rajasthan and several other states are recording an unproportionate number of cases, most of them linked to COVID complications.

Now, while fungal infections aren't exactly rare or new like COVID-19, the precedence of cases has gone high in recent times. The infection seems to be most impactful for those suffering from severe COVID-19 patients and making those recovered from COVID-19 to land up in hospitals yet again, with odd facial deformities.

Dr Mridul K Daga, Professor and Intensivist, Maulana Azad Medical College, New Delhi shares, “In pre COVID times too, we used to see 1-2 cases in intensive care but now we have been hearing about many more cases though it isn’t as common in Delhi as certain other parts of the country.”

What exactly is the black fungus infection?

Black fungus infection, or the lethal mucormycosis, is caused by a group of moulds called 'mucormycetes', which is present in the air and causes complications when an ill patient inhales these, which then spreads into the sinus cavities, lungs and chest cavities.

Who faces the highest risk?

As per ICMR guidelines, patients with comorbidities, or those taking medications that suppress their immunity to fight off environmental pathogens are most likely to be susceptible to the ills of black fungus.

It has also been likened that COVID-19 patients who are put on prolonged oxygenation support are also at risk to face mucormycosis infection- poor contaminated water resources used for the production of medical oxygen, environmental factors could all be to blame.

There have also been concerns that the disease is the most dangerous for COVID-19 patients battling severe diabetes. Not only do uncontrolled blood sugar levels make it easier for patients to contract severe illness, but poor blood glucose control also makes it an easier surface for fungi to thrive, and spread symptoms.

Dr Sunil Kumar, Director General Health Services, India also adds that the fungi has the potential to thrive and cause damage under unsanitary conditions, "Moisture in the environment, unclean environment in which patients are treated and oxygenated can be a big source of infection. The organism lives with us and act up when we are immunocompromised,” adding that the problem, which existed regionally, has now doubled up. India alone has accounted for over 71% of black fungus casualties this year.

What are the symptoms one needs to be careful of?

Black fungus carries a high mortality rate of 50%. However, if the disease is diagnosed in time, it can be treated well. According to doctors, the disease primarily infects the face, which is referred to as 'rhino-orbital-cerebral mucormycosis' and may even cause distinct facial deformities, associated with the disease. Apart from that, the disease may also affect the sinus passage and cause acute swelling and inflammation. Here are some distinct symptoms which patients should be on the lookout for:

Black crusts around the nose

Facial deformity is the most talked about symptom of the disease. Mucormycosis can prove to be quite dangerous if left untreated, and mutilate a patient's nose, jaw or alter the vital facial structure. The formation of black crusts, swelling in and around the nasal passage and the eyes is a peculiar feature. In many severe cases, surgeries maybe even required to remove jaw bone or the nose.

Headaches and swelling in/and around the forehead

One of the most severe complications with black fungus happens when it spreads to the brain and causes nervous inflammation. Acute headaches, swelling, redness, pain in the forehead could be the earliest signs. Doctors also warn that the infection can impair cognitive function, and critical symptoms, such as memory loss, delirium and changes in one's mental state also need attention at the earliest.

Swelling in the cheeks, eyes or parts of the face

Swelling, local pain on the cheekbone, or experiencing one-sided facial pain or sort of numbness could also be primary markers of the infection right now. Apart from swelling, the fungal infection could also affect skin health and give rise to multiple lesions, necrosis like symptoms.

Vision loss/ partial blindness

Black fungus infection can badly impact the vital nerves in the body and cause ocular damage as well. Some patients report undergoing symptoms like itchiness, redness in the eyes, eye pain, partial blindness and loss of vision. In some cases, the infection can also lead to permanent loss of vision.

Pulmonary infections

Since the moulds can be inhaled by the patient, the fungus growth can spread sporadically across the respiratory passage and affect the lungs, causing severe symptoms. This is what doctors refer to as 'pulmonary mucormycosis'.

Pulmonary complications can start off as nosebleeds, nasal blockage, cause a reduction in facial sensation. Cough, fever, chest pain, which are also some respiratory symptoms associated with COVID-19 can also be seen with mucormycosis.

COVID-19 and Black Fungus

 

COVID-19 and Black Fungus

Many people recovering from COVID-19 have of late been afflicted by black fungus – or mucormycosis – disease. The fungus invades the sinus and makes its way into the intraorbital and intracranial regions. If its progression is not checked early, 50-80% of patients could die.

Both authors are plant biologists interested in fungi. When we first heard of mucormycosis sometime last year, from reports from Europe, it rang a bell.

