REPORT OF THE MALARIA EXPEDITION. 
39 
While it is never possible entirely to avoid being bitten, careful persons can certainly avoid 
being bitten to a very large extent by the use of some of the measures indicated above ; and 
evidently the less one is bitten the smaller are the chances of infection. Indeed it is probable that 
the general neglect of these precautions by a community largely enhances its sick-rate. Thus in 
India the natives seldom employ either the punkahs or the mosquito-nets which are so generally 
used by the well-to-do whites ; and are certainly much more subject to fever. The poorer 
Europeans, also, frequently neglect these necessities ; and also appear to suffer more than the 
richer people. We were much struck by the fact tliat in Sierra Leone both nets and punkahs 
were seldom employed — or if nets were used, they were not used effectively ; and we have heard 
that they are similarly neglected in many other places on the West Coast. It is not at all 
unlikely that this fact will partly account for tlic fever-rate on tlie West Coast being so largely in 
excess of what it is in India. 
That this is not an exaggeration will be more readily perceived by those who possess actual 
experience of life in different tropical localities. In some, where nets and punkahs are not 
generally used, our lives at the mercy of these insects — it is impossible to steep, eat, read, or even 
in some cases to stand still, without being bitten by them. In others, such for instance as the 
large Indian cities and cantonments, where punkahs are kept going all day and nets are jealously 
used during sleep, one often lives for several days without suffering a single bite. The risk of 
being bitten — and consequently, in malarious localities, of infection — must therefore be greatly 
diminished by these precautions. Assuming that the risk is diminished to one-fourth — and this is 
scarcely too much — we may calculate that the fever-rate will be correspondingly reduced by 
three-quarters. Prophylactic measures which promise anytln'ng like so much are certainly not to 
be despised. 
Nets and punkahs, then, should always be employed in malarious countries by persons who 
can afford them. 
Screens of wire-gauze to the windows seem to be especially indicated in public buildings 
such as barracks, hospitals, jails, and asylums. In such buildings there are usually large wards in 
which a number of persons sleep together. Here — as for instance in the Wilberforce barracks 
\_paragraphs 7, &] — the Anopheles^ if they are present, simply carry the infection uncontrolled from 
one to the other of the inmates, until finally a large number become infected. Screens would 
limit both the ingress of the insects, and also their egress for the purpose of laying their eggs. 
Thus few insects would gain admission, while those that do would probably soon perish 
{^paragraph 
Lastly, medical men must always remember that patients witli gametoc)'tes in their blood 
are infective where Anopheles exist, and must be jealously "protected from bites in tiie interests of 
other occupants of the same or neighbouring houses. 
It will be observed, however, that precautions against the bites of gnats, while feasible to 
intelligent and well-to-do persons, are scarcely likely to be employed by the mass of the population, 
at least in malarious areas outside Europe and America. Other measures are required for 
the prevention of gnat-fever on a large scale. 
