DISEASES IN SEARCH OF

BY

C. H. STUART-HARRIS, M.D., F.R.C.P. Professor of Medicine, University of Sheffield* ft f>]/ery?ne agrees that tremendous changes have occurred in the past few years in the ?f the infectious diseases. Formidable have been both for the tt? weapons forged a c atlftent and the prevention of bacterial infections. As result, diphtheria has be- CQ^e almost extinct and the enteric diseases are much reduced, patients with strepto- 1) ^ disease and with pneumonia less often require hospital treatment, and the acute i^ness *n childhood has infections have 1?t K considerably lightened. W Wever> altered in the same way or to the same extent. Some, such as poliomyelitis, a to both children and adults. undescribed S(J ? become threat Previously conditions as myalgic encephalomyelitis or Royal Free disease, aseptic with an and little known syndromes such as , pharyngo-conjunctival a^hemOrnholm disease have achieved a of interest and even of as cjjj position importance of ,S.es of morbidity. Moreover, the development of new techniques for the cultivation has led to the realization of a method of control of certain diseases and to a H^lr.Usesk 'cia regard to diagnosis. These changes have affected the work of both clin- oUtlns and microbiologists, and yet there has also arisen a considerable divergence of iti h?0^ between these two groups of medical men. One could almost say that they live -j,,0 different worlds. virune virologist, being equipped with new techniques for the laboratory study of CoVeSes> has been more and more excited over the possibility of fundamental dis- w concerning the nature of viruses, of their mode of multiplication and of the Uity restraining their multiplication by chemical substances. Whenever he his time with human specimens he has found less difficulty in recovering vi^upiedes Sp than in classifying the agents thus recovered and in relating their presence in V^ns to the particular phase of illness or health existing in those from whom they ^rived. There has therefore arisen the phrase of "Viruses in search of disease" been to the to the Coxsackie viruses M t applied chiefly poliomyelitis-like viruses, by th? a

Virus Growth in Tissue Cultures v. intf0' Research on animal viruses has characteristically depended upon the duction of methods of each one of a cultivation, which has yielded certain haI?f ^s. knowledge but which has eventually failed to throw fresh light on existing Pr0. 0f The new look in virus research at the time stems from the introduce present ^ tissue culture methods by the Boston group of workers centring around Enders Boston children's hospital. Helped by the use of antibiotics to control contamin ^ Enders transformed tissue cultures from their previous position of technical in to a method of He was also instrumen.c0in^j ity capable exploration by any laboratory. s so that placing the tissue cultures within reach of the low power of a microscope histological observation of the changes wrought by virus multiplication cou effected. ... , tne c The two chief ways of tissue cultures for virus cultivation are preparing o method where morsels of tissue are embedded in a plasma clot and allowed to a halo of growing cells and the roller-tube technique of cells dispersed by tryp8111*^ in where the wall of the test-tube becomes covered with a sheet of cells. Virus the grC^ce cells may produce disintegration and cell-death as with or else ^ cas alter morphologically but remain alive as with the adenoviruses. In both bu changes observed microscopically are termed cytopathogenic alterations occasionally true that viruses may grow in cells without producing any visible tions. Cytopathogenic changes form the basis of methods for the titration 0 of neutralization tests for measuring specific antibodies against the viruses in or animal sera. and hu^11 studies of viruses show a great variation but animal Morphological e viruses are usually composed of small rounded particles as viewed by the e, microscope. Internal complexity of organization of these elementary bodies as action. lSSimilaf times revealed by methods such exposure of the virus to enzyme ^jcfo- internal is revealed the thin tissue-slice method of complexity by e^ect^eI yifuS graphy perfected by Councilman Morgan and his colleagues in New York. toplaS' bodies of and herpes are readily seen by this method developing *n n c^^rane' mic granular areas within complete or incomplete shells of a surrounding eeli but in the case of influenza no organized structure is found except at the Here the rounded bodies and filamentous forms can be seen escaping from juto of plasm in great numbers. The development of the virus from the moment be the cell until its release is hidden from view and cannot for some hours its m even by chemical or serological methods. It seems that the virus particletowa with the cell nucleus or and diverts metabolic activity identity cytoplasm ' replication of its own genetic material which resides in its nucleic acid conte tjfjed are the multiplication of viruses is so different from that of bacteria that we in regarding them as a distinct order of organized life, if indeed one can rega as possessing the essential attributes of living matter.

