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American Journal of  Medical 
Science and Innovation (AJMSI) 

Understanding COVID-19 Pandemic, Impaired Smelling (anosmia) Incidence and
Outcome among Patients in Dubai: Retrospective Study

Fateh Almohammad Alsalem1*

Volume 4 Issue 1, Year 2025
ISSN: 2836-8509 (Online)

DOI: https://doi.org/10.54536/ajmsi.v4i1.2979
https://journals.e-palli.com/home/index.php/ajmsi

Article Information ABSTRACT

Received: August 02, 2024

Accepted: September 04, 2024

Published: February 08, 2025

The onset of  anosmia, or temporary loss of  smell, has emerged as a prominent neurological 
manifestation and an early indicator of  COVID-19 infection. This retrospective study, 
conducted by the Dubai Health Authority (DHA) staff  at the DHA COVID-19 Command 
& Control Center in Dubai – UAE, from May to July 2020, aimed to investigate the 
prevalence and characteristics of  anosmia in COVID-19 patients. A total of  1075 patients 
were enrolled in the study, comprising 878 males (81.4%) and 201 females (18.6%). The 
median age ranged from 31 to 40 years. Patients with anosmia were compared to those 
without, with a particular focus on gender disparities and associated comorbidities, including 
diabetes, hypertension, heart disease, lung disease, and thyroid disease. The study found 
that 22% of  COVID-19 patients presented with anosmia, the initial symptom in 47% of  
cases. Notably, 95% of  patients experiencing anosmia recovered within two months. While 
there was no significant correlation between anosmia and comorbidities, such as diabetes, 
hypertension, heart disease, lung disease, and thyroid disease, there was also no association 
observed between anosmia and other common COVID-19 symptoms, such as fever, cough, 
shortness of  breath, and diarrhoea. Anosmia, occurring in approximately 22% of  COVID-19 
cases, is a noteworthy early indicator of  the infection. Despite its prevalence, anosmia has 
no significant correlation with comorbidities or other symptomatic manifestations of  
COVID-19, which underscores the importance of  recognising anosmia as a distinct clinical 
feature in diagnosing and managing COVID-19.

Keywords
Anosmia, COVID-19, 
Prevalence, Comorbidities, 
Symptoms

1 ENT Department, Dubai Hospital, Dubai, UAE
* Corresponding author’s e-mail: drfatehsalem@gmail.com 

INTRODUCTION
The COVID-19 pandemic, stemming from the 
novel coronavirus (SARS-CoV-2), has presented an 
unprecedented global health crisis since its emergence 
in December 2019. Alongside its well-documented 
respiratory manifestations, COVID-19 has exhibited 
a spectrum of  symptoms, ranging from mild to severe, 
with some patients experiencing atypical presentations. 
Among these symptoms, anosmia, or the temporary loss 
of  smell, has emerged as a distinctive feature, prompting 
further investigation into its prevalence, pathophysiology, 
and clinical implications (Pollard et al., 2020).
Anosmia following viral infections, often called post-
viral olfactory loss, has been recognised in various viral 
illnesses, including influenza and coronaviruses such 
as HCoV-229E. In COVID-19, anosmia has gained 
considerable attention due to its frequency and potential 
diagnostic utility (Rebholz et al., 2020). Previous literature 
has suggested that anosmia may precede other hallmark 
symptoms of  COVID-19, such as fever and cough, and 
may persist as the sole manifestation of  the disease in 
some individuals; this unique association underscores the 
importance of  understanding the mechanisms underlying 
anosmia in COVID-19 patients (Daher et al., 2020).
Recent investigations have shed light on potential 
mechanisms contributing to anosmia in COVID-19. 
Notably, the presence of  angiotensin-converting enzyme 
2 (ACE2) receptors in nasal epithelial cells has been 
implicated in facilitating viral entry and replication 

