**2. Materials and methods**

#### **2.1 Characterization of the study area**

The study has been conducted in the city of Caxias - MA, located between the coordinates 04°51′32 "south latitude and 43°21'22" longitude west. Its estimated population in 2018 is 164,224 inhabitants [16]. The climate is hot and humid with an average temperature of 28.2°C, having averages of the maximum of 27°C and averages of the minimum of 17°C, with two defined seasons, like rainy (January to June) and dry (July to December). The pluviometric index is between 1100 and 1500 mm/year, being the Itapecuru basin the main municipality, since it occupies 3567.40 km2 (68.4%) of the territory, in which there is a diversity of biomes and vegetation formation inserted in an ecotone area [17].

The area has been chosen randomly, where five zones have been selected according to the listing of districts of Caxias - MA, with records of dengue cases in the last 5 years.

#### **2.2 Immature collections**

#### *2.2.1 Sampling*

The city of Caxias presents a total of 55,769 properties. The zones drawn have a total of 6973 real estate [18]. They have been inspected 80 properties by neighborhood, chosen of random form. This sampling has been defined according to the formula for the Calculation of the Minimum Sample Size, proposed by [19] tolerating the margin of error of 5%.

The surveyed neighborhoods are among the most populous, have poor sanitation conditions, the sewers are open, some streets without adequate pavement, there is a regular lack of water from the public supply. Most homes have large backyards with

**111**

*Characterization of the Proliferation Sites of* Aedes aegypti *(Diptera: Culicidae)…*

The vessels inspected have been classified into groups according to

inspection of the internal and external residences [20, 21].

TR5 – storage (tank, barrel, filter, pot, bucket, drum);

TR7 – others (all containers that do not fit the others).

TR1 – vase (plant pots, and pot dishes); TR2 – bottle (bottles, cans, plastic);

TR6 – fixed (drains, grease box and wells);

and the presence or absence of organic matter.

letin for evaluation of larval density.

dichotomous key proposed [8, 9].

non-parametric analyzes have been used.

comparison of medians posteriori [26].

trees and the presence of domestic animals such as chickens, cats, dogs and even pigs. It is common to find accumulated garbage and water containers that serve as

The collections have been carried out during a year with a survey of 400 residences in the rainy season with repetition of the same ones in the dry season. All artificial containers that showed potential for *A. aegypti* proliferation have been analyzed, following the methodology of the National Health Foundation with

TR4 – building materials and car parts (materials used for construction and

The positive containers, which have been found in the presence of immature classified as to height (separated into three categories, 0–50, 51–100 and 100 cm above), exposure of breeding (total or partial exposure to the sun and/or shadow),

In the containers with larvae/pupae all specimens have been collected. In the deposits where it is not possible the total withdrawal of the immature ones was made in a numerical calculation of the area multiplied by the volume of the breeding place that measured with the aid of millimeter vial and tape measure. This calculation is used by endemic agents to estimate the population density of large breeding sites [21]. The larvae and pupae have been captured using plastic pipettes, and collected and conditioned in 10 ml hemolysis tubes containing 70% alcohol. Each tube stipulated a maximum number of 20 specimens, and the flasks have been identified with label containing the location data and type of deposit where they collected. Subsequently, they have been sent to the Laboratory of Medical Entomology (LABEM) to identify the specimens, and quantify and record the results in a bul-

The identification has been made through the direct observation of the morphological characters evidenced to the stereoscopic and the light microscope using the

The Kruskal-Wallis test (H) has been used to verify the differences between the number of immatures between zones, months and collection containers. The value of H calculated for each analysis has been compared to the value of H defined in the quantis table for Kruskal-Wallis test statistics. Whenever the calculated value is greater than that presented in the table at a certain degree of freedom, considered the number of groups compared, and where the value of p is less than or equal to 0.05, the hypothesis of medium males used, and continue with the Dunn test

All analyzes have been performed using the Statistical Package for Social Sciences

version 20.0 (SPSS Inc., Chicago, IL), the information compiled into database,

The number of immatures collected in the five zones of the municipality of Caxias, Maranhão, has been evaluated for the normal distribution, using the Shapiro-Wilk test. As these do not fit to the normal distribution, corresponding

*DOI: http://dx.doi.org/10.5772/intechopen.89959*

drinking fountains for the animals.

TR3 – tire (all types of tire);

following [22–25].

parts of cars);

*Characterization of the Proliferation Sites of* Aedes aegypti *(Diptera: Culicidae)… DOI: http://dx.doi.org/10.5772/intechopen.89959*

trees and the presence of domestic animals such as chickens, cats, dogs and even pigs. It is common to find accumulated garbage and water containers that serve as drinking fountains for the animals.

The collections have been carried out during a year with a survey of 400 residences in the rainy season with repetition of the same ones in the dry season. All artificial containers that showed potential for *A. aegypti* proliferation have been analyzed, following the methodology of the National Health Foundation with inspection of the internal and external residences [20, 21].

The vessels inspected have been classified into groups according to following [22–25].

