TITLE:
Biotic and Abiotic Factors Influencing Microsporidia MB Infection in Anopheles coluzzii, Malaria Vector in Burkina Faso
AUTHORS:
Etienne Bilgo, Issiaka Saré, Issac Oumar Mahamat, Gladys Sanon, Abel Millogo, Maurice Konkobo, Abdoulaye Diabaté
KEYWORDS:
Diet, Relative Humidity, Temperature, Anopheles coluzzii, Microsporidia MB, Malaria
JOURNAL NAME:
Journal of Biosciences and Medicines,
Vol.13 No.2,
February
8,
2025
ABSTRACT: Introduction: A recent study in Kenya highlighted a promising advance in malaria control by demonstrating that infecting mosquitoes with the endosymbiont Microsporidia MB blocks Plasmodium transmission. However, the influence of biotic and abiotic factors such as diet, relative humidity (RH) and temperature on this infection remains poorly studied. This study, aimed to gain a better understanding of this relationship. Methods: To highlight the influence of diet quantity, we defined a range of 3 quantities: 0.00375 g, 0.015 g and 0.09 g. Each quantity was tested on two groups of larvae: a group of 150 larvae infected with Microsporidia MB (MB+), and a group of 150 larvae not infected with Microsporidia MB (MB−) (control group), each divided into three replicates of 50 larvae. Each replicate was fed each morning with the assigned quantity until the pupal stage. In addition to this factor, we investigated the influence of temperature and RH. We defined three temperature-RH combinations: 21˚C-80% RH, 39˚C-50% RH, and 27˚C-75% RH. Each combination was tested on two groups of larvae: a group of 150 MB+ larvae and a group of 150 MB− larvae, each divided into three replicates of 50 larvae. Each replicate was subjected to the assigned combination until pupation. Pupae that had reached the adult stage were tested by PCR to determine their Microsporidia MB infection status for each factor studied. Results: The results showed that only the lowest quantity (0.00375 g) significantly reduced the prevalence of Microsporidia MB compared with the medium quantity (chi-2 test, χ2 = 4.9088, df = 1, p = 0.02672) and the high quantity (chi-2 test, χ2 = 4.7958, df = 1, p = 0.02853). As for temperature and RH, the combination 39˚C-50% RH led to a significant reduction in the prevalence of Microsporidia MB compared with the combination 27˚C-75% RH (chi-2 test, χ2 = 6.3736, ddl = 1, p = 0.01158) and that 21˚C-80% RH (chi-2 test, χ2 = 9.983, ddl = 1, p = 0.00158). Conclusion: This work contributes to a better understanding of some key factors linked to Microsporidia MB infection in mosquitoes. However, further research on several generations is necessary to draw more comprehensive conclusions.