Inoculation Rate Research Articles

An Analysis of Inoculation Rates Utilizing Statistical Learning to Validate the Significance of Predictors

In a previous study, data analyzed from measuring cell phone signal movement showed that the most predictive factors of social distancing in response to the SARS-CoV-2 (COVID-19) pandemic were income and population. While a great deal of factors could be investigated to determine what the most predictive factors of inoculation rates are, this study is a continuation of the previous work by Smith, Boquet, and Chin (2020) and investigates if there is a significant difference between inoculation rates when separated by median income and population. Data is drawn from the State of Florida counties to remain consistent with the preceding work. The two-sample t-test performed revealed that there was a significant difference between the inoculation rates of counties with a high population when compared to those with a low population. A similar result was found for the inoculation rates of counties with high a median income when compared to those with a low median income. These results demonstrated that median county income and county population had impacts on both inoculation rates and social distancing.

Same Pandemic Yet Different COVID-19 Vaccination Roll-Out Rates in Two Small European Islands: A Comparison between Cyprus and Malta.

A mass vaccination strategy is estimated to be the long-term solution to control COVID-19. Different European countries have committed to vaccination strategies with variable population inoculation rates. We sought to investigate the extent to which the COVID-19 vaccination strategies, inoculation rate, and COVID-19 outcome differ between Cyprus and Malta. Data were obtained from the Ministry of Health websites and COVID-19 dashboards, while vaccination data were obtained from the European Centre for Disease Prevention and Control until mid-June, 2021. Comparative assessments were performed between the two countries using Microsoft® Excel for Mac, Version 16.54. Both islands took part in the European Union’s advanced purchase agreement and received their first batch of vaccines on 27 December 2020. The positivity rate and mortality between December and June differs between the two countries (average positivity rate Cyprus 1.34, Malta 3.37 p ≤ 0.01; average mortality Cyprus 7.29, Malta 9.68 p ≤ 0.01). Both the positivity rate and mortality for Cyprus declined due to strict public health measures and vaccination roll-out in early January (positivity rate by 95% and mortality by 58%). In contrast, for Malta, there was a sharp increase (64% p ≤ 0.01) with almost no public health restrictions in place and soaring cases during the Christmas and Carnival period until March, when lockdown measures were re-introduced. A distinctive difference between Cyprus and Malta in positivity rate (14 per 100,000 population; p ≤ 0.01) can also be observed between January and mid-April 2021. However, from April onwards it is evident that the positivity rate and mortality decline (positivity rate Cyprus by 82%, Malta by 95%; mortality Cyprus by 90%, Malta by 95%, p ≤ 0.01, respectively) in both countries as the vaccination roll-outs progressed, covering about 58.93% of the Maltese population, while Cyprus had fully inoculated about 38.03% of its population. The vaccine strategies and vaccination rates were similar for both countries; yet Malta had the fastest vaccine roll-out. Reluctancy to get vaccinated, significant differences in the vaccination appointment scheduling system, and the freedom of vaccination choice for the citizens in Cyprus may have contributed to a delayed vaccination roll-out. These potential contributing factors should be acknowledged and considered for future vaccination programs and potential COVID-19 boosters.

Plasmodium falciparum genomic surveillance reveals spatial and temporal trends, association of genetic and physical distance, and household clustering

Molecular epidemiology using genomic data can help identify relationships between malaria parasite population structure, malaria transmission intensity, and ultimately help generate actionable data to assess the effectiveness of malaria control strategies. Genomic data, coupled with geographic information systems data, can further identify clusters or hotspots of malaria transmission, parasite genetic and spatial connectivity, and parasite movement by human or mosquito mobility over time and space. In this study, we performed longitudinal genomic surveillance in a cohort of 70 participants over four years from different neighborhoods and households in Thiès, Senegal—a region of exceptionally low malaria transmission (entomological inoculation rate less than 1). Genetic identity (identity by state, IBS) was established using a 24-single nucleotide polymorphism molecular barcode, identity by descent was calculated from whole genome sequence data, and a hierarchical Bayesian regression model was used to establish genetic and spatial relationships. Our results show clustering of genetically similar parasites within households and a decline in genetic similarity of parasites with increasing distance. One household showed extremely high diversity and warrants further investigation as to the source of these diverse genetic types. This study illustrates the utility of genomic data with traditional epidemiological approaches for surveillance and detection of trends and patterns in malaria transmission not only by neighborhood but also by household. This approach can be implemented regionally and countrywide to strengthen and support malaria control and elimination efforts.

