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■Bio-mathematics, Statistics and Nano-Technologies: Mosquito Control Strategies

located in the interior of the island and an urban population, concentrated in the capital,

which is growing rapidly, giving rise to the appearance of overcrowded neighbourhoods

without planning or urban infrastructure and with poor housing conditions [10].

18.3

PILOT STUDY I

18.3.1

Assessment of the use of substances with attractive power in ovitraps as a

method of monitoring Aedes aegypti, the vector of Zare ika and dengue in Cabo

Verde

The main strategies for vector monitoring and control based on methods for egg collec-

tion, larval research and adult mosquito collection. However, methods aimed at collecting

mosquito eggs are more appropriate to the peculiarities of Ae. aegypti than larval research

[11]. Oviposition traps (ovitrap) are the most sensitive and economical instrument for de-

tecting Aedes species, especially when infestation levels not revealed by larval indices

[12]. To improve the efficiency of ovitraps, attractant substances such as organic matter

infusions are used [13, 14]. Different studies report the Bacillus turigiensis var. israelien-

sis (Bti)-treated ovitrap technique in vector control as a promising strategy for detecting

Aedes species [15, 16]. In addition to being a biolarvicide, there is evidence that Bti acts as

a stimulant of Aedes species oviposition, improving the efficiency of ovitraps [9, 15, 17].

In addition, household substances, like table salt, have been tested in ovitraps to control

Ae. aegypti [14].

The aim of this study was to evaluate the attractiveness of substances tested in ovitraps

(salt, Bti and Bti + acacia infusion), as a complementary tool for monitoring Ae. aegypti,

the Zika and Dengue vector, in the city of Praia.

18.3.2

Material and Methods

Attractive and repellent substances for Ae. aegypti:

• Bacillus thurigiensis var. israeliensis, serotype 14, 0.2% (granules) VectoBac G,

Kenogard, Valent Biosciences Corporation. Lot 217-317-N8.

• Table salt diluted to 1.2%

• 10% acacia infusion (100 ml infusion for 1 litre of water). To prepare the infusion, 15

grams of acacia leaves wee used (Prosopis sp) for each litre of water. The prepared

solution rested for 7 days, before use, to allow for the fermentation of the organic

material.

Simulated field study to evaluate the effectiveness of substances tested in ovitraps (Bti,

Bti+infusion, Table salt) used to monitor Aedes aegypti:

For this test, oviposition traps (OVTs) were used to monitor Ae. aegypti in Praia [18],

treated with Bti, Bti + infusion and table salt. They were setup semi-randomly in eight

georeferenced locations in the Palmarejo district, distributed in a homogeneous way (18.2).

Four OVTs, were installed in each location containing: OVT Control (800 ml tap water),