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The data upon which this paper is based are the results of an investigation of the limnological role of bog mats in mosquito production. One of the characteristic features of bog lakes in the Great Lakes region is the occurrence of marginal mats which vary in kind and differ in extent through all degrees from small fringes to large conspicuous areas many acres in size. In their totality these mats in Northern Michigan cover many square miles. Since such mats overgrow the surface of the open water of bog lakes, they impound, both within and upon themselves, great quantities of water in such a way as to appear to provide unusually favorable conditions for mosquito breeding. However, popular opinion is conflicting on this point, some contending that they must be great breeding grounds and others insisting that mosquito larvae do not occur in these mats. Thus far, the writer has not found in the tremendous literature dealing with mosquitoes any paper which treats specifically with this problem. In this investigation the writer has attempted to evaluate certain kinds of bog mats as mosquito breeding grounds and to determine the linnological features of these areas in relation to mosquito life. This study was begun in the summer of 1935 and continued throughout each succeeding spring and summer through 1939. Intensive field work was carried on during the spring and early summer since these periods were soon discovered to be particularly significant. The writer is indebted to Professor Paul S. Welch under whose direction the work was done; to Professor Robert

Summary Twenty-six cities, towns and villages located in various parts of the northern half of Venezuela were visited and inspections made to determine the extent to which the breeding of the yellow fever mosquito, Aedes aegypti, was occurring. Observations were also made at each place on the system of water supply and on other conditions having potential influence on the breeding and distribution of this species. In practically all the places visited, the system of water supply was found to be of such a nature as to necessitate the use of numerous containers for water storage in the houses, thus providing conditions favorable for breeding of domestic mosquitoes in the habitations. Fifteen of the cities and towns had a piped water supply—at least the better class houses had this convenience—but in only one town, San Cristobal, was the supply sufficient to provide running water in the houses at all hours of the day and night. The other 11 towns and villages depended for their supply on stored rain water, wells, and nearby rivers. In 14 of the places visited, water was observed being sold in the streets by venders. In the 26 places visited, more than 3506 houses were inspected and 10,229 water containers were examined. No Aedes aegypti breeding was found in 3 of the towns, Calabozo, Ortiz and San Cristobal. The other 23 places were all positive. In these 23 positive towns the house visits totaled 3255 and breeding was found in 1550, giving an average house percentage of 47.61. The water containers examined in the 23 towns numbered 9616 and consisted of the following vessels: 2725 tinajas, 2053 ollas, 1822 barrels, 1083 pilas, 824 filter stones, 288 tanks, 23 ornamental fountains, and 798 miscellaneous containers. Of these vessels, mosquito breeding was found in 2752, or 28.61 per cent. The positive containers included 1020 tinajas, 990 barrels, 278 ollas, 232 pilas, 95 filter stones, 70 tanks, 5 ornamental fountains, and 62 miscellaneous vessels.

IV. Summary Malaria is a disease of great, although not of paramount, importance in the Philippine Islands. It is found chiefly in foothill regions, being transmitted principally by the funestus-minimus sub-group of mosquitoes, which tends to breed in small rivers or streams, or flowing ditches of clear, somewhat shaded, fresh water. There are seasonal variations due either to the drying up of streams or to such an increase in velocity or volume as to make mosquito breeding impossible. Hence, very wet or very dry seasons are not malarious. Flat lands and all areas above 2000 feet in altitude are not malarious. The low coastal plain is not malarious. In general, malaria in the Philippines is a disease of transitional seasons and transitional regions. As in all tropical regions, malaria control in the Philippines presents a serious economic problem. Probably not more than G$0.05 per capita per annum could be spent in the average small malarious community for control measures. Such measures will have to be continuous for this century and perhaps for the next. The tropics generally are poor in money but rich in time. Malaria control must be planned with this fact in mind and all available, feasible measures utilized. Anti-larval measures can not be omitted from any control program. Such measures, added to bed-nets and anti-malarial drugs should bring about results in time, provided a modest educational campaign and continued research is coincident with them. But in the Tropics no more permanence may be anticipated in malaria control than in road repairs or water-sterilization.