(Beyerstedt et al., 2021). The nasal cavity serves as an 
accessible site for viral invasion, raising questions about 
the direct effects of  SARS-CoV-2 on olfactory neurons 
and supporting cells. Additionally, the inflammatory 
response triggered by viral infection may contribute 
to olfactory dysfunction through mechanisms such as 
neuroinflammation and cytokine release (Othman et al., 
2022).
Moreover, emerging evidence suggests that the 
pathophysiology of  anosmia in COVID-19 may differ 
from that of  other viral etiologies. Unlike anosmia caused 
by viruses that directly damage the neural epithelium, 
such as certain coronaviruses, COVID-19-induced 
anosmia appears to exhibit a more transient course, with 
many patients experiencing spontaneous recovery within 
weeks. This distinction underscores the need for further 
research to elucidate the mechanisms underlying anosmia 
in COVID-19 and its implications for disease prognosis 
and management (Butowt & von Bartheld, 2021).
This study aims to investigate the incidence, prevalence, 
and outcomes of  anosmia among patients diagnosed with 
COVID-19 in Dubai, UAE. Additionally, the study seeks 
to establish the time of  onset and duration of  symptoms 
related to the loss of  smell and taste in COVID-19 patients. 
By examining these factors, the study aims to contribute 
to a deeper understanding of  the clinical presentation and 
course of  COVID-19 in the context of  anosmia, thereby 
informing diagnostic and management strategies for 
affected individuals in Dubai and potentially beyond.



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Anosmia, defined as the temporary or permanent loss of  
smell, has emerged as a distinctive symptom of  COVID-19 
caused by the novel coronavirus, SARS-CoV-2. This 
phenomenon has garnered significant attention due 
to its high prevalence and potential diagnostic value 
in identifying COVID-19 cases (Ahmed et al., 2022). 
Understanding the epidemiology, pathophysiology, and 
clinical implications of  anosmia in COVID-19 is crucial 
for effective disease management and control efforts.
Anosmia has been reported as one of  the earliest and 
most common symptoms of  COVID-19, often occurring 
before the onset of  other respiratory symptoms (Aanand 
et al., 2022). A study by Altundağ et al. (2020) has indicated 
that anosmia may affect up to 80% of  COVID-19 
patients with varying degrees of  severity (Altundag et 
al., 2021). The prevalence of  anosmia appears to run 
across different populations and geographic regions, 
highlighting the need for comprehensive epidemiological 
studies to elucidate its global burden.
Anosmia has been proposed as a potential predictor 
of  COVID-19 infection, prompting individuals to seek 
testing and medical care. Several studies have suggested 
that anosmia may precede the onset of  other symptoms, 
such as fever and cough, making it a valuable clinical 
marker for early detection of  COVID-19 cases (Avcı 
et al., 2020; Talavera et al., 2020). Including anosmia in 
COVID-19 screening protocols has been advocated 
to improve case identification and facilitate timely 
intervention.
The underlying mechanisms of  anosmia in COVID-19 
are not fully understood but are thought to involve 
viral-induced damage to the olfactory epithelium. 
SARS-CoV-2 has been shown to infect cells expressing 
angiotensin-converting enzyme 2 (ACE2) receptors, 
which are abundant in the nasal cavity (de Melo et al., 
2021). Viral invasion of  nasal epithelial cells may lead to 
inflammation, neuronal injury, and disruption of  olfactory 
signalling pathways, resulting in anosmia. However, the 
exact pathophysiological mechanisms require further 
investigation.
In several aspects, Anosmia in COVID-19 appears to differ 
from anosmia caused by other viral infections. Unlike 
some viruses that directly damage neural epithelium, such 
as certain strains of  coronaviruses, COVID-19-induced 
anosmia is characterised by a relatively rapid onset and 
recovery (Glezer et al., 2021). Additionally, COVID-19 
patients frequently report anosmia without accompanying 
nasal congestion or obstruction, distinguishing it from 
other causes of  olfactory dysfunction.
Anosmia in COVID-19 patients has been associated 
with distinct clinical features and outcomes. Studies have 
indicated that COVID-19-induced anosmia tends to 
resolve spontaneously within a few weeks to months in 
most cases (Talavera et al., 2020). However, the duration 
of  anosmia can vary widely among individuals, with some 
patients experiencing persistent or recurrent symptoms. 
Despite its transient nature, anosmia can significantly 

