Reprinted from THE AMERICAN JOURNAL OF HYGIENE, Vol. 45, No. 3, 305-334, May, 1947 Printed in U. S. A. TYPHUS FEVER IN ITALY, 1943-1945, AND ITS CONTROL WITH LOUSE POWDER BY F. L. SOPER, W. A. DAVIS, F. 5. MARKHAM AND L. A. RIEHL 1 (Received for publication January 3rd, 1947) A suggestion from the Office of The Surgeon General of the United States Army to the National Research Council led, in 1942, to the development of an effective pyrethrum-containing louse powder, MYL, by a United States De- partment of Agriculture group working in Orlando, Fla. Field tests of this powder in artificial louse infestations during the summer of 1942 gave such promising results (Davis and Wheeler, 1944) that similar studies on natural in- festations were planned for Mexico (Davis et al., 1944) and the Middle East. Early in 1943 it was demonstrated in Egypt by the United States of America Typhus Commission that two applica- tions of MYL powder with a 14-day in- terval between treatments would re- duce the louse infestation of an indi- vidual to a low level, and that with an adequate staff large numbers of persons could be deloused at central powder sta- tions in spite of the time consumed in removing the clothing of each individual for dusting. Furthermore, in a village where typhus was epidemic the spread of the disease ceased following the de- lousing treatment. Later in 1943, in Algeria, a technique was evolved for blowing louse powder on the inner surfaces of garments, especially those next the skin, without undressing the person treated (Soper et al., 1945). Tests of MYL and the 1 Members of the typhus team of The Rocke- feller Foundation Health Commission. then new DDT powders, carried out in the absence of typhus infection but con- trolled by louse counts before and for a considerable period after hand or me- chanical application of the powders, indicated that either should be efficacious in arresting transmission of epidemic typhus. Since a resume of the Naples epidemic with an account of the measures insti- tuted for its arrest has appeared (Wheeler, 1946), the present report will not attempt to relate the particular ac- tivity of each of the organizations which collaborated in the fight against typhus in Naples. Rather, it will describe the evolution of the epidemic and the per- sons affected thereby ; it will discuss the measures instituted for the control of the outbreak and evaluate their merits ; and it will describe in some detail the techniques and procedures recommended for applying louse powder in the event of subsequent typhus outbreaks. The typhus team of The Rockefeller Foundation Health Commission organ- ized and administered the delousing service in Naples under Col. W. H. Crichton (British), Public Health Offi-, cer, Allied Military Government (AMG) , Region III, 15th Army Group, from December 9th, 1943, to January 2nd, 1944; continued in charge of the mass delousing section of the typhus control service under Brig. Gen. Leon A. Fox and Col. Harry A. Bishop, United States of America Typhus Commission, Janu- ary 3rd to February 19th, 1944; and resumed full responsibility for all de- 305 A.J.H.. 1947, VOL. 45: PP. 305-334 306 F. L. SOPER, W. A. DAVIS, F. S. MARKHAM AND L. A. RIEHL lousing under Brig. G. S. Parkinson and Lt. Cols. W. C. Williams and Gordon Frizelle, director and deputy directors of the Public Health Sub-Commission for Italy, from February 20th, 1944, to July 31st, 1945. Administrative personnel were. drawn from both military and civilian sources including : Allied Military Government agencies ; the Municipal Health Service, Naples ; the Public Health Sub-Commis- sion of the Allied Control Commission for Italy; the Peninsular Base Section, United States Army; the North African Theater of Operations of the United States Army (NATOUSA) ; malaria control units from North Africa, Iran and Iraq ; the Royal Army Medical Corps (British) ; the United States of America Typhus Commission, the United States Navy, and the Italian Red Cross and civilian medical profes- sion. Evo~lution of the epidemic The earliest incursion of typhus in the mainland of Italy during World War II apparently occurred in late February of 1943 when a hospital train bringing soldiers from the Russian front arrived at Foggia, where 281 soldiers and officers were hospitalized. The train then proceeded to Bari, where 226 others were discharged to hospitals. On the 12th and 13th of March, 80 cases of typhus appeared among these repatri- ated soldiers. Two additional eases were reported from the crew of the hospital train, a third in the staff of the Red Cross Hospital in Foggia and another in a soldier who had gone to Messina on leave from one of the military hos- pitals. The first cases of typhus in Naples were reported in March among patients in the military hospital, one in a soldier returned by train from the Russian front and 3 ot,hers in men brought by hospital ship from North Africa. The initial case of typhus in civilians was re- ported at Aversa, some 12 miles from Naples, where the first of 8 cases, all in the same family, had its onset on April 24th. The diagnosis was confirmed sero- logically at the Cotugno San Giorgio municipal contagious disease hospital in Naples. This patient had traveled to Foggia province twice during the week preceding onset, making portions of the trip in military vehicles operating to and from the military hospital, The commandant of this hospital at Aversa claimed that there was no typhus among his patients ; however, his records of wounded and sick included several ty- phus convalescents who were brought from North Africa directly to Aversa. In July two cases were