Risk Management in Smallholder Cattle Farming: A Hypothetical Insurance Approach in Western Kenya

Smallholder cattle farming is an important livelihood strategy in most developing countries like Kenya. However, tropical diseases in Africa often wipe out these valuable assets. This paper focuses on mitigation of cattle disease risks through a hypothetical insurance scheme. The study is based on data from a survey conducted on a purposive sample of 300 smallholder cattle farmers in Kakamega and Siaya districts of Western Kenya. Descriptive measures and a regression model were used in the analysis. Results of the study showed that most farmers (91.3%) were willing to participate in the cattle insurance scheme. Also, the farmers observed that the scheme would enable them to increase their herd sizes and change their breed composition. The farmer's mean Willingness To Pay (WTP) for the scheme would be determined by their gender, income, cultural norms, cattle breed and economic value/price of the animal kept. This paper recommends establishment of a formal cattle insurance scheme; and economic empowerment of both male and female farmers to encourage adoption of the scheme, as well as educating the farmers on how to integrate the scheme within their cultural norms to ensure it's sustainability.Cattle, smallholder livelihoods, disease risks, insurance, Livestock Production/Industries, Risk and Uncertainty,

Agricultural and Finance Intervention Increased Dietary Intake and Weight of Children Living in HIV-Affected Households in Western Kenya.

We tested whether a multisectoral household agricultural and finance intervention increased the dietary intake and improved the nutritional status of HIV-affected children. Two hospitals in rural Kenya were randomly assigned to be either the intervention or the control arm. The intervention comprised a human-powered water pump, microfinance loan for farm commodities, and training in sustainable farming practices and financial management. In each arm, 100 children (0-59 mo of age) were enrolled from households with HIV-infected adults 18-49 y old. Children were assessed beginning in April 2012 and every 3 mo for 1 y for dietary intake and anthropometry. Children in the intervention arm had a larger increase in weight (β: 0.025 kg/mo, P = 0.030), overall frequency of food consumption (β: 0.610 times · wk-1 · mo-1, P = 0.048), and intakes of staples (β: 0.222, P = 0.024), fruits and vegetables (β: 0.425, P = 0.005), meat (β: 0.074, P < 0.001), and fat (β: 0.057, P = 0.041). Livelihood interventions have potential to improve the nutrition of HIV-affected children. This trial was registered at clinicaltrials.gov as NCT01548599

Assessment of submicroscopic infections and gametocyte carriage of Plasmodium falciparum during peak malaria transmission season in a community-based cross-sectional survey in western Kenya, 2012

Additional file 2. Proportion of parasite and gametocyte presence in 996 samples tested by 18S-and Pfs25-NASBA stratified by risk factor and intervention. Proportions are reported in overall and each area, $NA: not analysed because parasitaemia causes anaemia

Assessment of molecular markers for anti-malarial drug resistance after the introduction and scale-up of malaria control interventions in western Kenya

Background Although it is well known that drug pressure selects for drug-resistant parasites, the role of transmission reduction by insecticide-treated bed nets (ITNs) on drug resistance remains unclear. In this study, the drug resistance profile of current and previous first-line anti-malarials in Kenya was assessed within the context of drug policy change and scale-up of ITNs. National first-line treatment changed from chloroquine (CQ) to sulphadoxine-pyrimethamine (SP) in 1998 and to artemether-lumefantrine (AL) in 2004. ITN use was scaled-up in the Asembo, Gem and Karemo areas of western Kenya in 1997, 1999 and 2006, respectively. Methods Smear-positive samples (N = 253) collected from a 2007 cross-sectional survey among children in Asembo, Gem and Karemo were genotyped for mutations in pfcrt and pfmdr1 (CQ), dhfr and dhps (SP), and at pfmdr-N86 and the gene copy number in pfmdr1 (lumefantrine). Results were compared among the three geographic areas in 2007 and to retrospective molecular data from children in Asembo in 2001. Results In 2007, 69 and 85% of samples harboured the pfmdr1-86Y mutation and dhfr/dhps quintuple mutant, respectively, with no significant differences by study area. However, the prevalence of the pfcrt-76T mutation differed significantly among areas (p <0.02), between 76 and 94%, with the highest prevalence in Asembo. Several 2007 samples carried mutations at dhfr-164L, dhps-436A, or dhps-613T. From 2001 to 2007, there were significant increases in the pfcrt-76T mutation from 82 to 94% (p <0.03), dhfr/dhps quintuple mutant from 62 to 82% (p <0.03), and an increase in the septuple CQ and SP combined mutant haplotype, K 76 Y 86 I 51 R 59 N 108 G 437 E 540 , from 28 to 39%. The prevalence of the pfmdr1-86Y mutation remained unchanged. All samples were single copy for pfmdr1. Conclusions Molecular markers associated with lumefantrine resistance were not detected in 2007. More recent samples will be needed to detect any selective effects by AL. The prevalence of CQ and SP resistance markers increased from 2001 to 2007 in the absence of changes in transmission intensity. In 2007, only the prevalence of pfcrt-76T mutation differed among study areas of varying transmission intensity. Resistant parasites were most likely selected by sustained drug pressure from the continued use of CQ, SP, and mechanistically similar drugs, such as amodiaquine and cotrimoxazole. There was no clear evidence that differences in transmission intensity, as a result of ITN scale-up, influenced the prevalence of drug resistance molecular markers