SOME COMMON INFECTIONS AND THEIR VIRUSES

Now let us turn to the diseases which either have been in search of letv^rU^ns0er us recently or which still are in search of their causative organisms. First the exanthemata?, , and herpes zoster: The Exanthemata one vvas re^ Measles virus was transmitted to monkeys some years ago but no ulltil ^ convinced that a successful method of laboratory culture had been foun yjfi1 ^g & Boston workers published their study on measles virus in tissue culture. y or fli produces an unusual cytological change?the various cells of a human DISEASES IN SEARCH OF VIRUSES 31 (fUre merge their identity into a syncytium so that large giant cells are produced. (Le ^ight in passing mention that giant cells can readily be demonstrated by swabbing or in children with measles and the cellular exudate 0 !?ares nasopharynx smearing - a for But tissue c slldes: this is useful diagnostic method measles. the culture giant e on from itifeS - permitted the development of work antibodies during convalescence ctl?n and the titration of gamma globulin against measles virus. Moreover, Enders Carried the virus in cultures of human amnion, transferred it to chick embryo (j and is approaching the development of a vaccine against the disease. A more Will line of work is the present suggestion that measles is related to dog distemper s> jj This arose from the demonstration that most children develop antibodies to ^ er)iper virus as they grow up. But the distemper virus produces such distinctive ?es in the ferret that it seems to be that this virus is related to measles ar)(j unlikely ^ore work on this theme is required. Rubella has so far defied attempts to define Ration. Chickenpox and herpes zoster virus have been grown in tissue cultures transfer from one culture to the next can be made intact ie ' only by using cells, y grafting. Grinding up the cells prevents the virus from re-entry into new cells the relation between virus and host cell must be intimate. Glandular feVe r extremely has proved much more baffling. No success has been achieved in growing the associated with mononucleosis accompanied by a positive Paul Bunnell reaction. yjej ,a cases of apparent glandular fever with a negative Paul Bunnell test have pro Toxoplasma on cultivation. This organism is not of course a virus but the tL that it can cause mononucleosis shows that glandular fever is a syndrome rather a disease. ^^tary Diseases o^t the alimentary viruses require consideration. The innocent term "D. and V." % US!y incudes many unrelated conditions. I personally agree with the suggestion 5spf>?us coliform bacteria are important causes of infantile gastro-enteritis perhaps the form as outbreaks in homes and to <}e y occurring maternity hospitals. Attempts viruses which cause gastro-enteritis have not been successful, though Q^^nstrate0ri ^ in the U.S.A. has transmitted diarrhoea with cell-free filtrates of stools to ^ ^volunteers. But none of the welter of viruses found in the stools of healthy and ? ?^ren has yet been shown clearly to bear an aetiological relation to gastro- \d ^?r ^aS v*rus hepatitis or of homologous serum jaundice been culti- Si ?Uccessfully though again the human volunteer has conclusively proved that ity exist in human specimens or excreta. Here then is a big group of aliment- ^useslseases in search of viruses.

the entero-viruses and Coxsackie j (Orphan viruses) \ Pass from consideration of the alimentary diseases to the viruses which inhabit *4 ./^entary tract, the present situation concerning the poliomyelitis-like viruses Vol?6 Coxsackie group of viruses forms another problem, this time of viruses in ?f disease. ^ j ar?e family of viruses is now known which consists of many different antigenic and which have hitherto been grouped either as "orphan" viruses or as belong- '1gtos he Coxsackie viruses.