Summary During the mosquito breeding seasons of 1921, 1922, and 1924 a total of 904.9 square yards of water surface in selected Anopheles breeding areas was covered by nets and 585 adult Anopheles, emerged therein, making an average daily emergence of 0.653 per square yard. The nets were located in areas which showed a higher larval rate, as determined by larval counts, than is generally found in the Anopheles breeding areas of the region. An increase in the number of larvae present in the selected areas did not cause a proportionate increase in the rate of emergence. This may have been caused by a scarcity of suitable food in the concentrated areas, or by the activities of certain enemies of the larvae. The females of Anopheles were found to emerge in somewhat greater numbers than the males. A discussion is given showing that this condition is usually met with among Anopheles although approximately equal numbers of the sexes have been observed at certain times, and at others, a large preponderance of males has been recorded.

Summary The present paper reports a series of observations on the habits of the adult mosquitoes dwelling in the llanos, the grass land of Eastern Colombia. The observations summarized here were made during the rainy season, in the months of June, July and November, 1948 and June, 1949. Captures of adult mosquitoes were made by means of stable traps and with muslin tents covering an area of 4 sq. m. of ground. Catches of flying mosquitoes were also made using nets of strong muslin, fixed to a moving vehicle. The tent captures were made in series along a straight line stretching from a breeding place to the middle of an expanse of savanna. They were all made during daytime, between 7 A.M. and 5 P.M. The grass under the tent was sprayed with citronella in order to disturb the resting mosquitoes, which were then easily caught on the sides and cover of the tent. Each trial took between 15 and 20 minutes time. In a total of 104 captures, an average mosquito density of 11.9 mosquitoes per trial was obtained. Culicines formed the bulk of these captures. The average anopheline density was 1.2 mosquitoes per trial. As the type of tent used covers 4 sq. m. of ground, this means a density of roughly 3 million mosquitoes per sq. km. and 300,000 anophelines per sq. km. Males and females of A. peryassui, A. pessoai and A. parvus were found resting in the grass. A male of A. punctimacula was also found in these captures. The commonest culicine species were Culex chrysonotum, Culex (Melanoconion) sp. and Psorophora confinnis. Direct observation showed that usually the mosquitoes were resting in the grass at no more than 10 cm. above the ground. A total of 570 male culicines and 536 females were caught in the 104 trials, which may be taken as an indication of a similar span of life among both sexes. Total number of anophelines was 30 males and 98 females, perhaps too small a sample to draw any definite conclusions as regards survival. The average fertilization rate among both groups was 81 per cent, which indicates that mating occurs in all probability shortly after the emergence of the adults. In the course of these studies it was noticed that usually a mosquito breeding place can be found anywhere in the llanos at no more that 1,000 to 1,500 m. distance. The maximum distance recorded from a breeding place was 1,800 m. Female mosquito density proved to be nearly uniform across the savannas, but male mosquito density was found to be higher near the breeding places than far away from them. Such findings demonstrate that, at least during the rainy season, any part of the savannas of the llanos is within the effective flight range of the species living there. A series of parallel stable trap captures made in the vicinity of a breeding area and at a distance of 1 km. gave a mosquito density approximately the same for both locations. Stable trap captures yielded a good number of anophelines but they gave inadequate information as regards the culicines. Tent captures and captures from a moving vehicle, are considered superior to the ordinary way of trapping to obtain direct information on the real mosquito density and on the composition of the mosquito fauna in a savanna country. Biting activity of mosquitoes was measured over a 24 hour cycle by periodical removal of the mosquitoes entering a baited stable trap. Maximum activity took place shortly after sunset, continued during the night and had a slight increase before sunrise. Mosquito activity during the day was practically nil. Direct observations were made of sexual activities. Swarms of culicines were seen over the savannas as early as 5 P.M., but mating of anophelines was only observed on two occasions at 7 P.M.; swarming males captured then proved to be A. peryassui.

