onchocerciasis in both hemispheres

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appear to be bacillary rather than coccal in form,measuring approximately 0-1-0-2 by 03-05 .e.Similar granular masses were occasionally seen in thecytoplasm of nerve and glial cells and more rarelyin the endothelial cells of capillaries and the mono-nuclear cells infiltrating the meninges and braintissue, from which it would seem that the virus

multiplied both in cytoplasm and nucleoplasm, thoughmore commonly in the latter medium. Accordingto these investigators, the typical acidophil inclusionsrepresent a later stage of the infection arising in viruscolonies as the result of agglutination and fusionof virus particles-a degenerative process in fact-and they go so far as to say that the presence ofhomogeneous acidophil inclusions in a cell is a signthat the cell is resisting the infection satisfactorily.Whether or not one agrees with Nicolau and

Kopciowska in this interpretation of the fully formedinclusion, and probably many would dispute it,they have certainly brought forward strong evidencethat herpes virus forms colonies in the nuclei andmore rarely in the cytoplasm of the cells which itinfects. While awaiting confirmation of this workwe can congratulate our French colleagues on a mostinteresting paper.

ONCHOCERCIASIS IN BOTH HEMISPHERES

INVESTIGATIONS were undertaken by Prof. RichardP. Strong and his colleagues in 1934 into tropicaldiseases in remote parts of the Belgian Congo, andtheir report on this research, so far as it concerns

onchocerciasis, has now been published.l In 1926-27

Strong visited Liberia and the Belgian Congo, andbetween these two African expeditions his workcovered onchocerciasis in Central America.The first part of the monograph compares the

disease as found in the two hemispheres. Althoughonchocerciasis as a blinding disease was first generallyappreciated in America-indeed it was essentiallyfor that reason that the late Prof. F. Fiilleborn raisedthe American parasite to specific rank as Onclaoce7cccemeutiepts-the amount of blindness produced by0. volvulus among Bantus and Pigmies in the partof Africa lying between 5° and 6° South latitude and23° and 24° East longitude is far more tragiceven than in Central America. In the regionwhere the expedition settled, every inhabitant

they examined-and they examined all but a few-had the infection ; and at the clinics therewere led to them daily several hundred blind

persons who waited with patience in the sun untiltheir time came to be examined. Moreover the

degree of individual infection was great ; for whereasin America and other parts of Africa it was unusualto find 5 or 6 nodules in any person, in Kassende25 to 100 were not uncommonly demonstrated.In Guatemala the incidence of infection among thosesimulium flies which transmit the infection was

never more than 5 per cent., but in this African areait was 33 per cent. The blindness is caused by micro-filariae getting into the eye ; they are, at least

commonly, born within the nodules in which thehost’s reticulo-endothelial tissue has imprisonedtheir parents ; their numbers lessen in a piece ofsnipped-off skin as the distance of its site fromnodules increases ; and in persons who have becomeblind there are nearly always nodules on or close tothe head. Strong is unconvinced, however, that thenodule signifies the spot where the simulium fed and

1 Onchocerciasis in Africa and Central America. By Richard P.Strong, Jean Hissette, Jack H. Sandground, and Joseph C.Bequaert, Amer. J. trop. Med. 1938, 18, No. 1, Suppl.

the’ infective larvae entered the man ; he points outthat nodules are found particularly where lymphaticsconverge, or where there is pressure, or where boneis prominent-his inference perhaps being that inthese spots an infective larva wandering in the sub-cutaneous tissue meets an obstruction and settlesdown. In America it has been amply shown thatremoval of nodules is a valuable method of lesseningthe amount of infection in localities where thesimulium has a limited range and where the infectionis correspondingly circumscribed. In Africa, with

heavy fly infection and no such circumscription, itis felt that the first step in prevention must be oneof sanitary engineering ; and its necessary extent is

sufficiently indicated by the fact that these simuliumflies have twice invaded Kampala in Uganda, thoughtheir nearest breeding places are believed to be45 miles away. It is thought likely, too, that antelopecan act as a host alternative to man, and that theremay be onchocerciasis without the tissue reactionin the’host which produces nodules. In the mono-graph under review the ocular conditions are ablydealt with by Dr. Jean Hissette of the Congo Govern-ment Service, whose conclusions are that the ultimatecause of onchocercal blindness is atrophy of the

optic nerve and that much more elaborate examina-tions will have to be made before we have a truepicture of the various pathological changes involved.J. K. Sandground deals in the main with the

systematic position of this and allied parasites andreaches the conclusion that locally the parasitedepends entirely on human beings for its maintenanceand spread. J. C. Bequaert thinks that the twentyknown species of simulium in the Belgian Congoare only a fraction of those that inhabit that vast andvaried territory.

These writers make clear how much more investiga-tion is needed. There seems little doubt howeverthat understanding will be inadequate so long as

this important problem is treated as something apart,and is not linked with the results of research intoother filarial infections and the host reactions to

them. Such comparisons can hardly fail to affordmutual enlightenment.

P.F.O.

IMPROVEMENT in anaesthetics and the ways of givingthem has created a more personal relationship betweenpatient and anaesthetist. As Dr. H. B. Wilson 1

regretfully observes, however, in hospitals the twoparties seldom become acquainted until they meetin the operating theatre, a situation that need notarise in private practice. The effect on the patientof a personal assurance from the anaesthetist that allwill be well is very valuable, and such an assuranceshould constitute an essential part of every " preparefor operation." The increased use of sedatives,hypnotics, and basal narcotics are other measures thatcontribute to the patient’s peace of mind and make theoperation less of an ordeal. Where surgical shockis likely to follow operation, Dr. Wilson advocatesthe prophylactic injection of intravenous glucoseand insulin, as recommended by Fisher, and hecondemns once more the starving and purgingwhich, though less common than formerly, are still toooften a part of hospital and nursing-home routine.Starvation, coupled with anxiety, causes metabolicdisturbance in nervous patients ; drastic purgatives

1 In St. Thomas’s Hospital Reports. Edited by Prof.O. L. V. S. de Wesselow, Mr. C. Max Page, assisted by Mr. N.R.Barrett, Dr. J. St. C. Elkington, and Dr. A. J. Wrigley.Second Series. Vol. II. St. Thomas’s Hospital, London. 1937.Pp. 271.

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