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Preventing a covid-19 pandemic

BMJ 2020; 368 doi: (Published 28 February 2020) Cite this as: BMJ 2020;368:m810

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Re: Preventing a covid-19 pandemic - COVID-19: Vitamin D deficiency; and, death rates; are both disproportionately higher in elderly Italians, Spanish, Swedish Somali, and African Americans? A connection? Research urgently required!

Dear Editor

It is posited by contributors [1, 2, 3, 4, 5] to BMJ, ‘Preventing a covid-19 pandemic’, others, [6, 7, 8] and myself, [9] that vitamin D, and particularly vitamin D deficiency, is a likely factor in the progression, and/ or severity, and/ or mortality of COVID-19; and also may present clinical treatment opportunities.

My preprint, ‘Vitamin D deficiency: a factor in COVID-19, progression, severity and mortality? – An urgent call for research’, [9] posits, greater vitamin D deficiency <25nmol/L in southern (E.g. Spain and Italy), than northern European Countries (E.g. Germany, Norway, Finland, Iceland), may help account for differentials, in mortality rates per million. Consistent with this, Northern Europeans have higher vitamin D food intakes, food fortification, and supplement more. This is an easily testable posit.

Northerly resident; Europeans with darker skins; BAME, and African Americans; as well as more southerly elderly Spanish and Italians; are often vitamin D deficient. IF, vitamin D deficiency, increases the risk of COVID-19 related; infection, hospitalisation and mortality; one would expect, and indeed sees, higher COVID-19 hospitalisation and mortality, in; dark-skinned (Fitzpatrick scale) northerly residents; those with dress codes that inhibit sunlight; and generally in groups likely to include the ‘D’ deficient.

Whilst data is still sparse, it supports the above contention; albeit lack of distancing, and vitamin D deficiency, may both be contributing factors; for example: “40 % of the reported COVID-19 related deaths occurring in Stockholm involve the Somali diaspora communities”; yet they only represent 0.84% of the population] [10, 11, 12, 13] Data clearly shows, Somalis, and wider immigrant groups, are D deficient, for example, “Vitamin D deficiency ( < 25 nmol/l) was found in 73% of the Somali women and in 1% of the controls” [14, 15, 16]

In respect of African Americans, a headline, April 3rd, 2020, states, ‘Early Data Shows African Americans Have Contracted and Died of Coronavirus at an Alarming Rate [17] “In Chicago, 70% of COVID-19 Deaths Are Black,” [18] The review, APHA ‘Call for Education and Research Into Vitamin D Deficiency/Insufficiency’, in 2008, noted, “84% of African American men and women (over 65) were vitamin D deficient.” [19, 20, 21] (‘D’ deficiency definitions vary).

In contrast, in continental Africa, whilst Vitamin D deficiency exists, it does not appear to be as widespread as in the United States: “one in five people living in Africa had a low 25(OH)D concentration with use of a less than 30 nmol/L.” [22] COVID-19 data for Somalia is limited. Tests are done externally: current data; 7 cases, 1 recovered, no deaths. [23] The first recorded case was confirmed on the 16th of March. Twenty volunteer doctors from Somali National University went to Italy to help fight COVID-19 there. [24, 25] Case numbers in wider Africa are currently relatively low, compared to the most infected countries, but arguably there is insufficient data, or certainty, as to initial infection dates, to, at this point, even postulate as to future COVID-19 infection, or mortality rates, in Africa. [26]

Differences appear to exist in the metabolism of Vitamin D; ‘The D paradox’; [27] between Caucasians and African Americans, particularly in terms of bone density. However, the metabolism of vitamin D is complex, and pathways impacting COVID-19 likely differ from those regulating bone densities.

The COVID-19 mortality rate, has very sadly, been high in Italy (15,887 as at 5th April 2020). [28] A rapid response to the BMJ titled ‘Re: Preventing a covid-19 pandemic Can high prevalence of severe hypovitaminosis D play a role in the high impact of Covid infection in Italy? ’[29] notes, “700 women aged 60-80 yrs in Italy had values of 25OH vitamin D lower than 5 ng/ml in 27% of the women and lower than 12 ng/ml in as many as 76%.” [29]

BAME (Black, Asian, Minority Ethnic) persons in the United Kingdom, may be more susceptible. A UK study of 2,249 patients by the ‘Intensive Care National Audit and Research Centre’, noted “Despite making up just 13 per cent of the UK population, a third of patients who fall critically ill with COVID-19 are from black, Asian or minority ethnic (BME) groups.” [30] Further, sadly, 6 out of 8, UK COVID-19 medical staff deaths, were British Muslims.[31] Hasidic Jews in Israel may also be at higher COVID-19 risk, due to failure to isolate[32] and/ or greater risk of vitamin D deficiency.[33, 34]

Arguably it is urgent, that research is done, to determine if vitamin D deficiency factors in COVID-19, infection, progression, severity and mortality. Vitamin D blood spot tests are cheap. Patient records have to be maintained in any event. The additional work, and risk burden, in taking vitamin D measurements are limited. However, the reward could be very significant, even a ‘game changer’.