reported among patrons of a bathing establish- ment in Naples and a third case (Giu- seppe Grassi) with onset on the 16th of the month, occurred at the Poggio- reale prison, a large provincial institu- tion located in the industrial area of Naples. Grassi was released on July 21st. On the 28th he was taken to the Cotugno Hospital where a diagnosis of typhus was confirmed serologically. Poggioreale prison, the most impor- tant in the area, was surrounded by military barracks, airplane and locomo- tive works and soap and textile plants. Several direct hits during the Allied air raids of 1943 rendered some of its pavilions uninhabitable. The bathing plant was demolished, and hygiene in the prison sank accordingly. There were no shelters, and while raids were in progress the prisoners were herded together in the basement. The inmates were almost all louse infested, so that conditions for the transmission of typhus were ideal once the causal agent had been introduced. TYPHUS FEVER CONTROL IN ITALY 307 There were many opportunities for the introduction of typhus into Pog- gioreale during the winter and spring of 19421943. The disease was unusu- ally prevalent in North Africa at this time, and there are records of large numbers of prisoners, both French and Italian, who were evacuated from Tu- nisian prisons, some by way of Sicily and others directly to Naples. Dr. Sa- porito, Medical Inspector General for Italian prisons,. admitted that there was typhus among .the prisoners in Sicily 2 and that louse control there consisted of burning and replacing clothing be- cause there were neither chemicals nor equipment for delousing. Large num: bers of Yugoslav prisoners also passed through Poggioreale as late as April, 1943, and the names of some of these appear in the infirmary reports. The records at Poggioreale are re- stricted largely to the infirmary registers which escaped destruction when the riot- ing prisoners burned the personnel rec- ords in the late summer of 1943, but a number of the inmates were traced through transfer records at branch pris- ons. Following the case of Grassi, men- tioned above, Vincenzo Petriccione, who apparently contracted the disease in the prison infirmary, became ill on? July 19th. On the 23rd he went to Cbtugno Hospital, where the diagnosis of typhus was made. De Luca, a clerk in the prison, became ill with the disease on August 13th and Guerrino, one of the carabinieri, contracted it on August 2 The first outbreak wae at Milazzo, Sicily, where 37 oases with 9 deaths occurred among Libyan prisoners between January and April, 1943. Twenty c&BeB occurred among 130 Libyans at Nicosia in July, 1943, jUBt before the Allied invasion. No civilian pasea had been registered up to the prison break which came in August during the invasion, but escaping prisoners may have been responsible for scat- tering the infection in Sicily. 15th. How many other cases occurred among the prisoners and staff between this time and December, when the first cases were actually reported from the prison, is not known, but inspection of the infirmary records reveals a long list of suspicious diagnoses, and one is im- pressed by the frequency with which acutely ill prisoners were liberated or transferred to branch prisons. Typhus appeared in men transferred from Poggioreale in at least 4 branch institutions. One prisoner with a fully developed infection was transferred to Casoria on July 17th. In July and August the Poggioreale infirmary was filled to capacity so that patients -from the prisons at Gragnano, Casoria and Aversa, in whom typhus was diagnosed serologically, were refused admission. Some of these patients returned to branch prisons while others were liber- ated. The Pozzuoli prison, a reformatory for boys and mental delinquents which was evacuated in July to receive the over- flow from Poggioreale, is the most in- teresting of the 4 branch prisons where typhus occurred during the summer of 1943. Large numbers of prisoners were transferred to Pozzuoli on July 12th, 26th, and ?7th, and shortly after their arrival some 25 cases of typhus de- veloped. One patient died only 6 days after admission, and `onsets among the others began on August 5th. When the disease was finally diagnosed the prison was quarantined, and the patients were sent to Cotugno Hospital. Of no little significance is the fact that during Au- gust, when at least 25 typhus patients were present, no less than 100 prisoners were liberated, 40 or more were trans- ferred to other institutions and some 25 escaped. In the mounting confusion of August and September in Naples these potential carriers of the disease were 308 F. L. SOPER, W. A. DAVIS, F. S. MARKHAM AND L. A. RIEHL lost to sight. Many probably sought refuge in the air-raid shelters, locally called tioveros, which were as ad- mirably designed to protect runaway prisoners from the law as honest citizens from bombs. The ricovero in "Tunnel 9th of May," a main traffic artery be- tween Naples and Pozzuoli, began to yield cases of typhus in August and September. Although Naples is a city of nearly a million inhabitants it is relatively small and compact. The tenement dis- tricts about the port and industrial areas suffered extensive damage during the Allied raids in the spring and summer of 1943, so that large numbers of fami- lies were forced to reside in air-raid shelters. These were large underground chambers, most of them old quarries for tufa, the chief building material of the region. Many of the ricoveros were equipped with lights, some had water and toilet facilities and a few afforded some measure of privacy in cubicles built of wood or stone, but in general the shelters