People experience fungi most often in their kitchens, when fruits rot or the bread turns moldy. Fungi evolved 400 million years ago and play an important role on Earth. They have helped plants move from their aquatic habitats to land, and still help them obtain minerals from the soil. Fungi decompose organic litter and recycle the nutrients locked up in the leaves and wood.

Some of them have also evolved to become plant pathogens: they infect plants, multiply and disperse to other plants, leaving destruction in their wake. The great Irish famine of 1845 that left a million people dead was the work of the fungus Phytophthora infestans, which wiped out the country’s staple potato crop.

While fungal diseases are common among plants, only a very small fraction of them assail humans. One reason is that animals, including humans, have evolved intricate immune systems.

However, when the immune system has been breached by another illness, fungi that are otherwise harmless take advantage and invade human tissues. These are called opportunistic infections. Even so, unlike their pathogenic bacterial counterparts, fungi rarely cause life-threatening diseases. A few fungi, like the Candida yeast, can sometimes kick off a serious infection. Candida lives on the skin and inside the mouth, throat and vagina of healthy persons without causing any problems. But if the host’s body has been weakened by another disease or drugs, it can cause oral thrush, diaper rash and vaginal infections.

The Mucoralean fungi are even less problematic. They include the genuses of Mucor and Rhizopus. These are ubiquitous molds occurring in the soil, compost, animal dung, rotting wood and plant material. You may have seen them as the black growth on old fruits and bread. Mucoralean fungi are generally the first colonisers of dead or decaying plant material. They rapidly utilise the limited amount of simple carbohydrates available before other fungi show up for the more complex carbohydrates, such as cellulose.

Like most fungi, Mucor produces millions of microscopic spherical, dark-hued structures called spores, which are dispersed in air. When the spores land on moist surfaces, like soil or plant material, they begin to germinate and produce thread like structures called mycelia. The mycelia branch out and feed on sugars in their surroundings and grow.

Fungal spores measure one thousandth to one hundredth of a millimeter. The density of the spores – the number of spores per cubic metre of atmosphere – varies depending on the fungus, the location (vegetation and exposed earth) and season. In tropical areas like in India, spore counts are generally higher during the summer than during the monsoons. But compared to the 1,000-5,000 spores per cubic meter outdoors, the count inside homes is typically 100-250 only. Five to 10 species account for more than 90% of the total spore density in the air.

As it happens, hospitals are not free from these spores. A study in Tehran in 2014 suggested that hospital air could carry many opportunistic pathogenic fungi like Candida, Aspergillus, Penicillium and Rhizopus.

When a patient whose immune system has been compromised inhales Mucor spores, they may develop mucormycosis. This is a rare, non-contagious disease – but it can be debilitating or fatal if not treated quickly. The frequency of mucormycosis infections has increased in the last decade, principally because of the greater number of organ transplants. People who have received transplanted organs depend on immunosuppressant drugs to keep their bodies from rejecting the new organs, but in this state they are also predisposed to infection.

People suffering from COVID-19, HIV/AIDS and other viral diseases, congenital bone marrow disease, severe burns, cancers and untreated or irregularly treated diabetes have reduced immunity and are prone to developing mucormycosis. COVID-19 patients who have received steroids are particularly at risk because steroids suppress the immune system. This is why steroids should not be used unless absolutely necessary.

Experiments with rats and rabbits have found that the inhaled spores in healthy animals are quickly killed by white blood cells. But if the host’s immune response has been suppressed, the body produces fewer white blood cells. In this condition, the spores germinate and grow rapidly as thin, wire-like tubes that branch out and enter the blood vessels and kill them.

When Mucor attacks the sinuses, it spreads to the lungs, the brain and the central nervous system. Common symptoms of the resulting mucormycosis include fever, headache, reddish and swollen skin near the nose or eyes, facial pain, cough producing bloody or dark fluids, and shortness of breath. Doctors can diagnose it through a tissue biopsy and an X-ray scan of the lungs.

The two drugs most effective at treating mucormycosis are amphotericin B and posaconazole – provided the infection is found early. However, the latter is hard to do because we don’t know of a reliable diagnostic feature of mucormycosis.

This said, there are a few simple steps we can follow to lower our risk of contracting mucormycosis. The first is to educate society about the disease. Second: we must periodically sample the air in hospitals, especially in the critical care wards, to check for the presence of spores. Third: we must ensure that the humidifiers used during oxygen therapy are sterile. Fourth: recovering patients should be advised to remain indoors until they regain their natural strength and immunity. Fifth: patients engaged in farming or gardening should be advised to lay off from work until the storm has settled.

