What is COVID-19?
Since 2019, the phrase COVID-19 seems to be everywhere. People, news, friends and families are all talking about it. So, what is COVID-19? And what kind of illness is it?
Signs and Symptoms
Let’s start with the signs and symptoms of Covid-19. People with Coronavirus disease (COVID-19) can have several symptoms, ranging from mild symptoms to severe illness and death.1 Some might also have an asymptomatic or presymptomatic infection where they do not display any signs or symptoms consistent with the COVID-19 illness.5 Common symptoms of people with COVID-19 include cough, fever or chills, and difficulty breathing.1 Other possible symptoms are weakness, sore throat, loss of taste or smell and muscle pain.2 Symptoms may appear 2-14 days after exposure to the virus, according to the Centers for Disease Control and Prevention.3 The detrimental effect of Covid-19 might vary depending on the individual. Older people with underlying chronic illnesses, such as lung disease, heart failure and kidney disease, have a higher risk of developing more severe complications from COVID-19 compared to younger adults.4
Cause
Covid-19 is an illness caused by coronavirus 2 (SARS-CoV-2). The COVID-pandemic has had a disastrous impact on the world’s demographics, resulting in more than 6 million deaths as of March 2022.5 SARS-CoV-2 may have derived from an animal coronavirus, specifically from a bat host, which eventually acquired the ability for human-to-human transmission.13 The first available data about COVID-19 suggested animal-to-human transmission from wild animals in Wuhan’s Huanan Seafood Market.19, 20 Later, emerging data demonstrated the transmission of the virus between humans through droplets and direct contact.21 Several reports suggest that people who did not have direct contact with Huanan Seafood Market were infected with COVID-19.21 SARS-CoV-2 mainly attacks the respiratory and vascular systems.5 Vascular systems refer to vessels that carry blood throughout your body. The novel virus spreads through coughs and sneezes.22,23 The novel virus is highly contagious, and initially spread like wildfire across the world following the December 2019 outbreak in Wuhan, China, forcing the World Health Organization (WHO) to declare a global pandemic on 11 March 2020.5,13
Current Treatments
Currently, studies suggest various treatments to combat COVID-19, including antiviral medications and anti-inflammatory drugs.5 Antiviral medications are prescription medicines that fight against viruses in your body.33 Meanwhile, anti-inflammatory drugs are medicines that help relieve your pain and flu symptoms.34 The effectiveness of such treatments depends on the severity of the illness and certain risk factors.5
Several potential treatments have been proposed, authorized and approved to combat COVID-19.5 One of these is Paxlovid, which is a combination of two antiviral drugs.5 Research by Mahase found that patients with severe COVID-19 who received Paxlovoid treatment within three days of symptom onset have an 89% lower risk of COVID-19-related hospital admission or death compared to patients without Paxlovid treatment.6 The FDA authorized the use of Paxlovid for patients with mild to moderate Covid-19.6
Another antiviral medication potentially used for Covid-19 treatment is Remdesivir.6 Several studies elucidated the effectiveness of Remdesivir in shortening the time for adults to recover from mild-to-severe Covid-19 compared to patients who received no Remdesivir.36,37,38 However, another study suggested that Remdesivir has no significant effect on COVID-19 patients’ mortality, recovery time or length of hospital stay.39
Dexamethasone is also one of the treatments that may be effective in treating Covid-19.5 In the Randomized Evaluation of COVID-19 Therapy (RECOVERY) trial, some hospitalized patients who have or are suspected of having Covid-19 received dexamethasone (n=2104) while others received the usual care (n=4321).35 The trial demonstrated the incidence of death to be lower in the dexamethasone group compared to the usual care group on oxygen support but not in patients receiving no respiratory support. 35
Finally, the most important way to contain coronavirus is by getting vaccinated.5 Clinical researchers created several types of vaccines to combat COVID-19, such as Pfizer, Moderna, and Novavax.5 Vaccination is crucial to trigger our body to defend against disease and illnesses. 5
What is Ferritin?
Ferritin is a protein that stores iron, delivering it when the body needs it.7 Iron delivery is an essential and tightly regulated process, ensuring our body gets enough iron.8 Iron is a vital element that regulates the production of red blood cells (haemoglobin) and the transportation of oxygen in our bodies.9 Too little or too much iron may result in several diseases.8 Iron deficiency can lead to iron-deficiency anaemia. Anaemia occurs when the amount of red blood cells in the blood is low.9 Several factors can lead to anaemia, including low iron intake.9 Similarly, too much iron, termed hemochromatosis, might affect several organs such as the liver, pancreas, heart, thyroid, joints and skin.8,10 People with hemochromatosis usually do not display visible symptoms until adulthood.10 Patients often do not get diagnosed until it affects several systems in their body.10 Therefore, getting your iron status tested is crucial. A ferritin test can help your doctor measure how much iron you have in your body. Serum ferritin can act as an inflammatory marker. Your doctor will measure your serum ferritin concentration, a widely used indicator, to determine if you have iron deficiency or excess iron in your blood.11,12
What Happens to Ferritin Levels During COVID-19?