impact quality of  life and may contribute to long-term 
sequelae in some cases.
Recognising anosmia as a prominent symptom of  
COVID-19 has important implications for disease 
management and control efforts. Anosmia should 
be considered in the clinical evaluation of  suspected 
COVID-19 cases, particularly in the absence of  other 
respiratory symptoms. Early detection of  anosmia can 
facilitate prompt isolation, testing, and contact tracing, 
helping to limit the spread of  the virus within communities 
(Shamsundara & Jayalakshmi, 2023). Moreover, including 
anosmia in COVID-19 screening protocols may improve 
the accuracy of  case identification and enhance the 
effectiveness of  public health interventions.

MATERIALS AND METHODS
Study Setting
This retrospective study was conducted at the Covid-19 
Command & Control Center (CCC) under the auspices 
of  the Dubai Health Authority (DHA) in Dubai, United 
Arab Emirates (UAE). The study period spanned from 
May to July 2020.

Sample Size and Data Source
The study included 1079 cases, and data were retrieved 
from patient records stored in the DHA’s digital files 
system, SALAMA: Electronic Files System.

Exclusion Criteria
Patients were excluded from the study if  they met any of  the 
following criteria: individuals below 18 years old or above 
60 years old, pregnant women, immunocompromised 
patients receiving immune suppressive medications, 
patients with physical disabilities, individuals managed by 
healthcare institutes other than the CCC, patients residing 
outside the emirate of  Dubai, and those with mental or 
psychological disorders. Patients already admitted to the 
hospital via the emergency department were also excluded.

Data Collection
A standardised investigation tool was utilised for data 
collection, encompassing various parameters such as 
age, smoking status, body mass index (BMI), presence 
of  comorbidities, symptoms, presence of  local nasal 
pathology, presence of  loss of  taste, onset of  loss of  
smell, and duration of  loss of  smell.

Study Execution
The study was conducted by DHA staff  members 
stationed at the DHA COVID-19 Command & 
Control Center in Dubai, UAE. Data collection was 
facilitated through telephonic encounters with the study 
participants. The study sample was randomly selected to 
ensure patient confidentiality, and no personal identifying 
information was included in the study dataset. Verbal 
consent was obtained from all participants before data 
collection, per ethical guidelines.



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Statistical Analysis
Data analysis was performed using appropriate statistical 
methods, including descriptive statistics, to summarise 
the demographic and clinical characteristics of  the study 
population. If  deemed appropriate, inferential statistics 
may be employed to assess associations between variables.

Ethical Considerations
All procedures were conducted according to ethical 
principles outlined in the Declaration of  Helsinki and 
other applicable guidelines. Patient confidentiality and 
privacy were strictly maintained throughout the study. 
Informed consent was obtained from participants.

RESULTS
All variables, including the percentage, correlation, 
coefficient of  determination, and p-value, were evaluated 
using SPSS after all data had been analysed using standard 
descriptive statistics. A total of  1079 patients—878 males 

(81.3%) and 201 females (18.7%)—were included in the 
study as positive cases.
The correlation coefficients observed in the analysis 
exhibit a negligible magnitude, with values approaching 
zero, indicating an absence of  substantial linear 
relationships between the variables under scrutiny. 
Concurrently, the determination coefficients, indicative 
of  the proportion of  variability in one variable that 
another can explain, approach insignificance. However, 
the confidence level exceeds 99%, underscoring a high 
degree of  reliability in the findings. Moreover, the 
p-values, which signify the probability of  obtaining 
results as extreme as those observed, are consistently 
greater than 0.05 across all analysed factors. These 
collective findings suggest that variables such as 
gender, smoking habits, diabetes, hypertension, lung 
disease, heart disease, thyroid disorders, malignancy, 
and pregnancy are associated with the loss of  olfactory 
function, as elucidated in Table 1.

