Introduction

India reported 31 million cases of Coronavirus Disease 2019 (COVID-19) as of July 17, 2021, trailing only behind the United States (US) with about 3 million cases [1]. An estimated 448,000 COVID-19 deaths are projected in the country by November 1, 2021 [2]. The Ministry of Health and Family Welfare (Government of India [GoI]) regularly issues travel and health advisories, provides guidance and inspiration to the healthcare community, sets up pandemic management taskforces, establishes helplines, enables mhealth surveillance (Arogya Setu app), opens counselling centres, and creates awareness materials for the public [3]. Despite all these efforts, the second wave that began in early 2021 was very upsetting, as people struggled to hospitalise infected patients, access oxygen supply, and handle the bodies of deceased patients. The largest cities of North India witnessed queues of ambulances with critically ill patients and a shortage of cremation facilities in graveyards, leading to open cremation on street sidewalks [4–6]. Insufficient pandemic mitigation and superspreader mass gatherings of religious and political interests are believed to have caused the worst COVID-19 surge [7,8].

The common COVID-19 manifestations, as observed in a study of over 136,000 cases during the initial months of infection spread in India, included high fever (88%), dry cough (67.7%), fatigue (38.1%), dyspnoea (18.6%), and muscle pain (14.8%), while 7.1% patients were asymptomatic [9]. A very recent (July 15, 2021) study reported an international cohort (n = 3,762) spanning 56 countries with confirmed or suspected “Long COVID,” a condition with a majority recovered only after 35 weeks since onset. The authors assessed the prevalence of over 200 symptoms affecting 10 bodily systems and revealed that the mean number of symptoms per patient was 55.9 (±25.5) [10]. Researchers warn that the impact of COVID-19 has been greatly neglected as patients continue to develop multisystemic manifestations for more than 7 months [10]. COVID-19 deteriorates immune status of patients, paves the way for opportunistic and secondary infections, and worsens preexisting clinical conditions [10,11].

The surge in COVID-19–associated mucormycosis

Across borders, patients with COVID-19 experience notorious fungal coinfections during or after weeks or months of recovery. COVID-19–associated mucormycosis (CAM) has been reported in many countries like Austria, Brazil, Egypt, France, India, Iran, Italy, and the US [11,12]. A recent systematic review observed that CAM constitutes 0.3% of COVID-19 coinfections [13]. Mucormycosis is not unfamiliar to India; the case rate before 2019 was almost 70 times higher than in developed countries. The disease prevalence in India is predicted to be 140 cases per million population [8,14]. While India faces tough times during the second wave of COVID-19, there is a recent unexpected surge in CAM cases. As a result, GoI has declared it a notifiable disease, while several state governments have declared it an epidemic [8]. Various control measures and guidance on procuring and allocating treatment drugs to all states were taken up quickly [15].

COVID-19–associated rhino-orbital-cerebral mucormycosis (CAROCM) is the most common type observed during the current epidemic, followed by the pulmonary form [16,17]. Prior to the COVID-19 pandemic, the mucormycosis mortality was 50%. However, during the current pandemic situation in India, it has increased to 85%, mainly due to crowded hospitals, unavailability of healthcare resources, overburdened healthcare workers, and poor diagnostic quality [18]. Notably, a recent systematic review of 7 global CAM cases observed 100% mortality, though 43% of them received antifungal monotherapy [19]. For India, a low doctor/patient ratio and practising by unqualified or nonregistered healthcare professionals are other key hurdles that the country faces to tackle CAM [20]. Lack of awareness and inadequate health infrastructure have introduced additional burden [16]. Globally, at least 6 systematic literature reviews are available on CAM, as of July 19, 2021. The majority of publications are from India (n = 4) [21–24]; the largest review has included 82 cases [24]. Besides, newer observational studies and case series have emerged. An Indian multicentric epidemiological study reported a 2-fold increase in mucormycosis cases year-over-year (2019 versus 2020). The CAM prevalence was 0.27% among hospitalised patients [25]. An in-press editorial from the Indian Journal of Medical Microbiology claims that a GoI website has mentioned more than 31,000 CAM cases by June 13, 2021 [16]. By July 2021, the case count reached 40,000 [26].

