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Twenty-second Biennial Report . 43 nently record conditions surrounding impounded water projects before and after impounding; to work toward the future elimination as far as possible of the mosquito and malaria problem. A brief consideration of breeding habits and the effect of surroundings and changes may give something of the outlook of the undertaking. Differential Breeding The breeding habits of the different species of mosquitoes are an important consideration in the impounding of water, and is the factor that threatened to bring to grief the first water-power projects in the South. While the whole mosquito family is given with variable adaptability, each species has a marked preference for waters of particular characteristics. This is so pronounced that the type to be found in different situations can be forecast with fair accuracy. Preference with most species is for natural instead of artificial collections of water. However, when both are present this may often mean a greater extent of breeding in the natural, than in the artificial ones, rather than all breeding in one and none in the other. In all cases quiet and protection are essential for propagation. Absence of trash, weeds, grass, or other obstructions, or the presence of wave and ripple action are strong deterrents to production. Of the Anopheles, the Quadrimaculatus, or principal malaria carriers, breed in ponds, lakes, pools, lagoons and estuaries, sluggish streams and tubs and cans. Marine growth, floatage, and moderate stagnancy only add to their comfort. Organic acids such as tannic, any kind of filth as excreta or waste, or contaminations of a chemical nature tend to discourage them. Appreciable quantities of any of these will stop their breeding altogether. Anopheles Crucians tend to begin breeding where Quadrimaculatus leave off. The inclusion of minerals such as found in brackish water, or swamp and bog water containing tannic acid proves attractive to them. These attributes with a nature akin to Quadrimaculatus for peaceful water, tend to locate this group in lowlands and flat country. They therefore may be on the scene in malaria epidemics. Punctipennis is the free-water active stream group of the Anopheles. They are to be found harbored along running streams, springs, branches, and not infrequently in springs. They are more adaptable to both temperature and environment changes than the other species, upon necessity will resort to various departures from their choice of waters, and therefore, are the more widely distributed. It is hilly country with pronounced fall that affords the best impounding sites. Any kind of condition may exist on a small scale in such an area, but in whole it is one of springs and briskly moving water-courses, and therefore, the haunts of Punctipennis. Though this species can be infected with malaria it has not been proved infective in nature and disease carrying has not been generally charged to them. When such an area as they inhabit is impounded and the flowing water replaced by relatively still water, they may tend to lose interest and wane in their breeding while Quadrimaculatus thus favored will begin intensified activities which, if not controlled, soon will reach unhealthful proportions. Even though the adaptability of the Punctipennis may continue them in unabated numbers, it can be dependably relied upon that, left to their own volition, Quadrimaculatus will be added to the mosquito population evolving from such
Object Description
Rating | |
Fixed Title * | NCHH-02: Biennial Report of the North Carolina State Board of Health [1909-1972] |
Document Title | Biennial Report of the North Carolina State Board of Health [1909-1972] |
Subject Name | North Carolina. State Board of Health -- Statistics -- Periodicals. |
Subject Topical | Public health -- North Carolina -- Statistics -- Periodicals. |
Subject Topical Other | Public Health -- North Carolina. |
Description | Publication began with the 13th (1909/1910); ceased with the 44th (1970/1972) |
Creator | North Carolina. State Board of Health. |
Publisher | Raleigh : The Board, 1911- |
Repository | University of North Carolina at Chapel Hill. Health Sciences Library. |
Host | University of North Carolina at Chapel Hill |
Date | 1926-1928 |
Identifier | NCHH-02-022 |
Form General | Periodicals |
Language | English |
Rights | This item is part of the North Carolina History of Health Digital Collection. Some materials in the Collection are protected by U.S. copyright law. This item is presented by the Health Sciences Library of the University of North Carolina at Chapel Hill for research and educational purposes. It may not be republished or distributed without permission of the Health Sciences Library. |
Digital Collection | North Carolina History of Health Digital Collection |
Sponsor | The North Carolina History of Health Digital Collection is an open access publishing initiative of the Health Sciences Library of the University of North Carolina at Chapel Hill. Financial support for the initiative was provided in part by a multi-year NC ECHO (Exploring Cultural Heritage Online) digitization grant, awarded by the State Library of North Carolina, and funded through the Library Services and Technology Act (LSTA). |
Volume Number | 22 |
Health Discipline | Public Health |
Digital Format | JPEG 2000 |
Print / Download PDF Version | http://archives.hsl.unc.edu/nchh/nchh-02/nchh-02-022.pdf |
Document Sort | all; group-a; nchh-02 |
Volume Link | http://dc.lib.unc.edu/cdm/search/collection/nchh/field/identi/searchterm/NCHH-02-022 |
Title Link | http://dc.lib.unc.edu/cdm/search/collection/nchh/field/documa/searchterm/NCHH-02 |
Catalog Record link | http://search.lib.unc.edu/search?R=UNCb2375275 |
Description