Table 1: Correlation between loss of  smell and comorbidities
Frequency 
(Percent)

Frequency Loss 
of  Smell (Percent)

Correlation R Coefficient of  
Determination R 
Square

P value.

Gender Male 878 (81.4) 177 (20.2) X2 (3, N = 126) 
= 10.1, p = .017.

.015 .000
Female 201 (18.6) 67 (33.3)

Smoking NO 928 (86.0) 211 (22.7) .007 .000 .810
YES 151 (14.0) 33 (21.9)

Diabetes NO 1013 (93.9) 228 (22.5) .010a .000 .744
YES 66 (6.1) 16 (24.2)

Hypertension NO 986 (91.4) 223 (22.6) .000 .000 .994
YES 93 (8.6) 21 (22.6)

Lung Disease NO 1068 (99.0) 240 (22.5) .033 .001 .274
YES 11 (1.0) 4 (36.4)

Heart Disease NO 1067 (98.9) 242 (22.7) .015 .000 .621
YES 12 (1.1) 2 (16.7)

Thyroid 
Disease

NO 1058 (98.1) 240 (22.7) .012 .000 .694
YES 21 (1.9) 4 (19.9)

Malignancy NO 1075 (99.6) 241 (22.4) .076 .006 .012
YES 4 (.4) 3(75)

Pregnancy NO 1074 (99.5) 241 (22.4) .061 .004 .045
YES 5 (.5) 3 (60)

The observation regarding loss of  taste is noteworthy that 
a correlation coefficient of  0.584 and a determination 
coefficient of  0.341 were observed in the context of  
loss of  taste and loss of  smell, suggesting a potential 
association of  these symptoms with approximately 34.1% 
of  COVID-19 cases. Despite these coefficients indicating 
a moderate relationship, they denote a modest explanatory 

power regarding the variability observed. Furthermore, 
the confidence level exceeds 99%, indicating a high 
degree of  certainty in the observed results. Importantly, 
all p-values associated with the analysed variables are 
below 0.05, underscoring their statistical significance, as 
shown in Table 2.



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In examining age groups, no discernible discrepancies in 
percentages were observed. The correlation coefficient, 
approaching insignificance, and a determination 
coefficient close to zero suggest a negligible association 

between age and the incidence of  loss of  smell, with a 
confidence level exceeding 99% and a p-value of  0.924, 
as outlined in Table 3.
Nearly all patients who reported experiencing loss of  

Table 2: Correlation between loss of  smell and other COVID symptoms
Frequency 
(Percent)

Frequency Loss 
of  Smell (Percent)

Correlation R Coefficient of  
Determination R 
Square

P value.

Asymptomatic NO 598 (55.4) 198 (33.1) .280 .078 .000
YES 481 (44.6) 46 (9.6)

Loss of  Taste NO 831 (77.0) 77 (9.3) .584 .341 .000
YES 248 (23.0) 167 (67.3)

Sore Throat NO 937 (86.8) 185 (19.7) .176 .031 .000
YES 142 (13.2) 59 (41.5)

Fever NO 721 (66.8) 100 (13.9) .297 .088 .000
YES 358 (33.2) 144 (30.2)

Cough NO 790 (73.2) 138 (17.5) .203 .041 .000
YES 289 (26.8) 106 (36.7)

Difficult 
Breathing

NO 981 (90.9) 208 (21.2) .107 .011 .000
YES 98 (9.1) 36 (36.7

Diarrhea NO 990 (91.8) 204 (20.6) .160a .026 .000
YES 89 (8.2) 40 (45)

Table 3: Distribution of  patients according to age groups
Frequency 
(Percent)

Frequency Loss of  
Smell
(Percent)

Correlation R Coefficient of  
Determination 
R squire

P value 
Sig.