Indoor residual spraying for preventing malaria in communities using insecticide-treated nets.

Indoor residual spraying for preventing malaria in communities using insecticide-treated nets.

Field evaluation and future applications of the world's first malaria vaccine

This paper describes the safety, efficacy and operability of the world's first malaria vaccine (RTS, S/AS01) in latest field pilot studies and the recommendations from the WHO expert group for its use. In addition, further studies to examine the associations of inoculation rate and full-dose rate with the reduction in morbidity and mortality of malaria among target children and explore the scientific evidence for seasonable preventive vaccination with 5 doses and more among children at ages of below 5 years are recommended.

不同水分处理下双接种丛枝菌根真菌和根瘤菌对疏叶骆驼刺生长及氮素转移的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 不同水分处理下双接种丛枝菌根真菌和根瘤菌对疏叶骆驼刺生长及氮素转移的影响 DOI: 10.5846/stxb202105181301 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（42067067）；新疆维吾尔自治区自然科学基金项目（2020D01A74） Effects of double inoculation with arbuscular mycorrhizal fungi and rhizobia under different water treatments on growth and nitrogen transfer of Alhagi sparsifolia Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:以疏叶骆驼刺为研究对象，设定3个水分梯度正常水分（土壤相对含水量（70±5）%）、干旱胁迫（土壤相对含水量（20±5）%）和复水处理（干旱胁迫60天后恢复至正常水分）与四组接种处理（单接种丛枝菌根真菌（AMF）、单接种根瘤菌、双接种AMF+根瘤菌和不接种），分析不同水分条件下双接种丛枝菌根真菌和根瘤菌对疏叶骆驼刺的生长以及供、受体疏叶骆驼刺之间氮素转移的影响。结果表明，正常水分处理时，双接种疏叶骆驼刺的AMF侵染率、地上生物量、地下生物量、总生物量以及氮含量均要高于单接种处理；根瘤数量、最大荧光（Fm）、初始荧光（Fo）、最大光化学效率（Fv/Fm）与单接种处理之间无差异；在遭遇干旱胁迫时，双接种疏叶骆驼刺的AMF侵染率、总生物量、Fv/Fm均小于单接种处理；地上生物量、地下生物量、根瘤数、Fm、Fo以及氮含量与单接种之间无差异。复水后，双接种疏叶骆驼刺的地上生物量、地下生物量、总生物量、根瘤数均优于单接种；AMF侵染率、氮含量低于单接种；Fm、Fo、Fv/Fm均与单接种之间无差异。在氮素转移方面，正常水分时，双接种与单接种的氮素转移率无差异，在遭遇干旱胁迫时，双接种疏叶骆驼刺的氮素转移率显著降低，即使复水后，仍得不到恢复。可见，与单接种AMF或单接种根瘤菌相比，双接种AMF和根瘤菌在正常水分时更具有优势，干旱胁迫会导致AMF和根瘤菌协同促生优势的减弱，复水后双接种疏叶骆驼刺能及早的对水分变化做出响应，对其生长具有一定的补偿作用，但仍不能抵消干旱胁迫所带来的损伤。丛枝菌根网络促进氮素转移一定程度上提高了疏叶骆驼刺幼苗耐旱性，但是在干旱条件下双接种疏叶骆驼刺的氮素转移率要低于单接种AMF，复水后仍得不到恢复。 Abstract:In this study, three water gradients and four inoculation treatments were established to analyze the effects of a double inoculation of arbuscular mycorrhizal fungi (AMF) and rhizobia on the growth of Alhagi sparsifolia and nitrogen between the donor and recipient plants. The water gradient included normal water (soil relative water content (70±5)%), drought stress (soil relative water content (20±5)%) and rewatered treatment (return to the water content after 60 days of drought stress). The plants were inoculated singly with AMF or rhizobia. In addition, other plants were inoculated with both organisms (double AMF+rhizobia inoculation), and there was a control of no inoculation. The infection rate of AMF, the aboveground, belowground total biomass and the nitrogen content of double inoculation treatment was higher than that of the single inoculation when there was a normal amount of water. The nodule number, Fm, Fo and Fv/Fm did not differ from those of the single inoculation treatment. However, the AMF infection rate, total biomass and Fv/Fm rate of the double inoculation treatment were all lower than those of single inoculation under drought stress. There was no difference in the aboveground and belowground biomass, nodule number, Fm, Fo and nitrogen content compared with the single inoculation under drought stress. After rehydration, the aboveground, belowground and total biomass and the number of nodules on A. sparsifolia that had been treated with both AMF and rhizobia were higher than those inoculated singly. The rates of infection and nitrogen content rate of AMF after rehydration were lower than those that followed a single inoculation. The values of Fm, Fo, Fv/Fm did not differ from those of the single inoculation. An analysis of the amount of nitrogen transfer indicated that there was no difference between double and single inoculation under normal water conditions. However, the growth of A. sparsifolia that had been double inoculated decreased significantly under drought stress and could not be restored even after rehydration. It was apparent that the double inoculation of AMF and rhizobia compared with their single inoculation provides more benefits when the water content is normal and that drought stress will weaken the ability of AMF and rhizobia to synergistically enhance plant growth. After rehydration, A.sparsifolia that had been treated with both species quickly responded to changes in the water content. This ability can somewhat compensate for the effects of drought stress. However, it still cannot offset the damage. Arbuscular mycorrhizal network promoted nitrogen transfer and increased drought tolerance of A. sparsifoliaseedlings to a certain extent. However, the nitrogen transfer rate of double inoculation was lower than that of the single inoculation of AMF under drought conditions, which could not be reversed after rehydration. 参考文献 相似文献 引证文献