Extensive discussions and strategic actions are being promulgated from political, administrative, regulatory, and healthcare flagbearers during this unprecedented time as the country faces an epidemic within a ravaging pandemic. Recently, a staging system for CAROCM has been proposed, and a dedicated registry for CAM has been started. The present critical review, which stands out from the limited reviews available as of July 19, 2021, attempts to comprehensively analyse recent evidence on CAM pathogenesis and its potential risk factors and intends to throw light on several India-specific treatment guidelines. We searched leading databases like PubMed, Web of Science, Ovid, Scopus, and Google Scholar for scholarly literature on CAM surge in India published until July 19, 2021, in English using the relevant keywords (“mucor*” OR “zygomycosis;” “COVID” OR “SARS-CoV” OR “coronavirus;” and “India”). Besides, we conducted a Google web search for CAM and COVID-19 statistics and potentially relevant news reports published before the above data cutoff period. We also reviewed the official websites of professional societies like the “Indian Medical Association” and governmental portals like the “Directorate General of Health Services–India” before the said date for any essential treatment and management guidelines. Later in September 2021, we had modified the post-submission manuscript based on the peer review comments and updated it with the recent references suggested by the reviewers.

Causes, characteristics, and diagnosis

Mucormycosis is caused by various saprophytic fungi in the order Mucorales, including Rhizopus, Lichtheimia, Mucor, and Rhizomucor species, and the first 3 species account for three-fourths of all cases [27]. It is an opportunistic infection affecting the lungs, skin, gut, rhino-cerebral areas, and central nervous system (CNS) and presents a clinical condition specific to the organ system. It may also be present in a disseminated form [28]; postmortem analysis in a few patients with disseminated disease revealed that they did not receive systemic or surgical treatment [19]. Rhizopus arrhizus (previously named Rhizopus oryzae) is the most common causative agent globally, although the fungi responsible for infection differ between geographies. In India, Apophysomyces is the second most familiar species causing mucormycosis [29]. Apophysomyces elegans and Rhizopus homothallicus are commonly reported fungi in this region, while other uncommon ones, including Mucor irregularis and Thamnostylum lucknowense, have also been observed. This deep fungal infection is wrongly termed a black fungus by local media and even by some learned academic researchers by confusing dematiaceous fungi with those that cause mucormycosis [30,31]. A unique form of isolated renal mucormycosis has also been reported in India [32,33].

Mucormycosis is not contagious. The entry of infective spores present in the environment into the human body is by inhaling, ingesting or direct inoculation through wounds, and germinating into angioinvasive hyphae [19,31]. The most extensive observational study reported on CAROCM in India, as of July 19, 2021, included 2,826 patients from 22 states. This research, named COSMIC, conducted jointly by the Oculoplastic Association of India and the Indian Journal of Opthalmology, described the epidemiological features and clinical characteristics along with details of predisposing factors for developing CAROCM and presenting various management strategies and their reported outcomes. The most common CAROCM symptoms observed in that study included orbital/facial pain (23%) and oedema (21%), vision loss (19%), ptosis (11%), and nasal congestion (9%); the primary signs included periocular/facial oedema (33%), vision loss (21%), proptosis (11%), and nasal discharge (10%) [34]. Pulmonary mucormycosis mimics the symptoms of COVID-19, such as pyrexia, cough, and dyspnea [18].

The initial features of CAROCM appear in the paranasal sinuses before extending to the orbit and the cranial cavity. CAROCM can be suspected in patients with signs and symptoms as observed in the COSMIC study, along with the presence of necrotic ulcers in the nasal cavity/palate and orbital apex syndrome and cavernous sinus syndrome [34,35]. Mucormycosis involving the ear may have the characteristics of otitis externa, and the usual antibacterial therapy does not resolve the otological symptoms [36]. Double- and triple-mutant variants of SARS-CoV-2 have emerged in India during the second wave of COVID-19, which are more dreadful and are doubted to play a mightier role in CAM surge [37,38]. A recent systematic review that compared CAM cases of India (n = 233) with that of other countries (n = 42) suggested that pulmonary or disseminated disease form was associated with increased death rate, and treatment (in combination form) could improve survival [39]. Another cohort study identified cerebral involvement, and a higher HbA1c (≥8) level could significantly predict patient survival [40]. Diagnostic confirmation can be obtained by (a) direct microscopy with slides mounted with potassium hydroxide, particularly when it is necessary to start therapy immediately; (b) fungal culture; (c) biopsy of the affected lesions with adequate precaution; (d) radiological (computed tomography of ostiomeatal complex and magnetic resonance imaging with contrast) examinations; and (e) matrix-assisted laser desorption/ionisation time of flight mass spectrometric analysis [35,41–45]. Florid sinusitis and bone erosion may not be identified on radiological examinations at an early stage; therefore, initial findings should not lead to missed diagnosis [42]. REBOVasC checklist may help radiologists not to miss any critical findings in the imaging examination [46]. It focuses on the rhinosinus, extrasinus, bones, orbital, vascular, and CNS areas for infection spread.

