Silicosis and silicotuberculosis: Ancient diseases that are still not conquered

Full text

AJTCCM VOL. 29 NO. 3 2023 105
EDITORIAL
When the history of ‘miners’ phthisis’ (silicotuberculosis) is
described, authors oen refer to the classical writings of the Greek
physician, Hippocrates (460 - 370 BC), who described breathlessness
in persons exposed to dust in mines and stone quarries. However,
these diseases have been recognised since more ancient times. e
Egyptians depicted the respiratory tract anatomy in texts dating
back to the 30th century BC.[1] Using modern paleopathological
techniques, evidence of silicosis and tuberculosis can be found in
civilisations across the world.
Silicotic nodules were observed in the lungs of Egyptian mummies,
presenting on autopsy with ‘areas of diuse and nodular brosis’.[2] In
auent individuals from that time (for whom mummication was
available), this lung pathology is generally thought to result from silica
exposure during sandstorms.[3] However, quarry mining and stone
masonry were common occupations back then, and these occupations
are associated with silicosis even in modern times. As long ago as the
Neolithic period, int miners (using deer antlers as picks and ox tibias
for making axes for mining) probably suered from silicosis.[4] On
the European continent, silicosis has recently been described in ‘Ötzi’,
aglacier mummy who lived more than 5 000 years ago.[5]
Compared with the evidence for silicosis, ancient tuberculosis
evidence is even more prevalent, since it can be detected in bony
tissues, which survive for much longer than pulmonary tissues as
a viable source for diagnosis. Large numbers of cases have been
identied based on the morphology of the spine (‘Pott’s disease’)
dating back to the Roman period and the Middle Ages. Nerlich
and Lösch[6] reviewed the paleopathology of tuberculosis, citing
numerous examples of the diagnosis being made based on spinal
lesions seen in specimens dating back to the Neolithic period
(approximately 3 000 - 7000 BC), such as a frequently cited article
byMorse and Brothwell[7] on tuberculosis in ancient Egypt. Even
molecular diagnoses (identifying Mycobacterium tuberculosis DNA)
were made on European skeletal remains and Egyptian mummies
dated to the same periods.[6,8,9] Similarly, polymerase chain reaction
testing for M.tuberculosis was positive when testing bone samples
from a woman and infant who were buried at the (now submerged)
site of Atlit-Yam, o the coast of Israel – dating back more than 9000
years ago.[10]
Since early times, interventions to prevent these diseases were
proposed. In a 1556 publication, Georgius Agricola[11] recommended
proper ventilation to remove dust and quoted Pliny (from Roman
times) recommending the use of respiratory protection by covering
the face with animal bladder-skin to limit exposure to dusts. In the
same publication, he vividly describes the grim picture of the impact
of silicotuberculosis on young individuals: ‘the dust has corrosive
qualities, it eats away the lungs, and implants consumption in the
body; hence in the mines of the Carpathian Mountains women are
found who have married seven husbands, all of whom this terrible
consumption has carried off to a premature death’. Yet, despite
these early recommendations to prevent silicosis, Ramazzini[12] still
described the problem of silicosis in stone cutters 150 years later, in
1705. Another two centuries later, in 1902, the Chamber of Mines
in Johannesburg was still looking for ways to obviate or minimise
the occurrence of miners’ phthisis, and invited practical suggestions
and plans for combating the causes, oering monetary rewards
for the best practical suggestions and devices.[13] Now, more than
another century later, national tuberculosis and silicosis elimination
programmes have been implemented as recommended by the World
Health Organization and the International Labour Organization as
part of the Global Programme for the Elimination of Silicosis.[14]
However, eliminating dust exposure is dicult, and it is clear that
small-scale mining, artisanal mining and other entities outside of the
formal mining industry may not be able to reach national prevention
targets.[15]
Although the article by Dennis et al.[16] on silicosis in northern
Tanzania in this issue of AJTCCM does have some epidemiological
shortcomings (as pointed out by the authors), their study clearly
highlights the fact that (although these diseases have been known
for many millennia) we have not yet been able to curb their impact
on the human population. Certain populations (such as small-scale
mining employees) are impacted disproportionately, as was found in
the drainage area of this Tanzanian hospital. Previous studies have
indeed conrmed that small-scale miners in Tanzania are exposed
to very high levels of silica dust.[17] Even remote populations may be
aected if mines employ migrant workers – another group that is
disproportionally aected.[18]
Aected employees and their families have the right to be supported
and compensated if an occupational disease is diagnosed. South
Africa (SA) was the rst country in the world to compensate silicosis
and tuberculosis as occupational diseases.[19] Nevertheless, a large
proportion of ex-mineworkers in SA still suffer uncompensated
disease.[18,20] Despite legal imperatives for reporting, many medical
practitioners diagnosing silicosis and tuberculosis fail to recognise
the occupational link and even refuse to complete relevant claim
documents, leaving compromised employees and their families in
dire situations.