Larval flushing alters malaria endemicity patterns in regions with similar habitat abundance

A model of Anopheles gambiae populations dynamics coupled with Plasmodium falciparum transmission dynamics is extended to include mechanisms of larval flushing which are known to occur. Flushing dynamics are modeled using a simulation that incorporates seasonal, autocorrelated, and random components based on 30 years of rainfall data for the Kakamega District of the western Kenya highlands. The model demonstrates that flushing phenomena can account for differences between regions with the same annual larval habitat pattern, changing the World Health Organization endemicity classification from either hyperendemic or holoendemic to hypoendemic disease patterns. Mesoendemic patterns of infection occur at the boundary of the holoendemic to hypoendemic transition. For some levels of flushing the entomological inoculation rate drops to an insignificant amount and disease disappears, while the annual indoor resting density remains well above zero. In these scenarios, the disease is hypoendemic, yet the model shows that outbreaks can occur when disease is introduced at particular time points.

High vectorial transmission of malaria in urban and rural settings in the northern, western and eastern regions of Côte d'Ivoire.

Malaria remains a public health problem in Côte d'Ivoire. To cope with this issue, the Ministry of Health established strategies through Long-Lasting Insecticidal Nets (LLINs) and artemisinin-based medicines. To better understand the influence of periodic mass distribution of LLINs on malaria transmission, this entomological survey was conducted in three regions of Côte d'Ivoire. Mosquitoes were sampled by Human Landing Catches (HLC) in urban and rural settings of Korhogo, Man and Abengourou. Mosquitoes were identified morphologically and by molecular methods. Plasmodium falciparum infection was assessed by ELISA, and the Entomological Inoculation Rates (EIR) were calculated for each species and setting. Only An. gambiae s.l. was identified in Korhogo and in Abengourou while An. gambiae s.l. and An. funestus s.l. was reported in Man. An. coluzzii was the most abundant species of the An. gambiae siblings collected in Abengourou, and in Man while An. gambiae was most abundant in Korhogo. In urban settings, malaria vectors showed high aggressiveness (>11 bites per person per night) and the annual EIR was high (83.22-438.44 infectious bites per person per year). In rural settings, malaria vectors showed also high aggressiveness (19-52 b/p/n). The annual EIR is very high (>94 ib/p/yr). However, the weakest EIR was recorded in the northern region with 94.90 ib/p/yr. This work indicates that malaria transmission remains high and heterogeneous across Côte d'Ivoire, despite repeated mass distribution of LLINs. Also, in Man, malaria transmission is more intense with the involvement of two main vectors. Furthermore, in the village of Korhogo, the EIR remained relatively low.

