16 November, 2005

100 years ago: Session 1905-06; Meeting IV - Sleeping Sickness

Sederunt 35
The Society met in the rooms of the Medical Club 22 Carlton Place on Thursday 16th November 1905 at 9 p.m.
The President, Professor Stockman, was in the chair, and in all 35 gentlemen were present.

I Minutes
The minutes of last meeting were read and approved.

II New Members
1. On the motion of the Chairman the ballot was dispensed with and Dr Edward J. Primrose was declared elected a member of the Society.
2. The Secretary read two proposals for membership viz.
Dr Wm. Barr Inglis Pollock 13 Belgrave Terrace
Proposed by Dr Alexander Morton.
Seconded by Dr John P. Duncan.
Dr John Paton, 21 Moray Place
Proposed by Dr James Hamilton.
Seconded by Dr James Weir.

III Captain Greig's paper
Captain Greig I.M.S. then gave a most interesting & full account of the researches on "Sleeping Sickness", conducted by the Royal Society's Commission in Uganda and the Nile Valley, and showed many lantern slides illustrative of his remarks.
A precis of the paper follows this minute.

At the close of Captain Greig's account the President moved a hearty vote of thanks to Captain Greig & this was at once heartily responded to. Professor Stockman also made some remarks on paracytic diseases carried by means of flies, and on the action of arsenic in improving and alleviating the condition of the patient in many diseases without actually bringing about a permanent cure.

Professor Muir then made a few remarks anent the absence of immunity even after the long course pursued by the disease; & in this connection said he thought innoculation would probably be useless. He then referred to Ehrlich's work on the aniline dyes and their action on paracytic diseases.

Drs McGilvray, Reid, Halliday, Burgess & Dunlop also took part in the discussion & asked various questions.

Captain Greig then replied to the questions and explained some points he had omitted to refer to in his account.
This was all the business.

Precis of Captain Greig's paper
The serious nature of the disease was first referred to. It is estimated that there have been 100,000 deaths from it since the outbreak of the epidemic in 1900, and there is the possibility of it spreading widely along trade routes. The geographical distribution of the disease was then spoken of. In the Uganda district it is found mainly on the shore and islands at the northern end of Victoria nyanza & affects a belt measuring from 10 to 15 miles from the shore. Until 5 or 6 years ago this was practically a closed district but since then caravans have opened it up & no doubt these serve to carry infection along the trade routes.

The symptomatology of the disease was next discussed. It may be divided into 3 stages, 1st onset with few or no symptoms 2nd stage of sleepiness & emaciation 3rd stage of sleep ending in death with extreme emaciation.

Stage 1. may be normal for 2 or 3 years.
Stage 2. Slight irregularity with slight fever.
Stage 3. Markedly subnormal for a week or two before death & may fall to the temperature of the surrounding air viz about 93° F.

Enlarged glands are present all over the body in the 2nd stage, & these are full of the paracyte of the disease.

The sleepy look appears on the face during the 2nd stage.
Emaciation always appears during the second stage & sometimes marked nervous symptoms also come on e.g. acute mania.
Profound sleep, from which however the patient may be roused by vigorous measures appears in the third stage & this is accompanied by extreme emaciation & always ends in death.

The blood contains the paracyte in the early stages of the disease and it is also present in the cerebrospinal fluid in the later stages.

Pathology of the disease.
The lymph glands both superficial & deep are enlarged & full of the paracyte. The Brain presents no special features macroscopically but microscopically there are crowds of leucocytes round the vessels & in the last stages streptococci are present. In both blood & cerebrospinal fluid there is a marked increase of mono-nucleated white cells. The stomach presents numerous small ulcers due to the digestion of submucous petechiae and in the heart numerous petechiae are also present.

Experimental work was carried out in a woodlined-iron laboratory. Monkeys were largely used for experiment.

Characteristics of the Paracyte.
It is a trypanosome & belongs to the flagellata. It reproduces itself by fission & sometimes it may divide more than once without separation of the new individuals from each other so that a rosette is formed.
It is an elongated fusiform body possessing nucleus, micro nucleus, a thin vibratory fin extending along its whole length and terminating in a simple flagellum the micro nucleus being at the opposite pole to the attachment of the flagellum. Vacuoles & what seem to be food particles are usually present & the organism is about 3 times the length of the diametre of a red blood corpuscle. Similar forms of trypanosomata are also found in various forms of cattle disease in Uganda & Abyssinia.

Large numbers of natives in the infected area and also in non infected areas were examined. The blood cerebrospinal fluid & gland juices were investigated. The details of the methods adopted in such examinations were discussed. It was found that from 50 to 70 % of the population in the affected area was infected & in the early stage of the disease, while in a large number of diseased & healthy natives examined in non infected areas no trypanosomata were found. A number of the infected cases were followed out. Some died in the 3rd Stage: some died of pneumonia: some are fairly well still, & some may recover, but no case of recovery from the 3rd Stage is known. The exact area of distribution of sleeping sickness was mapped out and in these areas a fly (Glossina Palpalis) was found to be abundant, while in the free areas it was absent. Imported cases dying in a fly-free area do not spread the disease for other biting flies cannot carry the paracyte & infect man. If one Glossina Palpalis bite an infected subject and take up from his blood a single Trypanosome the paracyte proliferates enormously in the stomach & the next man punctured by the fly's proboscis becomes infected. This fly does not flourish in the open but prefers the cooler & shadier forrest. Many of these flies were captured & after being fed on an infected subject were caused to bite a healthy monkey at varying periods after ingestion of the infective meal. It was found that 48 hours seemed to be the limit of infectivity of a fly after infection, but that the monkey bitten within that period always developed the disease. Flies freshly caught in the sleeping sickness area were proved to be infective.

Arsenic & aniline dyes in combination were used & have an effect in reducing the numbers of paracytes present in the body & no doubt prolong life, but relapses constantly occur. This part of the investigation is still being vigorously worked at. Many interesting slides were then shown to illustrate the type of country and mode of life there of natives & whites & finally it was explained with reference to animal trypansomiasis that wild animals, themselves immune, might contain in their blood thousands of trypanosomata and thus act as reservoirs of the disease.

In reply to the remarks made by various gentlemen it was explained that no doubt the greater care exercised by the whites, their greater resistance, and the wearing of clothes, were factors in the prevention of the disease in their case; but one white man, a gardener, had been infected & is at present in this country ill with the disease. The incubation period seems to be from 8 days to 3 weeks. Wild monkeys do not permit the fly to bite them & so escape the disease.
Ralph Stockman

Archive: Royal College of Physicians and Surgeons of Glasgow
Reference: GB 250 RCPSG 73/1/11 Minute Book No. 6

Further reading
Paul Ehrlich
Sleeping sickness
Glossina palpalis