ABSTRACT
Objetctive: This experimental study aimed to assess the preference of Gambusia affinis to mosquito larvae of An.gambiae s.s., Cx. quinquefasciatus and Aedes aegypti. Method: Three Gambusia affinis were introduced in a glass container with a dimension of 45cm x 25cmx 25cm. Three larvae densities were used, 90 (30 larvae per species), 120 (40 larvae per species), and 180 (60 larvae per species). Each density experiment was set in triplicate and monitored after 1, 2, 3, and 24 hours. No fish food was added to the container for larvae. Results: Results have shown that in all times A. aegypti has been the most preferred species by Gambusia affinis. Among the tested species, A. aegypti was most prayed with time and in different densities. In mixed models including density, species, and time there was no significant difference among the species predation. Conclusion: Preliminary results have shown that the appropriate choice of predators for each mosquito species can have a great impact on bio-control to substantially complement existing tools.
Objetivo: avaliar a preferência de Gambusia affinis por larvas de mosquito de An. gambiae s.s., Cx. quinquefasciatus e Aedes aegypti. Método: Três Gambusia affinis foram introduzidos em um recipiente de vidro com dimensões de 45cm x 25cm x 25cm. Foram utilizadas três densidades de larvas, 90 (30 larvas por espécie), 120 (40 larvas por espécie) e 180 (60 larvas por espécie). Cada experimento de densidade foi estabelecido em triplicado e monitorado após 1, 2, 3 e 24 horas. Nenhum alimento de peixe foi adicionado ao recipiente com larvas. Resultados: Os resultados mostraram que em todos os tempos o A. aegypti foi a espécie mais preferida por Gambusia affinis. Entre as espécies testadas, A. aegypti foi a mais predada com o tempo e em diferentes densidades. Em modelos mistos incluindo densidade, espécie e tempo, não houve diferença significativa entre a predação por espécies. Conclusão: Os resultados preliminares mostraram que a escolha apropriada de predadores para cada espécie de mosquito pode ter um grande impacto no bio-controle para complementar substancialmente as ferramentas existentes.
Subject(s)
Predatory Behavior , Biological Products , LarvaABSTRACT
Essential oil was extracted from Ocimum suave Willd leaves by water distillation and tested for repellency effectiveness against Anopheles gambiae adult mosquitoes. The percentage yield of the essential oil was 0.2%. Six concentrations of O. suave essential oil were applied on human skin of four volunteers, and the repellency effectiveness which was analyzed by PoloPlus (LeOra software version 1.0, 2002-2014), revealed promising RC50, RC75, RC90 and RC99 with their confidence limits as 0.1161 mg/cm2 (0.02067 - 0.1767 mg/cm2), 0.2823 mg/cm2 (0.22328 - 0.3654 mg/cm2), 0.4319 mg/cm2 (0.35226 - 0.58862 mg/cm2) and 0.98934 mg/cm2 (0.54731 - 0.99972 mg/cm2), respectively. O. suave essential oil exhibited high Anopheles mosquitos’ repellency effectiveness which merits further scientific attention for the development of natural repellents for the control of malaria and other mosquito borne diseases. These findings provides a scientific evidence and base for formulation for further mosquito repellency semi-field and field trials for the development of cheaper and affordable new mosquito repellent product(s) to meet human healthcare needs in the prevention and control of malaria and other mosquito transmitted infections.
ABSTRACT
Background. We assessed community knowledge; attitudes; and practices on malaria as well as acceptability to indoor residual spraying. Material and Methods. A cross-sectional survey was done in a community in Geita district (northwest Tanzania). Household heads (n=366) were interviewed Results. Knowledge on malaria transmission; prevention; and treatment was reasonable; 56of respondents associated the disease with mosquito bites; with a significant difference between education level and knowledge on transmission (P.001). Knowledge of mosquito breeding areas was also associated with education (illiterate: 22; literate: 59(P.001). Bed nets were used by 236 (64.5); and usage was significantly associated with education level (P.01). The level of bed net ownership was 77.3. Most respondents (86.3) agreed with indoor residual spraying of insecticides. Health facilities were the first option for malaria treatment by 47.3. Artemether-lumefantrine was the most common antimalarial therapy used. Conclusions. Despite reasonable knowledge on malaria and its preventive measures; there is a need to improve availability of information through proper community channels. Special attention should be given to illiterate community members. High acceptance of indoor residual spraying and high level of bed net ownership should be taken as an advantage to improve malaria control