Page 263 - Bahrain Gov annual reports(V)_Neat

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Malaria in Bahrain is gradually dying out and the disease will soon no longer be endemic.
It is doubtful if it will ever be possible to achieve its complete eradication as the number of
breeding places arc numerous and continually on the increase. The absence of a drainage and
sewage system is responsible for most of the breeding in the urban areas and neglected irrigation
systems in the gardens. To keep this breeding potential under control, it required the strictest
supervision by the Anti-Malaria stall’and the use of about 50,000 gallons of Larvicidal oil which
was nearly double the quantity used last year. This effort resulted in a large reduction in the
amount of breeding in the rural areas but was less successful in dealing with the more difficult
task in the towns. The figures for the past two years arc:—
1954 1955
Manama 1,753 2,184
Muharraq 308 1,048
Rural Areas .. 31,160 1,844
Total .. 33,221 5,076

TifTa fogging and residual spraying were employed for the control of adult mosquitoes.
The first method is popular with the public but its value as an Anti-Malaria measure is limited
and it was used chiefly for the destruction of flies. On the other hand residual spraying of
living quarters was both popular and highly effective and was carried out before the start of
each transmission period with a Gammexane Lindane preparation. There arc as yet no signs
of resistance by local insects to this insecticide.
The Entemological study of the local malaria vector was continued during the year.
Mosquito collections were made in their natural habitat in both the larval and adult stages and
identified in the laboratory. The results were as follows:—
Number of
Examinations Stephensi Pulchcrrimus Fluviatlis Supcrpictus Sergenti Hyreanus

Larve .. 3863 3276 473 101 10 2 1
Adults. . 1884 1585 244 28

A Meteorological Station was opened in Manama in February and statistics will now be
available for the study of the associated conditions of temperature and humidity favourable
to the longevity and matabolic activity of the malaria vector and to correlate meteorological
conditions with epidemiological trends.
The maximum and minimum readings recorded each month in respect of the temperature
and relative humidity together with the rainfall for the period as under, were:—

Temperature Relative Humidity Rainfall
1955
Max. Min. Max. Min. Inches
February 76° 54° 97% 40%
March 78° 58° 100% 42% 2.06
April 90° 62° 100% 53%
May .. 92° 70° 100% 57% .35
June 102° 82° 100% 15%
July .. 104 84° 100% 20%
August 104° 83° 100% 19%
September 101° 81° 100% 17%
October 90° I 70° 100% 17%
November 86° 68° 100% 28%
December 82° 60° 100% 38% 2.47
4.88