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Hong Kong Annual Administration Reports, 1841-1941
COLONIAL REPORTS-MISCELLANEOUS.
By special request there had been no selection of specimens, all those caught on the various dates named being sent for examination and classification; so that during the period between 4th September and the date of our visit 40 per cent. may be taken as the actual average prevalence of the Anopheles among all mosquitoes found. The species is a larger one than that most common in Hongkong, and we identify it as Anopheles Sinensis.
4. From police records placed at our disposal we ascertained that the cases of Fever among the police during the last twelve months have been as follows:
Month Number of Cases Strength of Force November, 1899 2 Europeans, 7 Indians December, 1 January, 1900 February, *** March, " April, # May, June, " July, ** August, " September: " October, 4 3 Europeans, 22 Indians November, **It is noteworthy, on comparison of this with the preceding table, that while the enumeration of Anopheles rises to 60 per cent. of all mosquitoes found at the date of our arrival at Táipó, Malarial Fever had almost disappeared. We attribute this rapid fall in the number of cases of fever during the period of the cutting of the second rice-crop, which we found in progress, and during which the previous experience of the police would have led to the expectation of an increased number of cases of Malaria, chiefly to the recent adoption of vigorous prophylactic medication with quinine on two days successively at intervals of seven days.
5. We made careful search in all directions around the Government buildings and matsheds for breeding-places of Anopheles, our investigation extending over the adjoining paddy-fields as far as the river to the north, to the villages on the west, and across the river and up certain of the ravines beyond it on the south side.
We show the results of our search on the accompanying rough sketch-map, the places where Anopheles larvæ were found being indicated with red ink. We believe that the negative results in the paddy-fields and in the whole river valley to the south were probably chiefly due to the washing away of larvae by the rain-storm which accompanied the typhoon three days before our visit. The positions in which larvæ were actually found abundantly were in the narrow ditches around the uppermost paddy-
* Not re-printed.