RESUMO
Background: The escalation of insecticide resistance across the World Health Organization (WHO) African region calls for the routine monitoring of insecticide resistance in mosquitoes. While pyrethroids are recommended for use and dichlorodiphenyltrichloroethane (DDT) has been prescribed, it is imperative to reevaluate their efficacy across diverse geographical settings. The extent of resistance among mosquitoes to DDT and lambda-cyhalothrin remains understudied in Ika North East, Delta State, Nigeria, where the yellow fever virus was reported in 2019. Materials and Methods: We investigated the susceptibility of female mosquitoes to DDT (4%) and lambda-cyhalothrin (0.05%) in this specific study area. Adult female mosquitoes of Anopheles gambiae, Culex quinquefasciatus, and Aedes albopictus, aged between 2 and 4 days, were subjected to these insecticides utilizing the WHO bioassay method. The assessment of knockdown was done between 10 and 60 min, then mortality after 24 h. Results: C. quinquefasciatus and A. albopictus mosquitoes exposed to DDT and lambda-cyhalothrin exhibited high susceptibility, resulting in complete mortality (100%); however, A. gambiae displayed resistance, with mortality rates of 19% and 76%, respectively . Notably, A. gambiae mosquitoes exposed to piperonyl butoxide (PBO)-DDT and PBO-lambda-cyhalothrin exhibited enhanced mortality, reaching 95% (indicating suspected resistance) and 100% (indicating susceptibility), respectively. Knockdown time (KDT) for 50% in mosquitoes exposed to lambda-cyhalothrin ranged from 3.94 to 33.51 min. Similarly, KDT model for 95% ranged from 19.04 to 84.15 min. Among the tested mosquito species, Culex mosquitoes exhibited the shortest knockdown resistance time for lambda-cyhalothrin, recorded at 3.94 min. Similarly, the KDT for DDT ranged from 24.97 to 187.06 min for 50% mortality and from 61.04 to 431.03 min for 95% mortality, respectively. Anopheles mosquitoes exposed to PBO + DDT recorded the lowest KDT. Conclusion: Our study underscores the potential of exercising caution in the use of DDT and lambda-cyhalothrin insecticides for the control of mosquitoes due to emerging resistance.
RESUMO
BACKGROUND: Acute abdomen is a clinical diagnosis and not a definitive one. The use of ultrasound in management and diagnosis of acute abdomen is rarely invoked in our environment. The importance of definite diagnosis in surgical and medical management cannot be overemphasized OBJECTIVE: To report a case of ultrasound diagnosis of retrocaecal appendicitis. METHODS: A nine-year-old male child presented with vomiting, vague abdominal pain, diarrhoea, and fever, which led to the following differential diagnoses; acute food poison gastro-enteritis, typhoid enteritis, malaria and acute appendicitis. He was investigated along these lines. He had abdominal ultrasonography and CT scan . RESULTS: The ultrasound showed evidence of acute appendicitis. The findings on CT and surgery confirmed the diagnosis. Post-operatively, he made uneventful recovery. CONCLUSION: The use of ultrasound in acute abdomen is rarely invoked in our environment which may lead to unquantifiable consequences both in management and complications.