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PASTEURISATION OF MILK IN THE U.S.A.

IT is now more than 30 years since Mr. NathanStraus, of New York, began his campaign in favour ofmilk rendered safe by heat. In 1908 he was stillfighting for adequate pasteurisation and against com-mercial pasteurisation by the " flash " process. Atthat time his definition of adequate pasteurisation wasthe exposure of the milk to 157 ° F. for 20 minutes,followed by rapid cooling, whereas by the " flash "process the milk was exposed to varying temperaturesabove and below 160° F. for perhaps a minute. TheU.S. Public Health Reports (Feb. llth, 1927) showthat 28 of the milk-borne outbreaks of infectiousdiseases recorded during the last 18 years were

attributed to inadequately pasteurised milk. The sameissue expresses the belief of the U.S. Public HealthService " that pasteurisation of milk is the most potentsingle force operating to prevent the transmission ofmilk-borne diseases," and states that the service is atpresent engaged in a study of apparatus in order toassist milk-control officials to formulate properdefinitions and to secure improved methods. Theissue of the reports for April 29th carries the mattera stage further. It indicates that flash pasteurisationhas disappeared from the scene, and that the majorityof State definitions of pasteurisation specify a tempera-ture of 142° F. or 145° F. and a holding time of30 minutes. The difficulties of securing the desiredresult are considerable. Even if the thermometerstands at the specified level for 30 minutes it is notcertain that every particle of milk will reach therequired temperature owing to cold pockets, foam,valve leakage, and unsatisfactory devices forindicating and controlling temperature and time.The inspector may not have all the technical informa-tion necessary to make the theoretical definitioneffective. Should the definition require an

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approvedapparatus " the local health officer would have toemploy a sanitary engineer. And if every particle ofthe milk has to be pasteurised a higher margin of heatmay have to be adopted which will interfere with thecream line, and interference with the cream line willproduce serious public opposition to the universal useof pasteurised milk. Illustrations are given in thereport of the modified apparatus designed to meet thesedifficulties. While the tests carried out by the PublicHealth Service have disclosed many defects these have,we learn, promptly been made good for the most partby modifications made on the spot without theapparatus being returned to the manufacturer.

This report should be of great value to those whohave the supervision of pasteurisation in this country.We doubt if the British public is sufficiently interestedin safe milk as yet. In reply to a question in Parlia-ment on May 25th it.was stated that there are nowonly 120 pasteurising establishments in England andWales complying with the Ministry of Health’sregulations and their definition that " pasteurisedmilk " must be retained at a temperature of not lessthan 145 ° F. and not more than 150’F. for at least30 minutes and must then be cooled immediately toa temperature of not more than 55° F. We have heardof milk dealers who have installed a "holder"apparatus, but do not apply for a licence because theyfind that their customers are not interested in thequestion of adequately pasteurised milk. Anotherpoint arises in view of the American experience.A fee of 21 Is. is paid in respect of each plant. Doesthis imply that the local authority which grants thelicence takes any responsibility with regard to theefficiency of the plant ? Or, on the other hand, havewe adopted the principle that the public healthauthorities are to judge the efficiency of the plantsolely by the periodical bacterial examinations of themilk treated ? It is obvious that the regulation thatmilk must " not be pasteurised more than once "cannot be enforced either by inspection of the plantor by examination of the milk. Furthermore, it doesnot seem probable that the officials in this country,whose duty it is to inspect the apparatus before thelicence is granted, are better equipped with technical

information than their colleagues in the U.S.A. Allthings considered, we cannot expect to get very farwith voluntary methods, and ultimately, when furtherexperience has been gained, it may be necessary toenforce pasteurisation of all milk except the two uppergrades (Certified and Grade A (T.T.))if we really wishto secure a safe milk-supply for a public that is notenthusiastic either for or against but rather expectssuch matters to be arranged for it by the statutorypublic health authorities.

BLOOD GROUPING IN EUROPE AND AMERICA.

THE nomenclature of blood groups was discussed ata meeting of the Health Committee of the League ofNations, of which a report has just been issued. Dr.T. Madsen, the President, pointed out that there weredifferences between the nomenclature adopted inEurope and America, and the Committee had beenasked to secure international uniformity. The maindifficulty was that the problem was not one forgovernmental regulation, though in a certain numberof countries-notably Denmark-it was receivingofficial attention. There seemed to be no need tohold an international conference, since the question wasnot so much one of technique as of form. Corre-spondence would go some way towards defining thedifficulties, and eventually a small number of personsmight be called together to examine the possibilitiesof agreement. It was decided that the Section ofHygiene should investigate the problem on these lines.

