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TYPHUS IMMUNISATION

THE LANCETI ONDON : SATURDAY, NOVE1VIBER 29, 1941

THE war has now entered countries where exanthe-matic typhus is both endemic and epidemic and wherefrequent and efficient delousing will be difficult if notimpossible to carry out. Typhus is endemic on theRussian front from the Caucasus to Finland, althoughepidemic proportions have not yet been reached.Much of the disease described in the English news-papers as typhus is undoubtedly typhoid, which inGerman is known as typhus abdominalis. Neverthe-less there seems to be an urgent need for effectiveimmunisation if the history of the Serbian army inthe last war is not to be repeated. On a later pagewill be found a note on the precautions regarded bythe Ministry of Health as essential should infectedlice reach this country.

Unfortunately little is yet known about typhusimmunisation on a large scale. The only vaccinewhich has been in use for any considerable time is thatof WEIGL. This is made from the intestines of liceinfected with typhus rickettsiae inoculated per rectum.Three to four injections of the vaccine are necessaryto produce immunity while some hundreds of lice arerequired for the immunisation of one person. Apartfrom the delicate technique of rectal injection thismethod therefore requires a large staff of immunes onwhom the lice can be nourished. It is thus hardlypractical unless a whole institute is devoted solely tothe manufacture of the vaccine, as was done at Lwowunder the direction of Professor WEIGL. It is knownthat WEIGL remained when the Russians occupiedthis town in 1939 but nothing has been heard of hisfate and that of his institute since the beginning of the. Russo-German conflict. The only other method ofimmunisation used on a large scale has been the

injection of living murine typhus rickettsiae in Moroccoand Tunis. These rickettsiae, when living, un-doubtedly immunise against exanthematic typhusbut often at the expense of an attack of murine typhuswhich though not so deadly as the exanthematicform is not to be despised. The use of living murinerickettsiae as a vaccine is also contra-indicated incountries where lice are widely distributed in thepopulation, for then the stage is set for the possibleconversion of murine into exanthematic typhusrickettsiae by passage through the louse. The possi-bility of using killed murine typhus rickettsiae hasbeen envisaged by RUIZ CASTANEDA, who findsthat in guineapigs multiple doses do produce someimmunity. On another page Dr. G. M. FINDLAYshows from personal experience that the converse isalso to some extent true, and that at any rate apartial immunity is produced in man against murinetyphus by killed exanthematic typhus rickettsiae.In dealing with exanthematic typhus, however,it seems far better to employ the killed homo-logous rickettsiae, provided these can be obtained insufficient quantities. Two methods have recentlybeen put forward for obtaining antigenically rich

1. Ruiz Castaneda, M. Brit. J. exp. Path. 1941, 22, 167.

vaccines of exanthematic typhus rickettsiae. Cox 2

has injected rickettsiae into the yolk sacs of developingchick embryos while DURAND and GiROouD 3 haveinstilled rickettsiae intranasally into mice. From the

yolk sac or the mouse lung, after treatment withformalin or phenol, vaccines may be obtained contain-ing very large amounts, of killed rickettsipe. Toconfer immunity, however, it seems essential to givefour or five injections. Both, these. vaccines havebeen employed on a small scale in man but their actualvalue as immunising agents is at present unknown.Cox’s egg-yolk vaccine was employed during the recentsmall epidemic in Spain but the results are as yetunpublished. It is known that laboratory workerswho have been immunised by the egg-yolk vaccinehave subsequently become infected with exanthe-matic typhus ; in these cases of course there was pro-bably a more intense infection and a longer exposurethan is likely to occur under conditions in the field.A drawback to the use of the mouse lung vaccine isobviously the possibility that other viruses present inthe mouse lung may remain active in the presence ofthe disinfectant employed. This possibility may bereduced by employing special laboratory-bred strainsof mice.

Before typhus immunisation is attempted on a largescale in the field certain fundamental questions mustbe answered-what is the minimum number of injec-tions that produces immunity and the length of timefor which immunity persists, and what are the keepingproperties of the vaccine ? In immunising largenumbers of people it is not easy to ensure that allreceive four or five injections at intervals of 5-7 days,so that if possible the number of injections should bereduced to one or two. In regard to the duration ofimmunity it is known that with Weigl’s louse vac- *cine, as with the tick vaccine prepared against RockyMountain spotted fever, reinoculation every year isessential. Incidentally in testing immunity relianceshould not be placed solely on the Weil-Felix reaction ;the agglutination test and the demonstration ofrickettsicidal antibodies by the intiadermal injectionin rabbits, as devised by GIROUD,4 should also beemployed.. Finally there is already evidence thatafter 5-6 months in the ice-chest both Weigl’svaccine and the mouse-lung vaccine lose much of theirantigenic power. Presumably if kept at room

temperatures their loss of antigenicity would be’evenmore rapid. ,

INDUSTRY’S CLAIM ON MEDICINE" THE months that lie immediately before us," says

the Minister of Labour, " will be as crucial a period asthat of the Battle of Britain," and he has appealed toindustry to increase its output by 30 or 40 per cent.His appeal is a challenge to the medical profession,and in particular to those doctors who having appoint-ments in factories can help to ensure optimum effort:The question of optimum hours, Mr. BEViN has said,is not so much one of bargaining between trade-unionsand employers as one demanding a scientific approachwhich takes account of all the factors involved at anygiven time and recognises the need for adjustment asthose factors change. Surely one scientific approach2. Cox, H. R. Publ. Hlth Rep. Wash. 1938, 53, 2241.3. Durand, P. and Giroud, P. Arch. Inst. Pasteur Tunis, 1940, 29,

25, 234.4. Bull. Soc. Path. exot. 1938, 29, 25; 31, 245.