Recent studies support the relationship between ferritin levels and the severity of COVID-19 illness.17 For example, a study by Bozkurt et al. found that ferritin levels were the only significant predictor determining the severity of the disease.14 In the study, patients with severe COVID-19 had a higher ferritin frequency than those with mild COVID-19.14 Another study by Zhou et al. demonstrated elevated serum ferritin levels in non-survivor patients of Covid-19 upon hospital admission and throughout the hospital stay compared to patients who survived the disease.15 Furthermore, Chen et al. found that 63 out of 99 patients with COVID-19 from Wuhan Jinyintan Hospital had a high serum ferritin level above the normal range.16 A study from New Orleans also revealed elevated serum ferritin in autopsies of ten patients who died due to COVID-19.18 Therefore, serum ferritin levels might be associated with the severity of COVID-19 disease.
Is High Ferritin a Result of COVID-19 or a Mediator of it?
What is the Cytokine Storm in COVID-19?
First of all, what is cytokine? Cytokines are small proteins vital for the interactions and communication between cells in our body.24 They signal the immune system to do its job, which is to respond to health and disease in the body.25,26 Thus, cytokines play a vital role in protecting our bodies. There are several types of cytokines. One of them is pro-inflammatory cytokines. They play a role in producing inflammatory responses such as fever and protect our body from agents that cause disease.26
Cytokine storm also called cytokine storm syndrome(CSS), may occur when our body releases too many cytokines simultaneously into the blood.27,29 It can be harmful to our health.27 Cytokines storms are also characterized by the excessive activation of immune cells and the elevated amount of pro-inflammatory cytokines.30 If pro-inflammatory cytokines are produced in appropriate amounts, then the inflammatory responses are beneficial for our body. However, they can be harmful if they are produced in an excessive amount.26 An infection, autoimmune condition or other disease are some of the factors that can lead to a cytokine storm.27 Common signs and symptoms of a cytokine storm are high fever, inflammation (redness and swelling), severe fatigue and nausea.27 It can be fatal and lead to multiple organ failures.21, 27 Many studies have elucidated that some patients with severe COVID-19 might have cytokine storms. 28 It is hard to detect cytokines as they have a short life span and can be difficult to measure.43 Ferritin levels are possible markers widely used to detect cytokine storms.43
Does High Ferritin Cause it?
Several studies reported that patients with COVID-19 have a high level of ferritin and cytokines. A study also found elevated ferritin and cytokines in non-survivors compared to patients discharged from the hospital.15 The levels of ferritin and cytokines will increase as the patient’s condition worsens.15 Also, Liu et al. suggested that the frequency of ferritin and cytokines will decrease as patients start to recover, suggesting a relationship between the level of ferritin and cytokines.40
There is a complex relationship between ferritin and cytokine. Research suggested that cytokines induced ferritin production, leading to inflammation that causes cell damage.32,42 Therefore, it can be concluded that high ferritin levels might be due to the accumulation of cytokines.31 However, another study also suggested a high level of ferritin might increase the production of pro-inflammatory cytokines.32, 41
What are the Implications for COVID-19 Therapy?
As mentioned before, one of the life-threatening outcomes of COVID-19 is usually accompanied by cytokine storm syndrome.28 Therefore, some COVID-19 therapy is specifically used to treat cytokine storms. However, the effectiveness of the treatment still needs further study.
A study measuring the serum ferritin level as a marker for cytokine storm in Covid-19 patients found that their serum ferritin level was decreased when the patients were treated with Vitamin C and dexamethasone.42 The recovery rate of the patients was also found to be high.42
Dexamethasone is used to lower the higher level of cytokines produced.5 It can also be administered to patients with Remdesivir.5 However, the National Institutes of Health (NIH) Covid-19 Treatment Guidelines Panel does not recommend that patients with mild COVID-19 take dexamethasone.5 It can be considered for patients requiring hospitalisation or oxygen support.5
Summary
COVID-19 illness is not just the ordinary flu. It has caused a pandemic and devastated communities worldwide. It could result in detrimental immune effects such as cytokine storms. Cytokine storms in COVID-19 patients are also associated with a high ferritin level. The relationship between the release of ferritin and cytokines is complex; the release of ferritin might trigger the release of cytokines and vice versa. If left untreated, it can be harmful to the patients. Thus, several treatments, such as dexamethasone, are specifically used to treat cytokine storms.
