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Why COVID-19 Long Haulers?
By Jorge Garza-Ulloa, Research Consultant Services (www.garzaulloa.org)
Figure 1 Long Haulers are the patients that they had COVID-19 and they have tested negative, but continue with many post-
COVID 19 symptoms
Abstract
Today is know that during and after infection with the Coronavirus SARS-CoV-2 better
known as COVID-19 all infected persons may suffer severe physical and mental
affectation presenting a big variety of neurological symptoms and others [1]. They are
caused by the infection mainly from “severe damages by inflammation at the different
organs of human body into the complex network of all symbiotic systems”. Many of the
symptoms has been documented for many patients with mild to moderate COVID-19,
and they can last weeks to months, and may be years with their virus symptoms. These
patients are known as “long haulers based in the facts that they had COVID-19 and they
have tested negative but still continue with many symptoms”. Where “some people have
reported feeling better for days or even weeks then relapsing… meanwhile, others
report they are just not feeling like themselves”. In this research the goal is demonstrate
how COVID-19 affect all symbiotic systems based on their normal interrelation
functions.
COVID-19 “long haulers” symptoms
The most common symptoms reported for COVID-19 “long haulers” are:
• Cough, difficulty breathing or shortness of breath.
• Fatigue sometimes debilitating, experience fatigue that comes and goes.
• Body aches, joint pain, or muscle pain.
• Loss of taste and smell — even if this did not occur during the height of illness. A
continued loss of taste and smell post-infection has also caused distress for many
in their daily life.
• Headaches, difficulty sleeping.
• Gastrointestinal issues such as diarrheas.
• Heart problems such as palpitations, besides persistent pain, or pressure in the
chest.
• Dizziness on standing.
• Depression or anxiety.
• Inability of exercise.
• Skin rashes.
And many more
Some report even suicides due to severe and continuous post-COVID symptoms, the
most frequently emerging as sequela of COVID-19 infections are “tinnitus and cognitive
decline issues”. Where:
• “Tinnitus” is a loud buzzing or ringing in the ears that can cause a detrimental
impact on one’s quality of life [2] Around 40% of people who had Covid-19 found
that they were already existing “tinnitus symptoms worsened”, while others
reported they “acquired tinnitus immediately after a Covid-19 infection”.
“Tinnitus” causes an increase in comorbid anxiety and depression. Out of people
with tinnitus, 33% have major depression, and 45% have anxiety. And it is
possibly causal relationship between “tinnitus and an increased rate of suicide”
[3].
• “Cognitive decline issues” known as “brain fog” is used to describe how post
COVID-19 infected people feel when their thinking is sluggish, fuzzy, and not
sharp. Some have it so intense that they are no longer even able to work. But it is
important to mention that some possible causes also could be also: poor sleep
quality, feelings of loneliness, depression, increased stress or anxiety, dietary
changes, decreased physical activity or side effects of certain medications [4].
“COVID-19 long haulers symptoms” are hard to identify and understand why something
wrong is occurring since the short time the disease was discovered and understand why
“their symptoms get worse after physical or mental activities causing significant
impairment in their quality of life”. At the beginning of 2021, the health system officially
decides to understand the why and learn how to detect and treat "COVID -19 long
haulers", but they still require more time for clinical trials results that will allows analyze
and understand their complexity.
What cause post-COVID syndrome?
The probably main explicable reason for “long haulers” (post-COVID symptoms) is in
the human body complex network of symbiotic systems interdependency alteration in
“respiratory system”, “cardiovascular or circulatory system”, “nervous system”,
“immune system”, “digestive system”, “excretory system”, “reproductive system”,
“muscular system”, “lymphatic system”, “endocrine system”, and “integumentary
system” . They are interconnected systems that stabilized the human body but seems that
in the “COVID-19 long haulers” their normal functions systems are altered even without
the actual presence of the virus, presenting many of the post-COVID symptoms by an
extended period. Where the main functions and affectation of each symbiotic system are
summarized at table I, these are:
Table 1 Long Haulers and their frequently symptoms reported at the symbiotic systems.