In this work, we analyze a system of nonlinear difference equations describing community intervention in mosquito control. More specifically, we extend the model given in [M. Predescu, R. Levins, T. Awerbuch, Analysis of a nonlinear system for community intervention in mosquito control, Discrete Contin. Dyn. Syst. Ser. B 6 (3) (2006) 605–622] to allow for consciousness to be created in an ongoing way by educational efforts that are independent of the presence of mosquito breeding sites. In order to quantify the effect of random external events, such as weather or public concerns, we consider a stochastic version of the model. Numerical simulations show that the stochastic model is consistent with the deterministic one.

Summary: Background: Dengue fever (DF) is a vector-borne virus transmitted to humans by infected Aedes mosquitoes. In this study, we identified the most important factors associated with the prevalence of IgG antibodies in a border state between Sudan and the new republic of South Sudan. Objectives: To quantify the association of specific factors with the prevalence of DF IgG antibodies in Lagawa among subjects aged 16–60 years in 2012. Methodology: Analytical cross-sectional community-based study conducted in Lagawa in 2012. Results: Indoor mosquito breeding was the most significant predictor affecting DF IgG serology. Household water storage was also strongly associated with the presence of IgG antibodies. Residence in urban areas, younger age and a history of travel to the Red Sea State were significant predictors of DF IgG seroprevalence in South Kordofan state. Conclusion: Indoor (household) behaviors associated with DF infection should be modified to mitigate the infection risk in the study area. Awareness should be raised regarding DF in Lagawa to ensure community participation in all control measures, and the surveillance system at the border between Sudan and the republic of South Sudan should be strengthened. Keywords: Dengue associated factors, Dengue Sudan, South Kordofan, Prevalence ratio

Dengue fever is an infectious vector-borne disease in Malaysia. Descriptive spatial analysis indicated the DF infection was normally distributed in urban area. As for the environmental attributes, there was no significant difference except for the existence of abandoned houses across the study area. As for breeding index, it was found to be high in all temporal indices in the locality. However, it was noteworthy that there was a significant difference in the preferred breeding containers in all temporal risk indices. As a conclusion, the risk factors for Aedes mosquito breeding sites should be considered in carrying an effective vector control. © 2013 Published by Elsevier Ltd. Selection and peer-review under responsibility of the Centre for EnvironmentBehaviour Studies (cE-Bs), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia.

The mosquito breeding area of Lake Apastepeque, El Salvador, was treated 11 times over a 7-week period with Romanomermis culicivorax to control Anopheles albimanus and An. p. pseudopunctipennis. Parasitism averaged 58% but varied greatly from treatment to treatment and from site to site. However, three applications made during evening hours to avoid wind and wave action on the lake produced an average 86% parasitism. No significant differences in susceptibility to R. culicivorax were found between instars or between species. Also, no correlation was found between nematode dosage rates and levels of parasitism. Though the parasitism averaged about 60% of the desired level, Anopheles populations dropped from more than 10 per dip at the beginning of the release program to 0.6 per dip at the end of the release period (a 94% reduction). This is the first successful attempt to control mosquitoes on a large scale by using a parasite or pathogen.

To provide a conceptual basis applicable to future antimalarial efforts, we sought to identify the sources of success in three notable campaigns that were consummated largely before DDT became available. A variety of measures directed against the aquatic stages of the anopheline vectors provided the main strategy for the antimalarial programs in Palestine/Israel, Italy, and the Tennessee River Valley of the United States. Source reduction-the modification or elimination of aquatic habitats to reduce mosquito breeding -was applied extensively and proved decisive. In all three regions, transmission of malaria was reduced to the point of extinction. Effective measures against anopheline larvae, in particular through source reduction, depend upon locally derived ecologic concepts that can be adapted to each vector species and applied continuously without limit of time. An integrated control program based on the long-term application of such measures can suppress transmission of malaria in edemic areas, as well as contain episodes of locally increased transmission of malaria.

