. ( 14 Rechov Ma1che1 Yisrael, 'Afridar-Ashkelon. · Israel. 28th April 1961. Dr. Albert B. Sabin, The Children's Hospital R•?search Foundation, Cincinnati, OHIO. D·aa r Dr. Sa bin, Dr. Nassry a nd I cannot tell you how grateful we are for your very p rompt replf( and advice on 9ur paper "Does Measles predispose to I'oliomyelitis • You have g iven us a lesson in the epidemiology of polio v-rhich has taught us a great deal, and it vras as if you were in theroom with us. 'I'his lesson and your encourageme nt we sha,ll always treasure a nd we h9,ve triedour best. to meet the high standards you set for the writing of a paper. 1'/e see noy.,r that it wa s a mista ke not to have sent you togethe r lv ith the first dra ft, a literal translation of our ori r.~: inal article in the "Harefuah", since v1e did t t:.ere t a ke up a nwnber..., of the points you raised in your lette r of the 15th Februa ry, although not as thoroughly as you Hould h a ve liked. I a m therefore app ending this translation now, together with our second draft for the paper itse lf, ltrhich takes account of tbe conunents in your le"4ter a nd also of the various criticisms and note s writte n in the margin of the first dra ft. In a ddit1on, we should like here to consider in greater detail, one by one, the points you h c:we r a ised in the light of a further look at our data: 1) AGE. We've analysed our data agalin as r egards age, and especially a s regards the point ive had not considered of a higher incidence of polio within the unde r 4 yea,r-olds, in those a ged 7-23 months. Vle 've found: AGE IN MONTHS: 0-11 12-23 24-35 36-47 48-60 Totals Even-Shmuel Area 3(1) 4(1) 7(2) 1 15(4) Ashkelon Region 22(4) 21(3) 10(2) 3 1 57(9) Deaths are shown in brackets. This brought out the intere sting ne1.-.r fact that 7 of the 15 cases, with 2 deaths in Even-Shmuel were in the 24-35 month age group, unlilce the tre nd for the Re gion and country as <>­ whole, which favoured the 7-23 month group. First we considered that this might be due simply to their being more childre n in Even-Shmuel in the 24-35 month age group. Dr. M:assry s a ys it ivould involve him in a treme ndous a.mount of work to detail the exa ct age in months of all the children in the area, at the time of the epidemic, but we do have records of births in Even-Shmuel by year of birth, v-rhich are similar and 1.-.rhich show:: Children in Even-Shmuel Year of Birth Nos, of childre n. 1958 (up to outbrea k of p olio) 64 1957 103 1956 98 1955 95 1954 66 Total 426 . As the children aged 24-35months at the time of the polio, will have b~en born bet1treen June 1955-Junel956, if t h eir had been Any relative increase in the nwnber in this age group, one would expect the Table to show this. /Next ; Next we considered the possibility that these 7 children had not been properly vaccinated with Salk Vacc,1ne. In tact however, 6 or them had had 3 injections' and one' 1 injection. (cr. - .Salk Vaccinations, below). Next we considered, possible better correlati'on of these 7 child­ ren -with measles: AGE IN IviONTHS: 0-11 12-23 24-35 36-47. I olio with measles 2 4 5 1 Polio without me a sles 1 2 Tota ls 3 4 7 1 3 children were from Uz a , 3 from l!, yta n and one from Sha l va, vrh ich s eems - again- a represent a tive distribution. \·Je could find no correl a tion with injections given prior to the polio, nor with previous anaem i a , nor had these 7 b ~?e n i n a poor nutr itional state on the outbrea k of the polio. Th ou~h i ntere sting, we have no explanation for this age distr ibu­ tion, a nd \:.rill welcome suggestions. 2) SALK VACC I NP... TION. 