Respiratory system
o “Respiratory system” is affected by COVID-19 mainly by infection in the lungs, that
carry out the exchanges of gases as we breathe, altering the amount of red blood cells
that collect the oxygen from the lungs and carry it to the different parts of the body
where is needed and collect the carbon dioxide that transport back to the lungs to be
expelled from the body. This decreases the oxygen needed in the human body known
as “hypoxia”, condition that affect the brain cells and initiate the process of brain
damage and finally neurons death. When the virus gets in your body, it meets the
mucous membranes that line your nose, mouth, and eyes [0]. The virus enters a
healthy cell and uses the cell to make new virus parts. It multiplies, and the new
viruses infect nearby cells [5][6]. The COVID-19 was first cataloged as a disease
caused by SARS-CoV-2 that can trigger a respiratory tract infection. It can affect your
upper respiratory tract (sinuses, nose, and throat) or lower respiratory tract
(windpipe and lungs). As COVID-19 pneumonia progresses, more of the air sacs
become filled with fluid leaking from the tiny blood vessels in the lungs. Eventually,
shortness of breath sets in, and can lead to acute respiratory distress syndrome
(ARDS), a form of lung failure [7]. For “COVID Long haulers is frequently the
inflammation at lower and upper tracts for shortness of breath” as summarized in
table 1.
Cardiovascular or circulatory system”
o “Cardiovascular or circulatory system” is affected mainly by inflammation in the
heart, veins, arteries capillaries, etc. The heart and blood vessel work together to
circulate the blood throughout the body to provide oxygen and nutrients as amino
acids, electrolytes, carbon dioxide, hormones etc. this helps to fight diseases, stabilize
temperature, acidity, or alkalinity (pH), and maintain ‘homeostasis” as the process to
maintains a relatively stable equilibrium between interdependent elements, especially
as maintained by physiological processes [0]. SARS-CoV-2 has been demonstrated to
interact with “ACE2 (Angiotensin-converting enzyme 2)”, that is an enzyme attached
to the membrane of cells located in the intestines, kidney, testis, gallbladder, and
heart, and enter the host’s cells, particularly cardiac myocytes, and alveolar epithelial
cells [8] [9]. The binding of SARS-CoV-2 to “ACE2” causes acute myocardial and lung
injury through the alternation in “ACE2” signaling pathways [10]. Considerable
attention is needed for viral infection related heart damage at the time of treatment.
The cardiologist community must play an essential role in managing and treating
patients affected by this disease [11]. For “COVID Long haulers is frequently the
inflammation in the heart (causes acute myocardial), veins, arteries capillaries” as
summarized in the table 1.
Nervous system
o “Nervous system” is affected by COVID-19 virus in the brain, and extents the
inflammation also to the spinal cord, nerve cells and all nerves that connect these
organs with the rest of the human body. The brain and the spinal cord form the “CNS
central nervous system”, where the information is evaluated, and decision are made
and send them to the “sensory nerves” or by vice versa in the “sensory organs”
information are send to them [0]. The different nerves affected that carry signals
to/from muscles, glands, and organs are responsible for regulate their normal
functions and cannot achieve the equilibrium between interdependent elements in
the human body and the disease [11]. Describing the different neurological conditions
that may occur in COVID-19 patients and how to diagnose them, as well as likely
pathogenic mechanisms. This is key to direct appropriate clinical management and
treatment [12]. For “COVID Long haulers is frequently on patients that have
neurological manifestations of COVID-19, as headache, dizziness, decreased
alertness, difficulty concentrating, confusion, disorders of smell and taste, seizures,
strokes, weakness, muscle pain, and disabling strokes”, as summarized in table 1.
Immune system
o “Immune system” accomplishes its responsibility for the body´s defense against
infectious organisms and other invaders. allowing the attack of organisms and
substances that invade body systems and cause disease. After people recover from
infection with a virus, the “immune system” retains a memory of it. Normally the
immune cells and proteins that circulate in the body can recognize and kill the
pathogen if it is encountered again, protecting against disease, and reducing illness
severity. This long-term immune protection involves several components.
Antibodies—proteins that circulate in the blood—recognize foreign substances like
viruses and neutralize them. Different types of “T cells” that help recognize and kill
pathogens. “B cells” make new antibodies when the body needs them. All these
immune-system components have been found in people who recover from SARS-
CoV-2, the virus that causes COVID-19. But the details of this immune response and
how long it lasts after infection have been unclear. Scattered reports of reinfection
with SARS-CoV-2 have raised concerns that the immune response to the virus might
not be durable [13]. The initial decisions of the innate immune system are responsible
for a proper or improper response of the adaptive immune system and, along with
comorbidities, are directly associated with disease progression [14]. “In COVID-19
long haulers virus altered the behavior of molecular and cellular components of the
immune system, but more details are necessary to research to understand how and
why” [15], as summarized in table 1.