CARBON TETRACHLORIDE IN THE TREATMENTOF DISTOMIASIS IN SHEEP.

CARBON tetrachloride was first used as an anthel-mintic in animals in 1921 by M. C. Hall, then seniorzoologist to the U.S. Bureau of Animal Industry, 1who, in conjunction with Shillinger, in 1923showed the drug to be an efficient and fairly saferemedy against certain nematodes in the alimentarycanal. In 1922 this drug was used by Jeffreys inAmerica against intestinal flukes in foxes, andin 1925 and 1926 was experimentally used in theBritish Isles for liver fluke (Fasciola hepatica) in sheep,by J. H. Norris in Ireland and R. F. Montgomeriein Wales. Since the publication of this experimentalwork large scale field trials have been made in thisand other countries, and reports of the results arebeing awaited with interest. The drug has beenshown to be very efficacious against the adult flukesin the bile-ducts of the liver, but, like extract ofmale fern, it has no effect upon the immature flukesin the liver parenchyma (the F. hepatica reaches thebile-ducts by direct penetration of the fluke embryothrough Glisson’s capsule). These immature formsbecome mature and are laying eggs in the bile-ductsin the -fourth week after dosage, and consequentlyfurther dosage is necessary to destroy them. A doseof 1 c.cm. of carbon tetrachloride in gelatin capsulewithout previous starvation is sufficient to clear adultflukes from the bile-ducts of the sheep and, speakinggenerally, sheep will tolerate as much as 30 or 40 c.cm.of the drug in capsule. It is well to note, however,that in occasional instances flocks have been foundwhich tolerate carbon tetrachloride badly and deathshave resulted. This is a matter which is now underinvestigation in Great Britain. In the meantime itbehoves those who are about to use the drug uponsheep to try a few sheep first and find out how thedrug is tolerated by the particular flock before dosinglarge numbers. Carbon tetrachloride possessesadvantages in that sheep can be treated withoutpreliminary starvation and can be dosed even whenheavy in lamb or with lambs at foot. If furtherexperiments can explain the reasons why carbontetrachloride should prove toxic in some flocks andnot in others, and if this toxicity can be avoided bysome simple means, the drug will probably replaceextract of male fern as a remedy for the cure of

1 THE LANCET, 1922, ., 391.

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distomiasis in sheep. The presence of impuritieshas been held by many workers to account for thevariations in toxicity. Its application to human

parasites was the subject of considerable discussionin 1924.2 M. Khalil, working in Egypt, has beenattempting to discover whether the toxicity isattributable to sulphur impurities. Harold Kinghas found carbon bisulphide in samples submittedto him for testing by the Medical Research Council,but in experimental animals Khalil found thata mixture of carbon tetrachloride and carbon bisul-phide had no ill-effects. He is inclined to attributethe toxicity to the presence of sulphur compoundsother than CS2 and gives directions for getting ridof impurities in commercial samples. During 1924he says that 80,000 people were treated at the Govern-ment hospitals by this drug without any fatalities.

PHILOSOPHY.

COMMON experience has amply shown that ineducation there are two disciplines which haveconspicuous merit in helping the mind to learn to thinkaccurately. One is the attempt to find the exactequivalent of the ideas of one nation in the language ofanother, which is translation. The other is to discovera coherent interpretation of human experience whichcan be expressed in words, which is philosophy.And anyone knows that medicine is as much in needas any subject of accurate thought and a nice appre-ciation of the meaning of words. Two years ago theBritish Institute of Philosophical Studies was foundedwith the special object of establishing a link betweenthe professional philosophers and the educatedpublic, and its second annual meeting was held onJuly 4th. The President is the Earl of Balfour, thechairman of council Prof. L. T. Hobhouse, the deputychairman the Master of Balliol; the council is a longlist of distinguished and respected names. Thereare some 1600 members and more than 500 enrolledfor the courses of lectures which were given lastwinter, among which we notice a series on

" MedicalPsychology " by Dr. T. W. Mitchell. The Institutealso publishes a quarterly journal from 88, Kingsway,London, W.C. 2, and obviously deserves the supportof those who are seriously interested in intellectualprogress. ____

THE COST OF NOISE.