The Grove Creek basin includes an area of about 42 square miles in Duplin County, southeastern North Carolina. The North Carolina Department of Human Resources (DHR) proposes to implement a channel restoration project on about an eight-mile reach of Grove Creek. The purpose of the restoration program is to improve drainage, thereby reducing frequency and duration of overbank flooding and reducing the opportunity for mosquito breeding in frequently flooded areas adjacent to Grove Creek. This study evaluates the effects of the restoration on the frequency and duration of flooding within the study reach for present (1984) and proposed restored channel conditions. The proposed restored channel is estimated to increase the carrying capacity of the main channel from 10 to 19 times. The greatest reduction in areas of flooded land immediately adjacent to the study reach would be west of North Carolina Highway 11 (between sites 4 and 6) and would be reduced by an average of 29 percent during floods up through the 10-year flood level and reduced by an average of 5 percent for the 25to 100-year flood levels. An average reduction of 1 percent is indicated for areas inundated east of North Carolina Highway 11 (for sites 1 through 3) for the 2-, 5-, 10-, 25-, 50-, and 100-year floods; while reductions in inundated area of the total study reach of 13, 5, 4, and 1.5 percent are indicated for the 2-, 5-, 10-, and 100-year floods, respectively. Overbank flooding during 1983 and 1984 water years occurred 32 times and persisted from a few hours up to about 3 months. For proposed restoredchannel conditions, overbank flooding would have been reduced to 5 occurrences, and area! flooding would have persisted from a few hours to about 2 days. Flooding on the Northeast Cape Fear River causes variable backwater conditions on the lower Grove Creek study reach. A 100-year flood on the Northeast Cape Fear River would create backwater for about 1.5 miles upstream on Grove Creek.

in other areas where malaria persists, there is a continuing need for control measures. The presently available methods include physical and chemical control of mosquito breeding, spraying of houses with residual insecticides for killing of fed mosquitoes, and antimalarial treatment of infected patients. Physical and chemical methods of controlling the breeding sites are effective when breeding is in a localized area accessible to control measures. One of the most ingenious approaches was applied in Trinidad, where the vector, Anopheles bellator, bred in water trapped in bromeliads epiphytic on trees. Spraying of the bromeliad with copper sulfate made breeding of mosquitoes impossible and eliminated the mosquito and malaria from the island. The fact that economically feasible methods for control of breeding sites are usually not available has led to increased interest in biological control of mosquitoes. One such approach, release of sterile males, eliminated Anopheles albimanus from a small lake in El Salvador [1]. Release of sterile males in less localized areas, however, presents serious logistic problems. Moreover, because of

Egypt is currently witnessing a number of mega projects, along the axis of Suez Canal, which consequently have a great effect on environment and its biological components including mosquito vectors of diseases. This study is an attempt to explore the use and efficiency of integrated remote sensing-GIS techniques and field surveys for detection of mosquito breeding habitats at Suez Canal Zone. Remote sensing and field surveys provided the necessary verified ground truth information to the present study. A corrected Landsat8 image, acquired in Jan. 2015, was utilized to produce NDVI, NDMI and LST to identify environmental variables associated with mosquitoes breeding habitats. Concurrently, a GIS model was developed to predict probable mosquito habitats and areas under environmental risk of diseases transmission. Results revealed that Culex pipiens and Ochlerotatus detritus are the most abundant species in Suez Canal Zone recording total number of 362 larvae (51.86%) and 244 larvae (34.96%), respectively. The model predicted that Ismailia is the most subjected Suez Canal Governorate to mosquito borne diseases. It recorded the maximum levels of high risk, risk and vulnerable areas to mosquito proliferation; 6.06 km 2 (64.26%), 954.65 km 2 (54.58%) and 152.87 km 2 (80.09%), respectively. The developed prediction model achieved an accuracy of 80.95% and increased to 100% at sites where predicted larval habitats were ascertained by in-situ checks.