Digestive system
o “Digestive system” as a group of organs working together to convert food into energy
and basic nutrients to feed the entire body. The alimentary canal is made up of the
oral cavity, pharynx, esophagus, stomach, small intestine, large intestines an anus.
Accessory organs of the digestive system include: the teeth, tongue, salivary glands,
liver, gallbladder, and pancreas [0]. In some instances, digestive symptoms are
reported as the initial presentation of COVID-19 [16]. These findings suggest that the
virus can impair the digestive system and may explain the range of digestive
symptoms seen in COVID-19 [17]. Digestive symptoms should be treated with caution
in the early stage of COVID-19, and dynamic monitoring of liver function and
cytokines is imperative during clinical practice to reduce the complications and
mortality of COVID-19 [18]. The most common symptoms are “anorexia and
diarrhea”. In about half of the cases, viral RNA could be detected in the stool, which is
another line of transmission and diagnosis. COVID-19 has a worse prognosis in
patients with comorbidities, although there is not enough evidence in case of previous
digestive diseases [19]. Compared with patients without gastrointestinal sequelae at
90 days, patients with gastrointestinal sequelae more frequently presented with
“dyspnea (difficult breathing)” (23% vs 12%) and “myalgia (
Muscle pain)
” (17% vs
11%) on admission, although these differences were not significant. Patients with
gastrointestinal sequelae were less frequently severely ill than were those without
gastrointestinal sequelae (17% vs 37%; p=0·021), although after adjustment for
confounding factors, this difference was not significant (p=0·051). Patients with
gastrointestinal sequelae at 90 days exhibited a lower frequency of supplemental
oxygen therapy (79% vs 94%; p=0·016), and a trend of lower frequency of intensive
care unit admission during hospitalization. Patients with gastrointestinal sequelae at
90 days were treated more often with proton pump inhibitors (PPIs) and
corticosteroids and were less frequently treated with enteral nutrition than were
patients without such sequelae. “In COVID-19 long haulers reports: diarrhea,
nausea, vomiting, and diminished appetite even after 90 days” [20], as summarized
in table 1.
Excretory system
o “Excretory system” includes the renal system that consists of kidneys, ureters,
bladder, and the urethra. The purpose of the renal system is to eliminate wastes from
the body, regulate blood and blood pressure, control levels of electrolytes e.g.,
sodium, potassium and calcium, and metabolites, and regulate blood pH (specify the
acidity or alkalinity). Urine is formed in the kidneys through a filtration of blood. The
kidneys have an extensive blood supply via the renal arteries which leave the kidneys
via the renal vein [0]. Some people suffering with severe cases of COVID-19 are
showing signs of kidney damage, even those who had no underlying kidney problems
before they were infected with the coronavirus. Signs of kidney problems in patients
with COVID-19 include high levels of protein in the urine and abnormal blood work.
The kidney damage is, in some cases severe enough to require dialysis. Besides “many
patients with severe COVID-19 are those with co-existing, chronic conditions,
including high blood pressure and diabetes, both increase the risk of kidney
disease”. The impact of COVID-19 on the kidneys is not yet clear. Here are some
possibilities doctors and researchers are exploring as:
▪ The virus itself infects the cells of the kidney.
▪ Kidney cells have receptors that enable the new coronavirus to attach to them,
invade, and make copies of itself, potentially damaging those tissues.
▪ Another possibility is that kidney problems in patients with the coronavirus
are due to abnormally low levels of oxygen in the blood, Cytokine storms
organized by the immune system can destroy kidney tissue by inflammation.
[21].
▪ Urinary concentrations of chromium, manganese, copper, selenium, cadmium,
mercury, and lead after creatinine adjustment were found to be higher in
severe patients than the non-severe cases with COVID-19. And among the
severe cases, these elements were also higher in the deceased group than the
recovered group. When the weeks of the post-symptom onset were taken in
account, the changes of these urinary elements were existed across the clinical
course since the disease onset [22].
Acute kidney injury occurs in up to 57% of COVID-19 hospitalizations and 78% of
intensive care unit admissions in patients with COVID-19, noted the authors. In
addition, reports from early in the pandemic indicate that a little more than a
third of patients with COVID-19 who survived had not yet recovered baseline
kidney function at a median of 21 days after leaving the hospital [23]. “COVID-19
long haulers reports that individuals recovering from acute kidney injury, will
require kidney monitoring after they leave the hospital a median of 21 days”, as
summarized in table 1.
Reproductive system
o “Reproductive system” is a system of sex organs within an organism which work
together for the purpose of sexual reproduction. Many substances such as fluids,
hormones and phenomes are also important accessories to the reproductive system.