were draughty, damp and almost always dirty. Most of their permanent dwellers came from the poor- est sections of Naples. There are no official or reliable esti- mates of the usual population of the air-raid shelters in the summer of 1943, but their estimated capacity of 220,000 must have been severely taxed during the heavy raids of July, August and September. On September 23rd the Germans ordered the evacuation of a zone 300 meters deep about the port and coastal area, and some 300,000 persons were obliged to leave their dwellings on that day, which resulted in further cro.wding of the air-raid shelters. Among the evacuees were thousands who lived in the "Tunnel 9th of May." Typhus had been incubating in this shelter for weeks, and its occupants were now dispersed to the shelters beyond the 300-meter zone. With characteristic thoroughness the Germans, before leaving Naples on September 30th, opened the doors of Poggioreale and Pozzuoli prisons and emptied their infested occupants into the already overcrowded shelters of the city. Owing to the disorganization caused by the German evacuation and the Allied occupation of Naples this serious situa- tion went unchallenged. Transportation and communication facilities were in- adequate for the needs of the civilian health authorities, with the result that the investigation of reported cases, iso- lation of known cases and even the preparation of reports were all delayed. Persons affected by the epidemic The final record of cases of typhus in Naples and the vicinity from July 1st 1943, to June lst, 1944, may be classified as follows : CMWJ Deaths Civilian cases in Naples 1,403 318 Civilian cases outside Kaples 511 82 Italian military personnel 23 3 Italian civilian prisoners 37 11 Unverified civilian cases 46 15 -- 2,020 429 The unverified cases were those not hospitalized nor seen by the control service staff, and the diagnoses were not confirmed by laboratory tests. These data and the data presented in table 1 differ from those reported during the epidemic, when l&s of cases were be- ing received from various sources. Duplications have been eliminated by careful checking of the names and identifying information regarding cases reported in municipal and provincial health department lists, death certifi- cates, hospital admission records and laboratory reports, and the daily re- ports of the case-finding section. TYPHUS FEVER CONTROL IN ITALY 309 Only the 1,914 civilian cases in and outside Naples are included in the analy- sis in table 1, since soldiers and prison- ers constitute specially selected groups. Of the 1,914 patients, 91 per cent were hospitalized ; and serological con&ma- tion of diagnosis, based on Weil-Felix, Castenada or complement-fixation test, was recorded for 61 per cent. Eighteen of the patients were nurses or hospital attendants and two were physicians. TABLE Distribution of typhus cases among civilians in Naples and vicinity, by weeks, July, 1943, through May, 1944 Week ending = I = July 4 11 18 25 - On- set - 0 1 2 1 - Re- port __ 0 0 0 3 - on- set - C C C 1 Aug. 1 8 15 22 29 Sept. 5 5 3 a 12 6 8 1 19 8 4 1 26 11 7 0 act. 3 8 11 1 10 3 8 0 17 8 3 2 24 6 6 1 31 1 6 0 Nov. 7 9 5 2 14 12 5 3 21 32 12 5 28 46 26 6 Dec. 5 12 19 26 40 64 129 224 - 42 42 48 115 11 7 8 21 - Naplea - - -- l I I I , I I , , - - Rb port - 0 0 0 0 1 0 1 2 0 0 0 0 2 0 1 0 2 1 0 2 3 3 7 9 11 4 - - -- -- - Week ending Jan. 2 9 16 23 30 Feb. 6 43 75 37 32 13 33 38 35 34 20 16 38 28 37 27 9 20 26 24 Mar. 5 12 Total 19 26 on- Re- set port Apr. 2 -- 9 0 0 16 1 0 23 - I -- TABLE I-Continued - On- set - 189 137 143 117 64 10 5 1 3 4 2 0 1 0 0 0 0 0 - ,403 - 403 - RFJ- port 199 237 153 116 130 12 9 3 2 3 4 1 0 2 0 0 0 0 - ,403 - ,403 - -- - On- set - 18 23 35 57 31 - Re- port - 11 24 18 25 63 38 22 17 42 17 32 13 18 16 21 9 2 10 21 10 3 4 5 2 0 1 0 - 500 8 3 - ill - 11 3 0 3 500 _- _- - 8 3 - 511 - - I T&d 2 Re poti -- 207 210 160 261 178 171 80 107 68 72 44 75 48 34 22 51 18 35 20 24 11 6 10 22 ,903 1,903 8 8 3 3 -- ,914 1,914 Table 1. contains the distribution of these 1,914 cases, by week of onset and of report, for Naples and outlying com- munities from July 1st) 1943, through May 28th) 1944. Between July 1st) and September 26th (13 weeks), 32 cases in Naples and only 6 During the next 5 weeks the corresponding figures were 34 and 4. In the following 5 weeks (to December 5th)) 90 cases were reported in Naples and 15 outside, bringing the totals of 310 24oT 400 . 10 . : t c 0 120 - i 80 - 40 . F. L. SOPER, W. A. DAVIS, F. S. MARKHAM AND L. A. RIEHL 0 4 18 1 15 29 12 26 10 24 21 5 19 2 16 30 3 27 12 26 9 23 7 21 July bug. Sept. o-at. nav. Dao. Jan. Feb. NW. 1943 *pr. May 1944 "cl& ending FIGURE 1. Typhus casea, by date of onset, in Naples and vicinity, July, 1943, through May, 1944. reported cases to that date up to 156 for Naples and 25 outside. During this interval, however, 209 cases had their onset in Naples and 37 outside. The date of onset was that given by the patient or his family, and there was a tendency for these dates to cluster about days readily recalled; e.g., 45 cases with onset on New Year's Day. Likewise the date of report is not always epidemiologically significant, since it did not necessarily coincide with the date of hospitalization or of dusting with in- secticide. Although one or more cases occurred in Naples each week after the middle of August, the epidemic rise did not actually begin until the week ending November 7th, when there were 9 cases. It reached its peak with 224 cases in the week ending December 26th. The recession was not quite so rapid, but by March 5th, 1944, the number of cases in Naples by date of onset had