14
REPORT OF THE KING INSTITUTE , GUINDY
( b) Vaccination methods.—An inquiry is undertaken on the utility of the
multiple pressure method of vaccination. This method which is chiefly in vogue
-in the United States of America is advocated on the following grounds :
—
( 1 )
T h e p r o c e s s i s l e s s p a i n f u l t o t h e c h i l d .
( 2 ) T h e r e a r e f e w e r c o m p l i c a t i o n s .
(3) The reaction of immunity is found to develop better with this than with
any other method.
The investigation is being carried out in the Saidapet range, which is under
the Institute's control. The results obtained so far seem to show that the method
is undoubtedly of great value in revaccination. Further trials in primary and.
secondary vaccinations are being made. A report will be published in due course.
4. Water bacteriology— (a) Classification of lactose fermenters.—Dr. T. Sita-
pati Ayyar continued his researches on the classification of lactose fermenters
by serological methods. He found that—
(1) Three types of lactose fermenters could be differentiated by specific
coli serum—human, bovine and soil.
(2) Each type of lactose fermenters is normally present in very high
proportion in the particular pabulam described by its name.
The applicability of this classification in judging the potability of water is
n OW being investigated.
( b) Observations on the water of Red Hills Lake. —Mr. T. N. S. Raghavachari,
along with the Corporation Analyst, continued his studies on the Red Hills Lake
water. A paper describing the results obtained has appeared in the Indian
Journal of Medical Research, Vol. XVI, 1929.
Both the authors are now engaged on a systematic study of atypical vibrios
isolated from Red Bills Lake water from time to time, which seem to resist chlori-
nation and appear in the mains after filtration.
5. Clinical bacteriology.—( a ) Difficulty is often experienced in assigning a
definite pathogenic role to any of the number of organisms isolated from patholo
-gical materials particularly in sub-acute and chronic infections. To facilitate
this Solis-cohen and Cronine Lewe have introduced a technique which they call
"Pathogen-selective culture method." The technique is as follows :—
"By this method. an equal quantity of any specimen to be examined is
inoculated, so far as possible simultaneously, on to suitable media on the one
hand, from which after incubation, will be obtained the ordinary direct or "A"
cultures, and on the other hand into 5 c.m. of the patient's own blood (freshly
drawn), which, after incubation and subsequent sub-culture on to similar media,
will provide the pathogen-selective or "B" cultures, according to whether the
patient's blood happens to be able to inhibit, or otherwise, any or all of the
bacteria shown by the "A" cultures to have been present in the specimen."
This technique is being adopted by Dr. T. Sithapati Ayyar in selecting
strains for the preparation of auto-vaccine, etc. The results are encouraging and
will be reported shortly.
( b) Investigation of an outbreak of Paratyphoid A.—Sub-Assistant Surgeon
K. S. Ranganathan investigated an outbreak of enteric fever which occurred in a
girls' school hostel at Cocanada. This proved to be due to Paratyphoid A
infection. Serological observations were made throughout the course of the
infection. It was found that—
(1) Primary agglutinins for B. Paratyphosus A do not develop to a high
degree until late in the disease, sometimes not until convalescence.
(2) Their curves may not rise as high as those for B. Typhosus.
(3) Agglutination titre of the specific organisms is not always neces
-sarily higher than the titre obtained with group organisms.
( c) The Institute staff co-operated with Lt.-Col. Wright in the bacteriolo-
gical investigation of an epidemic of superficial punctate keratitis. It was found
that the disease was due to a filtrable virus.