The World Health Organization (WHO) has stated that effective vector control measures are critical to achieving and sustaining reduction of vector-borne infectious disease incidence. Unmanned aerial vehicles (UAVs), popularly known as drones, can be an important technological tool for health surveillance teams to locate and eliminate mosquito breeding sites in areas where vector-borne diseases such as dengue, zika, chikungunya or malaria are endemic, since they allow the acquisition of aerial images with high spatial and temporal resolution. Currently, though, such images are often analyzed through manual processes that are excessively time-consuming when implementing vector control interventions. In this work we propose computational approaches for the automatic identification of objects and scenarios suspected of being potential mosquito breeding sites from aerial images acquired by drones. These approaches were developed using convolutional neural networks (CNN) and Bag of Visual Words combined with the Support Vector Machine classifier (BoVW + SVM), and their performances were evaluated in terms of mean Average Precision - mAP-50. In the detection of objects using a CNN YOLOv3 model the rate of 0.9651 was obtained for the mAP-50. In the detection of scenarios, in which the performances of BoVW+SVM and a CNN YOLOv3 were compared, the respective rates of 0.6453 and 0.9028 were obtained. These findings indicate that the proposed CNN-based approaches can be used to identify potential mosquito breeding sites from images acquired by UAVs, providing substantial improvements in vector control programs aiming the reduction of mosquito-breeding sources in the environment.

Surface agents to smother mosquito breeding sites have been used extensively for mosquito larval control. Such agents range from oil films and chemical monolayers, to expanded polystyrene beads(1,2). Here, Lu Bao-lin discusses the use of Azolla - a floating fern - for a similar effect. The fern has the additional advantage of providing a useful source of green manure as a crop fertilizer.

This beautiful volume is a monument to the author, who, for so many years, has been one of the great authorities upon malaria in India, and through whose efforts so much has been accomplished in that country in the prophylaxis of malarial infections. While the work is entitled “Malaria in India,” thus giving the impression that it is devoted entirely to a discussion of the occurrence of malarial infection in that country, it is really a complete monograph upon the malarial fevers and one of the best that the reviewer has read. While throughout the work, especially in the chapters treating of economic problems, mosquito breeding, and prophylaxis, the subjects are considered with special application to India, it will be found that what is written can be just as well applied to other regions, and one is impressed with the practical knowledge of the author and his common-sense view of the problems that are considered.

Part I (10 pages) of this book considers protection against bites of mosquitoes. It deals with such subjects as nets, repellents, screening, etc. Part II (20 pages) is devoted to measures directed against adult mosquitoes under the following headings: destruction by hand, traps, fumigation, sprays, cutting down of jungle and other vegetation, cultivation of alleged deterrent trees and plants, the use of bats as mosquito-destroyers and zooprophylaxis. Part III (63 pages) takes up measures directed against the larvae of mosquitoes under the following topics: clearing of jungle or scrub, drainage, oiling, chemical larvicides, copper sulphate, vegetable larvicides, larvicidal fish, introduction of deterrent aquatic plants, biological control of mosquito breeding and methods advocated in certain special circumstances. The wealth of detailed information found in such a small book is surprising and all workers interested in the destruction of Anopheline mosquitoes will find this book useful, especially those individuals who do not have access to a good library.

To the Editor: —Referring to the book review on this subject inThe Journal, May 14, it seems to me that the criticism published therein is quite inconsistent with the fact that we have received second highest honorable mention in the health contest for cities with a population of between 400,000 and 500,000. I note the article states that under food control is grouped the control of rabies, which is not true, and it also states that cutting weeds is not a matter of sanitation. We regard it as such for the reason that vacant lots grown up with weeds which decay and furnish a place for dumping of insanitary matter result usually in an insanitary condition unless kept free of weeds. It is also a menace to the health of the residents in the vicinity of such places on account of hay fever and asthma, mosquito breeding, and so

The author, during the course of pond studies in connection with mosquito breeding, has had the opportunity of observing in some detail a type of pond which seems to be characteristic of at least a part of the Georgia coastal plain. Ponds of this type show remarkable similarities not only in the vegetation but also in the physical and chemical properties of the waters and the substrata. It was decided to study as many as possible of these ponds comparatively and in detail so as to bring out these similarities and ascertain what differences exist. Five ponds were finally chosen, the decision being conditioned by the dryness of the season which eliminated some of the ponds from consideration. In all, more than a dozen of these ponds were observed.