Persistently high estimates of late night, indoor exposure to malaria vectors despite high coverage of insecticide treated nets

Background It has been speculated that widespread and sustained use of insecticide treated bed nets (ITNs) for over 10 years in Asembo, western Kenya, may have selected for changes in the location (indoor versus outdoor) and time (from late night to earlier in the evening) of biting of the predominant species of human malaria vectors (Anopheles funestus, Anopheles gambiae sensu stricto, and Anopheles arabiensis). Methods Mosquitoes were collected by human landing catches over a six week period in June and July, 2011, indoors and outdoors from 17 h to 07 h, in 75 villages in Asembo, western Kenya. Collections were separated by hour of the night, and mosquitoes were identified to species and tested for sporozoite infection with Plasmodium falciparum. A subset was dissected to determine parity. Human behavior (time going to bed and rising, time spent indoors and outdoors) was quantified by cross-sectional survey. Data from past studies of a similar design and in nearby settings, but conducted before the ITN scale up commenced in the early 2000s, were compared with those from the present study. Results Of 1,960 Anopheles mosquitoes collected in 2011, 1,267 (64.6%) were morphologically identified as An. funestus, 663 (33.8%) as An. gambiae sensu lato (An. gambiae s.s. and An. arabiensis combined), and 30 (1.5%) as other anophelines. Of the 663 An. gambiae s.l. collected, 385 were successfully tested by PCR among which 235 (61.0%) were identified as An. gambiae s.s. while 150 (39.0%) were identified as An. arabiensis. Compared with data collected before the scale-up of ITNs, daily entomological inoculation rates (EIRs) were consistently lower for An. gambiae s.l. (indoor EIR = 0.432 in 1985–1988, 0.458 in 1989–1990, 0.023 in 2011), and An. arabiensis specifically (indoor EIR = 0.532 in 1989–1990, 0.039 in 2009, 0.006 in 2011) but not An. funestus (indoor EIR = 0.029 in 1985–1988, 0.147 in 1989–1990, 0.010 in 2009 and 0.103 in 2011). Sporozoite rates were lowest in 2009 but rose again in 2011. Compared with data collected before the scale-up of ITNs, An. arabiensis and An. funestus were more likely to bite outdoors and/or early in the evening (p 90% of exposure of non-ITN users to mosquito bites occurring while people were indoors in all years. The proportion of bites occurring among non-ITN users while they were asleep was ≥90% for all species except for An. arabiensis. For this species, 97% of bites occurred while people were asleep in 1989–1990 while in 2009 and 2011, 80% and 84% of bites occurred while people were asleep for those not using ITNs. Assuming ITNs prevent a theoretical maximum of 93.7% of bites, it was estimated that 64-77% of bites would have occurred among persons using nets while they were asleep in 1989–1990, while 20-52% of bites would have occurred among persons using nets while they were asleep in 2009 and 2011. Conclusions This study found no evidence to support the contention that populations of Anopheles vectors of malaria in Asembo, western Kenya, are exhibiting departures from the well-known pattern of late night, indoor biting characteristic of these typically highly anthropophilic species. While outdoor, early evening transmission likely does occur in western Kenya, the majority of transmission still occurs indoors, late at night. Therefore, malaria control interventions such as ITNs that aim to reduce indoor biting by mosquitoes should continue to be prioritized

Safety and PCR monitoring in 161 semi-immune Kenyan adults following controlled human malaria infection