T.S. Suryanarayanan is at the Vivekananda Institute of Tropical Mycology (VINSTROM), Chennai. R. Uma Shaanker is with the University of Agricultural Sciences, Bengaluru.

 

New nanoimmunoassay can detect anti–SARS-CoV-2 antibodies in ultralow-volume blood samples

The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been the largest global public health crisis in recent memory. To date, it has been responsible for over 158.3 million infections and over 3.3 million deaths the world over.

Managing this crisis, mitigating viral spread, and planning to prepare for the next phase of the pandemic involves numerous testing and analysis regimes. Continuous monitoring of the virus spread to control the disease, the efficacy of vaccines in trials, current infection fatality rates and the health status post-vaccination, call for a large sampling of blood and tests to detect the seroprevalence of SARS-CoV-2.

In a recent study, researchers developed and validated a nanoimmunoassay (NIA) that analyzes 1,024 samples in parallel on a single microfluidic device the size of a USB stick. They detected anti-SARS-CoV-2 IgG antibodies, achieving a sensitivity of 98% and specificity of 100% based on an analysis of 134 pre-pandemic sera (collected in 2013/2014 and 2018) and 155 sera from reverse transcription-polymerase chain reaction (RT-PCR) confirmed COVID-19 positive individuals. 

The results from the study indicated that an accurate binary classification of serum samples could be achieved with NIA. The study involves a detailed development and validation of the NIA method and a rigorous analysis and testing of ultralow-volume whole blood collection.

In this study, the researchers analyzed samples obtained more than 20-day post-onset of symptoms, and also for samples obtained less than 20-day past onset of symptoms – in both cases, the NIA results performed excellently. They demonstrated that NIA could be used to detect anti–SARS-CoV-2 antibodies in ultra low-volume dried whole blood samples (eliminating the need for venipuncture blood collection).

The platform capabilities can be expanded to include multiplexed analysis, allowing four or more biomarkers – multiple antigens, cytokines, or inflammatory markers – to be tested for each sample to gain insights into the viral infection and response.

Consumables, reagent consumption, and associated costs are negligible with NIA, which is an important consideration when compared to the high reagent cost of ELISAs and when considering potential reagent shortages that may be encountered during critical phases in a global pandemic.”

The current testing methods, such as ELISA, chemiluminescent immunoassays (CLIA), or Lateral flow assays (LFAs), require venipuncture for blood collection, followed by sample pretreatment, and involve costly reagents and testing procedures; all of which precludes comprehensive testing and contributes to high healthcare costs. The main advantages presented here are that this assay relies on a repurposed blood from a glucose test strip (finger prick) and other low-cost blood sampling methods to eliminate the need for venipuncture, and is capable of analyzing up to 1,024 samples per device. Also, the NIA reagent consumption and corresponding costs are roughly 1,000 times lower than standard enzyme-linked immunosorbent assays (ELISA).

To implement this method, the researchers explained that laboratories require a commercially available contact microarrayer, and the ability to fabricate masks, molds, and PDMS microfluidic devices, which can be fabricated easily using a spin coater, 80°C ovens, and stereomicroscope. The device readout is performed on a standard epifluorescence microscope equipped with an automated stage.

The researchers tested two commercial blood collection devices: Neoteryx’s Mitra® and DBS System SA’s HemaXisTM DB10, to show the possibility to repurpose low-cost and widely available blood glucose test strips for sample collection and shipment. Samples could be stored up to 6 d at room temperature with minimal sample degradation. The researcher demonstrated that all three methods combined with NIA identified more positive samples than a standard ELISA performed on serum samples collected from the same individuals.

The researchers foresee that an individual can purchase a simple blood sampling kit containing a lancet, a blood sampling device, and a return mail envelope at a local pharmacy or supermarket. Then, the individual can collect the blood with a simple finger prick, and send the device with the blood sample to a laboratory which will analyze for one or more biomarkers, interpret the data, and return the test results to the individual via electronic communication.

The method in this study can be used to analyze large samples collected as part of epidemiological studies, identifying donors for plasma therapy as well as offering vaccine trial support. During a global pandemic, such technologies could enable the collection of critical epidemiological data, providing instrumental data for vaccine development and vaccine rollout, the researchers write.