The combination of genetic material between two individual of different sex allows
the possibility of greater genetic fitness of the young born of living organisms. SARS-
CoV-2 has been demonstrated to interact with “ACE2”, where “ACE2 receptors” are
much more abundant in the male reproductive system than the female reproductive
system. Low expression of “ACE2” was demonstrated in the fallopian tube (ciliated
and endothelial cells), ovary, vagina, cervix and endometrium. On the other hand,
“ACE2” expression in the testis is among the highest observed, with high expression
in Leydig and Sertoli cells and medium expression in glandular cells of the seminal
vesicle. As a result, it is expected that the testes will be more vulnerable than the
ovaries to the detrimental effects of a SARS-CoV-2 infection [24]. In females, a severe
acute illness may alter the hypothalamic-pituitary gonadal (HPG) axis function,
decreasing the endogenous production of Estrogens and Progesterone [25]. “Scientific
findings related to the impact of the COVID-19 pandemic on the reproductive
process, considering gender, hormonal balance, gonad functions, pregnancy, and
ART, the sociosexual dimension of COVID-19 disease and precautions that should be
taken to avoid infection via sexual transmission or vertical transmission, which
may alleviate the fear associated with continuing normal social relationships and
economic activities [26]. Besides, COVID-19 long haulers report a high frequency of
maternal mental health problems, such as clinically relevant anxiety and
depression, but these are consequences of social- economic problems affected by the
pandemic as fear of putting your own and your child’s health at risk to go to a clinic
or medical facility comes into play, increased childcare demands and other factors”,
as summarized in table 1.
Muscular System
o “Muscular System” permits movement of the body, maintains posture, and circulate
blood throughout the body. The muscular system allows for movements by
contracting, it consists of skeletal, smooth, and cardiac muscles. The muscle system in
vertebrates is controlled through the nervous systems, although some muscles like
the cardiac muscle can be completely autonomous. Smooth muscles are controlled
directly for the autonomic nervous system and are involuntary, meaning that they
incapable of being move by conscious thought, for example the heart muscles [0].
COVID-19 infect the respiratory system, and there are direct and indirect effects of
this infection on multiple organ systems, including the musculoskeletal system.
Epidemiological data from the SARS pandemic of 2002 to 2004 identified myalgias,
muscle dysfunction, osteoporosis, and osteonecrosis as common sequelae in patients
with moderate and severe forms of this disease. Early studies have indicated that
there is also considerable musculoskeletal dysfunction in some patients with COVID-
19[27]. “COVID-19 long haulers report frequently musculoskeletal as fatigue,
myalgia (pain feels like a pulled muscle), and arthralgia (pain in joints)” [28], as
summarized in table 1.
Lymphatic system
o “Lymphatic system” is a network of tissues and organs that help rid the body of
toxins, waste, and other unwanted materials. The primary function of the lymphatic
systems is to transport lymph, as a fluid containing infection –fighting white blood
cells, throughout the body. The lymphatic system primary consists of vessels, which
are like the circulatory system veins and capillaries. The vessels are connected to
lymph nodes, where the lymph is filtered. The immune system does not develop in
anatomical isolation. Its development is inherently linked to that of the lymphatic
system. Furthermore, its function is synergistically linked to lymphatic activity. With
on-going research, we are now slowly appreciating how important the lymphatic
system is for generating and sustaining immune responses [0]. All COVID-19 vaccines
in current use deliver their payload into muscles. The Pfizer-Bio-nTech and Moderna
vaccines both use lipid nanoparticles (LNP) as mRNA carriers, while the Oxford
Astra-Zeneca and Sputnik vaccines use adenovirus vectors. mRNA and viral vaccines
must transfect cells to produce their corresponding proteins, whilst other vaccines,
such as the Chinese Sinovac vaccine, deliver inactivated virus proteins directly into
muscle. Whichever delivery system is used, viral proteins do not initiate immune
memory responses in muscles. They must be transported to lymph nodes to initiate a
response. This transport occurs primarily within antigen-presenting cells (APC),
specifically dendritic cells (DC), which are drawn from blood into the vaccination site
by local inflammation. Within tissues they are activated and endocytose and process
viral proteins, expressing them in the context of surface major histocompatibility
complex (MHC) molecules. The critical next step is entry into tissue-draining afferent
lymphatics; this process is actively facilitated by expression of lymphatic-homing
molecules on activated DC. “Some antigen may also travel directly to draining
lymph nodes. Even though this occurs by passive convection, it still relies on the
presence of intact functioning lymphatics. Only once delivered to local lymph nodes
can the antigen trigger a specific adaptive memory response from naïve B- and T-
cells located there. So, what then happens to those patients without a healthy,
functioning lymphatic system? [28]. COVID-19 long haulers report serious issues
like swollen lymph nodes, crisis-level hypertension, irregular thyroid hormones,
and anemia”, as summarized in table 1.