Age from 1 to 10 4 (.4) 0 (0) .003 .000 .924
from 11 to 20 21 (1.9) 5 (23.8)
from 21 to 30 337 (31.2) 78 (23.2)
from 31 to 40 441 (40.9) 97 (22)
from 41 to 50 192 (17.8) 45 (23.4)
from 51 to 60 72 (6.7) 17 (23.4)
more 60 12 (1.1) 2 (16.7)

smell subsequently recovered, constituting approximately 
95% of  cases. Additionally, it is observed that about 
47% of  patients identified loss of  smell as their initial 
symptom of  COVID-19, as depicted in Table 4.
Table 5 displays the distribution of  durations in days 

associated with loss of  smell among the study population. 
Varied durations are evident, with a majority experiencing 
symptoms for shorter periods. Notably, the highest 
frequency occurs within the seven-day range, constituting 
3.7% of  cases, as depicted in Table 5.

Table 4: loss of  smell and other parameters before swab, before other symptoms and outcomes
Loss of  Smell Frequency (Percent)

Swab Test Before 133 (54.5)
After 111 (45.5)

Other Symptoms NO 34 (14.3)
Before 114 (47.9)
After 90 (37.8)

The outcome of  Loss of  Smell Cured 233 (95.5)
Impaired 11 (4.5)



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DISCUSSION
The global spread of  COVID-19 has presented a spectrum 
of  manifestations ranging from mild flu-like symptoms to 
severe pneumonia. Notably, alterations in olfactory and 
gustatory senses have emerged as prominent indicators 
of  infection with the novel coronavirus. This assertion is 
substantiated by the prevalence of  anosmia and ageusia 
exceeding 22% among COVID-19 patients (Mastrangelo 
et al., 2021). However, while these sensory changes serve as 
crucial diagnostic markers, the precise onset and duration 
of  such symptoms remain to be definitively established. 
Comprehensive quantification of  loss of  smell and taste 
and a clear understanding of  their temporal relationship 
with COVID-19 holds significant promise in facilitating 
early diagnosis, thus mitigating further transmission and 
potential complications associated with the disease. In 
our study encompassing 1075 patients, males constituted 
the majority at 81.4%, with females comprising 18.6% of  
the cohort. The median age fell within the 31 to 40-year 
range. Notably, individuals experiencing loss of  smell 
tended to be younger than those without this symptom.
Furthermore, our findings indicate that 33.3% of  female 
and 20% of  male cases reported insomnia. Interestingly, 
nearly half  of  the patients (47.3%) noted the onset 
of  anosmia preceding other COVID-19 symptoms, 
while 14.3% experienced it concurrently with different 

manifestations, and 37.8% reported its occurrence after 
other symptoms. Additionally, a notable proportion 
(9.6%) of  individuals reported anosmia as their sole 
symptom associated with COVID-19. These findings 
collectively underscore the importance of  recognising 
and understanding the temporal dynamics of  olfactory 
and gustatory dysfunctions in COVID-19, thereby aiding 
in more effective disease management and control efforts.
In our investigation, we examined the correlation 
coefficients, determination coefficients (R square), and 
significance levels, alongside percentages, about several 
variables, including smoking, diabetes, hypertension, 
heart disease, lung disease, thyroid disease, malignancy, 
and anosmia among COVID-19 patients. Additionally, 
we explored the potential associations between other 
symptoms—sore throat, fever, cough, difficulty breathing, 
and diarrhoea—and anosmia. Despite the importance of  
comorbidities in predicting disease severity, our study did 
not reveal significant correlations between COVID-19 
and various factors, including age, gender, smoking, heart 
disease, diabetes, hypertension, lung disease, thyroid 
disease, and malignancy. Notably, while some associations 
were observed, such as between loss of  smell and taste, 
the overall correlations between anosmia and other 
symptoms were weak. For instance, the correlation and 
determination coefficients for sore throat, fever, cough, 
difficulty breathing, and diarrhoea were modest. These 
findings underscore the need for further research to 
comprehensively elucidate the relationship between 
anosmia and COVID-19 symptoms, especially regarding 
disease prognosis and management.
In our analysis of  the asymptomatic group, we observed 
that 33.1% of  patients exhibited anosmia, albeit with 
a coefficient factor of  0.280 and R square of  0.07, 
indicating that 7.8% of  asymptomatic individuals 
experienced this symptom, based on a robust sample 
size of  481 patients, which suggests that anosmia may 
be overlooked compared to more severe symptoms, 
such as breathing difficulty and fever, as patients and 
healthcare workers tend to prioritise these more acute 
manifestations. Regarding the duration of  anosmia, the 
median range spanned 3 to 10 days, with 95% of  patients 
(233 individuals) reporting recovery by the study’s 
conclusion. However, 5% of  patients (11 individuals) 
had yet to recover, warranting further investigation and 
follow-up. Importantly, we investigated whether anosmia 
preceded or followed other symptoms, finding that 47% 
of  cases occurred before other symptoms, 37% after, and 
14.3% concurrently. This distinction may aid healthcare 
workers in predicting diagnoses and curbing infection 
transmission.
Our study aligns with the study of  Hopkins et al. 
(2020), which comprised 2428 male and female adults, 
predominantly women (73%) and individuals under 40 
(64%) (Hopkins et al., 2020). The study, conducted in 
London, UK, reported varying onset times for anosmia, 
with 13% occurring before other symptoms, 38.4% 
simultaneously, and 48.6% after. Symptoms persisted for 

