1. New Zealand suffered from the 1918 Pandemic of
Influenza in common with-the rest of the world.
The local manifestation consisted of a primary
wave in August and September, and a secondary
wave of great severity,which,commercing in Auckland about October 26th spread south, covering
the whole Dominion in about two weeks.
2. Meterologieal conditions predisposing to an undue
prevalence of respiratory catarrhs during the
year were an excessive rainfall and prevailing
southerly or south -westerly winds.
3. The low crude death rate, the low infantile mortality rate, the absence of overcrowding and the
healthy conditions under which most of the people
live indicate that epidemic diseases should not
obtain as favourable a soil for dissemination as
is the case in countries less favourably situated.
4. The New Zealander is less resistant to Respiratory
and Catarrhal diseases than the Britisher, and
this fact probably accounted for the undue severity of the secondary wave of the pandemic.
5. The primary wave was characterised by a morbidity
and case mortality in excess of the average for
the years immediately preceding, but it left no
impression on the minds of the people.
6. The secondary wave was characterised by excessive
morbidity and mortality and affected New Zealand
more severely than most other countries, with the
exception of South Africa.
7. The incidence and case mortality was excessively
heavy on the Native race as compared with
Europeans.
8. The influence of age and sex is seen in higher
death rates in males than in females and in both
sexes between the ages of 20 - 45 years. Similar
results have been recorded in all other countries.
9. There is no definite proof that any particular
vessel brought the secondary wave to New Zealand,
although popular opinion blames the R.M.S.
"Niagara ". Influenza was prevalent in a severe
form in the Dominion before the arrival of this
steamer, and it is probable that the arrival of
several overseas ships about this time with returning troops, each added its quota towards the
massing infection.
10. The position in Australia is interesting in that
a rigid maritime quarantine, Interstate quarantine,
and compulsory wearing of masks, and free public
vaccination seem to have delayed the advert of
the second wave and to have modified the severity
of its incidence.
11. The Administrative measures adopted to combat the
Epidemic were similar in essential details to those
adopted elsewhere. The division of the larger
cities into blocks to which one or more medical
practitioners were- attached prevented overlapping
in medical attention. The bureaux established in
the cities assisted the Medical Officers of Health
in the medical and lay organisation, and were of
great value.
12. Provision should be made for a return of the
Epidemic and the organisation set up, with improvements which experience suggested should be
kept in touch with, but there is no indication
that New Zealand will be visited by such a severe
epidemic until the next world pandemic.
13. The prophylactic use of medicated sprays is a
measure of doubtful administrative value. A drug
which has a selective action on the influenza
virus has yet to be found. The public spray
probably allays panic, and satisfies the public
that something is being done. If used, open well
ventilated rooms should be provided, and the
spray generated by compressed air. Steam jets
should be avoided as they raise the temperature
and humidity of the chamber and predispose to
chill.
Provision should also be made to
"space out" the subjects, both those waiting and
those actually in the inhalation chamber, to
avoid cross infection as far as possible.
14. Face masks are a useful means of prophylaxis for
medical attendants, nurses, and those coming into
intimate contact with patients. They should be
made of at least four and preferably six layers
of fine mesh gauze, such as butter muslin, and of
a sufficient size to cover the mouth and nose
and mould into the contours of the face. An
ample supply should be available, so that each
mask is only worn once and then placed in a convenient receptacle ready for sterilisation. The
wearing of masks by the public is a matter for
personal consideration, and may give confidence
to the excessively nervous. It is not a measure
which is likely to have any influence in staying
the spread of an epidemic.
15. Prophylactic vaccination with mixed catarrhal
vaccines)is not a measure which can be offered to
the public with any prospect of success, even
if sufficient supplies could be procured in time.
Vaccination should be attempted in the case of
troops, and in institutions or more or less
isolated communities, and in these cases is
likely to besot.* value. There seems no reason to
withhold vaccination in face of an epidemic,
although care should be taken to avoid excessive
dosage in view of a possible negative phase for
several days after the larger second dose.
16. Pathologically the fatal cases could be roughly
grouped under two heads, (1) Those in which there
was intense toxaemia with marked haemorrhagic
oedema of the lungs as chief features, catarrhal
pneumonia being present in parts but only demonstrable microscopically, and (2) Those cases in
which there was definite pneumonia, either
broncho- pneumonic or lobar in type. The haemorrhagic oedema was present in several type II
cases, but was a much less marked feature than
in type I.
17. A pneumococcus showing certain unusual cultural
features and failing to agglutinate with the
type sera of the Rockefeller Institute (type IV),
was found in considerable numbers in the haemorrhagic oedema fluid, more especially of the
earlier cases.
18. Microscopically type I cases were characterised
by a general engorgement of the vessels, haemorrhage and oedema into the alveoli. Definite
pneumonic consolidation was absent in most parts
108.
though prolonged search revealed small areas of
catarrhal pneumonia. There was intense bronchitis and frequently tracheitis. The lymph glands
showed evidence of intense toxic absorption.
In the pneumonic type (type II) , all
grades of pneumonic consolidation were met with,
from small patches of definite broncho -pneumonia
to large areas of the lobar type. The cellular
reaction in these varied considerably, in some it
was intense, in others scanty, the majority of
the cells being polymorphonuclear leucocytes.
The variety of appearances may depend on the
different microorganisms, as in those cases where
Staphylococci were found microscopic abscesses
were not infrequent. In these pneumonic cases
the haemorrhagic oedema appearance was present
in parts other than those actually pneumonic.
19. Sputum examinations were not found satisfactory
on account of the difficulty of collecting specimen6 during the earlier part of the epidemic
wave. The flora during this stage was largely
pneumococcal, but towards the close of the - epidemic this microorganism was much less prominent and the Influenza bacillus became increasingly evident.
20. Blood cultures with one exception were sterile
and did not indicate that the disease was in the
nature of a septicaemia. This seems to have
been the general experience, but in isolated
instances influenza bacilli were recovered in
blood cultures.
21. No particular microorganism seems to have been
responsible for the secondary complications
(excluding pneumonias). Influenza bacilli were
not found except in the respiratory passages
and lungs.
22. In 25 fatal cases, influenza bacilli were found
in the lungs ,arid bronchi in 20 cases, pneumococci, mostly type IV, in 19 cases, and the
Staphylococcus aureus in 17 cases. Streptococci
did not play any great part in these cases. The
pneumococci were found in profusion in the
earlier cases, but less frequently in the later
cases. The Influenza bacillus was more prominent and more readily found in the later cases.
23. In a further study of 15 strains of pneumococci,
2 from empyema fluids, 2 from lung punctures in
fatal cases not included in the 25 post mortem
cases, 1C from post mortem cases and 1 a stock
culture, it was found that 10 belonged to
group IV Rockefeller classification, 1 to
group III, 2 to group II (atypical), 1 to group I.
One culture proved to be.a Streptococcus.
24. The Bile Solubility test is useful in differentiating pneumococci from streptococci, but certain
strains are only partially soluble. This may be
the fault of the culture medium used or of the
bile salt, but there was no indication that this
was so.
25. Inulin was fermented in Hiss's serum water by all
the strains tested. The rate of coagulation of
the medium varied with different strains, some
being very active and others delayed. It was
complete in three days with all the strains
tested.
26. Opinion is divided as to whether the Influenza
bacillus or an unknown virus is the cause of
Epidemic Influenza, though the latter view is
the more generally accepted. Definite proof
that a filterable virus is the cause is still
required.