How does mucormycosis affect patients with COVID-19?

There are 3 possible theories for CAM related to immune and inflammatory processes: (1) COVID-19 causes significant lymphopenia, resulting in a dramatic reduction in the availability of T cells (CD4+ and CD8+) and opening the entry gate for opportunistic fungal infections; (2) increased pro-inflammatory markers in patients with severe disease; and (3) pronounced damage of pulmonary tissues by COVID-19 aids the invasive fungi, especially the airborne ones or those that attack through the respiratory system [47,48]. Hyperferritinemia caused by excess interleukin-6 (IL-6) release and macrophage activation results in increased availability of free iron within cells. This, in turn, causes endothelial destruction and inflammation called endothelitis. In addition, the hepcidin mimetic action of the virus further induces ferritin independent of the inflammatory reaction [17]. Thus, COVID-19–induced immunosuppression increases the risk of opportunistic infection, damages the endothelium and alveoles, easing the port of fungal invasion, and increases the glucose level due to the acute diabetes-like state caused by pancreatic damage; increased ferritin level supports fungal growth, and increased body temperature is optimal for thermotolerant fungi. Another exciting hypothesis revolves around the dysregulation of angiotensin-converting enzyme 2 expression in various bodily organs, immunosuppression, and the creation of a microenvironment system that increases the risk of coinfection in COVID-19 [49]. Up-regulation of 78-kDa glucose-regulated protein (GRP78), a heat shock protein, in patients with COVID-19 (5 times more than controls) due to increased glucose and iron content caused by diabetic ketoacidosis (DKA) or induced by dexamethasone use also facilitates fungal entry. Besides, it promotes Mucorales’ pathogenicity and virulence [17,50].

Identifying risk factors and implementing preventive measures

The systematic review of global CAM (7 cases) reported a male predominance (85.7%), and all patients showed severe disease conditions [19]. Importantly, the COSMIC study enrolled patients from January 2020, i.e., since the beginning of COVID-19 in India. However, the surge in CAM incidences has been observed during the second pandemic wave in 2021. The results identified diabetes as the primary predisposing factor. Another multicentre CAM epidemiological study conducted between September and December 2020 during the first wave has also reported the exact reason for such a steep hike occurred lately. Over 65% of CAM patients (187 of 287 mucormycosis cases) had uncontrolled diabetes [25] and are thus the most significant risk factor for CAM. The phagocytes of immunocompetent hosts have the potential of kill Mucorales spores by producing oxidative metabolites. Uncontrolled hyperglycemia due to DKA can change this immunologic response, leading to reduced granulocyte phagocytosis with a modified polymorphonuclear leukocyte response [51]. Besides, Mucorales possess a ketone reductase enzyme that thrives in high glucose conditions and DKA, resulting in a poor prognosis [52]. India, the home of 1.38 billion people as estimated for 2020 [53], reportedly has 77 million patients with diabetes as of 2018. Diabetes accounts for 3.1% of all deaths [54,55]. Diabetes, when coupled with COVID-19–induced systemic immune change, results in decreased immunity and an increased risk of secondary infections [51,56]. A recent systematic review of 15 studies had confirmed the role of diabetes in CAM [57]. Managing diabetes is thus crucial for controlling both COVID-19 and CAM [58,59].