Epidemiological and ecological consequences of virus manipulation of host and vector in plant virus transmission.

Many plant viruses are transmitted by insect vectors. Transmission can be described as persistent or non-persistent depending on rates of acquisition, retention, and inoculation of virus. Much experimental evidence has accumulated indicating vectors can prefer to settle and/or feed on infected versus noninfected host plants. For persistent transmission, vector preference can also be conditional, depending on the vector's own infection status. Since viruses can alter host plant quality as a resource for feeding, infection potentially also affects vector population dynamics. Here we use mathematical modelling to develop a theoretical framework addressing the effects of vector preferences for landing, settling and feeding-as well as potential effects of infection on vector population density-on plant virus epidemics. We explore the consequences of preferences that depend on the host (infected or healthy) and vector (viruliferous or nonviruliferous) phenotypes, and how this is affected by the form of transmission, persistent or non-persistent. We show how different components of vector preference have characteristic effects on both the basic reproduction number and the final incidence of disease. We also show how vector preference can induce bistability, in which the virus is able to persist even when it cannot invade from very low densities. Feedbacks between plant infection status, vector population dynamics and virus transmission potentially lead to very complex dynamics, including sustained oscillations. Our work is supported by an interactive interface https://plantdiseasevectorpreference.herokuapp.com/. Our model reiterates the importance of coupling virus infection to vector behaviour, life history and population dynamics to fully understand plant virus epidemics.

Anopheles salivary antigens as serological biomarkers of vector exposure and malaria transmission: A systematic review with multilevel modelling.

Entomological surveillance for malaria is inherently resource-intensive and produces crude population-level measures of vector exposure which are insensitive in low-transmission settings. Antibodies against Anopheles salivary proteins measured at the individual level may serve as proxy biomarkers for vector exposure and malaria transmission, but their relationship is yet to be quantified. A systematic review of studies measuring antibodies against Anopheles salivary antigens (PROSPERO: CRD42020185449). Multilevel modelling (to account for multiple study-specific observations [level 1], nested within study [level 2], and study nested within country [level 3]) estimated associations between seroprevalence with Anopheles human biting rate (HBR) and malaria transmission measures. From 3981 studies identified in literature searches, 42 studies across 16 countries were included contributing 393 study-specific observations of anti-Anopheles salivary antibodies determined in 42,764 samples. A positive association between HBR (log transformed) and seroprevalence was found; overall a twofold (100% relative) increase in HBR was associated with a 23% increase in odds of seropositivity (OR: 1.23, 95% CI: 1.10-1.37; p<0.001). The association between HBR and Anopheles salivary antibodies was strongest with concordant, rather than discordant, Anopheles species. Seroprevalence was also significantly positively associated with established epidemiological measures of malaria transmission: entomological inoculation rate, Plasmodium spp. prevalence, and malarial endemicity class. Anopheles salivary antibody biomarkers can serve as a proxy measure for HBR and malaria transmission, and could monitor malaria receptivity of a population to sustain malaria transmission. Validation of Anopheles species-specific biomarkers is important given the global heterogeneity in the distribution of Anopheles species. Salivary biomarkers have the potential to transform surveillance by replacing impractical, inaccurate entomological investigations, especially in areas progressing towards malaria elimination. Australian National Health and Medical Research Council, Wellcome Trust.

Assessing nutritional status and development of Pereskia aculeata Mill. affected by inoculation of Azospirillum brasilense combined with nitrogen rates