References
- Esakandari H, Nabi-Afjadi M, Fakkari-Afjadi J, Farahmandian N, Miresmaeili SM, Bahreini E. A comprehensive review of COVID-19 characteristics. Biol Proced Online [Internet]. 2020 Aug 4 [cited 2022 May 31];22:19. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7402395/
- Lovato A, de Filippis C, Marioni G. Upper airway symptoms in coronavirus disease 2019 (COVID-19). Am J Otolaryngol [Internet]. 2020 Apr 4 [cited 2022 May 31];102474. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7128936/
- CDC. Coronavirus disease 2019 (COVID-19) – symptoms [Internet]. Centers for Disease Control and Prevention. 2022 [cited 2022 May 31]. Available from: https://www.cdc.gov/coronavirus/2019-ncov/symptoms-testing/symptoms.html
- Gómez‐Belda AB, Fernández‐Garcés M, Mateo‐Sanchis E, Madrazo M, Carmona M, Piles‐Roger L, et al. COVID‐19 in older adults: What are the differences with younger patients? Geriatr Gerontol Int [Internet]. 2020 Dec 2 [cited 2022 May 31];10.1111/ggi.14102. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7753273/
- Cascella M, Rajnik M, Aleem A, Dulebohn SC, Di Napoli R. Features, evaluation, and treatment of coronavirus(COVID-19). In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 [cited 2022 May 30]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK554776/
- Mahase E. Covid-19: Pfizer’s paxlovid is 89% effective in patients at risk of serious illness, company reports. BMJ [Internet]. 2021 Nov 8 [cited 2022 May 31];n2713. Available from: https://www.bmj.com/lookup/doi/10.1136/bmj.n2713
- Theil EC. Ferritin: the protein nanocage and iron biomineral in health and in disease. Inorg Chem [Internet]. 2013 Nov 4 [cited 2022 May 31];52(21):12223–33. Available from: https://pubs.acs.org/doi/10.1021/ic400484n
- Chiou B, Connor JR. Emerging and dynamic biomedical uses of ferritin. Pharmaceuticals (Basel) [Internet]. 2018 Nov 13 [cited 2022 May 31];11(4):124. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6316788/
- Abbaspour N, Hurrell R, Kelishadi R. Review on iron and its importance for human health. J Res Med Sci [Internet]. 2014 Feb [cited 2022 Jun 1];19(2):164–74. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3999603/
- Porter JL, Rawla P. Hemochromatosis. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 [cited 2022 Jun 1]. Available from: http://www.ncbi.nlm.nih.gov/books/NBK430862/
- Daru J, Colman K, Stanworth SJ, De La Salle B, Wood EM, Pasricha SR. Serum ferritin as an indicator of iron status: what do we need to know? Am J Clin Nutr [Internet]. 2017 Dec [cited 2022 Jun 1];106(Supplement 6):1634S-1639S. Available from: http://ajcn.nutrition.org/lookup/doi/10.3945/ajcn.117.155960
- VanWagner LB, Green RM. Elevated serum ferritin. JAMA [Internet]. 2014 Aug 20 [cited 2022 Jun 1];312(7):743. Available from: http://jama.jamanetwork.com/article.aspx?doi=10.1001/jama.2014.302
- Liu YC, Kuo RL, Shih SR. COVID-19: The first documented coronavirus pandemic in history. Biomedical Journal [Internet]. 2020 Aug [cited 2022 Jun 1];43(4):328–33. Available from: https://linkinghub.elsevier.com/retrieve/pii/S2319417020300445
- Bozkurt FT, Tercan M, Patmano G, Bingol Tanrıverdi T, Demir HA, Yurekli UF. Can ferritin levels predict the severity of illness in patients with covid-19? Cureus [Internet]. 2021 Jan 21 [cited 2022 Jun 2]; Available from: https://www.cureus.com/articles/48747-can-ferritin-levels-predict-the-severity-of-illness-in-patients-with-covid-19
- Zhou F, Yu T, Du R, Fan G, Liu Y, Liu Z, et al. Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study. The Lancet [Internet]. 2020 Mar [cited 2022 Jun 2];395(10229):1054–62. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0140673620305663