dropped to 10. Figure 1 shows the gradual rise of the epidemic in November, a sharp sky- rocketing in December, followed by a reversal in the form of the curve in late December and a rapid decline in the following months. When incidence in Naples is compared with that outside the city it is apparent that both ac- celeration and deceleration of the epi- demic were more rapid in the city than outside. The median date of onset for the 1,403 cases in Naples was December 29th and that of reporting January 6th, giving an average lag of about 8 days. The distribution of families or house- holds with two or more cases is shown below : TYPHUS FEVER CONTROL IN ITALY 311 Cases in families No. of case.2 No. of families 2 130 3 49 4 42 5 28 6 16 7 9 8 8 9 6 10 2 11, 12, 16, 18,20 1 each Although louse-borne typhus is essenti- ally a contact disease, only 1,089 of the 1,914 patients came from households having more than one case. The break- ing up of families due to conditions prevailing in the city may have been partly responsible for this, but it is also probable that many cases were never reported. The application of louse powder to persons in the incubation pe- riod may also have prevented the spread of the disease within the family. The distribution of typhus cases and deaths by age and sex are contained in table 2, and in figure 2 the histograms showing the age distributions of cases among males and females are compared. The large number of persons between the ages of 10 and 24 years in each sex group is a conspicuous feature of figure 2 and may be a reflection of the break- down of the normal discipline and order of family life in this war-torn area. Young people, when homeless, probably frequented the shelters, where the risk of exposure was greatest. Thus 9 of 14 cases recorded for one of the shelters were in boys from 13 to 20 years of age. No less interesting is the greater num- ber of cases in females between the ages of 35 and 44 years. Greater exposure may have been a factor here, and since women at these ages are usually mothers with numerous children, their illness disrupts the life of the family and they TABLE 2 Age and sex distribution of typhus cases and deaths, Naples and vicinity, I%&%1944 = I - I Fend T&d 9 1 -- - e1 -- O-4 5-9 10-14 15-19 20-24 - hfsb - 40 70 124 175 94 33 73 64 134 112 236 134 309 121 215 - Md - 5 2 2 16 6 - kid 0' -- 5 3 3 13 11 rota1 - 10 5 5 29 17 25-29 57 75 132 9 6 15 30-34 55 77 132 16 13 29 35-39 50 109 159 22 19 41 4044 51 97 148 24 27 51 45-49 59 70 129 31 21 52 m-54 35 64 99 20 27 47 55-59 24 35 59 14 18 32 60-64 65-69 70-74 15 12 4 2 3 0 1 - 171 - 24 39 9 15 24 11 23 11 9 20 9 13 4 9 13 75-79 80-84 85 Unknown 2 3 0 0 - 196 2 4 2 5 1 1 0 0 _- - 204 < Loo - - Totals - Deaths - -- - are more likely to receive medical aid and to be reported. It is probable that cases of typhus were less well reported among young children in whom the disease may be mistaken for a childhood exanthema. The low frequency of cases among men of middle age may have been due partly to their employment on night shifts, which reduced their risk of exposure in the shelters, and to a large number of missed cases. Owing to the uncertainty regarding the completeness of these data, attack or fatality rates derived from them would have little significance. For practical purposes an assumption of universal susceptibility is beiieved 312 F. L. SOPER, W. A. DAVIS, F. S. MARKHAM AND L. A. RIEHL FEMALES MALES AGE FIQURE 2. Typhus eases by age and Bex, Naples and vicinity, 1943-1944. TYPHUS FEVER CONTROL IN ITALY 313 justified. The only recent account of city. Districts T, U, and W to the east typhus in Naples was that of a group were industrial areas with few habita- of 42 cases described in a bulletin of the tions, and few cases were reported from Commune of Naples in 1927, originat- them. The evolution of the epidemic ing in the winter of `1925-1926 from also varied within the districts. In area two small ships from North Africa, A, for example, half the cases occurred which entered the port without the by mid-December, while in area V this formality of quarantine inspection. Vig- stage was not reached until January orous measures appear to have sup- 8th. Areas A, C, G, M, N, P, and Q ac- pressed the spread of the disease at this counted for more than 50 per cent of time. Prior to the epidemic, murine the cases. typhus was not reported from Italy. Outside the city 511 civilian cases It is now known to be present in the were reported from 60 different com- area, but it seems unlikely that the munities of which 495 occurred within disease is sufficiently widespread to af- 25 miles of Naples (figure 4). This feet appreciably the susceptibility of limited dispersion was probably due the population as a whole. to difficulties in civilian travel as well Although exposure to infection was as to less complete reporting of cases. by no means universal, the distribution The most remote point reached was of cases shown in figure 3 indicates that Lecce and the greatest number in any typhus permeated most of the 24 alpha- one locality was 46 cases in Torre de1 betically designated districts of the Greco, a small, but busy, port at the FIGURE 3. Distribution of typhus case8 in Naples by administrative district, November lst, 1943, to April 30th, 1944. 