Endocrine system
o “Endocrine system” is the collection of glands of an organism that secrete hormones
directly in the circulatory system to be carried towards distant target organs. The
major endocrine glands include pineal gland, adrenal, pituitary gland, pancreas,
ovaries, testes, thyroid gland, hypothalamus, and adrenal glands. In addition to the
specialized endocrine organs, many other organs that are part of other body systems,
such as bone, kidney, liver, heart, and reproductive glands, have secondary endocrine
functions [0]. Several glands that signal each other in sequence are usually referred
to as an axis, for example, the hypothalamic-pituitary-adrenal axis. There is a
interactions between [29]:
▪ “COVID-19 and endocrine pancreas” affecting more to patients with pre-
existing type 2 diabetes mellitus (T2DM), Obesity has also been found to be
associated with severe disease in COVID-19. Adipose tissue express ACE2;
with higher adipose tissue, more would be the overall ACE2 expression that
would act as receptors for SARS-CoV-2
▪ “COVID-19 and adrenal gland” based on the primary immune invasive
strategy utilized by the SARS-CoV, like the influenza virus, is to knock down
the host’s cortisol stress response. A remarkably interesting hypothesis that
had been proposed is the expression of certain amino acid sequences by the
SARS-CoV that are molecular mimics of the host adrenocorticotropic hormone
(ACTH).
▪ “COVID-19 and the hypothalamus–pituitary” based in neurological
manifestations do occur in patients with COVID-19 and include, among others,
hyposmia. Expression of ACE2 by the olfactory epithelial supporting cells
could explain much of these olfactory symptoms. The portal of entry of the
virus into the central nervous system (CNS) remains uncertain and could be
via hematogenous route or directly thorough the cribriform plate.
Hypothalamic and pituitary tissues do express ACE2 and can theoretically be
the viral targets. In fact, on autopsy studies, edema, and neuronal
degeneration along with identification of SARS genome have been shown in
the hypothalamus. Biochemical evidence of hypothalamus-pituitary
involvement in SARS
▪ “COVID-19 and thyroid” autopsy study has shown marked destruction of the
follicular and parafollicular cells of thyroid. Destruction of follicular cells
would manifest as low T3 and T4; parafollicular cell damage would
theoretically lead to low levels of serum calcitonin.
“Endocrine manifestations in the post-acute COVID-19 setting may be
consequences of direct viral injury, immunological and inflammatory damage,
as well as iatrogenic complications” [30], as summarized in table 1.
Integumentary system
o “Integumentary system” that protects the body from various kind of damage, such as
loss of water or abrasion as a wound caused by superficial damage to the skin, no
deeper than the epidermis. The system compromises the skin including epidermis,
and dermis including sweat gland, sebaceous gland (oil), hair follicle, blood vessels,
nerves, nails, etc.; this system has a variety of functions as: waterproof, cushion, and
protect the deeper tissues, excrete wastes and regulate temperature, and is the
attachment site for sensory receptors to detect pain, sensation, pressure, and
temperature, besides with significant exposure to sunlight, the integumentary system
also provides for vitamin D Synthesis [0]. The tropism of the virus for the “structures
of the bronchial mucosa and the immune system cells” with a typical histopathologic
pattern has been demonstrated by using autopsy specimens from the lung, heart,
kidney, spleen, bone marrow, liver, pancreas, stomach, intestine, thyroid, and skin
[31]. “COVID long-hauler symptoms report persistent skin rashes manifestations, as
urticarial and morbilliform eruptions were relatively ephemeral, whereas
papulosquamous eruptions, and particularly pernio, were longer-lasting” [32], as
summarized in table 1.
Conclusion
It is time to act the post-COVID symptoms in “long haulers”. That report the following
50 more frequently symptoms based on a survey of a 1,567 “Long Haulers” at the Indiana
University Scholl of medicine at year 2020 are [34]:
• First ten more frequently Long Haulers symptoms are: 1) Fatigue, 2) Muscle or
body aches, 3) Shortness of breath or difficult breathing, 4) Difficult concentrating
or focusing, 5) Inability to exercise or be active, 6) Headache, 7) Difficulty
sleeping, 8) Anxiety, 9) Memory problems, and 10) Dizziness.