- Chen N, Zhou M, Dong X, Qu J, Gong F, Han Y, et al. Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study. The Lancet [Internet]. 2020 Feb [cited 2022 Jun 2];395(10223):507–13. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0140673620302117
- Vargas-Vargas M, Cortés-Rojo C. Ferritin levels and COVID-19. Revista Panamericana de Salud Pública [Internet]. 2020 Jun 1 [cited 2022 Jun 2];44:1. Available from: https://iris.paho.org/handle/10665.2/52235
- Fox SE, Akmatbekov A, Harbert JL, Li G, Quincy Brown J, Vander Heide RS. Pulmonary and cardiac pathology in African American patients with COVID-19: an autopsy series from New Orleans. The Lancet Respiratory Medicine [Internet]. 2020 Jul [cited 2022 Jun 2];8(7):681–6. Available from: https://linkinghub.elsevier.com/retrieve/pii/S2213260020302435
- Zhou P, Yang XL, Wang XG, Hu B, Zhang L, Zhang W, et al. A pneumonia outbreak associated with a new coronavirus of probable bat origin. Nature [Internet]. 2020 Mar 12 [cited 2022 Jun 2];579(7798):270–3. Available from: http://www.nature.com/articles/s41586-020-2012-7
- Guo YR, Cao QD, Hong ZS, Tan YY, Chen SD, Jin HJ, et al. The origin, transmission and clinical therapies on coronavirus disease 2019 (COVID-19) outbreak – an update on the status. Military Med Res [Internet]. 2020 Dec [cited 2022 Jun 2];7(1):11. Available from: https://mmrjournal.biomedcentral.com/articles/10.1186/s40779-020-00240-0
- Ragab D, Salah Eldin H, Taeimah M, Khattab R, Salem R. The covid-19 cytokine storm; what we know so far. Front Immunol [Internet]. 2020 Jun 16 [cited 2022 Jun 2];11:1446. Available from: https://www.frontiersin.org/article/10.3389/fimmu.2020.01446/full
- Zhao S, Zhuang Z, Ran J, Lin J, Yang G, Yang L, et al. The association between domestic train transportation and novel coronavirus (2019-nCoV) outbreak in China from 2019 to 2020: A data-driven correlational report. Travel Medicine and Infectious Disease [Internet]. 2020 Jan [cited 2022 Jun 2];33:101568. Available from: https://linkinghub.elsevier.com/retrieve/pii/S1477893920300181
- Wang X, Pan Z, Cheng Z. Association between 2019-nCoV transmission and N95 respirator use [Internet]. Infectious Diseases (except HIV/AIDS); 2020 Feb [cited 2022 Jun 2]. Available from: http://medrxiv.org/lookup/doi/10.1101/2020.02.18.20021881
- Zhang JM, An J. Cytokines, inflammation, and pain. International Anesthesiology Clinics [Internet]. 2007 [cited 2022 Jun 2];45(2):27–37. Available from: https://journals.lww.com/00004311-200704520-00004
- Cytokines and their side effects [Internet]. [cited 2022 Jun 2]. Available from: https://www.cancer.org/treatment/treatments-and-side-effects/treatment-types/immunotherapy/cytokines.html
- Arango Duque G, Descoteaux A. Macrophage cytokines: involvement in immunity and infectious diseases. Front Immunol [Internet]. 2014 Oct 7 [cited 2022 Jun 2];5. Available from: https://doi.org/10.3389/fimmu.2014.00491
- Https://www. Cancer. Gov/publications/dictionaries/cancer-terms/def/cytokine-storm [Internet]. 2011 [cited 2022 Jun 2]. Available from: https://www.cancer.gov/publications/dictionaries/cancer-terms/def/cytokine-storm
- Mehta P, McAuley DF, Brown M, Sanchez E, Tattersall RS, Manson JJ. COVID-19: Consider cytokine storm syndromes and immunosuppression. The Lancet [Internet]. 2020 Mar [cited 2022 Jun 2];395(10229):1033–4. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0140673620306280
- Tang Y, Liu J, Zhang D, Xu Z, Ji J, Wen C. Cytokine storm in covid-19: The current evidence and treatment strategies. Front Immunol [Internet]. 2020 Jul 10 [cited 2022 Jun 2];11:1708. Available from: https://www.frontiersin.org/article/10.3389/fimmu.2020.01708/full
- Tisoncik JR, Korth MJ, Simmons CP, Farrar J, Martin TR, Katze MG. Into the eye of the cytokine storm. Microbiol Mol Biol Rev [Internet]. 2012 Mar [cited 2022 Jun 2];76(1):16–32. Available from: https://journals.asm.org/doi/10.1128/MMBR.05015-11
