Detection and Co-occurrence of kdr (F1534C and S989P) Mutations in Multiple Insecticides Resistant Aedes aegypti (Diptera: Culicidae) in Nigeria.

The outbreak of yellow fever virus transmitted by Aedes aegypti has been of major concern in Nigeria, this mosquito also transmits several other arboviruses globally. The control of many vectors of mosquito-borne diseases relies heavily on the use of insecticides. Therefore, constant monitoring of insecticide resistance status and associated mechanisms is crucial within the local mosquito population. Here, we determined the resistance profile of adult Ae. aegypti from Majidun and Oke Ota communities, Ikorodu Local Government Area of Lagos State, Nigeria to different classes of insecticides using WHO procedures. The resistant phenotypes of Ae. aegypti were screened for the presence of kdr mutations F1534C, S989P, and V1016G, which have been implicated in insecticide resistance in yellow fever vectors. A high level of resistance to DDT and pyrethroids was recorded in Ae. aegypti in this study, although possible resistance to deltamethrin, one of the pyrethroids was reported in one of the locations. Resistance to bendiocarb was recorded in the Majidun community while Ae. aegypti in both locations were susceptible to malathion. The presence of F1534C mutation associated with DDT and deltamethrin resistance in Ae. aegypti population, and the presence of S989P mutation were detected singly and in co-occurrence with F1534C for the first time in Africa, while V1016G mutation was not detected in this study. The role of these mutations in resistance phenotype expressed in Ae. aegypti in larger populations needs to be established.

Knowledge, attitude and perception of West Africans towards COVID-19: a survey to inform public health intervention.

BACKGROUND: The first case of the novel coronavirus disease-2019 (COVID-19) in West Africa was first confirmed in Nigeria in February 2020. Since then, several public health interventions and preventive measures have been implemented to curtail transmission of the causative agent, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Therefore, this study was performed to assess the knowledge, attitudes, and perceptions of West Africans towards COVID-19. METHODS: An online survey was conducted between 29 September to 29 October 2020 among West Africans. Thirty-three survey questions were designed to collect sociodemographic data and participants' knowledge, attitude and perception towards COVID-19. The study targeted all West African nationals who were 18 years and above, and willing to participate in the study. Participants were either in-country or abroad. RESULTS: Overall, 1106 respondents (≥18 years) from 16 West African countries, with about 12.1% of them residing outside the West African subregion, participated in the survey. The respondents had an average COVID-19 knowledge score of 67.82 ± 8.31, with knowledge of the disease significantly associated with the country of residence (p = 0.00) and marginally (p = 0.05) so with settlement types (i.e., urban, suburban and rural areas). Most respondents (93.4%) could identify the main COVID-19 symptoms, and 73.20% would consult a healthcare professional if infected with SARS-CoV-2. Also, 75.2% of the respondents are willing to receive the COVID-19 vaccine, whereas 10.40% and 14.40% are unwilling and undecided, respectively. Perceptions of what constitute COVID-19 preventive measures were highly variable. Approximately, 8% of the respondents felt that their government responded excellently in managing the pandemic while a third felt that the response was just good. Also, more than half (54%) opined that isolation and treatment of COVID-19 patients is a way of curbing SARS-CoV-2 spread. CONCLUSIONS: Most West Africans have basic knowledge of COVID-19 and showed a positive attitude, with likely proactive practice towards the disease. However, results showed that these varied across countries and are influenced by the types of settlements. Therefore, the health and education authorities in various countries should develop focused measures capturing people in different settlements to improve their preventative measures when designing public health interventions for COVID-19 and any future epidemics or pandemics.

Genetic Diversity and Utilization of Cultivated Eggplant Germplasm in Varietal Improvement.