BACKGROUND. Naturally acquired immunity to malaria is incompletely understood. We used controlled human malaria infection (CHMI) to study the impact of past exposure on malaria in Kenyan adults in relation to infection with a non-Kenyan parasite strain. METHODS. We administered 3.2 × 103 aseptic, purified, cryopreserved Plasmodium falciparum sporozoites (Sanaria PfSPZ Challenge, NF54 West African strain) by direct venous inoculation and undertook clinical monitoring and serial quantitative PCR (qPCR) of the 18S ribosomal RNA gene. The study endpoint was met when parasitemia reached 500 or more parasites per μL blood, clinically important symptoms were seen, or at 21 days after inoculation. All volunteers received antimalarial drug treatment upon meeting the endpoint. RESULTS. One hundred and sixty-one volunteers underwent CHMI between August 4, 2016, and February 14, 2018. CHMI was well tolerated, with no severe or serious adverse events. Nineteen volunteers (11.8%) were excluded from the analysis based on detection of antimalarial drugs above the minimal inhibitory concentration or parasites genotyped as non-NF54. Of the 142 volunteers who were eligible for analysis, 26 (18.3%) had febrile symptoms and were treated; 30 (21.1%) reached 500 or more parasites per μL and were treated; 53 (37.3%) had parasitemia without meeting thresholds for treatment; and 33 (23.2%) remained qPCR negative. CONCLUSION. We found that past exposure to malaria, as evidenced by location of residence, in some Kenyan adults can completely suppress in vivo growth of a parasite strain originating from outside Kenya. TRIAL REGISTRATION. ClinicalTrials.gov NCT02739763. FUNDING. Wellcome Trust

Summary Brief: Heifer study on climate-smart agriculture adoption rates amongst goat farming households in three districts of Nepal and the impact on key environmental and economic indicators

This info brief provides an executive overview of the research methods and key finding of a series of information briefs. The briefs were developed to assess the role of Heifer Nepal programming in supporting the adoption of Climate-Smart Agriculture (CSA) practices amongst Heifer supported goat cooperatives, and their impact on a range of environmental and economic indicators. The recommendations of the analysis are intended to further strengthen the integration of climate change considerations into Heifer Nepal’s programming, with the goal of raising overall household incomes amongst supported households through means that have minimal negative impact on the environment. The research was conducted in three districts encompassing the main agro-ecological contexts in which Heifer Nepal works

Horizontal transmission of the symbiont Microsporidia MB in Anopheles arabiensis

&lt;jats:p&gt;The recently discovered &lt;jats:italic&gt;Anopheles&lt;/jats:italic&gt; symbiont, &lt;jats:italic&gt;Microsporidia MB&lt;/jats:italic&gt;, has a strong malaria transmission-blocking phenotype in &lt;jats:italic&gt;Anopheles arabiensis&lt;/jats:italic&gt;, the predominant &lt;jats:italic&gt;Anopheles gambiae&lt;/jats:italic&gt; species complex member in many active transmission areas in eastern Africa. The ability of &lt;jats:italic&gt;Microsporidia MB&lt;/jats:italic&gt; to block &lt;jats:italic&gt;Plasmodium&lt;/jats:italic&gt; transmission together with vertical transmission and avirulence makes it a candidate for the development of a symbiont-based malaria transmission blocking strategy. We investigate the characteristics and efficiencies of &lt;jats:italic&gt;Microsporidia MB&lt;/jats:italic&gt; transmission between &lt;jats:italic&gt;An. arabiensis&lt;/jats:italic&gt; mosquitoes. We show that &lt;jats:italic&gt;Microsporidia MB&lt;/jats:italic&gt; is not transmitted between larvae but is effectively transmitted horizontally between adult mosquitoes. Notably, &lt;jats:italic&gt;Microsporidia MB&lt;/jats:italic&gt; was only found to be transmitted between male and female &lt;jats:italic&gt;An. arabiensis&lt;/jats:italic&gt;, suggesting sexual horizontal transmission. In addition, &lt;jats:italic&gt;Microsporidia MB&lt;/jats:italic&gt; cells were observed infecting the &lt;jats:italic&gt;An. arabiensis&lt;/jats:italic&gt; ejaculatory duct. Female &lt;jats:italic&gt;An. arabiensis&lt;/jats:italic&gt; that acquire &lt;jats:italic&gt;Microsporidia MB&lt;/jats:italic&gt; horizontally are able to transmit the symbiont vertically to their offspring. We also investigate the possibility that &lt;jats:italic&gt;Microsporidia MB&lt;/jats:italic&gt; can infect alternate hosts that live in the same habitats as their &lt;jats:italic&gt;An. arabiensis&lt;/jats:italic&gt; hosts, but find no other non-anopheline hosts. Notably, &lt;jats:italic&gt;Microsporidia MB&lt;/jats:italic&gt; infections were found in another primary malaria African vector, &lt;jats:italic&gt;Anopheles funestus s.s&lt;/jats:italic&gt;. The finding that &lt;jats:italic&gt;Microsporidia MB&lt;/jats:italic&gt; can be transmitted horizontally is relevant for the development of dissemination strategies to control malaria that are based on the targeted release of &lt;jats:italic&gt;Microsporidia MB&lt;/jats:italic&gt; infected &lt;jats:italic&gt;Anopheles&lt;/jats:italic&gt; mosquitoes.&lt;/jats:p&gt