• Second ten more frequently Long Haulers symptoms are: 11) Persistence chest
pain or pressure, 12) Cough, 13) Joint Pain, 14) Heart Palpitations, 15) Diarrhea,
16) Sore Throat, 17) Night sweats, 18) Lost of smell (partial or complete), 19)
Tachycardia, and 20) Fever or Chills.
• Third ten more frequently Long Haulers symptoms are: 21) Hair loss, 22) Blurry
vision, 23) Congested or runny nose, 24) Sadness, 25) Neuropathy (feet or hands),
26) Reflux or heartburn, 27) Changing symptoms, 28) Lost of taste (partial or
full), 29) Phlegm (mucus membrane) in throat, and 30) Abdominal pain.
• Fourth ten more frequently Long Haulers symptoms are: 31) Lower back pain, 32)
Shortness of breath from bending over, 33) Nausea or vomiting, 34) Weight gain,
35) Clogged ears, 36) Dry eyes, 37) Calf cramps, 38) Tremors or shakiness, 39)
Sleeping more than normal, and 40) Upper back pain.
• Fifth ten more frequently Long Haulers symptoms are: 41) Eye floaters or flashing
of lights, 42) Rash, 43) Constant thirst, 44) Nerve sensations, 45) Tinnitus, 46)
Change sense of taste, 47) Sharp or sudden chest pain 49) Confusion, 49) Muscle
twitching, and 50) Feeling irritable.
A fortunately at least a handful of health systems in the U.S. and in the world that has
been initialize clinics trials and COVID-10 recovery programs to take cares of these
patients [33], to diminish and control the post-COVID-19 symptoms legacy. “COVID-19
Long haulers analysis musts be studied as a multidiscipline specialized interaction
between all of them based in the information between all different human body complex
network of symbiotic systems interdependency to answer the question: Why COVID-19
Long Haulers?”
Recommendations
In the meantime, the best way to prevent illness is to be vaccinated and avoid
unnecessary exposition to this virus and its new variants, avoiding the most common
modes of COVID-19 transmission: via respiratory droplets and Mini-Droplets, direct or
indirect contact and others.
• COVID-19 (SARS-CoV-2) is transmitted also very efficiently “via respiratory
droplets and Mini-Droplets”. Naturally produced droplets from humans:
“breathing”, “talking”, “sneezing”, “coughing”, etc. Where the: “Droplets” are
greater than 5 μm in diameter that fall rapidly around 3 feet, and “Mini-Droplets”
less than 5 μm in diameter that stay longer on the air falling around beyond 3 feet,
as shown in the following simulation where one infected person just breathing can
expanded the virus in a room.
Please see this video that analyze how the COVID-19 spread by air with only 1
person infected in the center of the room of 2 x 2 mts., as shown applying Artificial
Intelligence simulation Deep Learning algorithm [35]
https://youtu.be/3OPKtTyrt4g
• COVID-19 (SARS-CoV-2) is transmitted very efficiently via “direct or indirect
contact” of an infected human with other humans during their dairy routines.
• And others
References:
[0] Jorge Garza-Ulloa, Chapter 2 - Introduction to human neuromusculoskeletal systems,Applied
Biomechatronics using Mathematical Models, Academic Press,2018,Pages 53-118, ISBN
9780128125946, https://doi.org/10.1016/B978-0-12-812594-6.00002-0.
[1] Priya Sharma, Sumit Bharti, Isha Garg,Post COVID fatigue: Can we really ignore it?,
Indian Journal of Tuberculosis, 2021,ISSN 0019-5707
[2] https://www.cohenmedical.com/tinnitus-post-covid-new-long-haul-symptom/,
07/05/2021
[3] https://www.forbes.com/sites/ninashapiro/2021/03/21/texas-roadhouse-ceo-suicide-
post-covid-19-tinnitus-contributed/?sh=29783d252940., 07/05/2021
[4] Peter Novak,Post COVID-19 syndrome associated with orthostatic cerebral
hypoperfusion syndrome, small fiber neuropathy and benefit of immunotherapy: a
case report, eNeurologicalSci,Volume 21,2020,100276,ISSN 2405-6502,
https://doi.org/10.1016/j.ensci.2020.100276
[5] https://www.webmd.com/lung/what-does-covid-do-to-your-lungs, 07/05/2021
[6] Charles PAVIA, Maria Plummer, The evolution of rapid antigen detection systems
and their application for COVID-19 and other serious respiratory infectious diseases,
Journal of Microbiology, Immunology and Infection, 2021,ISSN 1684-
1182,https://doi.org/10.1016/j.jmii.2021.06.003
[7] https://www.hopkinsmedicine.org/health/conditions-and-
diseases/coronavirus/what-coronavirus-does-to-the-lungs, 07/05/2021
[8] Cascella M, Rajnik M, Cuomo A, Dulebohn SC, Napoli RD. Features, evaluation,
and treatment coronavirus (COVID-19), in StatPearls [internet]. Treasure Island:
StatPearls; 2020. https://www.ncbi.nlm.nih.gov/books/NBK554776/. Accessed 10
Aug 2020.
