6 
PROCEEDINGS OF THE ROYAL SOCIETY OF QUEENSLAND. 
Anopheles amictus is known to be capable of transmitting malaria; but 
except perhaps in the far north it is unlikely to play any great part in 
initiating or maintaining an epidemic. It is also capable of acting 
as a vector of Wuchereria bancrofti (the cause of Filariasis) and 
consequently is of potential, if not actual, medical importance. 
Control of Saltwater Species. 
The control of the saltwater species mentioned above is a very big 
and difficult problem. At a conservative estimate approximately 3,000 
square miles of breeding-grounds exist along the coast of Queensland. To 
obtain satisfactory results, breeding must be eliminated permanently; 
and the only efficient method of doing this is by a well-designed series 
of drains and ditches accompanied by levelling and filling where 
required. The cost of such an undertaking is very difficult to estimate, 
but it would certainly amount to several thousand pounds per square 
mile. Any attempt to control the saltwater mosquitoes throughout 
Queensland is quite out of the question, but in a limited number of 
small selected areas a beginning should be made. To the east of most 
of the larger coastal towns breeding areas exist, and these are responsible 
for most of the nuisance caused by the saltwater mosquitoes. It is quite 
feasible and desirable for control work to be initiated in these areas, and 
although noticeable results will not be obtained for some years, such 
work is well worthwhile. Eventually the small controlled areas would 
be linked up, and in the distant future some degree of permanent 
control may be achieved. 
On this saltwater problem, it is essential for the community to 
develop a long-range view and to be prepared to meet the expense of 
control measures, the results of which will not become apparent for 
many years. Only permanent control measures should be carried out 
and any attempt to undertake temporary control by weekly spraying 
or other such methods should not be allowed. Temporary control is 
inefficient and, in the long run, uneconomical. While on this point it is 
probably wise to comment on the publicity given to D.D.T. in the press 
recently. While D.D.T. has given excellent service under Army con- 
ditions, its use for peace-time control is definitely limited. In the 
prevention of mosquito breeding, D.D.T. can only be used as a temporary 
measure of control, and has the same disadvantages as all other 
temporary measures. 
It is hoped that the above brief summary has made it quite clear 
that there are at least three distinct mosquito problems. The most 
important is the domestic problem, because of its association with serious 
mosquito-borne diseases. Fortunately there is no reason why it should 
not be solved in a few years provided the ratepayers, local authorities 
and citizens co-operate and support a determined and sustained 
campaign. 
The freshwater problem, although big, is comparatively unimportant, 
and at present does not warrant any time or expense being devoted to it. 
The saltwater problem is a very big one and we must realise that 
its solution will not come in our time. An attempt should be made to 
start a control campaign which will bring results in the distant future. 
Unfortunately, the citizen who does not understand that there are three 
problems is discouraged by the presence of saltwater mosquitoes and 
will not give his support to the control of the domestic species, which 
affect his health and comfort to a much greater extent than the salt- 
water species. Only a long-sustained educational campaign can correct 
this state of affairs. 