Another critical risk factor is the inappropriate use of corticosteroids [60]; 71.4% of cases reported in a systematic review had received corticosteroids [19]. In particular, three-quarters of Indian patients in a study conducted during the first wave of COVID-19 received corticosteroids (with more than 60% receiving inappropriate therapy) [25]. In the initial period of the pandemic, the Indian authorities recommended a higher methylprednisolone dose (approximately 70 to 140 mg) for patients with severe and critical COVID-19. This could have affected more immunocompromised patients and made them vulnerable to fungal attack. Later, it was reduced to the World Health Organisation–suggested dose of 32 mg/day. Besides, even the nonsevere patients took corticosteroids out of fear without medical counselling [8,61]. Corticosteroids tend to cause lymphopenia and T lymphocyte dysregulation. They may also induce hyperglycaemia in patients with diabetes [62,63]. In a COVID Care Centre in Western India, 3.36% (32 of 953) patients experienced CAM, while 93% of them had prior corticosteroids exposure [64]. Tocilizumab, an anti-IL-6 receptor monoclonal antibody, is the only immunosuppressant mentioned in the Indian guidelines on the COVID-19 management algorithm for off-label use [65]. Increased use of tocilizumab in patients with COVID-19 for inflammation control can reduce patient immunity and pose a significant risk for contracting CAM [66–68]. The use of an antifungal agent, voriconazole, in Mucorales-related infections does not yield efficacy; instead, it can lead to breakthrough mucormycosis infection.

Similarly, inappropriate use of broad-spectrum antibiotics in patients with COVID-19 may also increase CAM risk [14]. Both broad-spectrum antibiotics and antifungal prophylaxis interrupt the healthy sinonasal microbiome, possibly enabling opportunistic infections. Besides, macrolide antibiotics such as azithromycin also hinder IL-6 and thus disrupt antimicrobial immune response [68]. Notably, a recent clinical study comparing patients with CAM and controls has suggested no clear evidence on the role of zinc supplementation in CAM pathogenesis [69].

Neutropenia, leading to reduced intact immunity, is a risk factor for mucormycosis; thus, immunocompetent individuals do not become affected by it [47]. The unhygienic handling of oxygen or inferior tubing, contaminated masks, an impure water source used in humidifiers, and the use of the same oxygen mask for more than 2 patients for a longer period are also reported to be the causes of concern [66,70]. However, the involvement of humidifier water as the source is debatable. It is noteworthy that the passage of oxygen makes humidifier water agitated, thus preventing Mucorales to produce spores [31]. Since there is increased use of industrial oxygen during this crisis, appropriate handling is crucial for patient safety [14].

Albeit mucormycosis is rare in patients who received organ transplants (2 in 1,000 cases), retransplantation and chronic graft dysfunction are considered risk factors, mainly because of repeated immunosuppressive requirements [71,72]. Environmental factors, including humid climate (tropical/subtropical) and hot weather in several regions within India, may encourage fungal growth and be suitable for disease prevalence. Interestingly, periodic variations in mucormycosis have been observed with respect to weather conditions [32]. The dominance of some Mucorales species, such as Apophysomyces, in Indian soil may further support this hypothesis [73]. The use of cow dung for therapeutic use is also suspected to be a potential factor since animal manure may act as a source of infection [74,75]. Other potential factors that can increase the risk of CAM are shown in Fig 1, while Box 1 lists possible measures that can alleviate the potential risk of CAM.

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Fig 1. Potential risk factors for COVID-19–associated mucormycosis.

https://doi.org/10.1371/journal.pntd.0009921.g001

What do the treatment guidelines recommend?

As of July 19, 2021, at least 11 different India-specific guidance documents or CAM directives are available (Table 1). They mostly follow the 2019 global guidance on mucormycosis by the European Confederation of Medical Mycology (ECMM) and Mycoses Study Group Education and Research Consortium [77]. Code Mucor, the most comprehensive among them, proposes a simple but reliable staging system for CAROCM and a treatment algorithm that suits each substage [76]. In general, most national guidelines warn about controlling diabetes and optimising corticosteroids use. Immediate and extensive radiology-guided surgical intervention is the treatment of choice. Orbital exenteration is suggested for patients in CAROCM stage 3a-c with the worsening of the orbital component within 72 hours. In advanced disease conditions (stage 4), aggressive debridement of the paranasal sinuses with or without turbinectomy or palatal resection or orbital wall resection may be necessary [76]. The India-centric guideline by ECMM and the International Society for Human and Animal Mycology (ISHAM) also advises extensive debridement of external infected tissues, including bones. It suggests repeated procedures in case of recurrence [78]. In the largest sample of 2,826 CAROCM patients, surgery decreased (from 67% to 39%) mortality and disease progression. Moreover, surgical intervention seems not to be contraindicated to CAROCM patients with CNS involvement, as orbital exenteration in all patients with stage 4 disease has shown stable residual or regressed lesions with improved survival after 3 weeks [34]. The Indian Medical Association provides a long list of suggested surgical procedures, including maxillectomy, depending on the need of affected patients [79].