TR1 – vase (plant pots, and pot dishes);

TR2 – bottle (bottles, cans, plastic);

TR3 – tire (all types of tire);

*Life Cycle and Development of Diptera*

The *A. aegypti* is a diurnal, anthropophilic mosquito with development of holometable, passing through the egg phase, four larval stages (L1, L2, L3 and L4), pupa and adult forms. The increase in the availability of human-made containers associated with climatic factors such as temperature rise, and variations in rainfall

Among the control methods, the most important are the chemicals, which have been used since the 1940s with the discovery of synthetic insecticides. Although several studies prove the resistance of mosquito populations to different classes of insecticides, they are still widely used for the control of *Aedes*. We also have the mechanical control that aims at the removal of breeding grounds, and the biological control that uses living organisms considered ecologically safe for the environment,

In order to combat *A. aegypti*, it is essential to regularly implement public water supply systems, basic sanitation and the adequate packaging of municipal solid waste, because a large part of the population is not aware of the problems generated

The present work aims to characterize the breeding sites most frequented by *A. aegypti*, to analyze the physical conditions in which these breeding sites are found to contribute for the actions to combat vector proliferation. As a consequence, outcome of this work will promote improvement in health and the environment, avoiding the disposal of waste in inappropriate places and an

The study has been conducted in the city of Caxias - MA, located between the coordinates 04°51′32 "south latitude and 43°21'22" longitude west. Its estimated population in 2018 is 164,224 inhabitants [16]. The climate is hot and humid with an average temperature of 28.2°C, having averages of the maximum of 27°C and averages of the minimum of 17°C, with two defined seasons, like rainy (January to June) and dry (July to December). The pluviometric index is between 1100 and 1500 mm/year, being the Itapecuru basin the main municipality, since it occupies

(68.4%) of the territory, in which there is a diversity of biomes and

The area has been chosen randomly, where five zones have been selected according to the listing of districts of Caxias - MA, with records of dengue cases in

The city of Caxias presents a total of 55,769 properties. The zones drawn have a total of 6973 real estate [18]. They have been inspected 80 properties by neighborhood, chosen of random form. This sampling has been defined according to the formula for the Calculation of the Minimum Sample Size, proposed by [19] tolerat-

The surveyed neighborhoods are among the most populous, have poor sanitation conditions, the sewers are open, some streets without adequate pavement, there is a regular lack of water from the public supply. Most homes have large backyards with

and relative humidity favor the vector development [8–11].

as an attempt to reduce the population density of the vector [12, 13].

by poor packaging of household waste and containers [14, 15].

adequate packaging of domestic containers.

vegetation formation inserted in an ecotone area [17].

**2.1 Characterization of the study area**

**2. Materials and methods**

3567.40 km2

the last 5 years.

*2.2.1 Sampling*

**2.2 Immature collections**

ing the margin of error of 5%.

**110**

TR4 – building materials and car parts (materials used for construction and parts of cars);

TR5 – storage (tank, barrel, filter, pot, bucket, drum);

TR6 – fixed (drains, grease box and wells);

TR7 – others (all containers that do not fit the others).

The positive containers, which have been found in the presence of immature classified as to height (separated into three categories, 0–50, 51–100 and 100 cm above), exposure of breeding (total or partial exposure to the sun and/or shadow), and the presence or absence of organic matter.

In the containers with larvae/pupae all specimens have been collected. In the deposits where it is not possible the total withdrawal of the immature ones was made in a numerical calculation of the area multiplied by the volume of the breeding place that measured with the aid of millimeter vial and tape measure. This calculation is used by endemic agents to estimate the population density of large breeding sites [21].

The larvae and pupae have been captured using plastic pipettes, and collected and conditioned in 10 ml hemolysis tubes containing 70% alcohol. Each tube stipulated a maximum number of 20 specimens, and the flasks have been identified with label containing the location data and type of deposit where they collected.

Subsequently, they have been sent to the Laboratory of Medical Entomology (LABEM) to identify the specimens, and quantify and record the results in a bulletin for evaluation of larval density.

The identification has been made through the direct observation of the morphological characters evidenced to the stereoscopic and the light microscope using the dichotomous key proposed [8, 9].

The number of immatures collected in the five zones of the municipality of Caxias, Maranhão, has been evaluated for the normal distribution, using the Shapiro-Wilk test. As these do not fit to the normal distribution, corresponding non-parametric analyzes have been used.

The Kruskal-Wallis test (H) has been used to verify the differences between the number of immatures between zones, months and collection containers. The value of H calculated for each analysis has been compared to the value of H defined in the quantis table for Kruskal-Wallis test statistics. Whenever the calculated value is greater than that presented in the table at a certain degree of freedom, considered the number of groups compared, and where the value of p is less than or equal to 0.05, the hypothesis of medium males used, and continue with the Dunn test comparison of medians posteriori [26].

All analyzes have been performed using the Statistical Package for Social Sciences version 20.0 (SPSS Inc., Chicago, IL), the information compiled into database,

mounted on Excel spreadsheets (2013) and Graph Pad Prism version 5.03 (La Jolla CA, USA), and from these obtained the percentages for the elaboration of tables and figures.

The values of p, significant at the mentioned level (5%), have been highlighted in the text, tables and graphs with an asterisk (\*). For p ≤ 0.05 an asterisk (\*) has been used, for p ≤ 0.01 two asterisks (\*\*) have been used and for p ≤ 0.0001 three asterisks (\*\*\*) adopted (26).