The interactive effect of Azospirillum brasilense inoculation and nitrogen (N) rates on Ora-pro-nobis (Pereskia aculeata Mill.) is poorly understood. Ora-pro-nobis (OPN) could be an important horticultural plant to promote a diverse and healthy diet to combat macronutrients and micronutrients deficiencies, particularly in developing countries. The objectives of this research were to assess the effect of inoculation with A. brasilense combined with N rates on OPN development, yield and leaf nutrients content under greenhouse conditions. Treatments were tested in a randomized completely block design with four replicates, arranged in a full factorial design 2 × 5 and included: i) two inoculations (with and without A. brasilense) and iii) five N application rates (0, 50, 100, 150 and 200 kg ha−1 applied in two split application as ammonium sulfate source). Inoculation with A. brasilense benefited OPN growth and development, leading to a greater leaf biomass, even combined or not with N application rates. In addition, A. brasilense inoculation increased OPN nutrition with increased leaf N, P, K, Ca, Mg, S, Fe and Zn concentrations. Azospirillum brasilense combined with 150 kg N ha−1 increased leaf biomass by 40% in sampling 1, and in sampling 2, A. brasilense inoculation increased leaf biomass by 8.8% regardless N application rates. Therefore, A. brasilense inoculation could be an important practice to increase OPN cultivation, development, nutrition and yield. Ora-pro-nobis showed high nutrient content in leaf tissue, therefore, OPN plant can be an interesting source of nutrients to human consumption. Nitrogen application rates benefited OPN growth and development leading to a greater leaf biomass. In addition, N application rates increased OPN nutrition with increased leaf N, P, Ca, Mg, S, Cu, Mn and Zn concentrations. However, increasing N rates decreased leaf K concentration. Therefore, long-term studies are required to better understand the role of A. brasilense under different N management and their effects on OPN development and nutritional properties, aiming to reduce N application rates and improve N management in OPN cultivation.

A systematic review to understand the value of entomological endpoints for assessing the efficacy of vector control interventions

To guide implementation of vector control interventions in Europe, a stronger evidence base of their efficacy and effectiveness is needed. Currently, epidemiological endpoints are used to demonstrate the public health value of a vector control intervention. This systematic literature review aimed to help assess whether entomological endpoints (such as mosquito abundance, infection rates, inoculation rates, parity rate as proxy for longevity, or others) can be used on their own as evidence of efficacy of vector control interventions against vector-borne diseases. We searched electronic bibliographic databases (The Cochrane Library, CAB Abstracts, MEDLINE and Web of Science) for intervention trials where vector control interventions were evaluated and extracted epidemiological and entomological effect size estimates. The selection process resulted in 31 studies (extracted from 35 publications) for which both types of endpoints were available. The final database included studies on malaria (n=16), dengue (n=9), leishmaniasis (n=5) and tick-borne diseases (n=1). Epidemiological and entomological effect sizes often pointed in the same direction (i.e. both favouring intervention or favouring control). However, based on the statistical inference (whether the effect size estimate is significantly different from no-effect) of the results, we observed some disagreement between endpoints, though we rarely saw complete disagreement in effect estimates. This review illustrates the complex relation between entomological and epidemiological endpoints. Based on this review, it is concluded that evaluating interventions on entomological endpoints only is insufficient to understand their potential epidemiological impact. To better asses the value of entomological endpoints for the assessment of efficacy of vector control intervention, there is a need for studies to be powered for both epidemiological and entomological endpoints.

How many begomovirus copies are acquired and inoculated by its vector, whitefly (Bemisia tabaci) during feeding?

Begomoviruses are transmitted by whitefly (Bemisia tabaci Gennadius, Hemiptera: Aleyrodidae) in a persistent-circulative way. Once B. tabaci becomes viruliferous, it remains so throughout its life span. Not much is known about the copies of begomoviruses ingested and/or released by B. tabaci during the process of feeding. The present study reports the absolute quantification of two different begomoviruses viz. tomato leaf curl New Delhi virus (ToLCNDV, bipartite) and chilli leaf curl virus (ChiLCV, monopartite) at different exposure of active acquisition and inoculation feeding using a detached leaf assay. A million copies of both the begomoviruses were acquired by a single B. tabaci with only 5 min of active feeding and virus copy number increased in a logarithmic model with feeding exposure. Whereas, a single B. tabaci could inoculate 8.21E+09 and 4.19E+11 copies of ToLCNDV and ChiLCV, respectively in detached leaves by 5 min of active feeding. Virus copies in inoculated leaves increased with an increase in feeding duration. Comparative dynamics of these two begomoviruses indicated that B. tabaci adult acquired around 14-fold higher copies of ChiLCV than ToLCNDV 24 hrs post feeding. Whereas, the rate of inoculation of ToLCNDV by individual B. tabaci was significantly higher than ChiLCV. The study provides a better understanding of begomovirus acquisition and inoculation dynamics by individual B. tabaci and would facilitate research on virus-vector epidemiology and screening host resistance.