Table 5: Loss of  smell and duration
Days Frequency (Percent)
1.00 3 (.3)
2.00 15 (1.4)
3.00 30 (2.8)
4.00 27 (2.5)
5.00 37 (3.4)
6.00 8 (.7)
7.00 40 (3.7)
8.00 11 (1.0)
9.00 4 (.4)
10.00 21 (1).9
11.00 1 (.1)
12.00 5 (.5)
13.00 1 (.1)
14.00 15 (1.4)
15.00 4 (.4)
16.00 1 (.1)
17.00 1 (.1)
20.00 5 (.5)
21.00 1 (.1)
25.00 1 (.1)
30.00 4 (.4)
49.00 1 (.1)
60.00 2 (.2)



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1 to 4 weeks, showing significant improvement within 
the initial 2 weeks. A majority (74.4%) experienced a 
complete loss of  smell, while 17.3% reported severe loss. 
Notably, 90% noted a reduction in taste, but 61% could 
still discern basic flavours. Additionally, 17% said no other 
COVID-19 symptoms, while cough or fever was prevalent 
in 51% of  cases with additional symptoms. In our study 
of  1075 patients, with a male predominance (81.4%), the 
median age ranged from 31 to 40 years. Anosmia was more 
common in younger patients, and insomnia was noted in 
33.3% of  females and 20% of  males. Similarly, anosmia 
onset varied, with 47.3% preceding other symptoms, 14.3% 
concurrent, and 37.8% subsequent, with 9.6% reporting 
no other associated symptoms.
Comparing our study with Spinato et al. (2020), which 
included 202 male and female adults with an average age 
of  56 years in Italy, notable similarities and differences 
emerge (Spinato et al., 2020). In both studies, anosmia 
or loss of  taste exhibited varied onset times relative 
to other symptoms, with comparable proportions 
reported before, during, and after other manifestations. 
Specifically, 11.9% experienced symptoms before, 22.8% 
concurrently, and 26.7% afterwards, with 3.0% presenting 
with anosmia or loss of  taste as the sole symptom. In 
our study of  1075 patients, predominantly male (81.4%), 
similar patterns were observed, with 47.3% experiencing 
anosmia before other symptoms, 14.3% concurrently, 
and 37.8% afterwards, with 9.6% reporting no other 
associated symptoms. Notably, our findings diverge in the 
presence of  nasal obstruction, as reported by 34.6% of  
individuals with altered sense of  smell or taste in Spinato 
et al. In contrast, our study did not find a correlation with 
insomnia. Furthermore, our study encompassed a larger 
sample size and investigated the impact of  comorbidities, 
which needed to be explored in previous research.
Compared to Lechien et al. (2020)a, which involved 1420 
individuals aged over 15 years, male and female, our study 
presents notable similarities and distinctions (Lechien, 
Chiesa-Estomba, Place, et al., 2020). While our research 
focused on a specific demographic, encompassing 1075 
patients, predominantly males (81.4%), Lechien et al. 
(2020) examined a larger cohort with a more balanced 
gender distribution (458 men and 962 women) and a 
slightly older average age of  39.17 years. Furthermore, 
their multicenter European study, conducted across 
various regions, including France, Italy, Spain, Belgium, 
and Switzerland, provided a broader geographical 
perspective compared to our single-centre investigation. 
Interestingly, both studies highlighted the prolonged 
duration of  symptoms among COVID-19 patients, with 
Lechien et al. reporting an average duration of  11.5 ± 
5.7 days for mild to moderate cases and noting that loss 
of  smell persisted for at least 7 days post-recovery in 
37.5% of  patients, mirroring findings in our study. These 
similarities underscore the consistency of  observations 
regarding the persistence of  anosmia in COVID-19 
patients across different populations and settings 
(Lechien, Chiesa-Estomba, Place, et al., 2020).

