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Two mitotypes of Busseola fusca (Fuller) (Lepidoptera: Noctuidae) named KI and KII, co-exist in Kenya. Individuals of KII are more widely distributed than those of KI. The present study assessed whether this was due to differences in their reproductive potential and/or in their resistance to the braconid Cotesia sesamiae Cameron, which is the most common larval parasitoid of B. fusca in the region. Two populations of the parasitoid, one from the coastal and one from the inland regions of Kenya, which differ in their ability to develop in B. fusca, were tested. Virgin KII females started to call sooner during the night than KI females. Female fecundity and egg viability were significantly lower for the heterogamous than the homogamous crosses. Cotesia sesamiae from the inland produced larger progeny in KI than in KII host. Cotesia sesamiae from the coast did not develop in either host. Despite their long time co-existence in the same geographical area, KII and KI conserved biological differences in terms of time of calling, fecundity, fertility and resistance against the larval parasitoid, C. sesamiae. This might explain the wider distribution of KII as compared to KI in Kenya. [ABSTRACT FROM AUTHOR]

The Asian pupal parasitoid, Xanthopimpla stemmator Thunberg, was imported into East Africa as a classical biological agent of lepidopteran cereal stem borers. Preference of X. stemmator females for four common borers of maize and sorghum; the crambid Chilo partellus (Swinhoe), the pyralid, Eldana saccharina Walker, and the noctuids, Busseola fusca Fuller and Sesamia calamistis Hampson, was investigated. Pre-adult experience of X. stemmator females did not influence choice of host. In dual choice tests, more B. fusca were attacked than E. saccharina, while E. saccharina were attacked more than Ch. partellus. Life table studies on three of the hosts revealed that the intrinsic rate of increase was highest when X. stemmator was reared on S. calamistis. Net reproductive rates, mean generation times and doubling times were not different between hosts. Results suggest that X. stemmator can be successfully reared on the three stem borer species and released in areas where any combination of the three hosts occurs. [ABSTRACT FROM AUTHOR]

Xanthopimpla stemmator (Thunberg), a solitary endoparasitoid of lepidopteran stemborer pupae, was recently imported into East Africa as a candidate biological control agent of gramineous stemborers. Suitability of Busseola fusca Fuller, Chilo partellus (Swinhoe), Eldana saccharina (Walker) and Sesamia calamistis Hampson, for the development of X. stemmator was studied in the laboratory. One- to 6-day-old laboratory reared pupae of the four stemborer species were exposed to naïve X. stemmator females. All host pupae and ages were acceptable for oviposition. The parasitoids inflicted multiple probe wounds on 67.8% of pupae exposed. B. fusca, C. partellus and S. calamistis were equally suitable with 56.4, 59.4 and 52.3%, respectively, of probed pupae leading to emergence of adult parasitoids. E. saccharina was less suitable with only 22.6% of probed pupae producing parasitoids. Emergence of parasitoids did not differ significantly across the six pupal ages for B. fusca and S. calamistis, but varied for C. partellus and E. saccharina . No parasitoids emerged from 6-day-old E. saccharina pupae. Realized fecundity of females reared on the four stemborer pupae showed that fewer progeny were produced by females emerging from E. saccharina than females reared on the other three stemborer species. Eldana saccharina may be a poor host for X. stemmator in Kenya, but this parasitoid is a potential candidate for biological control of B. fusca, C. partellus and S. calamistis. [ABSTRACT FROM AUTHOR]

Africa boasts high biodiversity while also being home to some of the largest and fastest-growing human populations. Although the current environmental footprint of Africa is low compared to other continents, the population of Africa is estimated at around 1.5 billion inhabitants, representing nearly 18% of the world's total population. Consequently, Africa's rich biodiversity is under threat, yet only 19% of the landscape and 17% of the seascape are under any form of protection. To effectively address this issue and align with the Convention on Biological Diversity's ambitious '30 by 30' goal, which seeks to protect 30% of the world's land and oceans by 2030, substantial funding and conservation measures are urgently required. In response to this critical challenge, as scientists and conservationists working in Africa, we propose five recommendations for future directions aimed at enhancing biodiversity conservation for the betterment of African society: (i) accelerate data collection, data sharing and analytics for informed policy and decision-making; (ii) innovate education and capacity building for future generations; (iii) enhance and expand protected areas, ecological networks and foundational legal frameworks; (iv) unlock creative funding channels for cutting-edge conservation initiatives; and (v) integrate indigenous and local knowledge into forward-thinking conservation strategies. By implementing these recommendations, we believe Africa can make significant strides towards preserving its unique biodiversity, while fostering a healthier society, and contributing to global conservation efforts.This article is part of the discussion meeting issue 'Bending the curve towards nature recovery: building on Georgina Mace's legacy for a biodiverse future'.