^truses \?^eC \ ^0xsackie viruses were recovered first of all and were found by Dalldorf by Ve Method of inoculation of human specimens into suckling mice. The first strains V U^jc?vered from the stools of children ill during an outbreak of poliomyelitis in Sit ^ town of Coxsackie in the New York State. The viruses would not grow in or infect monkeys and it was hard to associate them with specific clinical Vs S* Sit ^*nce then a large number of similar viruses with the same inability to attack lce yet with pathogenic properties in baby mice has been recovered. Some, 32 PROF. C. H. STUART-HARRIS now known as Coxsackie A viruses, cause necrosis of striated muscle with resU^e. flaccid paralysis of the mice, and others (Coxsackie B) cause encephalitis in baby ^ but no muscle lesions. Twenty or more serologically different types of CoxsacK viruses and six variant B viruses have been delineated. ? at The clinical disease now accepted as being due to Coxsackie A viruses is jg A . fever of infants and children associated with herpes-like vesicles on the palate. g outD herpangina as described by Zahorsky in 1920 and it has been found as family or larger epidemics in the summer season. Yet a majority of children from jn- Coxsackie A viruses have been recovered have remained clinically well so tn fection is or subclinical. Dalldorf felt that infection mig inapparent poliovirus t ^ some way be potentiated by Coxsackie virus but could not prove this except ^ are found both viruses to be present in some faeces. The Coxsackie B viruses aS distinct. are as a cause of and logically quite They accepted 0 a cause of infantile myocarditis. In addition they have been found in faeces C.S.F. of some cases of lymphocytic meningitis. Echo Viruses It is usually difficult to cultivate the Coxsackie viruses in tissue cultures thoU&jtufes has been done with some strains. So when viruses were recovered from tissue ^ inoculated with stools and which would neither infect baby mice nor monkeys? t0 realized that yet another group of enteric viruses existed which belonged nel., any the polio nor to the Coxsackie group. As no one could associate these viruses tjje titwj clinical were termed or to them their full syndrome they "orphans" give the: ECHO (enteric, cytopathogenic, human orphan), viruses. If one were to call .fUS sackie viruses the first cousins of polio, one ought to call the ECHO strains p? second cousins. Already sixteen serologically different types are known. The Lymphocytic Meningitis Syndrome ^ Wallgren in 1924 drew attention to lymphocytic meningitis as an import^n* drome of multiple aetiology and called the non-bacterial forms "aseptic mem non-p With increased of outbreaks of many cases of tj0o. study poliomyelitis r disease have been recognized whose clinical picture conforms to Wallgren's desc ^ > a However, when an aetiological study of lymphocytic meningitis is attempts ^ been the experience of many workers that the will only accoun otjtis)> or cases. are to or pa third less of all the Some few due mumps (with without ^Ql}Se' and fewer still to lymphocytic choriomeningitis virus derived fr0*1? probably of y^pfro' mice. In Sheffield Drs. Tyrrell, Clarke and Heath have studied an outbreak rffre cytic meningitis which appears to have been due to a single species of enterovir red apy epidemic was part of a general European conflagration of which the first signs in in the Marche of 1955 province Italy. . , call"1 From the throat and also from the stools of the an Italian virolog patients ^ vjrus- Archetti readily recovered strains of a virus which he regarded as a Coxsackie jjel' then ^ The epidemic was not reported at the time. In 1956, first in East Anglia, ,g 0{ M1 gium, the Netherlands and many parts of Germany and then in the but ch" England, aseptic meningitis occurred as an epidemic, chiefly affecting now accompanied a definite rash in about one fifth of the cases. The rash isj1 . j^d by & or morbilliform eruption resembling infantum. In Sheffield, Dr- j fraP been with a modified strain of 2 in tissue culture working poliovirus type n vVn thr?at learnt the appearances of a feebly virulent strain in monkey kidney cells. eel cU^ureS' swabs and stools from this "rash disease" were inoculated into kidney JVia y gtJ.aiiis somewhat similar appearances were seen, suggesting feeble virus activity. a were identin of virus readily cultivated but for some time these could not be ^ oUf one day some baby mice were inoculated with the tissue cultures an^_?lU(jirectY?et surprise the typical appearances of a Coxsackie A virus were obtained. vjrUseS oculation of stools or throat swabs into mice failed to produce any illness. DISEASES IN SEARCH OF VIRUSES 33 next compared with others received from the East Anglian and other European H:reaks and to were to e found be serologically identical. Ultimately they proved be J*Ples of a virus hitherto called an ECHO type 9, of which the prototype strain was i3 ?Vered from the stool of a healthy child in Cincinatti. It thus seems that the ECHQ 9 ally a Coxsackie A virus and is one cause of ' lymphocytic meningitis. j leanwhile the story of aseptic meningitis has not ended with this ECHO 9 exper- e> y ECHO viruses types 4 and 6 have also caused outbreaks of aseptic meningitis. or still encounter cases from whom no viruses can be recovered either from stools is thus still a task for the future k ?r^^ie Pr?blem lymphocytic meningitis Hi 11 ^ is made worse by the multiplicity of the virus species concerned in its aetiology. tW?teroviruses t^ie Salmonellae seem perfectly adapted as human parasites and n*sh a vast and a For as has % perhaps growing challenge. just poliomyelitis epidemic disease largely because of the postponement of the initial infection from infancy to a later age, so the may cause clinical V SePoxvirus if they first encounter the child after the period of infancy has passed.