Previous silica exposure, even in the absence of radiological
silicosis, is known to increase the risk of developing tuberculosis.[21] In
SA, ‘silicotuberculosis’ (tuberculosis diagnosed in an individual with
radiological silicosis) is listed as an occupational disease in Schedule3
of the Compensation for Occupational Injuries and Diseases Act
(COIDA).[22] is means that silicotuberculosis is legally presumed
to have occurred as a result of employment, in terms of section 66 of
COIDA. Just a few months ago (May 2023), updated compensation
criteria were published in SA, specifying that if an employee was
exposed to free crystalline silica in the workplace for 2 years, and they
are diagnosed with tuberculosis in the next 12 months, it is considered
an occupational disease – even in the absence of radiological evidence
of silicosis. In any employee with silica dust exposure of 15 years or
more (without radiological silicosis), a diagnosis of tuberculosis is now
always considered a compensable occupational disease, irrespective of
the time since last exposure.[23]
Silicosis and silicotuberculosis: Ancient diseases that are still
notconquered

106 AJTCCM VOL. 29 NO. 3 2023
EDITORIAL
All cases of occupational disease should be referred to an
occupational health practitioner, who can assist with completion of
the compensation documentation, but (more importantly) assess the
workplace and implement appropriate preventive measures to protect
the other employees too.
W A J Meintjes, MB ChB, PGDip (Occ Med), FCPHM (SA) Occ
Med, MMed (Occ Med)
Head: Occupational Medicine, Tygerberg Hospital, Western Cape Department
of Health and Wellness, Cape Town, South Africa; Senior Lecturer, Division of
Health Systems and Public Health, Department of Global Health, Faculty of
Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
wajm@sun.ac.za
1. Kwiecinski J. Images of the respiratory system in ancient Egypt: Trachea, bronchi and
pulmonary lobes. Can Respir J 2012;19(5):e33-e34. https://doi.org/10.1155/2012/640292
2. Cockburn A, Baracco RA, Reyman TA, Peck WH. Autopsy of an Egyptian mummy.
Science 1975;187(4182):1155-1160. https://doi.org/10.1126/science.187.4182.1155
3. Tapp E, Curry A, Aneld C. Sand pneumoconiosis in an Egyptian mummy. Br Med J
1975;2(5965):276. https://doi.org/10.1136/bmj.2.5965.276-b
4. Shaw AB. Knappers’ rot: Silicosis in East Anglian flint-knappers. Med Hist
1981;25(2):151-168. https://doi.org/10.1017/s0025727300034359
5. Nerlich AG, Vigl EE, Fleckinger A, Tauber M, Peschel O. e Iceman: Life scenarios
and pathological ndings from 30 years of research on the glacier mummy ‘Ötzi’.
Pathologe 2021;42(5):530-539. https://doi.org/10.1007/s00292-021-00961-6
6. Nerlich AG, Lösch S. Paleopathology of human tuberculosis and the potential
role of climate. Interdiscip Perspect Infect Dis 2009;2009:437187. https://doi.
org/10.1155/2009/437187
7. Morse D, Brothwell DR, Ucko PH. Tuberculosis in Ancient Egypt. Am Rev Respir Dis
1964;90:524-541. https://doi.org/10.1164/arrd.1964.90.4.524
8. Masson M, Molnár E, Donoghue HD, et al. Osteological and biomolecular evidence of
a 7000-year-old case of hypertrophic pulmonary osteopathy secondary to tuberculosis
from Neolithic Hungary. PLoS ONE 2013;8(10):e78252. https://doi.org/10.1371/
journal.pone.0078252
9. Donoghue HD, Lee OY, Minnikin DE, Besra GS, Taylor JH, Spigelman M. Tuberculosis
in Dr Granville’s mummy: A molecular re-examination of the earliest known Egyptian
mummy to be scientically examined and given a medical diagnosis. Proc Biol Sci
2010;277(1678):51-56. https://doi.org/10.1098/rspb.2009.1484
10. Hershkovitz I, Donoghue HD, Minnikin DE, et al. Detection and molecular
characterization of 9000-year-old Mycobacterium tuberculosis from a Neolithic
settlement in the Eastern Mediterranean. PLoS ONE 2008;3(10):e3426. https://doi.