314 F. I,. SOPER, W. A. DAVIS, F. S. MARKHAM AND IJ. A. RIEHL foot of Vesuvius. This town like many in the attack when fewer rickettsiae others is really an extension of the city are present in the blood stream, the lice of Naples. develop their infections more slowly and the risk of transmission will lessen. Epidemic potential In view of the intermediate character The question of when a typhus patient of the period of potential transmission, becomes a menace to the community is it was necessary to make an arbitrary not easy to answer. .A person harbor- assumption regarding its length, and ing a, single infected louse is not a it was decided to define this period as likely focus of disease spread during one of 18 days following onset unless in the period of survival of that particu- the meantime the patient had died, or lar louse. The individual and his own had been dusted or isolated. lice may remain well for 10 or 12 days For each case reported in Naples, or until the febrile period begins. The therefore, with onset between November febrile period may last from 16 to 18 lst, 1943, and April 30th, 1944, the days, during which time the patient's number of days (up to 18) elapsing lice may become infected and remain between onset and isolation, dusting or so until their death some 10 to 15 days death was counted. These periods of after their first infective meal. During infectiousness, when accumulated on a this period the risk of transmission of chronological basis, may be said to con- typhus organisms from the' patient to stitute the epidemic potential of typhus his associates will be greaiest. Later with respect to the uninfected popula- FIQURE 4. Distribution of typhus eases in and around Naples, July lst, 1943, to May 31st, 1944. TYPHUS FEVER CONTROL IN ITA'?Y 315 Epidemic Potential - @isolated cases) Contact Dusting . . . . . . . . . . . -. ---- lI,""".""`.""`*",L.JU 1 14 26 12 26 9 23 6 20 5 19 2 16 30 Bw. Dec. JtXlh Feb. Mar. Apr. 1943 1944 FIGURE 5. Typhus epidemie potential compared with the dusting activities, Naples, November lst, 1943, to April 30th, 1944. 100 tion of Naples. Figure 5 shows the trend of these data when plotted on a semilogarithmic scale, compared with the trends of persons treated daily by the contact and station dusting serv- ices. The dramatic evolution, progress and decline of the epidemic and the relation of the control measures to its various phases are clearly depicted here. The organization and accomplishments of delousing activities Headquarters for typhus control ac- tivities were established at the Pro- vincial Laboratory on December 14th, and delousing with insecticidal powder began on December 15th with the com- pulsory dusting of 700 passengers leav- ing Naples on the first passenger train to depart after Allied occupation. The first dusting crews were composed of nurses and inspectors from the Munic- ipal Health Department. These proved to be intelligent, faithful workers and formed the nucleus around which the greatly expanded service developed later. Subsequently, recourse was had to personnel hired through the AMG Labor Office. The delousing activities fell naturally into the following categories for ad- ministrative purposes and were initiated on the dates indicated: 1. Contact delousing (December 16th, 1943) 316 F. L. So@R, de A. DAVIS, F. S. MARKHAM AND L. A. RIEHL 2. Air-raid shelter delousing (Decem- ber 27th, 1943) 3. Mass delousing : (a) Station (De- cember 28th, 1943) ; (b) Block (February 6th, 1944) 4. Flying squadron for work outside Naples (January 8th, 1944) 5. Institutional delousing (January 9th, 1944) 6. Military and military labor delousing (December, 1943) 7. Refugee delousing (December, 1943) is the least satisfactory of the three pumps eventually used because it re- quires refilling after each two or 3 dustings, and its delivery of powder tends to be in masses rather than in clouds of dust (Soper et al., 1945). There were a few Dobbins "Super- built" no. 133 guns on hand, and later the Hudson "Admiral" no. 765 gun be- came available, both of which were found to be equally satisfactory and far superior to the "Cadet" duster (see figures 10-16). There will be no discussion of institu- .-act or spot delousing. The names tional, military or refugee delousing, and addresses of all typhus patients re- and no account of the isolation and ported after November 1st were as- treatment of the sick. Casual refer- sembled on December 12th so that the ence only will be made to vaccination homes could be visited and the contacts as a method of combating the disease. of the patients discovered and ,deloused. Insecticide and dusting equipment. An immediate result of this work was The Surgeon's Office of the Peninsular the finding of additional cases hitherto Base Section made 20,000 two-ounce tins unreported, and, subsequently, this dis- of MYL available immediately. The covery of new cases became an impor- Surgeon's Office, NATOUSA, sent 400 tant function ,of the contact-delousing pounds of DDT concentrate by air and ' squads. authorized the use of such amounts of The careful records of names and ad- MYL powder, up to 500,000 two-ounce , dresses of families dusted and new pa- tins, as were required until the Allied ' tients found, which were kept by the Control Commission stocks began to ar- squads, provided the data for group- rive in January. The relative amounts of ing the cases by families. They also MYL and DDT used in Naples cannot facilitated the preparation of block his- be accurately determined, but since most tories for certain areas, so that what of the early work was done with MYL, families had been dusted and when, in to this insecticide must go the credit relation to primary and subsequent ty- for the early resulm of the delousing phus cases, could be determined. Such campaign. information has aided materially in Hand dust-guns were used in the ap- evaluating the spot-dusting measures, plication of the powder and the work- which were those first employed. ers were trained to