Chimpanzee adenovirus vaccine provides multispecies protection against Rift Valley Fever

Rift Valley Fever virus (RVFV) causes recurrent outbreaks of acute life-threatening human and livestock illness in Africa and the Arabian Peninsula. No licensed vaccines are currently available for humans and those widely used in livestock have major safety concerns. A 'One Health' vaccine development approach, in which the same vaccine is co-developed for multiple susceptible species, is an attractive strategy for RVFV. Here, we utilized a replication-deficient chimpanzee adenovirus vaccine platform with an established human and livestock safety profile, ChAdOx1, to develop a vaccine for use against RVFV in both livestock and humans. We show that single-dose immunization with ChAdOx1-GnGc vaccine, encoding RVFV envelope glycoproteins, elicits high-titre RVFV-neutralizing antibody and provides solid protection against RVFV challenge in the most susceptible natural target species of the virus-sheep, goats and cattle. In addition we demonstrate induction of RVFV-neutralizing antibody by ChAdOx1-GnGc vaccination in dromedary camels, further illustrating the potency of replication-deficient chimpanzee adenovirus vaccine platforms. Thus, ChAdOx1-GnGc warrants evaluation in human clinical trials and could potentially address the unmet human and livestock vaccine needs

Safety and immunogenicity of varied doses of R21/Matrix-M™ vaccine at three years follow-up: A phase 1b age de-escalation, dose-escalation trial in adults, children, and infants in Kilifi-Kenya

BackgroundFalciparum malaria remains a global health problem. Two vaccines, based on the circumsporozoite antigen, are available. RTS, S/AS01 was recommended for use in 2021 following the advice of the World Health Organisation (WHO) Strategic Advisory Group of Experts (SAGE) on Immunization and WHO Malaria Policy Advisory Group (MPAG). It has since been pre-qualified in 2022 by the WHO. R21 is similar to RTS, S/AS01, and recently licensed in Nigeria, Ghana and Burkina Faso following Phase 3 trial results.MethodsWe conducted a Phase 1b age de-escalation, dose escalation bridging study after a change in the manufacturing process for R21. We recruited healthy adults and children and used a three dose primary vaccination series with a booster dose at 1-2 years. Variable doses of R21 and adjuvant (Matrix-M ™) were administered at 10µgR21/50 µg Matrix-M™, 5µgR21/25µg Matrix-M™ and 5µgR21/50µg Matrix-M™ to 20 adults, 20 children, and 51 infants.ResultsSelf-limiting adverse events were reported relating to the injection site and mild systemic symptoms. Two serious adverse events were reported, neither linked to vaccination. High levels of IgG antibodies to the circumsporozoite antigen were induced, and geometric mean titres in infants, the target group, were 1.1 (0.9 to 1.3) EU/mL at day 0, 10175 (7724 to 13404) EU/mL at day 84 and (following a booster dose at day 421) 6792 (5310 to 8687) EU/mL at day 456.ConclusionR21/Matrix-M™ is safe, and immunogenic when given at varied doses with the peak immune response seen in infants 28 days after a three dose primary vaccination series given four weeks apart. Antibody responses were restored 28 days after a 4 th dose given one year post a three dose primary series in the young children and infants.RegistrationClinicaltrials.gov (NCT03580824; 9 th of July 2018; Pan African Clinical Trials Registry (PACTR202105682956280; 17 th May 2021)