Further, any determination that vitamin D factors in COVID-19, incidence progression and outcome, would point to the likelihood of COVID-19 following a seasonal pattern in populations, which would require factoring into determination of Governmental COVID-19 forward planning policies; mortality risk modelling; social distancing polices; and population vitamin D optimisation, including access to outside spaces, to facilitate sensible, ethnicity appropriate, exposure to UVB in sunlight; and/ or free ‘D’ supplementation, at least for the most vulnerable and financially insecure.

COVID-19 studies might comprise:
• Test all COVID-19 patients in hospital/s at a given point in time for Vit D, follow, and report results.
• Take finger prick samples at the same time as COVID-19 test – follow through with laboratory vitamin D tests on the samples of all positives, and an equal number of controls; report results.
• A study using Vit D clinically – test for low vit D – where low supplement with vitamin D3, and/ or as an alternative to above, try a 1,25-active form; [35] report results.

Vitamin D, could usefully be immediately incorporated into wider clinical nutritional COVID-19 protocols, [36, 37] but, to better understand the role of vitamin D in COVID-19; for the formulation of; treatment, prevention, and wider, policies; the above studies would still be urgently required.

1. Rhein, H. (6th March 2020). BMJ 2020;368:m810 doi:
2. Cobbold, P. (2nd March 2020). BMJ 2020;368:m810 doi:
3. Maestri, E., Formoso, G., Da Cas R., Mammarella, F,. Trotta, F. (12th March 2020)
Vitamin D against COVID 19: Clinicians need more than observations and hope. BMJ 2020;368:m810 doi:
4. Grant, W. (1st April 2020). Can vitamin D supplementation reduce the spread of COVID-19? Try first with health care workers and first responders.: BMJ 2020;368:m810 doi:
5. Cobbold, P. (8th March 2020). BMJ 2020;368:m810 doi:
6. McCartney, D., Byrne, D. (2020). Optimisation of Vitamin D Status for Enhanced Immuno-protection Against Covid-19. Issue: Ir Med J; Vol 113; No. 4; P58.
7. Grant, W., Lahore, H., McDonnell, S., Baggerly, C., French, C., Aliano, J., & Bhattoa, (30th March 2020 2nd version) H. Evidence that Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths. Nutrients 2020, 12, 988.
8. Isaia, G. (25th March 2020). Possibile ruolo preventivo e terapeutico della vitamina D nella gestione della pandemia da COVID-19 Enzo Medico, Università degli Studi di Torino, Torino,
9. Brown, R. Sarkar, A. (29th Feb. 2020 – submitted 24th). Vitamin D deficiency: a factor in COVID-19, progression, severity and mortality? – An urgent call for research. Preprint.
10. Speckhard, A., Mahamud O., Ellenberg M. (April 3, 2020). When Religion and Culture Kill: COVID-19 in the Somali Diaspora Communities in Sweden (Retrieved 5th April 2020).
11. McElroy, D. (April 5th, 2020). Sweden is making a dangerous bet on a 'cultural cure' to Covid-19 N opinion. (Retrieved 5th April 2020).
12. Stockholm Wikipedia. (Retrieved 6th April 2020). "Statistisk arsbok for Stockholm 2018" (PDF). Statistik Stockholm. (Retrieved 5 October 2018).
13. Somalis in Sweden Wikipedia. (Retrieved 6th April 2020).
14. Demeke, T., Osmancevic, A., Gillstedt, M., Krogstad, A., Angesjö, E., . . . & Landin-Wilhelmsen, K, (2019). Comorbidity and health-related quality of life in Somali women living in Sweden, Scandinavian Journal of Primary Health Care, 37:2, 174-181, DOI:10.1080/02813432.2019.1608043
15. Bergstro, ̈ I., Palme, ́M., Persson, J., & Blanck, A. Observational study of vitamin D levels and pain in pregnant immigrant women living in Sweden. Gynecol Endocrinol, 2014; 30(1): 74–77. 2014 Informa UK Ltd. DOI: 10.3109/09513590.2013.856408
16. Islam, M., Viljakainen, T., Kärkkäinen, M., Saarnio, E., Laitinen, K., & Lamberg-Allardt, C. (2011). Prevalence of vitamin D deficiency and secondary hyperparathyroidism during winter in pre-menopausal Bangladeshi and Somali immigrant and ethnic Finnish women: associations with forearm bone mineral density Br J Nutr. 2012 Jan;107(2):277-83. doi: 10.1017/S0007114511002893. Epub 2011 Aug 9.
