Seasonal biting rate and transmission potentials of host-seeking black flies (Diptera: Simulidae) and its implications for human onchocerciasis control in parts of Imo River Basin, Nigeria
DOI:
https://doi.org/10.25081/jes.2025.v16.9194Keywords:
Biting and parity rates, Transmission potentials, Ivermectin treatment, Onchocerciasis, Rainy and dry seasons, Imo River BasinAbstract
Biting and parity status of black flies were evaluated between the transmission seasons (rainy and dry) after long-term Ivermectin treatments in Imo River Basin, Nigeria. Captured black flies were morphologically identified, dissected and assessed by standard protocol. Although more black flies were caught in the rainy season (54.3%) than dry season (45.3%), there was insignificant difference in the transmission parameters (P>0.05). Infection rate (0.2% versus 1.2%), parous rate (19.9% versus 22.4%), Infectivity rate (0.0% versus 0.0%), monthly biting rate (3,533.75 versus 3,095.5) bites/person/month, monthly parous biting rate (703.75 versus 771.5) bites and monthly transmission potential (0.0% versus 0.0%) were comparable for the seasons respectively. The data showed the existence of residual infection at the level of transmission likely to be insignificant to maintain parasite population.
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Atting, A. I., Ejezie, G. C., Braide, E. I., Opara, K. N., & Ekwe, A. (2006). Seasonal variations in human onchocerciasis transmission by black flies (Simulium damnosum sl) in a forest area of Cross River State, Nigeria. African Journal of Applied Zoology and Environmental Biology, 7, 14-18. https://doi.org/10.4314/ajazeb.v7i1.41139
Barbiero, V. K., & Trpis, M. (1984). Transmission of onchocerciasis by local black flies on the Forestone Rubber Plantation, Barbel, Liberia. American Journal of Tropical Medicine and Hygiene, 33(4), 586-594. https://doi.org/10.4269/ajtmh.1984.33.586
Basáñez, M. G., Razali, K., Renz, A., & Kelly, D. (2007). Density-dependent host choice by disease vectors: Epidemiological implications of the ideal free distribution. Transactions of the Royal Society of Tropical Medicine and Hygiene, 101(3), 256-269. https://doi.org/10.1016/j.trstmh.2006.08.009
Cheke, R. A., McCall, P. L., & Mass, J. (1997). The vector status of Simulium damnosum on the island of Bioko in Equatorial Guinea. Transactions of the Royal Society of Tropical Medicine and Hygiene, 91(2), 153-154. https://doi.org/10.1016/S0035-9203(97)90203-0
Dozie, I. N., Onwuliri, C. O., Nwoke, B. B., Anosike, J. C., & Okoli, N. J. (2006). Onchocerciasis in Imo State, Nigeria. I: The prevalence and distribution in the middle Imo River Basin, Nigeria. Nigerian Journal of Parasitology, 27(1), 6-22. https://doi.org/10.4314/njpar.v27i1.37830
Duke B. O. (1968). Studies on factors influencing the transmission of onchocerciasis. VI. The infective biting potential of Simulium damnosum in different bioclimatic zones and its influence on the transmission potential. Annals of Tropical Medicine and Parasitology, 62(2), 164-170.
Ezigbo, O. R., Nwoke, B. E. B., Ukaga, C. N., & Emukah, E. C. (2013). Impact assessment of repeated mass ivermectin treatment on onchocerciasis in Abia State, Nigeria. Journal of Basic and Applied Health, 3(12), 40-48.
Foucault, C., Ranque, S., Badiaga, S., Rovery, C., Raoult, D., & Brouqui, P. (2006). Oral ivermectin in the treatment of body lice. Journal of Infectious Diseases, 193(6), 474-476. https://doi.org/10.1086/499279
Gutman, J., Emukah, E., Okpala, N., Okoro, C., Obasi, A., Miri, E. S., & Richards Jr., F. O. (2010). Effects of annual mass treatment with ivermectin for onchocerciasis on the prevalence of intestinal helminths. American Journal of Tropical Medicine and Hygiene, 83(3), 534-541. https://doi.org/10.4269/ajtmh.2010.10-0033
Habbema, J. D. F., Alley, E. S., Plaisier, A. P., van Oortmarssen, G. J., & Remme, J. H. F. (1992). Epidemiological modelling for onchocerciasis control. Parasitology Today, 8(3), 99-103.
Jürgens, S., & Schulz-Key, H. (1990). Effect of ivermectin on the vertical distribution of Onchocerca volvulus microfilariae in the skin. Tropical Medicine and Parasitology, 41(2), 165-168.