RESPIRATORY DISEASES IN SEARCH OF VIRUSES -J, number of known viruses which can cause respiratory disease is growing and . ?e proportion of the total of acute respiratory disease remains of underter- Pne aetiology. The four basic syndromes of influenza, the common cold, atypical c0J?nia and acute undifferentiated respiratory disease still furnish a reasonably Jt(w description of the clinical counterparts of the various non-bacterial respir- and \ 1 Iseases. These clinical syndromes are depicted on the left in the diagram ?Wn aetiological entities on the right {Figure 1).

SYNDROMES AND VIRUSES OF THE RESPIRATORY TRACT.

CLINICAL SYNDROMES AETIOLOGICAL ENTITIES

CROUP(l.T.B) I NaUEHZA^S. INFLUENZA b

unknown ACUTE | RESPIRATORY OISEASE febrile CATARRH4

J.H. VIRUS

_ EATOHS ATYPICAL ADENOVItUSES^^^D^f^^^ X PNEUMONIA VIRUS RICKETTSIA kumrtUQ) PSITTACOSIS-ORNfTHOSIS

FigureFigure 1i i 'Ssau AIrr is largely accounted for by infection with the two groups of influenza \ese?Za^ % and B. Influenza C has not so far occurred in epidemic fashion but appears ?ause of febrile illness. Influenza D is the name to a Ns r sporadic respiratory given \{\ l c?vered originally in Japan from cases of pneumonitis in the neonatal period. ^st year it had only been found to be associated with sporadic illness but an Ic occurred in Vladivostok in 1956 and this was apparently regarded as clinical 34 PROF. C. H. STUART-HARRIS influenza. The D virus differs a good deal from the other influenza viruses ^ecaU^jid its destructive effect on cells in tissue culture and by reason of its recovery fromjjtjes mice. Nevertheless, it produces agglutination of red cells and has other ,?S mc justifying inclusion in the group of viruses known as "myxovirus" which influenza, mumps and Newcastle disease virus of fowls.

Croup to A newly recovered haemagglutinating virus also with antigenic relationship mumps virus is that recovered from cases of acute obstructive laryngo-tra in and ve . bronchitis (Croup) 1956 simultaneously by Chanock in the U.S.A. g Toronto. Dr. Clarke is with the L.T.B. virus in Sheffield and is endeavpu ^ working vi to find out whether cases of acute respiratory disease in adults are due to this whether it is only a cause of illness in babies.

Pneumonia Atypical ^ Numerous viruses are associated with the atypical pneumonia syndrome, jjg rebu| form of the disease in which serum agglutinins develop that are active against n as of un in the cold (cold agglutinin antibody) has until recently been regarded .^g origin. Now, however, fresh evidence has been obtained by Boston workers, asso the disease with the virus recovered by Eaton during the war. One still the*eefeSpjr- r atypical pneumonia is not a numerically common form of acute disease of atory tract.