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must be that of medicine as a whole, the combinedwisdom of all who have the privilege of supervisingthe health of the workers. The effects of abnormalhours on health are known ; they have just been setout 1 again with authority by a select committee, butwe need more observations on the effects of differentwork spells. Admittedly, excessive overtime for along period has a devastating effect on the humanreserve of strength, both physical and mental. Overshort spells of a month or two, or even three as afterDunkirk, effort can be greatly intensified withoutcollapse. But over six months, the precise periodmentioned by Mr. BEVIN, it would be folly to drivefactory workers blindly, without regard to rest andrecreation. Production is by no means directlyproportional to the number of hours worked ; the

optimum hours for regular output are far less thanthose which can be maintained in a spurt. The

problem with which we are faced is to find the correctwork spell for each group of workers, for each gang,for each process, for each department, and for eachfirm. Fatigue, that scientifically vague yet expressiveword used to sum up the results of overwork, can atpresent only be measured in terms of output ; if

fatigue appears in the individual, in the squad, in thegang, in the shop, then production falls. And because

fatigue is cumulative it follows that the national effortmust decline if the rules so truly laid down by theHealth of Munition Workers Committee in the lastwar, and amply confirmed by later experience, are notapplied by those in authority.How is this to be done ? The first step is to apply

existing knowledge and this is now, we are assured,the firm intention of the Government as stated in the

report mentioned above and summarised last week inthese columns (p. 648). No longer is the accumulatedwisdom of the Industrial Health Research Board andits forerunners in regard to the relation of workinghours to output, tested again and again and provedright every time, to be set aside by the producingdepartments. Patriotism is not enough ; we can beruthless with materials but not with the human toolsthat fashion them. To ensure the perfect adaptationof workers to their work would no doubt require anindustrial medical service with a code and practice aselaborate as (say) that of the school medical service.But, as the B.M.A. report published today insists,an adequate medical service does not necessarilyinvolve an elaborate and expensive organisation.Last year’s order of the Ministry of Labour paved theway by giving the Factory Inspectorate discretion tointroduce doctors, nurses and welfare officers into anyfactory engaged on armament work. There shouldbe, says this report, in every factory, large or small,arrangements for the medical supervision of theworkers. Before the war there were in this countrysome 520 factories employing a thousand or moreworkpeople, and 137,000 employing less than 250.It should be possible for a group of smaller firms tocooperate in appointing a medical officer who will

spend his whole time in industrial medical work; andthere is much to be said for having some advisorybody to help the employer get the kind of medicalofficer who can safely be given a free hand when1. Statement relating to Production, being the 25th report of the

Select Committee on National Expenditure. H.M. Stat.Office. 6d.

2. Report of Committee on Industrial Health in Factories. B.M.A.House. Pp.43. 6d.

appointed. The proper placing of workers accordingto their fitness, their continued supervision underworking conditions after return from illness, studyof the occupational hazards and the best way to meetthem, a careful watch on the beginnings of psycho-neuroses-these form the background of a job whichmight well become as attractive as ’that of the public-school famulus. And to become this the worksmedical officer must be left to develop his style un-hindered, with direct access to the management whenhe needs it. The Association of Industrial MedicalOfficers has also devised a training scheme which itregards as practicable even in war-time, by whichspecial university committees, including doctors,employers and trade-union officials shall arrangecourses in industrial medicine and obtain facilities for

entry into all kinds of factories. Actually the interestof the general practitioner in the subject is beingmuch quickened these days and there is a good pros-pect, if the war goes on long enough, of the doctorregaining the intimate knowledge of his patients’daily lives that he lost when they entered the erst-while gloomy portals of the factory. This new aware.ness will provide the clue to the " research " which isregarded as something apart and out of the questionat present. Its essential basis will be what industriallife’looks like to doctors who move freely within it.

PHOTOGRAPHY THROUGH THEPERITONEOSCOPE

As early as 1901 the abdominal viscera of a dogwere seen through a cystoscope introduced into apneumoperitoneum. Since then the peritoneoscopehas been much improved, and the latest triumph is theperfection of a method of colour photography whichmakes it possible to attach a coloured picture of hisabdominal organs to the patient’s clinical notes. Yetthe enthusiasts for peritoneoscopy are still few, andthere seem to be three reasons for this lack of favour :the procedure may be accounted unsafe ; its scopemay be too limited; or the alternative (usuallyexploratory laparotomy) may be considered so muchmore satisfactory that any added risk is consideredworth while. From published accounts the dangersof peritoneoscopy do not seem alarming. GARREY 1

has reported 75 peritoneoscopies without a complica-tion, except for slight sepsis in the abdominal wall ofone case. His patients were, on an average, 36 hoursin hospital. He discusses the experience of otherobservers, notably of RUDDOCK, who has completed1500 examinations, and concludes that peritoneos-copy has only a fraction of the mortality of laparo-tomy, while it saves money and hospital beds. Thefirst part of the operation is the induction of a

pneumoperitoneum. An area in the midline of theabdominal wall about 5 cm. across, just below theumbilicus, is anaesthetised by procaine infiltration.An incision 1-5 cm. long is made through the skin, anda small blunt trocar and cannula are inserted throughwhich the pneumoperitoneum is induced. The

larger cannula which is to act as the sheath forthe optical instrument is introduced through a nickin the anterior fascia. GARREY gives as the essentialsfor the patient’s comfort during the proceduregentleness in all movements-no jolting and no

touching of visceral surfaces by the instrument. He

1. Garrey, W. E. New Engl. J. Med. 1941, 225, 180.