follow a definite In practice, all members of a patient's procedure in dusting each person, for family were dusted at the time of the which written instructions (reproduced squad's visit but absent members were below) were issued, so that the chance not sought out. The family was urged of omitting certain points might be to see that such persons attended the lessened when dusters were working nearest mass-delousing station. The under pressure. Most, of the work in squad also powdered those other per- Naples had to be done with the small sons wishing to be dusted who lived in "Cadet" type of Hudson duster, which the same or contiguous buildings. Thus TYPHUS FEVEd3 CONTROL IN ITALY 317 the term "spot dusting" more adequately describes its work. The crew usually worked in the courtyard or street in front of the building in which the pa- tient lived. On January 12th this spot delousing by persons accompanying the case-find- ing units was reduced to the immediate family and household contacm. Later in the month, however, the units re- verted to a more extensive coverage and shortly afterward collaborated with the mass-delousing service in dusting resi- dents of certain blocks in areas where typhus persisted or where surveys re- vealed an appreciable amount of louse infestation, Air-raid shelter delousing. The im- pmelter as a focus of typhus transmission was recog- nized at once, but the organization and conduct of delousing activities there presented certain problems since the work had to be done between 6 P.M. and midnight, when the shelter held its maximum population. The service was organized to care for the dusting of ap- proximately 10,060 persons weekly. Six teams, each consisting of a physician and 12 dusters, made the rounds of some 80 to 90 shelters, at first every 7 days and later once in 2 weeks, as the num- ber of cases reported from the shelters declined. factorily and adequate transportation and stocks of insecticide became avail- able, plans were ready for opening 50 public delousing stations with an esti- mated capacity of 100,000 persons daily. Sites in hospitals, schools, churches, railway and streetcar waiting rooms, etc., were chosen with consideration for population density and the known dis- tribution of typhus. Each station was under the direction of a foreman and an assistant, who were responsible for the conduct of the work and the keeping of the daily records. The first two stations opened on De- cember 28th. The one at the Ascalesi Hospital began by bringing children in from the street to be dusted. Its record jumped from 107 persons dusted the first day to 577 on the third and 1,625 persons on the seventh day. The other station at the Anguilli School had the advantage of a large pediatric dispen- sary in the same building and its clientele was sent to be dusted. This station de- loused 837 persons on the first day, 2,200 on the third and 3,585 on the seventh day. The delousing stations be- came popular overnight, so that soon the sight of persons on the street with powdered hair and clothing was too common to cause comment. The supervision of, the stations was carried out by Italian civilian inspec- tors, most of them physicians, who had a varying number of stations to visit twice daily. They issued powder and pumps, checked the work of the stations and collected the daily reports of oper- ating personnel, supplies received and used, and the number of persons pow- dered. When received at headquarters these reports were summarized each day to provide the supervisors and adminis- trators with current data on the opera- tion of every station. In a summary of the work of 33 stations operating in Naples on January 15th, 1944, there were, on the average, 13 persons working in each station, and an average of 1,611 persons were dusted per station. Some 2,500 pounds of powder were used in the 33 stations, with an average of 21 persons dusted per pound. It was only by daily checking of the activity of the stations that a proper level of efficiency could be maintained. A problem involved in the operation 318 F. L. SOPEd, W. A. DAVIS, F. S. MARKHAM AND L. A. RIEHL of the stations was the hourly variation in the volume of work to be done. Visit- ing hours at hospitals, arrival and de- parture of trains and the opening and closing of business affected attendance at the stations. The staff provided had to be sufficient to deal with persons coming to be dusted at rush hours, which meant an overstaffing in slack Mass delousing: (2) Block. As the of the stations progressed it be- came evident that a certain portion of - the population was not being reached, since typhus continued to occur in cer- tain blocks within walking distance of busy dusting stations. It was decided, therefore, to survey different sections of the city with a view to answering the following questions : (a) were per- sons living near the stations being dusted repeatedly while those at a distance were missed ; (b ) was the dusting of men, women and children of equal pro- portion ; (c) what proportion of those dusted still had lice? For this survey, groups of blocks rep- resenting different sections of a given district were chosen and detailed maps and census forms prepared. By the middle of February the canvass had covered over 100,000 persons, of whom 77 per cent claimed to have been dusted one or more times. The percentage varied from 65 around the Poggioreale prison to 93 in Fuorigrotta. Approxi- mately 20 per cent had been dusted once, 28 per cent twice and 29 per cent more frequently. Of some 13,000 children who had been powdered, 11.6 per cent were found to be louse infested, as compared with 20 per cent of 