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Table 1. Recommendations on treating CAM in India.

https://doi.org/10.1371/journal.pntd.0009921.t001

All guidelines recommend the use of systemic antifungal agents without any prophylactic therapy. The Indian Council of Medical Research (ICMR) recommends administering antifungal therapy for at least 4 to 6 weeks [43]. Slow infusion of liposomal amphotericin B (AmB, 5 mg/kg/day) is the preferred choice. A higher dose of up to 10 mg/kg/day is suggested if the infection spreads to the CNS [80]. Deoxycholate and lipid complex of AmB are considered alternatives [76]. Pyrexia, acute renal injury, hypokalaemia, increased levels of creatinine in blood, multiorgan dysfunction syndrome, and renal impairment are the leading adverse events (AEs) reported for AmB [85]. Hence, it is essential to assess renal function and potassium level during AmB treatment. In renal impairment, a dose reduction of up to 50% is recommended [83]. In patients contraindicated to AmB, selected azoles are suggested. Isavuconazole or posaconazole are the most preferred second-line drugs for salvage therapy. At the same time, itraconazole is recommended only by the Fungal Infection Study Forum and ECMM/ISHAM when AmB or the primary azoles are not available [78,81]. Therapeutic monitoring is recommended for itraconazole and posaconazole at 5 and 7 days of respective treatments. Mucormycosis in patients with neutropenia or graft-versus-host-disease may be managed with oral fluconazole; oral prophylaxis with itraconazole and voriconazole are suggested [28]. The dose regimens for all systemic anti-CAM agents indicated by different guidelines are detailed in Table 1, while the most common reported AEs are listed in Table 2.

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Table 2. Common AEs of systemic fungal agents used to treat CAM as reported in the US Food and Drugs Administration Adverse Events Reporting System [85].

https://doi.org/10.1371/journal.pntd.0009921.t002

No guidance documents recommend combination therapy, citing the unavailability of supportive evidence, except one. The Himachal Pradesh National Health Mission suggests combining lipid polyenes with echinocandins (caspofungin) or azoles and having a triple regimen with all 3 drug classes included. However, it warns about the need for more extensive studies to prove these beneficial [83]. Calcineurin inhibitors tend to benefit antifungal resistance and virulence, with tacrolimus synergising posaconazole efficacy against R. arrhizus in vitro. Still, clinical effectiveness is not patent, mainly due to the emergence of various mutations and less use of immunosuppressants in these patients [71]. It is imperative to prevent potential drug–drug interactions of antifungals used to treat CAM when used in conjunction with experimental antiviral and immune therapies of COVID-19. Table 3 lists these interactions of specific anti-CAM agents recommended by various guidance documents against a few selected drugs currently used to treat COVID-19 [86]. All 3 guideline-suggested azoles may increase the colchicine and ruxolitinib exposure, while itraconazole-colchicine coadministration should be avoided. The use of AmB with steroids can cause hypokalemia, which requires dose adjustments. It is worthy of mentioning that the treatment choice for CAM is limited. This will create economic difficulties for patients in low-resource settings in countries like India [47].

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Table 3. Potential drug–drug interactions of guidelines-suggested antifungal agents for treating mucormycosis with experimental COVID-19 antiviral or immune therapies [86].

https://doi.org/10.1371/journal.pntd.0009921.t003

ICMR suggests forming a multidisciplinary team comprising microbiologist, internal medicine expert, intensivist, neurology specialist, otorhinolaryngologist, ophthalmologist, dentist, maxillofacial or plastic surgery specialist, and biochemist to manage patients with CAM [43]. All India Institute of Medical Sciences advises segregating patients based on COVID-19 status and suggests evaluating with mucor checklist twice daily [42]. The role of dental surgeons is imperative in the posttreatment phase as the patients may require intensive postoperative care and prosthetic rehabilitation [87,88]. An interesting and noteworthy study was reported from Fortis, a high standard private hospital in Mumbai, having an award-winning antimicrobial stewardship program [89]. During the country’s peak pandemic period (March 2020 to May 2021), 0 CAM cases were recorded among over 5,000 patients hospitalised for COVID-19 treatment. The reasons behind this laudable effort rely on following state government-specified COVID-19 treatment protocol, strict glycaemic control, optimal use of corticosteroids, and monoclonal antibodies.