[9] Alan D. Kaye, Allyson L. Spence, Mariah Mayerle, Nitish Sardana, Claire M. Clay,
Matthew R. Eng, Markus M. Luedi, Michelle A. Carroll Turpin, Richard D. Urman,
Elyse M. Cornett, Impact of COVID-19 infection on the cardiovascular system: An
evidence-based analysis of risk factors and outcomes, Best Practice & Research
Clinical Anaesthesiology,2021,ISSN 1521-6896,
https://doi.org/10.1016/j.bpa.2021.02.003.]
[10] i W, Moore MJ, Vasilieva N, Sui J, Wong SK, et al. Angiotensin-converting
enzyme 2 is a functional receptor for the SARS coronavirus. Nature. 2003;426:450–
454. [PMC free article] [PubMed], 0705/2021
[11] R. S. Soumya, T. Govindan Unni, and K. G. Raghu, Impact of COVID-19 on the
Cardiovascular System: A Review of Available Reports, Cardiovasc Drugs Ther. 2020
Sep 14 : 1–15. doi: 10.1007/s10557-020-07073-y , 07/05/2021
[12] Igor. J Koralnik, Kenneth L. Tyler. COVID ‐19: a global threat to the nervous
system. Annals of Neurology, 2020; DOI: 10.1002/ana.25807][ Costantino Iadecola,
Josef Anrather, Hooman Kamel,Effects of COVID-19 on the Nervous System,
Cell,Volume 183, Issue 1,2020, Pages 16-27.e1, ISSN 0092-
8674,https://doi.org/10.1016/j.cell.2020.08.028.
[13] Dan JM, Mateus J, Kato Y, Hastie KM, Yu ED, Faliti CE, Grifoni A, Ramirez SI,
Haupt S, Frazier A, Nakao C, Rayaprolu V, Rawlings SA, Peters B, Krammer F, Simon
V, Saphire EO, Smith DM, Weiskopf D, Sette A, Crotty S., Immunological memory to
SARS-CoV-2 assessed for up to 8 months after infection. Science. 2021 Jan
6:eabf4063. doi: 10.1126/science.abf4063. Online ahead of print. PMID: 33408181
[14] J. Monserrat Sanz, A.M. Gómez Lahoz, R. Oliva Martín, Role of the immune
system in SARS-CoV-2 infection: immunopathology of COVID-19, Medicine -
Programa de Formación Médica Continuada Acreditado, Volume 13, Issue 33, 2021,
Pages 1917-1931, ISSN 0304-5412, https://doi.org/10.1016/j.med.2021.05.005
[15] https://medicine.yale.edu/news-article/understanding-immune-system-
blunders-in-response-to-the-coronavirus/, 07/6/2021
[16] Song Y, Liu P, Shi XL, et al. SARS-CoV-2 induced diarrhoea as onset symptom in
patient with COVID-19. Gut. Published online March 5, 2020
(https://doi.org/10.1136/gutjnl-2020-320891).
[17] Han C, Duan C, Zhang S, et al. Digestive symptoms in COVID-19 patients with
mild disease severity: Clinical presentation, stool viral RNA testing, and outcomes.
Am J Gastroenterol. Posted online March, 2020
[https://journals.lww.com/ajg/Documents/COVID19_Han_et_al_AJG_Preproof.pd
f).