2,500 undusted children. As a result of these surveys, squads were organized on February 6th to work blocks having more than 5 per cent of louse infestation, less than 70 per cent of persons with a record of previous dusting, or both. Where typhus was being reported dusting was carried out if less than 90 per cent had been pre- viously dusted. Block dusting was be- gun when the epidemic in Naples was definitely on the decline, so that, the crews were augmented by persons re- leased from the contact-delousing sec- tion. After February 14th the residents of each block where a case was reported were dusted, as well as residents of blocks contiguous to t.he one containing the infected house. Block-dusting crews always started at the same point in each block, say the northeast corner, and proceeded to the right, calling at every door, entrance or courtyard, moving from floor to floor in the same manner, until they returned to their starting point ready to begin the next block. The squad kept a record of the dusted and undusted persons living in each household and those who were away from home were reached at school or at their place of employment. Plying squadron delousing outside Naples. The flying squadron began work on January 8th, 1944, investigat- ing typhus suspects outside Naples and operating in much the same manner as did the contact delousing squads in the city. Household and neighborhood con- tacts of infected persons were dusted, and a search was made for new cases. The squadron also vaccinated contacts as well as others in infected areas. Al- though 9'7 per cent of the cases of typhus outside Naples occurred within a 25- mile radius (figure 4), investigations had to be carried out at greater dis- tances, at times even in the zone of military operations. Some of the infected suburbs of Naples were heavily populated areas, and for these a special mobile unit was TYPHUS FEVER CONTROL IN ITALY 319 organized to carry on more extensive house-to-house delousing than could be done by the squadron. A report of de- lousing and vaccination activities per- formed by the flying squadron is given, by weeks, in table 3 with reference to the probable cases of typhus seen from January 1st through May 2&h, 1944. Approximately 630 persons were dusted per case seen. TABLE 3 Weekly block dusting and vaccination of contacts performed by the jlying squadron outside Naples, JanuamJ to May, i9& Week ending Jan. 9 16 23 30 Feb. 6 13 20 27 Mar. 5 12 19 26 Apr. 2 9 16 23 30 May 7 14 21 28 Totals = -- -- - Probable lxse* seen 1 6 17 48 F%T u 13 402 8,484 13,430 24 12,150 21 11,075 32 20,457 27 13,758 17 11,720 37 20,336 26 12,023 17 10,066 20 9,636 4 9,967 22 7,675 5 11,284 8 11,143 8 6,640 5 7,697 0 6,888 3 6,360 348 211,204 1 -- - 13 44 16 226 193 77 130 26 38 63 139 47 65 28 9 21 5 17 7 8 18 -~ 1,190 It is difficult to appraise the work of the flying squadron because of the like- lihood of reinfection from Naples, and because many persons residing in these -areas may have been dusted in the city. In 7 of the 60 places outside Naples where cases occurred no delous- ing was undertaken and in 26 places where measures were taken no subse- quent cases occurred during a 12- to 14- day post-treatment period, so the typhus potential in these communities must be regarded as minimal. Xummary of delousi?g activities. From the middle of December, when dusting operations began, until the epi- demic subsided, over 3,000,OOO applica- tions of powder were made in Naples and the surrounding towns. Table 4 contains a day-by-day report of dustings by the services in Naples between De- cember 15th, 1943, and January 15th, 1944, while the work was being organ- ized and developed. Table 5 contains the weekly report of all dustings through May 31st, 1944. From the standpoint of economy of effort and material, it is now important to decide whether con- tact or spot dusting alone is sufficient for typhus control or whether this method plus station delousing should be employed in future programs. An appraisal of typhus control by louse powder For evaluating the effect of dusting with louse powder upon the spread of typhus, the outbreak in Fuorigrotta, which was epidemiologically a part of Naples, has been chosen for considera- tion. This community, with its 11,000 inhabitants, is the area designated "M" in figure 3. Various tunnels through a narrow, high land barrier connect it with western Naples, but for the most part epidemiological factors appear to have operated locally. The eastern half of Fuorigrotta, lying west of the Naples tunnels, is characterized by narrow streets, bad sanitation and housing con- ditions like those of Naples. The west- ern half contains two municipal housing projects, one of which consists of a 320 F. L. SOP+ W. A. DAVIS, F. S. MARKHAM AND L. A. RIEHL TABLE 4 damage during the Allied air raids of Daily dusting totals, Naples, 1943 so that its two shelters did not December f&h, 1943, to January 15th, 1944 have a large resident population, but Date - c ontact usting !iCOVt?TC usting Dec. 15 700 16 435 17 576 18 1,060 19 1,387 20 1,311 21 1,569 22 1,391 23 713 24 1,345 25 26 27 28 29 944 1,765 1,131 1,404 1,767 2,042 3,078 600 600 180 30 3,683 3,386 ma 31 4,041 1,675 447 Jan. 1 2 3 4 5 6 7 E 9 10 1 , , I I 1 , , -- 5 - 2,56E 1,808 446 5,15r 3,311 492 11,495 4,231 485 19,581 2,463 1,055 22,93E 3,838 1,761 28,65E 3,344 1,041 37,96C 3,360 1,275 38,971 3,405 1,224 37,75c 1,911 1,226 66,12C 2,994 2,092 11 12 13 14 15 63,2X 3,533 2,321 66,47f 147 1,58E 60,86S 112 954 59,99E 149 1,414 53,15: 71 1,648 Totals 185,331 `9,647 !I,354 ZZZ the German air attacks in the late fall and winter caused many people to re- sort to shelters at night. Since the com- rotah bined capacity of the two shelters did not exceed 5,000 they were extremely 700 crowded during the raids. 