The combination of a high-throughput, highly specific and sensitive NIA and the ability to analyze minute volumes of dried blood samples have enormous potential for SARS-CoV-2 serology, epidemiological studies, vaccine trial, and therapeutic development support.”

Journal reference:

• Zoe Swank, Grégoire Michielin, Hon Ming Yip, Patrick Cohen, Diego O. Andrey, Nicolas Vuilleumier, Laurent Kaiser, Isabella Eckerle, Benjamin Meyer, Sebastian J. Maerkl. A high-throughput microfluidic nanoimmunoassay for detecting anti–SARS-CoV-2 antibodies in serum or ultralow-volume blood samples. Proceedings of the National Academy of Sciences. May 2021, 118 (18) e2025289118;  https://www.pnas.org/content/118/18/e2025289118

Black fungus complicates India's COVID pandemic

India faces a global health crisis as the number of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections reaches over 23.7 million. As the country's health system buckles with increased admissions and a lack of resources, another health threat has emerged.

Public health officials report a rare black fungus infection, called mucormycosis, which is increasingly seen in vulnerable patients, including those with COVID-19 disease.

What is mucormycosis?

Mucormycosis is a very serious and potentially fatal infection caused by exposure to mucor mold. Mucor is a microbial genus of approximately 40 species of molds commonly found in soil, plants, decaying fruits and vegetables, and manure.

The fungal infection commonly affects the sinuses of the lungs after inhaling fungal spores from the air. The fungi can also enter the skin after a cut, burn, or skin injury.

The mortality rate of this infection is about 50 percent. It impacts high-risk populations due to their reduced immune system function, including those with diabetes, cancer, and human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS).

Mucormycosis may cause symptoms like coughing out blood, blackening over the nose, blurred vision, chest pain, and breathing difficulties. A classic feature of this infection is tissue necrosis or tissue death. If the fungus spreads to the eyes, the patient may develop blurred vision, drooping eyelids, swelling, and possible vision loss.

The fungal infection is not contagious and does not spread between people and animals. There is no vaccine to prevent the infection.

India and the fungal infection

The black fungus impacts the health of people with comorbidities, like diabetes and weakened immune systems. One of the ways COVID-19 is being treated is through high-dose steroids to treat inflammation. However, the drug can suppress the immune system, making it easier for other pathogens to take advantage.India sees an increase in mucormycosis cases, partly because many people grapple with SARS-CoV-2 infection. The COVID-19 pandemic created conditions for the infection to thrive and spread. The immune system of residents is compromised by SARS-CoV-2, allowing the black fungi to take hold.

As two infections continue to wreak havoc, India's health care system is on the brink of collapse.

In the western state of Maharashtra, including Mumbai, doctors report that around 200 patients who had recovered from COVID-19 were being treated for mucormycosis. Of these patients, eight died.

Meanwhile, in Gujarat, the local government ordered the allocation of separate wards in hospitals. Further, the officials ordered 5,000 doses of amphotericin B, the drug used to treat the fungal infection. New Delhi also reported cases of mucormycosis.

India has not released national data on the new infections but said there is no major outbreak.

Threat for diabetics

Mucormycosis may become potentially fatal in some individuals, including diabetics. The fungal infection is known to attack people who have compromised immune systems, especially those with diabetes.

People who have diabetes have weakened immune systems, making it easier for the fungi to cause infection. Apart from this, diabetics are at a higher risk of mucormycosis since the fungi love iron-rich, acidic environments, and diabetic ketoacidosis, a condition in diabetics that causes the blood to become acidic.

How to prevent mucormycosis infection?

Due to its increased fatality rate, people should be proactive in protecting themselves. They should avoid areas with dust, including excavation and construction sites. Avoid contact with water-damaged buildings and floodwater and prevent joining activities that involve close contact with soil and dust. When handling soil, make sure to use protective gloves and wash the hands with soap and water.

In treating fungal infection, patients need to receive treatment promptly. Usually, antifungal drugs will be given to kill the fungi.

Sources:

• U.S. Centers for Disease Control and Prevention (CDC). (2021). People at Risk & Prevention. https://www.cdc.gov/fungal/diseases/mucormycosis/risk-prevention.html
• 'Black fungus' complication adds to India's COVID https://www.reuters.com/world/india/black-fungus-complication-adds-indias-covid-woes-2021-05-10/
• Thomas, Liji. 2020. Analysis of India's battle with COVID-19. News-Medical, 2020, https://www.news-medical.net/news/20200504/Analysis-of-Indias-battle-with-COVID-19.aspx.