THE report on harmful noise, which Prof. H. J.Spooner submitted to the International FatigueCommittee of the American Society of IndustrialEngineers on May 26th, should serve to keep attentionfixed on this important subject, and contains manyobservations of general interest. He believes that themost serious aspect of the problem has hitherto notbeen considered ; this is the loss due to impairment ofefficiency in industrial life, more particularly by inter-ference with men of affairs and principals, whosecapacity for clear thinking and hard work is perceptiblyweakened by the babel of noise. He estimates thatthe economic loss due to this kind of wastage mayconceivably be a great deal over a million pounds aweek in this country alone ; and though this figuremay well be an over-estimate, no one will deny thatthe attempt to do mental work in noisy and distractingsurroundings tends to lower efficiency and produceirritability. The uproar of mechanically-propelledtraffic and of other machinery in our streets is themost serious source of noise, and the noisy environ-ment of hospitals, nursing homes, and schools calls forearnest attention. Prof. Spooner believes that themost nerve-shattering sound in our streets is causedby tramway-cars ; he considers that these vehicleshave lost most of the reasons for their existence sincethe introduction of motor omnibuses, and points outthat they are being gradually scrapped and are doomedto ultimate extinction. Here, perhaps, the thought isbut the offspring of the wish, in which many motorists

2 THE LANCET, 1924, ii., 715.3 Ibid., 1926, i., 549.

must share from ulterior motives. He makes otherrecommendations of interest to motorists-namely,that noisy ramshackle motor vehicles should be warnedoff the streets, that motor horns should be standardisedto a low melodious pitch, that louder hooters shouldonly be used in emergencies, and that " driving-on-the-hoot " should be prohibited. Such reforms areundoubtedly desirable, though difficult to enforce, anda beginning ought to be made in the attempt todiminish the uproar of the streets. The furtherproposal is made that the pneumatic rock-drills, usedfor breaking up roads, should not be permitted intowns, and certainly not in the vicinity of hospitalsand schools. In factories and works, Prof. Spoonerurges, designers of machinery should pay more atten-tion to the balancing of rotating parts, particularly ofthose working at high speed, and to the mounting ofcertain machinery on antivibration supports ; noisymachinery means excessive wear and waste of power,and the noise tends to reduce the productive powersof the workers and may be a cause of accidents. Wehope that the movement for the reduction or preven-tion of harmful noise will achieve its object byawakening public opinion.

THE PREVENTION OF DENGUE.

THOUGH not in itself serious, dengue is a veryuncomfortable disease, and causes a considerable lossof service. During 1925 818 cases were reportedfrom the army in India ; no statement is made asto the average time lost, but in naval cases during theprevious year it was eight days. The incidence of thedisease at Aden is discussed by Major G. H. Divein the Journal of the Royal Army Medical Corpsfor April. After examining the clinical records of thestation for the last few years, he concludes that thereis a short term fever endemic there, appearing everysummer, and always dengue though often otherwisenamed. The troops become infected from April toJuly, afterwards acquiring a considerable degree ofimmunity, perhaps lasting two years, so that the infec-tion only becomes prevalent again if a new regimenthas reached Aden later than July. Major Diveascribes dengue to the abundantly present mosquito9 edes argenteus. though the local fever is sometimescalled sand-fly fever, he has never seen a case of thatdisease at Aden, nor has he seen a phlebotomus there.An epidemic of dengue occurred at Saigon in 1926,

very fully and instructively reported by Dr. R. Pirot,a surgeon in the French Navy,! special attentionbeing given to the cases on his own ship, Craonne(125 men). She reached Saigon from France inFebruary, and on April 25th one of the crew returnedfrom leave at Cape St. James and slept on the upperdeck, unprotected by a mosquito net. On April 28thhe sickened with what was later found to be dengue.As Dr. Pirot suggests, the subsequent history isilluminated by the work of Siler, Hall, and Hitchens.2Female Abdes egypti (stegomyia fasciata) no doubtbit the first patient; after 11 days they becameinfective and bit other men of the ship who developeddengue from four to six days later. Sixteen casescame under notice between May 15th and 31st. InJune dengue spread to other ships and establishmentsand Dr. Pirot saw 130 cases in the hospital; 80 percent. of the Europeans of Craonne were attacked.There were on board her many A ëde8 egypti, parti-cularly gorged females, more of them being on theside of the mess-deck next the quay than on theouter side next the stream. Like Major Dive, Dr.Pirot notes the difficulty in such a climate of makingmen sleep under mosquito nets, and his opinion isthat the aedes mosquitoes should be exterminated,so that there would be no more dengue. Valuableinformation about the means of extermination ofAedes egypti will be found in a paper 3 by ColonelW. P. Chamberlain, Medical Corps, U.S. Army, thechief health officer of the Panama Canal. Discussing

1 Arch. de Méd. Navales, 1926, cxvi., 305.2 See THE LANCET, 1926, i., 453.

3 Military Surgeon, April, 1927.