org/10.1371/journal.pone.0003426
11. Agricola G. De Re Metallica. Translated from the rst Latin Edition of 1556 by Hoover
HC and Hoover LH. https://www.gutenberg.org/les/38015/38015-h/38015-h.htm
(accessed 25 August 2023).
12. Breathnach CS. Bernardino Ramazzini and his treatise of the diseases of tradesmen.
Ir J Med Sci 2000;169:68-71. https://doi.org/10.1007/bf03170493
13. The prevention of miners’ phthisis. Br Med J 1902;2(2181):1276. https://doi.
org/10.1136/bmj.2.2181.1276
14. Fedotov I. e ILO/WHO Global Programme for the Elimination of Silicosis. Occup
Health South Afr 2006;12(1):4-7.
15. Brouwer DH, Rees D. Can the South African milestones for reducing exposure to
respirable crystalline silica and silicosis be achieved and reliably monitored? Front
Public Health 2020;8(107):1-13. https://doi.org/10.3389/fpubh.2020.00107
16. Dennis E, Mussa H, Sanga MP, Howlett P, Nyakunga G. Afr J orac Crit Care Med
2023;29(3):e269. https://doi.org/10.7196/AJTCCM.2023.v29i3.269
17. Bratveit M, Moen BE, Mashalla YJ, Maalim H. Dust exposure during small-scale
mining in Tanzania: A pilot study. Ann Occup Hyg 2003;47(3):235-240. https://doi.
org/10.1093/annhyg/meg027
18. Ehrlich R, Barker S, Montgomery A, Lewis P, Kistnasamy B, Yassi A. Mining migrant
worker recruitment policy and the production of a silicosis epidemic in late 20th-century
southern Africa. Ann Glob Health 2023;89(1):25. https://doi.org/10.5334/aogh.4059
19. McCulloch J. Medicine, politics and disease on South Africa’s gold mines. J South Afr
Stud 2013;39(3):543-556. https://doi.org/10.1080/03057070.2013.818850
20. McCulloch J, Miller P, eds. Mapping and resolving a health crisis: 1902 - 1929. In:
Mining Gold and Manufacturing Ignorance: Occupational Lung Disease and the
Buying and Selling of Labour in Southern Africa. Singapore: Palgrave Macmillan,
2023:55-79. https://link.springer.com/content/pdf/10.1007/978-981-19-8327-6.pdf
(accessed 25 August 2023).
21. Ehrlich R, Akugizibwe P, Siegfried N, Rees D. e association between silica exposure,
silicosis and tuberculosis: A systematic review and meta-analysis. BMC Public Health
2021;21(1):953. https://doi.org/10.1186/s12889-021-10711-1
22. Department of Labour, South Africa. Compensation for Occupational Injuries and
Diseases Act No. 130 of 1993, as amended. Amendment of Schedule 3 of Act No. 130
of 1993. Government Gazette No. 35164, 2012. (Published under Government Notice
235). https://www.gov.za/sites/default/les/gcis_document/201409/35164gen235.pdf
(accessed 25 August 2023).
23. Department of Employment and Labour, South Africa. Compensation for Occupational
Injuries and Diseases Act, 1993 (Act No. 130 of 1993). Regulations on pulmonary
tuberculosis associated with silica dust exposure for the compensation fund made by
the Minister under Compensation for Occupational Injuries and Diseases Act, 1993.
Government Gazette No. 48518, 2023. (Published under Government Notice 3365).
https://www.gov.za/sites/default/les/gcis_document/202305/48518rg11579gon3365.
pdf (accessed 25 August 2023).
Afr J Thoracic Crit Care Med 2023;29(3):e1495.
https://doi.org/10.7196/AJTCCM.2023.v29i3.1495