17. Johnson, A., Buford, T. (April 3rd 2020). Early Data Shows African Americans Have Contracted and Died of Coronavirus at an Alarming Rate. No, the coronavirus is not an “equalizer.” Black people are being infected and dying at higher rates. Here’s what Milwaukee is doing about it — and why governments need to start releasing data on the race of COVID-19 patients. ProPublica. (Retrieved 5th April 2020)
18. Zamudio, M., Ramos, E. (5th April 2020). In Chicago, 70% of COVID-19 Deaths Are Black. (Retrieved 6th April).
19. APHA. (2008). Call for Education and Research Into Vitamin D Deficiency/Insufficiency Policy Number: 20081 (Retrieved 5th April 2020).
20. Freeland, A. (2019). African-Americans At Greatest Risk of Vitamin D Deficiency. Pediatrics. 2009 Mar;123(3):797-803. doi: 10.1542/peds.2008-1195.
21. Saintonge, S., Bang, H., & Gerber, et Al. (2009). Implications of a new definition of vitamin D deficiency in a multiracial us adolescent population: The National Health and Nutrition Examination Survey III. Pediatrics. Mar;123(3):797-803. doi: 10.1542/peds.2008-1195.
22. Mogire, R., Mutua, A., Kimita, W., Kamau, A., Bejon, P., … & Atkinson, S. (2019) Prevalence of vitamin D deficiency in Africa: a systematic review and meta-analysis The Lancet Volume 8, ISSUE 1, Pe134-e142. DOI:
23. Worldometer. Somalia Coronavirus. (Retrieved 6th April 2020).
24. 2020 coronavirus pandemic in Somalia Wikipedia. (Retrieved 6th April 2020).
25. Dhaysane, M. (27th March 2020). Somalia sending 20 doctors to help Italy fight virus. Doctors from Horn of Africa nation will help fight against coronavirus in Italy. Anadolu Agency. (Retrieved 6th April 2020).
26. 2020 coronavirus pandemic in Africa. Wikipedia. (Retrieved 6th April 2020).
27. Brown, L., Cohen, B., Tabor, D., Zappalà, G., Maruvada, P., Coates, P. (2018). The vitamin D paradox in Black Americans: a systems-based approach to investigating clinical practice, research, and public health - expert panel meeting report. BMC Proc 12, 6.
28. 2020 coronavirus pandemic in Italy. Wikipedia. (Retrieved 6th April 2020)
29. Giustina, A. Rapid response to Watkins J. Preventing a covid-19 pandemic. BMJ 2020;368:m810.
30. Boyd, C. (6th April 2020) Coronavirus warning for people from black and minority backgrounds as NHS data suggests they are at more risk of life-threatening complications. MailOnline. (Retrieved 7th April 2020)
31. El-Bar, K. (3rd April 2020). British Muslim nurse dies after contracting coronavirus. 6 out of 8 of deaths from coronavirus so far in UK's National Health Service have been British Muslims. (Retrieved 5th April 2020).
32. Halbfinger, D. (30th March 2020). Virus Soars Among Ultra-Orthodox Jews as Many Flout Israel’s Rules Failure to comply with government restrictions is causing the coronavirus to spread in ultra-Orthodox communities up to eight times faster than elsewhere in Israel. New York Times. (Retrieved 5th April 2020).
33. Tsur, A., Metzger, M., Dresner-Pollak, R. (2011). Effect of different dress style on vitamin D level in healthy young Orthodox and ultra-Orthodox students in Israel. Osteoporos Int. Nov;22(11):2895-8. doi: 10.1007/s00198-010-1492-y.
34. Mukamel, M., Weisman, Y., Somech, R., Eisenberg, Z., Landman, J., Shapira, I, Spirer, Z., Jurgenson U. (2001). Vitamin D Deficiency and Insufficiency in Orthodox and Non-Orthodox Jewish Mothers in Israel. Isr Med Assoc J. Jun;3(6):419-21.
35. Yang, J,. Zhang, H., Xu, Z. (2016). Effect of Vitamin D on ACE2 and Vitamin D receptor expression in rats with LPS-induced acute lung injury. DOI: 10.3760/cma.j.issn.1671-0282.2016.12.016
36. Caccialanza, R., Laviano, A., Lobascio, F., Montagna E., ... & Cereda E. (2020). Early nutritional supplementation in non-critically ill patients hospitalized for the 2019 novel coronavirus disease (COVID-19): Rationale and feasibility of a shared pragmatic protocol. In Press, Journal Pre-proof, Available online 3 April 2020
37. Barazzoni R et al., (2020). ESPEN expert statements and practical guidance for nutritional management of individuals withSARS-CoV-2 infection, Clinical Nutrition,

Competing interests: No competing interests

07 April 2020
Robert A Brown
McCarrison Society
St Lawrence, Jersey. C.I.