The prevalence of  loss of  smell appeared higher among 
women, with younger patients exhibiting a greater 
propensity for this symptom, as observed in our study of  
1075 patients in Dubai compared to a multicenter study 
in Europe by Lechien et al. (2020)b, while our research 
indicated that 70.2% of  individuals experience loss of  
smell and 54.2% experience loss of  taste, the European 
research reported different percentages. In our cohort, 
comprising 81.4% males and 18.6% females with a median 
age of  31 to 40, anosmia was more common among 
younger patients. Notably, 47.3% of  our patients reported 
anosmia preceding other symptoms, 14.3% occurring 
concurrently, and 37.8% following, with 9.6% reporting 
no other associated symptoms. Although similarities were 
noted in age group findings, discrepancies emerged in 
the total percentage of  individuals experiencing loss of  
smell, highlighting potential variations across different 
populations and settings (Lechien, Chiesa-Estomba, De 
Siati, et al., 2020).
Comparing our study with Kaye et al. (2020), which 
comprised 237 adults with an average age of  39.6 years from 
various countries, including the United States, Mexico, Italy, 
and the United Kingdom, notable parallels and differences 
emerge. While both studies observed the onset of  anosmia 
relative to COVID-19 diagnosis, with 73% experiencing 
anosmia before diagnosis in Kaye et al. and 47.3% reporting 
pre-diagnosis anosmia in our study, variations are evident 
in the timing of  symptom improvement. Kaye et al. (2020) 
reported an average improvement time of  7.2 ± 3.2 days 
post-diagnosis, while our study did not provide specific data 
on symptom resolution. These findings highlight consistent 
trends in the onset of  anosmia about COVID-19 diagnosis 
across different populations while emphasising potential 
differences in the duration of  symptom resolution (Kaye 
et al., 2020).

CONCLUSION
This study concludes that 22% of  COVID-19 patients 
experience anosmia, or loss of  smell, as the initial 
symptom. This symptom is transient and is not 
significantly correlated with comorbidities such as 
diabetes, hypertension, heart disease, lung disease, and 
thyroid disease. However, there is no correlation between 
anosmia and other common COVID-19 symptoms 
like fever, cough, shortness of  breath, and diarrhoea. 
The study provides valuable insights into the temporal 
patterns of  anosmia onset and resolution among 
COVID-19 patients and its association with other clinical 
features. Despite the absence of  strong correlations 
with comorbidities or other symptoms, anosmia remains 
a significant early indicator of  COVID-19 infection, 
underscoring its importance in the diagnostic process. 
Healthcare professionals can improve the identification 
and management of  COVID-19 cases by recognising 
anosmia as a distinct clinical feature. Further research 
is needed to elucidate the underlying mechanisms of  
anosmia in COVID-19 and its implications for disease 
prognosis and management.



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