Febrile Catarrh and Adenoviruses jf ana The name "febrile catarrh" was used Drs. Andrewes, Smith t originally by a in 1938 for cases of febrile respiratory disease encountered in epidemics servicemen and particularly in recruits, which were not due to the influenza in was name a cases cjuCjjng It admitted that the covered heterogeneous collection of ^ as those some with pharyngitis and others with exudate on the tonsils as well ^ influenza-like symptomatology. No progress was made towards a solution ^ed aetiology of febrile catarrh until the recovery of the adenoviruses (originally rj^e the APC or adenoidal-pharyngeal-conjunctival viruses) in the U.S.A. in I^u;pgtoia earliest work with the adenoviruses Rowe, Huebner and others in Was gfls by or showed that certain were in the adenoids fe- serological types commonly present ^ of children from whom had been removed Later other typeS they surgically. a covered from soldiers with febrile catarrh in the U.S.A. and also from children gectcd by an acute pharyngitis. An associated in the children led to fe\)ide "pharyngo-conjunctival fever" for the children's disease but in recruits witn catarrh the eyes were frequently unaffected. An acute keratoconjunctivitis in^ ^d due to adenovirus infection has, however, been encountered both in the e. P in Britain particularly among shipyard workers. For the rest the British ^ jn has confirmed the role of the adenoviruses in outbreaks in soldiers, the R-A- . \g> \t is residential schools. Latent viruses have also been cultivated from the adlTvi^; fortunate that in spite of the of the antigenic types of the ad'en multiplicity * all of the strains develop in culture a soluble complement-fixing antigen. the ?oUfteel1 can be used for examination of human sera to uncover infection by any of 0 or more serotypes of adenoviruses now known. ? of In the experience at Sheffield even after exclusion of the cases of influe adenovirus infection, a substantial number of cases of acute respiratory aCllte remain of undetermined aetiology. Much the same can be said of en<^e0ueI-s 0 respiratory disease in the civilian population and it is now agreed by most thew?5urdeH the adenoviruses do not appear to account for a large proportion of sickness due to respiratory tract infections. DISEASES IN SEARCH OF VIRUSES 35 Common Cold . ^'hen we turn to the common cold, the aetiological situation has taken a new look the description of the virus of Mogabgab. This was first recovered by a group of Naval Medical Officers who tested throat washings from patients with various te febrile respiratory disorders in tissue culture. Another strain of this virus was ?vered in 1956 by Price from nurses of the Johns Hopkins Hospital suffering from ^nion colds. Price has recently claimed that this virus, which he calls J-H virus, a cause of 30 per cent, of the colds at a home for babies and infants, and he has ^0 0 Prepared a vaccine from the virus which has some protective effect. The M.R.C. t ^mon Cold Research Unit is testing the J-H virus in human volunteers at Salisbury. ?*?t tell you more of this work except to say that the J-H virus will grow in tissue ^eUr^s *n Britain but that it is a difficult agent to study. Even if it does account for "third of all the colds from which we suffer, we are still without any clue to the Se of common (? the remainder. Perhaps the cold is a syndrome due to several dis- sents as is the case with the other forms of acute respiratory disease. Future ^1 ^ill close this lecture by asking for patience to be exerted by those who seek to more about the many acute diseases of the respiratory tract which are still in ch L of their causative viruses. Progress though slow is nevertheless steady and so & as dj laboratory workers are not hampered by insistent demands upon their time for work, they will certainly succeed in a further clarification of the present Ure position. The almost bewildering complexity of the aetiological situation is at discouraging particularly when virus species existing in many different antigenic h are uncovered. Respiratory viruses though less diverse than the Coxsackie (L .s are nevertheless fascinating agents to cultivate and the clinician can help by % ^ Mention to outbreaks with distinctive clinical characteristics and which ar to merit intensive laboratory study.