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Before World War II malaria was known only in the south-eastern countries of Europe. The territory afflicted with malaria spread from the Balkan region along the Danube and the Theiss rivers through Hungary to the south-eastern corner of Czechoslovakia, enclosing the southern tip of Slovakia and Subcarpathian Ruthenia. Systematic zoological investigations (Breindl and Komarek, 1940) have shown that anopheline mosquitoes live in Czechoslovakia, always in the plains and in the lower hilly territory. Two spp., A. bifurcatus (claviger) and A. maculipennis were found, the latter in two varieties, A. maculipennis typicus and A. maculipennis messae. These mosquitoes live in free nature only exceptionally. They are mostly encountered in warm and quiet stables and, sometimes, in human dwellings. Malaria was unknown in the western parts of Czechoslovakia since the 1850's (Pelnar, 1940). At the end of World War II, due to the considerable shifting of the civilian population and military troops, and also because of the changing epidemiological conditions in the war-torn counties, cases of malaria recently occurred also in the western districts of Czechoslovakia. Czechoslovak medical journals published reports of a few instances of malaria which were diagnosed immediately after World War II in two territories which are quite apart from each other: (1) in Southern Moravia, (2) in North-western Bohemia. (1) The territory of Southern Moravia afflicted with malaria is a flat, richly irrigated agricultural country. Some parts of this territory were badly damaged during the fighting in the Spring of 1945. Due to the large-scale devastation of stables and extermination of cattle, the mosquitoes have lost their predominantly zoophilic character and have found new hosts in the local population and the fighting armies. The German Army withdrew through Moravia, followed by the Russian Army which contained units of the Rumanian Army from the highly endemic Balkan territories. Many soldiers harbored malarial parasites and infected the mosquitoes which transferred the plasmodia to the local civilian population. In addition, the destroyed sewage and irrigation systems, as well as the numerous bomb craters filled with water during the spring floods became excellent mosquito breeding places during the hot summer. (2) The second area, in the north-western part of Bohemia, had a different source of infection. This territory is a lignitic coal mining district with many shallow shafts. Numerous deserted and sunken mines harbor undisturbed water pools which are strongly infested with mosquitoes. A great factory for the production of synthetic petrol was built in this territory during the war and laborers, including prisoners of war, were brought from all parts of Europe to work in it. Many of these workers came from the Balkan region and from Italy. Numerous persons ,among them represented untreated malarial subjects from Bulgaria, Yugoslavia, Italy, Greece and the Ukraine, who became the source of infection for the local population.

In Puerto Rico, Anopheles albimanus breeds prolifically in certain coastal lagoons having varying concentrations of sea water. The degree of salinity is altered by tides, evaporation and rainfall. These factors operate to create favorable or unfavorable conditions for mosquito breeding according to the tolerance of the species. It has been recognized that A. albimanus will not tolerate high concentrations of sea water and in certain instances this mosquito has been controlled by the introduction of sea water into land locked coastal lagoons (Washburn, 1933, and Tullock, 1937). The investigation here recorded was made in order to obtain more precise information on the limiting concentration of sea water required for the control of this species and the means by which such a concentration can be maintained in certain natural breeding places. It was found convenient to express the relative salinity in terms of per cent of sea water as determined by a hydrometer. Either a sodium chloride hydrometer or a urinometer may be calibrated from known dilutions of sea water. Eighty degrees Fahrenheit was taken as a convenient temperature and calibrations were made at five per cent intervals.