[18] COVID-19 and the Digestive System Ma, Chunxiang MD1,2; Cong, Yingzi
PhD3,4; Zhang, Hu MD, PhD1,2Author Information. The American Journal of
Gastroenterology: July 2020 - Volume 115 - Issue 7 - p 1003-1006 doi:
10.14309/ajg.0000000000000691
[19] Patricia Sanz Segura, Yolanda Arguedas Lázaro, Sonia Mostacero Tapia, Tomás
Cabrera Chaves, Juan José Sebastián Domingo, Involvement of the digestive system
in COVID-19. A review, Gastroenterología y Hepatología (English Edition), Volume
43, Issue 8, 2020, Pages 464-471, ISSN 2444-3824,
https://doi.org/10.1016/j.gastre.2020.06.004
[20] https://www.thelancet.com/journals/langas/article/PIIS2468-1253(21)00076-
/5//fulltext, (additional appendix: https://www.thelancet.com/cms/10.1016/S2468-
1253(21)00076-5/attachment/495dfd0f-2eda-403b-b809-0c44a67e67b6/mmc1.pdf)
07/06/2021
[21] https://www.hopkinsmedicine.org/health/conditions-and-
diseases/coronavirus/coronavirus-kidney-damage-caused-by-covid19, 07/06/2021
[22] Hao-Long Zeng, Bo Zhang, Xu Wang, Qing Yang, Liming Cheng, Urinary trace
elements in association with disease severity and outcome in patients with COVID-19,
Environmental Research, Volume 194, 2021, 110670, ISSN 0013-9351,
https://doi.org/10.1016/j.envres.2020.110670
[23] https://www.ajmc.com/view/study-illustrates-kidney-impact-after-covid-19-
resolves, 07/06/2021
[24] https://ovarianresearch.biomedcentral.com/articles/10.1186/s13048-020-
00737-1, 07/06/2021
[25] Mauvais-Jarvis F, Klein SL, Levin ER. Estradiol, Progesterone,
Immunomodulation, and COVID-19 Outcomes. Endocrinology. 2020;161(9):bqaa127.
https://doi.org/10.1210/endocr/bqaa127. PMID: 32730568; PMCID: PMC7438701.
[26] Nesrein M. Hashem, Sameh A. Abdelnour, Ahmad R. Alhimaidi, Ayman A.
Swelum, Potential impacts of COVID-19 on reproductive health: Scientific findings
and social dimension, Saudi Journal of Biological Sciences, Volume 28, Issue 3, 2021,
Pages 1702-1712, ISSN 1319-562X, https://doi.org/10.1016/j.sjbs.2020.12.012
[27] Disser, Nathaniel P. BS1,*; De Micheli, Andrea J. PhD1,2,*; Schonk, Martin M.
MS1; Konnaris, Maxwell A. BS1; Piacentini, Alexander N. MS1; Edon, Daniel L. MS1;
Toresdahl, Brett G. MD1; Rodeo, Scott A. MD1; Casey, Ellen K. MD1; Mendias,
Christopher L. PhD, ATC1,2,aAuthor Information, Musculoskeletal Consequences of
COVID-19, The Journal of Bone and Joint Surgery: July 15, 2020 - Volume 102 -
Issue 14 - p 1197-1204 doi: 10.2106/JBJS.20.00847
[28] https://www.bmj.com/content/372/bmj.n617/rr-1, MJ 2021; 372 doi:
https://doi.org/10.1136/bmj.n617 (Published 03 March 2021), 07/06/2021
[29] R. Palcorresponding author1 and M. Banerjee2, COVID-19 and the endocrine
system: exploring the unexplored, J Endocrinol Invest. 2020 May 2 : 1–5. doi:
10.1007/s40618-020-01276-8
[30] Nalbandian, A., Sehgal, K., Gupta, A. et al. Post-acute COVID-19 syndrome. Nat
Med 27, 601–615 (2021). https://doi.org/10.1038/s41591-021-01283-z
[31] Yao X.H., Li T.Y., He Z.C. A pathological report of three COVID-19 cases by
minimally invasive autopsies. Zhonghua Bing Li Xue Za Zhi. 2020;49 PubMed.
[32] Devon E McMahon,a Antonia E Gallman, et al, Long COVID in the skin: a
registry analysis of COVID-19 dermatological duration. Lancet Infect Dis. 2021 Mar;
21(3): 313–314. Published online 2021 Jan 15. doi: 10.1016/S1473-3099(20)30986-5
[33] https://www.beckershospitalreview.com/patient-safety-outcomes/13-hospitals-
health-systems-that-have-launched-post-covid-19-clinics.html, 07/06/2021
[34] https://dig.abclocal.go.com/wls/documents/2020/072720-wls-covid-symptom-
study-doc.pdf, 07/12/2021
[35] Jorge Garza-Ulloa, Applied Biomedical Engineering Using Artificial Intelligence
and Cognitive Models, 1st Edition. Academic Press (Elsevier) August 2021, ISBN:
9780128207185