The effect of a mass distribution of insecticide-treated nets on insecticide resistance and entomological inoculation rates of Anopheles gambiae s.l. in Bandundu City, Democratic Repub`lic of Congo.

Introductioninsecticide-treated nets (ITNs) remain the mainstay of malaria vector control in the Democratic Republic of Congo. However, insecticide resistance of malaria vectors threatens their effectiveness. Entomological inoculation rates and insecticide susceptibility in Anopheles gambiae s.l. were evaluated before and after mass distribution of ITNs in Bandundu City for possible occurrence of resistance.Methodsa cross-sectional study was conducted from 15th July 2015 to 15th June 2016. Adult mosquitoes were collected using pyrethrum spray catches and human landing catches and identified to species level and tested for the presence of sporozoites. Bioassays were carried out before and after distribution of ITNs to assess the susceptibility of adult mosquitoes to insecticides. Synergist bioassays were also conducted and target site mutations assessed using Polymerase chain reaction (PCR).Resultsa total of 1754 female An. gambiae s.l. were collected before and after deployment of ITNs. Fewer mosquitoes were collected after the distribution of ITNs. However, there was no significant difference in sporozoite rates or the overall entomological inoculation rate before and after the distribution of ITNs. Test-mosquitoes were resistant to deltamethrin, permethrin, and Dichlorodiphenyltrichloroethane but susceptible to bendiocarb. Pre-exposure of mosquitoes to Piperonyl butoxide increased their mortality after exposure to permethrin and deltamethrin. The frequency of the Kinase insert domain receptor (kdr)-West gene increased from 92 to 99% before and after the distribution of nets, respectively.Conclusionseasonal impacts could be a limiting factor in the analysis of these data; however, the lack of decrease in transmission after the distribution of new nets could be explained by the high-level of resistance to pyrethroid.

Identifying Plasmodium falciparum transmission patterns through parasite prevalence and entomological inoculation rate

Monitoring malaria transmission is a critical component of efforts to achieve targets for elimination and eradication. Two commonly monitored metrics of transmission intensity are parasite prevalence (PR) and the entomological inoculation rate (EIR). Comparing the spatial and temporal variations in the PR and EIR of a given geographical region and modelling the relationship between the two metrics may provide a fuller picture of the malaria epidemiology of the region to inform control activities. Using geostatistical methods, we compare the spatial and temporal patterns of Plasmodium falciparum EIR and PR using data collected over 38 months in a rural area of Malawi. We then quantify the relationship between EIR and PR by using empirical and mechanistic statistical models. Hotspots identified through the EIR and PR partly overlapped during high transmission seasons but not during low transmission seasons. The estimated relationship showed a 1-month delayed effect of EIR on PR such that at lower levels of EIR, increases in EIR are associated with rapid rise in PR, whereas at higher levels of EIR, changes in EIR do not translate into notable changes in PR. Our study emphasises the need for integrated malaria control strategies that combine vector and human host managements monitored by both entomological and parasitaemia indices. This work was supported by Stichting Dioraphte grant number 13050800.

Exploring potentials of antioxidative, anti-inflammatory activities and production of bioactive peptides in lactic fermented camel milk

Camel milk has nutritional and medicinal benefits for the human hosts. The antioxidant activities (ABTS assay, superoxide and hydroxyl free radical assay) in camel milk fermented with Lactobacillus plantarum KGL3A were evaluated. At 48 h (37 °C), the superoxide scavenging activity of free radicals (52.26%), ABTS (62.19%), and hydroxyl scavenging activity of free radicals (61.52%) were measured. The optimal growth conditions for maximal peptide development via proteolytic activity (OPA method) (inoculation rate and incubation time) were determined, and the highest peptide (7.84 mg/ml) was reported at 37 °C for 48 h. Lower molecular weight fermented camel milk peptides decreased the production of proinflammatory cytokines by the lipopolysaccharide treated murine macrophages. Protein profiles had been examined using 2D and SDS-PAGE with a water-soluble extract from fermented camel milk. All 2D spots were trypsin digested and analyzed in RPLC/MS. RP-HPLC was used to analyze 3 kDa and 10 kDa permeates, and RPLC/MS was used to detect peptides. Peakview analysts' tools were used to calculate the raw masses of LC/MS. Most of the new peptides in the Swissport and PIR databases were derived from fermented camel milk protein sequences. Searches in the BIOPEP database confirmed the new antioxidant peptides.

