A note on the occurrence of Varroa destructor in Singida, Tanzania
During our beekeeping experience in Tanzania in January 2018 we found several colonies which were infested with Varroa destructor in the Singida region, Ikungi district. Yet, no devastating picture or visual detection of symptoms, like spotty brood nest, deformed wings, deformed workers etc. could be found in both strong and weak colonies and infestation rates per hive were low. The first scientific report of Varroa mites in Tanzania only dates to 2014 (Mumbi et al., 2014). This suggests, that the parasite is spreading rather fast.
A similar picture has been reported in other African countries, as reflected in the review by (Pirk et al., 2016). One of the latest studies sampled colonies from Ghana (Llorens-Picher et al., 2017). Out of 49 colonies, 89% were infested with Varroa destructor, whereas the first report of Varroa in Ghana dates back only 8 years (Fazier et al., 2010). High infestation rates are now thought to be either reflecting the local subspecies of Apis mellifera adansonii being more tolerant or an invasion wave of V. destructor taking place right now.
References
Fazier, M., Muli, E., Conklin, T., Schmehl, D., Torto, B., Frazier, J., . . . Raina, S. (2010). A scientific note on Varroa destructor found in East Africa; threat or opportunity? Apidologie, 41(4), 463-465. doi:10.1051/apido/2009073
Llorens-Picher, M., Higes, M., Martin-Hernandez, R., De la Rua, P., Munoz, I., Aidoo, K., . . . Meana, A. (2017). Honey bee pathogens in Ghana and the presence of contaminated beeswax. Apidologie, 48(6), 732-742. doi:10.1007/s13592-017-0518-2
Mumbi, C., Richard Mwakatobe, A., Issa, H., Mpinga, Richard, A., Machumu, R., . . . Machumu. (2014). Parasitic mite, Varroa species (Parasitiformes: Varroidae) infesting the colonies of African honeybees, Apis mellifera scutellata (Hymenoptera: Apididae) in Tanzania (Vol. 188).
Pirk, C. W. W., Strauss, U., Yusuf, A. A., Démares, F., & Human, H. (2016). Honeybee health in Africa—a review. Apidologie, 47(3), 276-300. doi:10.1007/s13592-015-0406-6