Future directions

Of the 16 mucormycosis studies registered on ClinicalTrails.gov, only 2 are related to CAM, of which an India-centric study is in the enrollment stage [90]. This project is expected to offer evidence on CAM features that currently wreak havoc in the country and contribute to the MUNCO registry. MUNCO is a recently launched international database of case reports on mycotic infections in COVID-19 [91]. The form that is used to register CAM cases contains key reporter (physician) information, patient details (without identifying information), case history related to COVID-19 and CAM, hospitalisation and treatment details, risk factors, COVID-19 vaccination, and impact of CAM on body systems [92]. Similarly, it would also be interesting to see how much CAM data goes into FungiScope, an established global registry for fungal infections [93]. This registry accepts case entry through ClinicalSurveys.net, while data can be searched on the FungiQuest retrieval page [94]. The other ClinicalTrials.gov study is from France. This completed study involved the characterisation of opportunistic fungal coinfections (including CAM) in mechanically ventilated patients with COVID-19 in ICU settings. As of September 03, 2020, 576 patients were enrolled, and the study results have not yet been published [95].

Novel therapies and treatment approaches are being explored to counter mucormycosis. The potential benefit of introducing statins into CAM therapy is recently proposed [96]. The authors suggest that statins may induce cytoprotective GRP78 expression, decrease infection risk, and synergise the anti-CAM drug levels in plasma. In vitro studies of statins showed positive results for various fungi; lovastatin could cause apoptosis of Mucor racemosus, while fluvastatin and rosuvastatin were beneficial against Rhizomucor and Rhizopus species. Interestingly, combination therapy of AmB + atorvastatin/lovastatin performed better against R. arrhizus than the efficacy produced by AmB alone [97]. This modality may also be clinically beneficial in high-risk patients with diabetes and hypercholesterolemia, but more extensive clinical trials are needed to prove its worthiness. Many other genetic and preclinical approaches are also being experimented. Mucorales peptides CotH3 and CotH7 have recently been identified to be associated with endothelial invasion of Rhizopus species. Anti-CotH3 antibodies are found to protect mice with neutropenia and DKA [98], while anti-integrin β1 antibodies restrict Rhizopus delemar attack of alveolar epithelial cells and guard mice with DKA from pulmonary mucormycosis [99]. Drugs under preclinical investigation that have the potential to become anti-Mucorale agents include VT-1161, SCH 42427, APX001A, colistin, and PC1244. Exploring novel treatment approaches, including the choice of using different routes for AmB administration (nebulised aerosols and topical application), is also being researched [100]. Interestingly, Indian researchers have come up with an innovative computer-aided customisable implant for the zygomatic portion of patients with mucormycosis. The implant, printed by metal laser sintering, could optimise the facial appearance and improve patient quality of life [101].

Immediate action should be taken to curtail COVID-19 and CAM, infections that currently ravage India, to prevent further spread. To achieve this, several fundamental steps, such as using the correct terminology to define the disease and transparency in reporting cases across regions, must be initiated. Since CAM is not transmitted between humans, no tracking like COVID-19 is required; however, the actual incidence would help plan appropriate health resource utilisation and prevention strategies. A further surge in CAM can be avoided by identifying high-risk groups and managing uncontrolled diabetes, which is the easiest to do among various potential risk factors. However, in India, since the large population lives in a rural area with many in poor resource settings, monitoring diabetes by testing blood sugar may not be a viable economical option. Therefore, the idea of Mass Urine Sugar Testing to Assess and Regulate Diabetes (MUSTARD) may come to the rescue. Urine-based testing is less costly (5 US cents), quick, and easy to perform among the masses [20]. Penultimately, mass vaccination is the stepping stone to achieving immunity to COVID-19, while mass surveillance is crucial to tackling CAM. As of July 15, 2021, 391 million doses of the COVID-19 vaccine were administered in the country [3]. Governmental agencies currently run massive campaigns to prevent vaccine hesitancy, and the results are promising as there is an increase in the number of vaccinated populations. Finally, it will be appropriate to observe the characteristics in Indian patients with “Long COVID” coinfected with CAM.

Acknowledgments

The figure was created using biorender.com platform.