Production and characterization of antioxidative peptides during lactic fermentation of goat milk

In the study, Lactobacillus fermentum M2 was characterized with potent antioxidative properties viz. ABTS assay (57.09%), HFRSA (57.30%), and SFRSA (51.40%) after 48 hr at 37°C in fermented goat milk. Further, the inoculation rate (2%) and incubation time (48 hr) for the production of peptides were also optimized using proteolytic activity at 37°C during the fermentation of goat milk. The molecular weight of proteins was analyzed by SDS-PAGE and protein bands in the range of 10–51 kDa were found. The 2D gel electrophoresis exhibited 41 protein spots between 10 and 51 kDa. The trypsin digested protein spots were injected into RPLC/MS for amino acid sequencing. The 3 and 10 kDa permeate fragments were injected into RPLC/MS for characterization of peptides, and the peptide masses from LC/MS were analyzed on MASCOT. Novel antioxidative peptides viz., SCQDQPTTLAR (2D-PAGE), TIDMESTEVFTKK (3 kDa Permeate), and YIQKEDVPSER (10 kDa Permeate) were identified from goat milk fermented with M2 by matching with BLASTp (NCBI), protein information resource (PIR), and BIOPEP databases. Practical applications Goat milk provides several health benefits, including antioxidative, antihypertensive, and antimicrobial properties. In terms of bio-functional characteristics, goat milk fermented with healthy lactic acid bacteria could even add more value. Goat milk fermented with Lactobacillus fermentum M2 exhibited promising bioactivities like hydroxyl free radical scavenging assay, superoxide free radical scavenging assay, antioxidative activity, and proteolytic activities. A few novel antioxidative peptides, viz., SCQDQPTTLAR, TIDMESTEVFTKK, and YIQKEDVPSER, were identified from goat milk fermented with M2 by similarity searches using BLASTp, PIR, and BIOPEP databases. Furthermore, L. fermentum M2 could be used for the production of fermented goat milk with antioxidative activity and bioactive peptides.

Malaria Transmission, Vector Diversity, and Insecticide Resistance at a Peri-Urban Site in the Forest Zone of Ghana

IntroductionRecent surge ofAnophelesresistance to major classes of World Health Organization (WHO)-approved insecticides globally necessitates the need for information about local malaria vector populations. It is believed that insecticide efficacy loss may lead to operational failure of control interventions and an increase in malaria infection transmission. We investigated the susceptibility levels of malaria vectors to all classes of WHO-approved vector control insecticides and described the dynamics of malaria transmission in a peri-urban setting.MethodsFit 3–5-day-old adults that emerged fromAnopheleslarvae collected from several different sites in the study area were subjected to the WHO bioassay for detecting insecticide resistance. The knockdown resistance gene (kdr) mutations within the vector populations were detected using PCR. Entomological inoculation rates were determined using the human landing catch technique andPlasmodium falciparumcircumsporozoite ELISA.ResultsThe malaria vectors from the study area were resistant to all classes of insecticides tested. Out of the 284Anophelescomplex specimen assayed for the resistance study, 265 (93.30%) were identified asAnopheles gambiae s.s.The kdr gene was detected in 90% of theAnopheles gambiae s.s.assayed. In an area whereAnopheles coluzziiresistance to insecticides had never been reported, the kdr gene was detected in 78% of theAnopheles coluzziisampled. The entomological inoculation rate (EIR) for the dry season was 1.44 ib/m/n, whereas the EIR for the rainy season was 2.69 ib/m/n.ConclusionsThis study provides information on the high parasite inoculation rate and insecticide resistance of malaria vectors in a peri-urban community, which is critical in the development of an insecticide resistance management program for the community.

