63
immunisation had been completed. As was to be expected, however, swabs
taken from cases of pharyngitis and tonsillitis continued to be positive for C.
diphtheriæ for a considerable time after the outbreak of clinical diphtheria
had ceased. The true state of affairs was distorted, as it so commonly is in
children's schools, by the fact that large numbers of children were found with
hypertrophied and septic tonsils in which the C. diphtheriæ lurked for a long
time. The probability is that the large majority of these cases of sore throats
with swabs positive for C. diphtheriæ were cases of non-specific tonsillitis which
were merely incidentally carrying C. diphtheriæ, (i.e., so-called bacteriological
diphtheria), a state of affairs which is common in institutions after mass
,artificial immunisation has been performed.
It is interesting to note that out of 34 cases of this " bacteriological "
diphtheria five individuals carried virulent C. diphtheriæ in their noses or
throats for more than a month after all clinical signs of sore throat had dis-
-appeared, and it was only after thorough surgical toilet of the pharynx and
posterior nares that they ceased to carry.
Three of these persistent carriers were of the nasal type, their throat
swabs only rarely showing C. diphtheriæ. This illustrates the very great
importance of examining nasal swabs in all carrier examinations carried out
with a a view to controlling and tracing the source of an outbreak of diphtheria.
Cerebrospinal Fever.—Of the 30 cases investigated during 1938, positive
cultures of meningococci were obtained from 18. The majority of the remain-
ing 12 cases diagnosed by direct examination of cerebrospinal fluid occurred
in stations where laboratories were not situated. Of the 18 positive cultures
11 were Group I, 5 Group II and two were not classified.
A total of 251 cultures from cerebrospinal fluid of cases of varying nature,
including the above, were made during the year, the great majority of which
were from Northern Command laboratories (129). Cell counts totalled 295,
microscopical examination of deposits 243, Langes gold chloride test 63,
chemical examinations, e.g., globulin, chlorides, etc., 327. Two hundred and
fifty-three Wassermann tests were carried out on cerebrospinal fluid in Poona,
Rawalpindi, Quetta and Meerut.
Laboratory tests in connection with the diagnosis of syphilis.— The number
of Wassermann tests carried out in the four laboratories engaged in this work
numbered 17,177 and the number of Kahn tests 13,518. These figures in the
case of the former are 530 more than last year and in the case of the latter
show an increase of 6,647.
The percentage of haemolysed or septic sera, and broken capsules remain
much the same as. in previous years.
The employment of the Kahn test as a check or the Wassermann test as
will be seen from the above figures is yearly becoming more popular. In the
Command Laboratory, Poona and in the District Laboratory, Meerut it is car-
ried out on almost all sera received. Last year difficulty was experienced in
the District Laboratory, Quetta in carrying out this test owing to precipitation
of cholestrin in the cold. weather. This difficulty has however now been over-
come by the use of an antigen prepared by the .Difco Laboratories Detroit
which is obtained from Messrs. Baird and Tatlock, London. This Laboratory
continues the practice of bleeding guinea pigs not more than once a month.
It has been found possible to keep concentrated complement frozen for six
weeks and then still obtain a satisfactory titre of 1/50:
The work done in the four laboratories and results obtained are shown in
Tables 60 and 61.