435 The first typhus case in east Fuori- 576 grotta had its onset on December lst, ~~~~~ 1943, but was not reported until Janu- , TABLE 5 2oc 1,41c - 1,215 665 1,304 1,96f 6,762 - I :. 1,131 Dec. 19 1,404 26 2,367 3,586 Jan' 5,023 "9 16 7,569 23 6,163 30 4 822 Feb' ' 8:961 13 16,214 20 23,099 27 28,534 Mar. 5 33,043 12 42,595 19 43,600 26 41,089 72,622 Apr* ; 69,064 16 69,426 23 62,595 30 62,862 56,838 May 7 14 i73,094 21 28 29-3: 1,311 1,569 Weekly dusting totals, Naples, Decembw to 1,391 1514 1943, May 3lst, 1944 - 713 1,345 Week ending Station* Other - _- TOtd 1 29,732 15,606 45,338 24,281 11,215 35,496 , 6,403 3,206 9,609 4,550 3,367 7,917 2,307 1,762 4,069 collection of 4-family cottages, each with a garden plot, and the other of a group Totals 2,628,208 380,249 3,008,457 of large 5-story apartment buildings. * Includes mass delousing in out-of-town The town suffered relatively slight shtions, - - 4,158 4,158 8,864 8,864 18,159 20,332 38,491 197,350 30,824 228,174 408,163 27,558 435,721 334,785 19,085 353,870 188,346 29,052 217,398 174,000 24,829 198,829 165,493 18,815 184,308 147,701 16,742 164,443 144,200 20,534 164,734 139,355 20,664 160,019 130,829 18,046 148,875 102,421 20,986 123,407 83,564 11,931 95,495 80,902 13,197 94,099 66,887 8,914 75,801 61,883 16,954 78,837 64,442 7,675 72,117 52,455 5,933 58,388 TYPHUS FEVER CONTROL IN ITALY 321 ary 6th. The second case in this section occurred December 10th and was re- ported on the 18th. This patient had slept in the shelter and was the probable source of many of the subsequent cases there' and in the Via Grotta Vecchia. At the other end of the town two, cases of typhus had their onset in the munic- ipal housing developments. on Decem- ber 2nd. The people in this section used the shelter in Rione Duca d'Aosta. A criterion for determining the effec- tiveness of dusting operations must now be considered. Obviously delousing an individual during the incubation stage of typhus will not prevent infection from developing, so that cases may be expected to appear over a period of from 10 to 12 days after dusting begins, but when such persons are thoroughly dusted before onset the chances will be materially lessened that they will infect ?ecstatlon was welcomed by the people.' In the western end of the community more persons per case were dusted owing to the greater density of population, with the result that here only one case had its onset more than 15 days after spot dusting began. In the eastern sec- tion of the community where the popu- lation was more scattered and nearer to Naples the final case had its onset on January 29th, which was 6 weeks after contact dusting was started in Fuori- grotta. Because of the alarm created by the discovery of 59 cases during the first week of January, a mass-delousing sta- tion was opened on January 7th and nearly 20,000 dustings were done in the first 5 days. Beginning with Janu- ary 24th, applicants were refused dust- ing if they had been powdered during the previous 2 weeks. In the subse- .*46 per cent more than tw&e.- When the station was closed at the end of April over 58,000 dustings had been done, representing an expenditure of 1.5 tons of louse powder in addition to the cost of labor and supervision. Could the job in Fuorigrotta have been accom- plished with less money and material? -I lice and so be likely to transmit the disease to others. Hence if cases de- t.0 apear after an interval of from 12 to 15 days, the presumption is that the treatment has reduced transmission of the disease. It is also obvious that with an average. lag of from 8 to 10 days between onset and report, the effectiveness of control measures will be reduced. For maxi- mum eficiency, therefore, the dusting service must be accompanied by an ade- quate and skilled case-finding service. Figure 6 shows the individual cases' in Fuorigrotta plotted in order of onset above the horizontal line and the same cases plotted below the line when re- ported. On the 20th of December when spot dusting began in Fuorigrotta, only 18 of the 106 onsets had occurred and of these only 5 had been reported. Twelve days later, on January lst, 87 cases had had their onset with the proba- bility that none could have been pre- vented by the dusting. During the next 3 days 6 more cases occurred, but by January 5th the epidemic was virtually over although 13 cases had their onset between that date and January 29th. Figure 7 shows the rise and fall of the epldemi?@tentlal curve in Fuori- - grotta plotted to a semilogarithmic me. Between December 10th &Oth. i.e., 10 days prior and subsequent to the beginning of contact dusting, the number of undeclared cases in the area FUORIGROTTA DATE OF ONSET 7944 1 5 10 Dec;smber fgg 2.5 Jo 1 5 10 Jonyyry N) 25 Febru'qry I I I1 I I II, ,a I ! I I I1 I I I I,, , , , I I I I, I I, I IL II ! I II I, I I L I I- I ,I I f, DATE OF REPORT Fabvuory FIGURE 6. Fuorigrotta: individual typhus cases bs date of onset and report, with reference to dusting aetivitiea. TYPHUS FEVER CONTROL IN ITALY 323 rose steadily. The straight line fitted was not accelerated by the mass dusting to the logarithms of the numbers of activities begun on January 7th. cases indicates a rate of increase of A study of individual block histories 17.2 per cent daily. If the curve had in the city of Naples further strengthens continued to rise at this rate during c s on January 9th there the impression that prompt coverage another by the contact-dusting and case-finding would have been some 368 undeclared `