Kovats, R. S., Campbell-Lendrum, D. H., McMichael, A. J., Woodward, A., & Cox, J. S. H. (2001). Early effects of climate change: Do they include changes in vector-borne diseases? Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences, 356(1411), 1057-1068. https://doi.org/10.1098/rstb2001.0894
Lindblade, K. A., Richards, M., Richards, J., Gonzalez, R. J., Cruz-Ortiz, N., Zea-Flores, G., Morales, A. L., Sauerbrey, M., Castro, J., Catú, E., Arana, B., Richards Jr., F. O., & Klein, R. E. (2009). Exposure of seasonal migrant workers to Onchocerca volvulus on coffee plantations in Guatemala. The American Journal of Tropical Medicine and Hygiene, 81(3), 438-442. https://doi.org/10.4269/ajtmh.2009.81.438
Maikaje, D. B., Dibal, D. M., Umar, Y. A., & Egbe, N. E. (2015). Investigation on the transmission potentials of Simulium damnosum and the risk of human onchocerciasis in Kaduna metropolis, Kaduna State, Nigeria. International Journal of Medicine and Biomedical Research, 7(7), 217-222. https://doi.org/10.5897/JPHE2015.0720
Mokry, J. E. (1980). A method for estimating the age of field-collected female Simulium damnosum s.l. (Diptera: Simuliidae). Tropenmedizin und Parasitologie, 31(1), 121-127.
Nnadozie, R. I. A., Onyenwe, L., Ibediugha, B. N., & Okorie, A. G. (2018). Entomological evaluation by dissection of adult Simulium damnosum complex for larvae of Onchocerca volvulus following CDTI in Amagu Agba community, Ishielu, Ebonyi State, Nigeria. American Journal of Public Health Research, 6(2), 26-30.
Nwoke B. E. (1990). The socio-economic aspects of human onchocerciasis in Africa: present appraisal. Journal of Hygiene, Epidemiology, Microbiology, and Immunology, 34(1), 37-44.
Nwoke, B. E. B. (1993). Onchocerciasis control: A training guide in entomological evaluation. Owerri, Nigeria: Imo State University Press.
Nwoke, B. E. B., Edungbola, L. D., Mencia, B. S., Njoku, A. J., Abanobi, O. C., Nkwogu, E. C., Nduka, F. O., & Oguariri, F. M. (1994). Human onchocerciasis in the rainforest zone of southeastern Nigeria. I: Rapid assessment for community diagnosis in the Imo River Basin, Nigeria. Nigerian Journal of Parasitology, 15, 46-58.
Okwa, O. O., Olusola, O. O. A., & Adelari, O. F. (2009). Onchocerciasis among women in rural Guinea savannah ecotype in Nigeria: Social implications for control. Journal of Tropical Medicine and Health, 37(4), 135-140. https://doi.org/10.2149/tmh.2008-18
Traore, M. O., Sarr, M. D., Badji, A., Bissan, Y., Diawara, L., Doumbia, K., Goita, S. F., Konate, L., Mounkoro, K., Seck, A. F., Toe, L., Toure, S., & Remme, J. H. F. (2012). Proof of principle of onchocerciasis elimination with ivermectin treatment in endemic foci in Africa: First results of a study in Mali and Senegal. PLOS Neglected Tropical Diseases, 6(9), e1825. https://doi.org/10.1371/journal.pntd.0001825
Ukpai, O. M., & Ezeji, J. C. (2003). Social implications of Onchocerca dermatitis among females in endemic communities in Okigwe LGA of Imo State, Nigeria. Nigerian Journal of Parasitology, 24(1), 59-64. https://doi.org/10.4314/njpar.v24i1.37806
Uttah, E. C., Simonson, P., Pedersen, E. M., & Udonsi, J. K. (2004). Sporadic onchocerciasis in the lower Imo River Basin, Nigeria. African Journal of Applied Zoology and Environmental Biology, 6, 76-85. https://doi.org/10.4314/ajazeb.v6i1.41179
Walsh, J. F., Davies, J. B., Le Berre, R., & Garms, R. (1978). Standardization of criteria for assessing the effect of Simulium control in onchocerciasis control programmes. Transactions of the Royal Society of Tropical Medicine and Hygiene, 72(6), 675-676. https://doi.org/10.1016/0035-9203(78)90039-1
Wanji, S., Kengne-Ouafo, J. A., Esum, M. E., Chounna, P. W. N., Tendongfor, N., Adzemye, B. F., Eyong, J. E. E., Jato, I., Datchoua-Poutcheu, F. R., Kah, E., Enyong, P., & Taylor, D. W. (2015). Situation analysis of parasitological and entomological indices of onchocerciasis transmission in three drainage basins of the rainforest of South West Cameroon after a decade of ivermectin treatment. Parasites & Vectors, 8, 202. https://doi.org/10.1186/s13071-015-0817-2
Wanji, S., Tendongfor, N., Esum, M. E., & Enyong, P. (2002). Chrysops silacea biting densities and transmission potential in an endemic area of human loiasis in south-west Cameroon. Tropical Medicine & International Health, 7(4), 371-377. https://doi.org/10.1046/j.1365-3156.2002.00845.x
Wealtheral, N. (1995). Transmission potentials of Onchocerca volvulus and the associated intensity of onchocerciasis in Sudan savannah area. Tropical Medicine and Parasitology, 29, 340-346.
WHO. (2006). Preventive chemotherapy in human helminthiasis: Coordinated use of antihelminthic drugs in control interventions: A manual for health professionals and programme managers. World Health Organization, Geneva.
.