Fixed Title * | Page 43 |
Document Title | Biennial Report of the North Carolina State Board of Health [1909-1972] |
Subject Name | North Carolina. State Board of Health -- Statistics -- Periodicals. |
Subject Topical | Public health -- North Carolina -- Statistics -- Periodicals. |
Subject Topical Other | Public Health -- North Carolina. |
Description | Publication began with the 13th (1909/1910); ceased with the 44th (1970/1972) |
Creator | North Carolina. State Board of Health. |
Publisher | Raleigh : The Board, 1911- |
Repository | University of North Carolina at Chapel Hill. Health Sciences Library. |
Host | University of North Carolina at Chapel Hill |
Date | 1926-1928 |
Identifier | NCHH-02-022-0047 |
Form General | Periodicals |
Page Type | all; report/review |
Language | English |
Rights | This item is part of the North Carolina History of Health Digital Collection. Some materials in the Collection are protected by U.S. copyright law. This item is presented by the Health Sciences Library of the University of North Carolina at Chapel Hill for research and educational purposes. It may not be republished or distributed without permission of the Health Sciences Library. |
Filename | biennialreportof22nort_0047.jp2 |
Digital Collection | North Carolina History of Health Digital Collection |
Sponsor | The North Carolina History of Health Digital Collection is an open access publishing initiative of the Health Sciences Library of the University of North Carolina at Chapel Hill. Financial support for the initiative was provided in part by a multi-year NC ECHO (Exploring Cultural Heritage Online) digitization grant, awarded by the State Library of North Carolina, and funded through the Library Services and Technology Act (LSTA). |
Volume Number | 22 |
Page Number | 43 |
Health Discipline | Public Health |
Full Text | Twenty-second Biennial Report . 43 nently record conditions surrounding impounded water projects before and after impounding; to work toward the future elimination as far as possible of the mosquito and malaria problem. A brief consideration of breeding habits and the effect of surroundings and changes may give something of the outlook of the undertaking. Differential Breeding The breeding habits of the different species of mosquitoes are an important consideration in the impounding of water, and is the factor that threatened to bring to grief the first water-power projects in the South. While the whole mosquito family is given with variable adaptability, each species has a marked preference for waters of particular characteristics. This is so pronounced that the type to be found in different situations can be forecast with fair accuracy. Preference with most species is for natural instead of artificial collections of water. However, when both are present this may often mean a greater extent of breeding in the natural, than in the artificial ones, rather than all breeding in one and none in the other. In all cases quiet and protection are essential for propagation. Absence of trash, weeds, grass, or other obstructions, or the presence of wave and ripple action are strong deterrents to production. Of the Anopheles, the Quadrimaculatus, or principal malaria carriers, breed in ponds, lakes, pools, lagoons and estuaries, sluggish streams and tubs and cans. Marine growth, floatage, and moderate stagnancy only add to their comfort. Organic acids such as tannic, any kind of filth as excreta or waste, or contaminations of a chemical nature tend to discourage them. Appreciable quantities of any of these will stop their breeding altogether. Anopheles Crucians tend to begin breeding where Quadrimaculatus leave off. The inclusion of minerals such as found in brackish water, or swamp and bog water containing tannic acid proves attractive to them. These attributes with a nature akin to Quadrimaculatus for peaceful water, tend to locate this group in lowlands and flat country. They therefore may be on the scene in malaria epidemics. Punctipennis is the free-water active stream group of the Anopheles. They are to be found harbored along running streams, springs, branches, and not infrequently in springs. They are more adaptable to both temperature and environment changes than the other species, upon necessity will resort to various departures from their choice of waters, and therefore, are the more widely distributed. It is hilly country with pronounced fall that affords the best impounding sites. Any kind of condition may exist on a small scale in such an area, but in whole it is one of springs and briskly moving water-courses, and therefore, the haunts of Punctipennis. Though this species can be infected with malaria it has not been proved infective in nature and disease carrying has not been generally charged to them. When such an area as they inhabit is impounded and the flowing water replaced by relatively still water, they may tend to lose interest and wane in their breeding while Quadrimaculatus thus favored will begin intensified activities which, if not controlled, soon will reach unhealthful proportions. Even though the adaptability of the Punctipennis may continue them in unabated numbers, it can be dependably relied upon that, left to their own volition, Quadrimaculatus will be added to the mosquito population evolving from such |
Digital Format | JPEG 2000 |
Print / Download PDF Version | http://archives.hsl.unc.edu/nchh/nchh-02/nchh-02-022.pdf |
Document Sort | all; group-a; nchh-02 |
Volume Link | http://dc.lib.unc.edu/cdm/search/collection/nchh/field/identi/searchterm/NCHH-02-022 |
Title Link | http://dc.lib.unc.edu/cdm/search/collection/nchh/field/documa/searchterm/NCHH-02 |
Catalog Record link | http://search.lib.unc.edu/search?R=UNCb2375275 |
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