Eggplant is the fifth economically most important vegetable in the Solanaceae family after tomato, potato, chili, and tobacco. Apart from the well-cultivated brinjal or aubergine eggplant (Solanum melongena L.), two other underutilized eggplant species, the African eggplant (S. macrocarpon L.) and the scarlet eggplant (S. aethiopicum L.), were also cultivated with local importance where the leaves and fruits are used for food and medicinal purposes. The major objectives of the eggplant breeding program are to improve fruit quality, increase yield performance through heterosis breeding, and introduce pest and disease resistances from wild relatives. Europe and Asia hold a wide collection of germplasm resources with significant potential for genetic improvement. While cultivated eggplant is susceptible to several fungi and bacteria, many wild relatives offer potential resistance to these pathogens. In this paper, we review the genetic resources and diversity of cultivated eggplant and its wild relatives. As a point of departure, we examine the economic importance, domestication, taxonomy characterization, and relationships of the crop and its wild relatives. The importance of evaluating and safeguarding wild relatives is highlighted, as crop wild relatives are highly underrepresented. A key section in this study is an overview dedicated to genetic resources, resistance to biotic and abiotic stresses, pre-breeding, and breeding for sustainable eggplant production.

Knowledge, attitudes and perception of communities on mosquitoes and its control practices in Lagos State, Nigeria.

INTRODUCTION: evidence-based mosquito control strategy is important for efficient and effective delivery of mosquito control interventions. This is hinged on effective community participation and thorough understanding of the Knowledge Attitude and Practices (KAPs) to achieve desired result. Such community dynamics are often understudied. We designed this study to assess the perception of four local communities on aspects of mosquito behavior, prevention and control in Lagos State, Nigeria. METHODS: a cross-sectional survey was carried out using pretested semi-structured questionnaires to assess socio-demographic factors and KAPs in Kosofe, Alimosho, Ibeju-Lekki and Badagry Local Government Areas of Lagos State, Nigeria. Data analysis was carried out using IBM SPSS version 23. RESULTS: a total of 746 questionnaires were analyzed. Socio-demographic profile of the sampled population reveals that majority of the study population (73.1%) was between 18 and 40 years which constitute 49% males and 51% females. The knowledge of mosquito as a disease vector was high among the respondents which correlates with their level of education (P<0.05). The use of insecticide aerosols and Insecticides Treated Nets (ITNs) are the main control measures employed for mosquito control by respondents. Cost, convenience of usage and awareness majorly influenced the type of control measures that respondents adopt. Reasons such as not being easy to setup, skin irritation and the filling of being caged are reasons why some individuals do not use ITNs. Indoors, 32.4% of the respondents indicate the use of dichlorvos (DDVP) for household control of mosquitoes. CONCLUSION: the knowledge of mosquito control is high among middle aged individuals in Lagos State. Insecticide aerosols and ITNs are two major mosquito control methods used with DDVP insecticides frequently used indoors. This can inform the design of appropriate control methods in Lagos State.

First report of AChE1 (G119S) mutation and multiple resistance mechanisms in Anopheles gambiae s.s. in Nigeria.

Susceptibility and PBO synergist bioassays were done using 3-5 days old female Anopheles mosquito collected from Lagos State, Nigeria with WHO test papers DDT (4%), permethrin (0.75%), Bendiocarb (1%) and PBO (4%) according to standard procedures. The activities of cytochrome P450s, glutathione S-transferase and carboxylesterases were determined using biochemical assays. The presence of kdr-w, kdr-e and Ace-1R mutations were examined using molecular assays. Resistance to DDT and permethrin in An gambiae s.s from the four Local Government Areas (LGAs) was recorded while suspected resistance to bendiocarb was recorded in mosquitoes from Alimosho and Kosofe LGAs. PBO synergist reduced the knockdown time and also recorded significantly (P < 0.05) higher 24 hrs percentage mortality compared to non-synergized bioassays. Increased activities of detoxifying enzymes was recorded in wild mosquito compared to the insecticides susceptible laboratory strain and this was significant (P < 0.05) in P450s, esterase α and ß. Kdr-w was detected in An. gambiae s.s from all the LGAs, kdr-e (L1014S) was detected in Alimosho, Kosofe and Ibeju-Lekki, while the Ace-1R gene was detected in Alimosho and Kosofe. Results from this study provide evidence for resistance of An. gambiae from Lagos State to multiple classes of neurotoxic insecticides with multiple resistance mechanisms to these insecticides.