ANKYLOSTOMA (MINERS’ WORM). 293 
thoroughly and energetically, but it has not been found possible com- 
pletely to eradicate the worm. The number of infected men has been 
greatly reduced, but a small percentage remains who still harbour the 
worm. This small percentage remains about the same in spite of the con- 
tinuance of treatment, and is, of course, always capable of introducing 
the disease into any fresh mine or of reinfecting the mine to any extent 
if preventive measures were relaxed. 
Before considering the probability of the spread of Ankylostoma in 
this country it is necessary to point out that we have hardly any definite 
information as to its complete absence at the present time. Only one case 
of the disease has been recorded in a British coal-mine, but the worm may 
well be present to a limited degree without causing obvious illness. A 
latent infection of this kind, owing to some small change in the tem- 
perature or the moisture of a mine, may increase to a serious epidemic 
at any time, or may be carried to other pits where more favourable 
conditions may lead to the most disastrous results. No evidence of the 
presence of the worm has been found in the few collieries which have been 
systematically examined, but it must not be assumed too readily that it is 
completely absent. 
Is there a Probability of Ankylostoma becoming established in 
British Coal-mines ? 
(A) Possible Sources of Infection. 
(1) The worm is endemic among the general population in nearly 
all tropical and sub-tropical countries (Southern Asia, Africa, 
South America, West Indies, &c.) and parts of North America, 
Australia, and in Europe south of the Alps, and in Hungary. 
(2) It is present among underground workers in the Westphalian 
coalfield and in the French and Belgian coal-mines. 
(3) It is present in the Cornish tin-mines, at any rate in the Cam- 
borne district. 
The infection may thus be easily introduced into this country from 
the tropics and Southern Europe by returned miners, or even by those 
who have not followed any underground employment abroad (soldiers, 
navvies, &c.); and from Germany, Belgium, France, and the Cornish 
mines by underground workers. Cases have been recorded in Lanarkshire 
and in Belfast in the persons of soldiers, and in the former case a man 
was actually working as a miner when his illness attracted attention. 
A large number of Poles are employed in the Lanarkshire coalfield, some 
of whom may have worked in Westphalia or Hungary, and Italians 
have lately been introduced into a metalliferous mine in the North of 
England. 
(B) Conditions found wndergrownd in British Coal-mines which 
would influence the establishment of the Worm. 
The conditions of temperature on the surface are such that practically 
the worm cannot spread among the ordinary population in this country. 
In summer the eggs may hatch and the larve develop to the infective 
stage in the open air, but any small danger which might arise from this 
source is rendered negligible by the almost universal use amongst all 
classes in this country of arrangements for the proper disposal of excreta. 