- Shaw TY, Schivo M. Weathering a cytokine storm: a case of ebv-induced hemophagocytic lymphohistiocytosis. Journal of Investigative Medicine High Impact Case Reports [Internet]. 2016 Apr 1 [cited 2022 Jun 3];4(2):232470961664740. Available from: http://journals.sagepub.com/doi/10.1177/2324709616647409
- Rosário C, Zandman-Goddard G, Meyron-Holtz EG, D’Cruz DP, Shoenfeld Y. The Hyperferritinemic Syndrome: macrophage activation syndrome, Still’s disease, septic shock and catastrophic antiphospholipid syndrome. BMC Med [Internet]. 2013 Dec [cited 2022 Jun 3];11(1):185. Available from: https://bmcmedicine.biomedcentral.com/articles/10.1186/1741-7015-11-185
- CDC. What you should know about flu antiviral drugs [Internet]. Centers for Disease Control and Prevention. 2021 [cited 2022 Jun 3]. Available from: https://www.cdc.gov/flu/treatment/whatyoushould.htm
- Nsaids [Internet]. nhs.uk. 2017 [cited 2022 Jun 3]. Available from: https://www.nhs.uk/conditions/nsaids/
- The RECOVERY Collaborative Group. Dexamethasone in hospitalized patients with covid-19. N Engl J Med [Internet]. 2021 Feb 25 [cited 2022 Jun 3];384(8):693–704. Available from: http://www.nejm.org/doi/10.1056/NEJMoa2021436
- Goldman JD, Lye DCB, Hui DS, Marks KM, Bruno R, Montejano R, et al. Remdesivir for 5 or 10 Days in Patients with Severe Covid-19. N Engl J Med [Internet]. 2020 Nov 5 [cited 2022 Jun 3];383(19):1827–37. Available from: http://www.nejm.org/doi/10.1056/NEJMoa2015301
- Spinner CD, Gottlieb RL, Criner GJ, Arribas López JR, Cattelan AM, Soriano Viladomiu A, et al. Effect of remdesivir vs standard care on clinical status at 11 days in patients with moderate covid-19: a randomized clinical trial. JAMA [Internet]. 2020 Sep 15 [cited 2022 Jun 3];324(11):1048. Available from: https://jamanetwork.com/journals/jama/fullarticle/2769871
- Beigel JH, Tomashek KM, Dodd LE, Mehta AK, Zingman BS, Kalil AC, et al. Remdesivir for the treatment of covid-19 — final report. N Engl J Med [Internet]. 2020 Nov 5 [cited 2022 Jun 3];383(19):1813–26. Available from: http://www.nejm.org/doi/10.1056/NEJMoa2007764
- Zhang R, Mylonakis E. In inpatients with COVID-19, none of remdesivir, hydroxychloroquine, lopinavir, or interferon β-1a differed from standard care for in-hospital mortality. Ann Intern Med [Internet]. 2021 Feb [cited 2022 Jun 3];174(2): JC17. Available from: https://www.acpjournals.org/doi/10.7326/ACPJ202102160-017
- Liu T, Zhang J, Yang Y, Ma H, Li Z, Zhang J, et al. The potential role of IL-6 in monitoring the severe case of coronavirus disease 2019 [Internet]. Infectious Diseases (except HIV/AIDS); 2020 Mar [cited 2022 Jun 3]. Available from: http://medrxiv.org/lookup/doi/10.1101/2020.03.01.20029769
- Kernan KF, Carcillo JA. Hyperferritinemia and inflammation. International Immunology [Internet]. 2017 Nov 1 [cited 2022 Jun 3];29(9):401–9. Available from: https://academic.oup.com/intimm/article/29/9/401/3852570
- Burugu HR, Kandi V, Kutikuppala LVS, Suvvari TK. Activities of serum ferritin and treatment outcomes among covid-19 patients treated with vitamin c and dexamethasone: an uncontrolled single-centre observational study. Cureus [Internet]. 2020 Nov 11 [cited 2022 Jun 3]; Available from: https://www.cureus.com/articles/45108-activities-of-serum-ferritin-and-treatment-outcomes-among-covid-19-patients-treated-with-vitamin-c-and-dexamethasone-an-uncontrolled-single-center-observational-study
- Fajgenbaum DC, June CH. Cytokine storm. New England Journal of Medicine [Internet]. 2020 Dec 3 [cited 2022 Jun 3];383(23):2255–73. Available from: https://doi.org/10.1056/NEJMra2026131
- Nhs.uk. 2022. [online] Available at: <https://www.nhs.uk/ipgmedia/National/Lymphoma%20Association/assets/Anaemia.pdf> [Accessed 20 July 2022].