'l'he following Table det a ils t he m.m1ber of Sa lk Va ccdme Inje ctions, t be children v.r ho contracted polio, had had. Deaths in brackets. No . of Sa lk Va ccine Numbers of children with Poliomyelitis Inje ctions given Even-Shmuel Area Ashkelon Region 3 7(1) 14(1) 2 6(2) 28(4) 1 2(1) ~- .S(l) 0 0 1op~ 0-3 15(4~ 57 9 This seems to be against the c onc entration of ca ses in Even-Shmuel having been due to poorer va ccination with Salk Va ccine. One wants to know of course what the qver-all Salk Vaccina tion position was at the time of the polio in ~ en-Shmuel, and we summarise this here: Nos. of children who at the time of Settlement. the polio had !:lad 0-3 in.]ecs, of Salk 0 1 2 3 Eytan lb 63(1) b2(1) 38(3) Ahuzam 12 71 71(1) 53 Noam 11 61 59 36 Uza 16 82(1) 61(3) 59{3) Shalva 10 §.2__ 8_2 ( 1 ) Q1_{].__L Totals b5 300T2T 342Tbr 247\7T. The figures in brackets show in which groups by number of inject­ ions the polio cases occurred. The table r efers to children born 1954 through 1958 and also includes Noam. No special r elation- ship with fevrer injections is seen. The table summarises a more detailed one which is further broken down by age of birth. It seems tha t a.) vacc ination ,.,a s very similar in the various settlements a nd b) surprisingly efficient for t hose children born 1954 thDough 1957. In the case of children born 1958 a nd aged up to about 6-7 months at the time, their numbers in the various settleme nts are identical to thOse in the column tinder 0 injections. 'I'hey alone had not had the nwnber of injections laid down by r.U nistry of Health instructio-ns,beca.use of a lack of vacc ine at the time . e hasten to add that the word efficient above r efers sim ly to the number of injections given a nd not to their effectivity. We believe that techni"!:ally the giving of Salk Vaccine \vas faulty /since , < - (..f..- . ~ ~" it was first given a ll over Israel in 1956/ 7 intraderma lly, and even in 1958 only 21 cc injections were ·being given, apart from a nti­ genicity problems, but we ar e sure you will be far more informed about these technical difficulties at tha t time, than we are. How­ ever, we have assumed that these technica l shortcomings applied equally to all children given the va ccine (instructions as to tech­ nique having been changed simultaneously throughout t he country), a nd can t hink of no wa y tha t this might have selectively af fected the Even-Shmuel cases. The following data may be r elavent to t his question of the lack of effectiveness of Sal k Vaccine given before the very virulent polio outbreak. On the 17th and aga&n on the 21st October 1958, I took r bloods in all from 58 children in Uza - a.ged from 3 months to 7 years, and including 6 of the 7 who had contracted polio about 4 months · previously. Dr. Goldblum wa s interested and agreed to do their antibodies (using titre of 1/4) and these were the r e sults.: UZA- ANTIBODIES TO POLIOVIRUS=S FOUND IN 58 CHILDRE:N , OCTOBER 1958 In To T.zEe 1. T;ype 2 TlJ2e 2 16 children + + + 14 children + 0 +- 12 children + + 0 12 children + 0 0 3 childr en 0 0 0 1 child 0 0 58 children 54 28 ~ The 6 children who had contracted polio shO'tled the following: Ase in months Polio- Fell No1 of Name when bled Virus(Cause)Ill Sal k v. 1. TI(Pe 1 .58 3 -t- 0 0 1 .58 3 + 0 0 " 1 .58 3 + 0 0 " 1 ~ 58 3 + 0 + Negative 58 3 ~ 0 + II 1 .58 1 + 0 + not .54 0 ... + 0 done The l a st child was included as she too had had polio - in 1954. The absence of any antibodies found to Poliovirus Type 2 and in only half to Type 3, mus t indica te s ome t hing as to the ineffectiveness of the particular Sal k Va ccine then in use. We are also interested in knowing whether t her e is a nything in the t heory of cross-immunity. If I r emember correctly, we wer e once told t hat it wa s believed possible t hat infection with one Type of poliovirus ma y prot e~ t - though weakly - against a nother. Obviously t h is is not gener ally believed since we have instructions to give Sal k Vaccine to cases iovho have had polio as well, since they may intheory contract a s econd attack with another Type. Here, following on infection ~Ar ith a known virulent type 1 poliovirus, t here would seem to have been no effect of cross-irrillt unity on Type 2.