Background and Objective: Sexual assault is a major cause of injury, unplanned pregnancy, HIV infection, and mental health problems worldwide. In parts of sub-Saharan Africa, sexual assault has reached epidemic proportions. This study evaluated the efficacy of an empowerment and self-defense intervention for adolescent girls to decrease the incidence of sexual assault and harassment in Nairobi's large informal settlements., Methods: A prospective cohort of 1978 adolescents from 4 neighborhoods near Nairobi were taught empowerment, deescalation, and self-defense skills in six 2-hour sessions. The standard-of-care (SOC) group (n = 428) received a life skills class. Self-reported, anonymous survey data were collected at baseline and 10.5 months after intervention., Results: Annual sexual assault rates decreased from 17.9/100 person-years at baseline to 11.1 at follow-up (rate ratio = 1.61; 95% confidence interval [CI], 1.26-1.86; P < .001); there was no significant change in the SOC group (14.3 to 14.0, rate ratio = 1.02; 95% CI, 0.67-1.57, P = .92). Sexual assault disclosure in the intervention group increased from 56% to 75% (P = .006), compared with a constant incidence of disclosure (53%) in the SOC group. The majority (52.3%) of adolescents in the intervention group reported using skills learned to stop an assault., Conclusions: This intervention decreased sexual assault rates among adolescent girls in Kenya. The intervention was also associated with an increase in the disclosure of assaults, thereby enabling survivors to seek care and support and possibly leading to the identification and prosecution of perpetrators. This model should be adaptable to other settings both in Africa and globally., (Copyright © 2014 by the American Academy of Pediatrics.)

Polydnaviruses are rarely studied for their natural variation in immune suppressive abilities. The polydnavirus harboring braconid Cotesia sesamiae, a widespread endoparasitoid of Busseola fusca and Sesamia calamistis in sub-Saharan Africa exists as two biotypes. In Kenya, the western biotype completes development in B. fusca larvae. However, eggs of the coastal C. sesamiae are encapsulated in this host and ultimately, no parasitoids emerge from parasitized B. fusca larvae. Both biotypes develop successfully in S. calamistis larvae. Encapsulation activity by B. fusca larvae towards eggs of the avirulent C. sesamiae was detectable six hours post-parasitization. The differences in encapsulation of virulent and avirulent strains were associated with differences in nucleotide sequences and expression of a CrV1 polydnavirus (PDV) gene, which is associated with haemocyte inactivation in the Cotesia rubecula/Pieris rapae system. CrV1 expression was faint or absent in fat body and haemolymph samples from B. fusca parasitized by the avirulent C. sesamiae, which exhibited encapsulation of eggs. Expression was high in fat body and haemolymph samples from both B. fusca and S. calamistis larvae parasitized by the virulent C. sesamiae, encapsulation in the former peaking at the same time points as CrV1 expression in the latter. Non synonymous difference in CrV1 gene sequences between virulent and avirulent wasp suggests that variations in B. fusca parasitism by C. sesamiae may be due to qualitative differences in CrV1-haemocyte interactions.

Many clinical symptoms of malaria are associated with alterations in certain haematological parameters during acute and subclinical infections. Total leucocyte and erythrocyte counts, haemoglobin concentration, haematocrit and other minor indices, were investigated in five cohort groups of individuals resident in a malaria hyperendemic area of western Kenya. The groups included age- and sex-matched adults with acute Plasmodium falciparum malaria, aparasitaemic adults, children with acute malaria, aparasitaemic children and asymptomatic-parasitaemic school children. The study aimed at defining what constitutes immunity to malaria which may be important in the critical evaluation of malaria vaccine antigens. Anaemia was more severe in adults and children with acute malaria than in their age- and sex-matched aparasitaemic and asymptomatic-aparasitaemic school children. Lymphocyte counts were significantly higher in asymptomatic-aparasitaemic school children than in aparasitaemic adults, suggesting a possible functional role for lymphocytes in the anti-disease immunity in the former group.