A comparison of PCR and ELISA methods to detect different stages of Plasmodium vivax in Anopheles arabiensis

BackgroundIn characterizing malaria epidemiology, measuring mosquito infectiousness informs the entomological inoculation rate, an important metric of malaria transmission. PCR-based methods have been touted as more sensitive than the current “gold-standard” circumsporozoite (CSP) ELISA. Wider application of PCR-based methods has been limited by lack of specificity for the infectious sporozoite stage. We compared a PCR method for detecting the parasite’s mitochondrial (mt) cytochrome oxidase I (COX-I) gene with ELISA for detecting circumsporozoite protein for identification of different life stages of the parasite during development within a mosquito.MethodsA PCR-based method targeting the Plasmodium mt COX-I gene was compared with the CSP ELISA method to assess infectivity in Anopheles arabiensis colony mosquitoes fed on blood from patients infected with Plasmodium vivax. Mosquitoes were tested at six post-infection time points (days 0.5, 1, 6, 9, 12, 15). The head and thorax and the abdomen for each specimen were tested separately with each method. Agreement between methods at each infection stage was measured using Cohen’s kappa measure of test association.ResultsInfection status of mosquitoes was assessed in approximately 90 head/thorax and 90 abdomen segments at each time point; in total, 538 head/thorax and 534 abdomen segments were tested. In mosquitoes bisected after 0.5, 1, and 6 days post-infection (dpi), the mt COX-I PCR detected Plasmodium DNA in both the abdomen (88, 78, and 67%, respectively) and head/thorax segments (69, 60, and 44%, respectively), whilst CSP ELISA detected sporozoites in only one abdomen on day 6 post-infection. PCR was also more sensitive than ELISA for detection of Plasmodium in mosquitoes bisected after 9, 12, and 15 dpi in both the head and thorax and abdomen. There was fair agreement between methods for time points 9–15 dpi (κ = 0.312, 95% CI: 0.230–0.394).ConclusionsThe mt COX-I PCR is a highly sensitive, robust method for detecting Plasmodium DNA in mosquitoes, but its limited Plasmodium life-stage specificity cannot be overcome by bisection of the head and thorax from the abdomen prior to PCR. Thus, the mt COX-I PCR is a poor candidate for identifying infectious mosquitoes.Graphical

Partial indoor residual spraying with pirimiphos-methyl as an effective and cost-saving measure for the control of Anopheles gambiae s.l. in northern Ghana

The scale up of indoor residual spraying (IRS) and insecticide treated nets have contributed significantly to global reductions in malaria prevalence over the last two decades. However, widespread pyrethroid resistance has necessitated the use of new and more expensive insecticides for IRS. Partial IRS with pirimiphos-methyl in experimental huts and houses in a village-wide trial was evaluated against Anopheles gambiae s.l. in northern Ghana. Four different scenarios in which either only the top or bottom half of the walls of experimental huts were sprayed, with or without also spraying the ceiling were compared. Mortality of An. gambiae s.l. on partially sprayed walls was compared with the standard procedures in which all walls and ceiling surfaces are sprayed. A small-scale trial was then conducted to assess the effectiveness, feasibility, and cost of spraying only the upper walls and ceiling as compared to full IRS and no spraying in northern Ghana. Human landing catches were conducted to estimate entomological indices and determine the effectiveness of partial IRS. An established transmission dynamics model was parameterized by an analysis of the experimental hut data and used to predict the epidemiological impact and cost effectiveness of partial IRS for malaria control in northern Ghana. In the experimental huts, partial IRS of the top (IRR 0.89, p = 0.13) or bottom (IRR 0.90, p = 0.15) half of walls and the ceiling was not significantly less effective than full IRS in terms of mosquito mortality. In the village trial, the annual entomological inoculation rate was higher for the unsprayed control (217 infective bites/person/year (ib/p/yr)) compared with the fully and partially sprayed sites, with 28 and 38 ib/p/yr, respectively. The transmission model predicts that the efficacy of partial IRS against all-age prevalence of malaria after six months would be broadly equivalent to a full IRS campaign in which 40% reduction is expected relative to no spray campaign. At scale, partial IRS in northern Ghana would have resulted in a 33% cost savings ($496,426) that would enable spraying of 36,000 additional rooms. These findings suggest that partial IRS is an effective, feasible, and cost saving approach to IRS that could be adopted to sustain and expand implementation of this key malaria control intervention.