A flock of 54 wk-old layer birds exhibiting signs of respiratory distress, greenish diarrhea, and drop in egg production was investigated. A marked drop in egg production (55%) was recorded with eggs ...appearing white and soft-shelled. Mortality was in the range of 1%-2% with post-mortem lesions revealing cloudy air sacs, frothy, and congested lungs. Viral RNA was extracted from pooled tissue samples (trachea, lungs, spleen, and liver) and tested for Avian influenza virus (AIV), Newcastle disease virus (NDV), and infectious bronchitis virus (IBV) by reverse transcriptase-polymerase chain reaction (RT-PCR). In addition, virus isolation was attempted in 9-11 day-old embryonating chicken eggs (ECE). In order to determine the prevalence of IBV serotype(s) in the flock, serum samples were screened by hemagglutination-inhibition (HI) test using IBV antigens and antisera (Arkansas, Connecticut, and Massachusetts). Neither AIV nor NDV but IBV was detected in the tissue samples by RT-PCR. In addition, virus isolate obtained after four serial passages in ECE produced dwarfed, stunted, and hemorrhagic embryos, and the isolate was confirmed by RT-PCR to be IBV. The serum samples were 100% seropositive for three serotypes with HI titres ranging from 5 to 12 Log
. In this study, IBV was confirmed as the causative agent of the observed respiratory distress and drop in egg production. Also, the evidence of co-circulation of multiple IBV serotypes was established, this to the best of our knowledge is the first of such report in Nigeria. We recommend extensive molecular and sero-epidemiology of circulating IBV genotypes and serotypes in Nigeria with the aim of developing better control strategies, including vaccination.
Global perception and consciousness of the threat of bioterrorism seem to have diminished in recent past following achievements in decades of global fight against deadly infectious diseases such as ...plague and smallpox. However, with recent advancement in biotechnology and the arrival on the scene of amoral and rogue states as well as terrorist groups, there is a justifiably heightened global apprehension that bacteria, viruses, and toxicogenic fungi can be weaponized and used to cause great harm to humans and agricultural biodiversity. We now have on our hands the dilemma of dual-use of biotechnology. This review brings to the fore an aspect of microbial forensics – bioagent source-tracing (attribution) that is very key in mounting an appropriate response to the evident threat of bioterrorism. This article places a little more emphasis on the bioagent Yersinia pestis, and the technique of whole-genome sequence typing adjudged the most effective technique for building databases for bioterrorism-associated agents and public health important pathogens. The need for international sharing of data and databases of bio-agents is emphasized, as this would enable global applicability of bio-agent source-tracing in cases of bioterrorism.
Background
The introduction of multiple avian influenza virus (AIV) subtypes into Nigeria has resulted in several poultry outbreaks purportedly linked to trade and wild birds. The role of wild birds ...in perpetuating AIV in Nigeria was, therefore, elucidated.
Methods
A cross‐sectional study was conducted among wild aquatic bird species at the Hadejia‐Nguru wetlands in Northeastern Nigeria between March and April 2022. A total of 452 swabs (226 cloacae and 226 oropharyngeal) were collected using a mist net to capture the birds. These samples were tested by RT‐qPCR, followed by sequencing.
Results
Highly pathogenic AIV of the H5N1 subtype was identified in clinically healthy wild bird species, namely, African jacana, ruff, spur‐winged goose, squared‐tailed nightjar, white‐faced whistling ducks, and white stork. A prevalence of 11.1% (25/226) was recorded. Phylogenetic analysis of the complete HA gene segment indicated the presence of clade 2.3.4.4b. However, these H5N1 viruses characterized from these wild birds cluster separately from the H5N1 viruses characterized in Nigerian poultry since early 2021. Specifically, the viruses form two distinct genetic groups both linked with the Eurasian H5N1 gene pool but likely resulting from two distinct introductions of the virus in the region. Whole‐genome characterization of the viruses reveals the presence of mammalian adaptive marker E627K in two Afro‐tropical resident aquatic ducks. This has zoonotic potential.
Conclusion
Our findings highlight the key role of surveillance in wild birds to monitor the diversity of viruses in this area, provide the foundations of epidemiological understanding, and facilitate risk assessment.
Bioterrorism agents are mostly microorganisms with the capacity to deal explosive and lethal harm to humans, animals, and food crops. These microorganisms spread in the form of gases, whole ...organisms, or products of secondary metabolism of microorganisms. Classification of the agents is into three categories based on the ease of dissemination and end effects on a living population. While most health institutions are equipped to take care of sick people and treat suspected cases of infections, these institutions lack basic means of identifying bioterrorism acts. Special diagnostic equipment to identify causal organisms or agents is not available. Lack of training on what to do when terrorists strike using biological agents can cumulatively increase the lethal effects of such agents. Molecular techniques of identifying microorganisms to species level are as promising as they are time-consuming, while technical expertise and a conducive environment for managing such equipment are mostly not available in the African setting. The governments in Africa as a matter of urgency should provide an atmosphere where the teaming population of people without jobs are employed, while hospitals are adequately equipped, and training of health workers on what to do immediately after cases of terrorism are reported. The review highlights these agents and the diagnostic tools necessary to facilitate early response to bioterrorism.
Among recurrent sanitary emergencies able to spread rapidly worldwide, avian influenza is one of the main constraints for animal health and food security. In West Africa, Nigeria has been ...experiencing repeated outbreaks of different strains of avian influenza virus (AIV) since 2006 and is also recognized as a hot spot in the region for the introduction of emerging strains by migratory wild birds. Here, we generated complete genomes of 20 highly pathogenic avian influenza (HPAI) H5N8 viruses collected during active surveillance in Nigerian live bird markets (LBM) and from outbreaks reported in the country between 2016 and 2019. Phylogenetic analysis reveals that the Nigerian viruses cluster into four separate genetic groups within HPAI H5 clade 2.3.4.4b. The first group includes 2016–2017 Nigerian viruses with high genetic similarity to H5N8 viruses detected in Central African countries, while the second includes Nigerian viruses collected both in LBM and poultry farms (2018–2019), as well as in Cameroon, Egypt and Siberia. A natural reassortant strain identified in 2019 represents the third group: H5N8 viruses with the same gene constellation were identified in 2018 in South Africa. Finally, the fourth introduction represents the first detection in the African continent of the H5N6 subtype, which is related to European viruses. Bayesian phylogeographic analyses confirmed that the four introductions originated from different sources and provide evidence of the virus spread within Nigeria, as well as diffusion beyond its borders. The multiple epidemiological links between Nigeria, Central and Southern African countries highlight the need for harmonized and coordinated surveillance system to control AIV impact. Improved surveillance at the Wetlands, LBMs and early warning of outbreaks are crucial for prevention and control of AIV, which can be potentially zoonotic and be a threat to human health.
Four Newcastle disease virus isolates were recovered from asymptomatic guinea fowl (
Numida meleagris galeata
) and Muscovy ducks (
Cariana moscata
). For the purpose of molecular identification and ...phylogeny, phylogenetic characterization was performed to identify the pathotypes. All four viruses had a cleavage motif
112
RRQKRF
117
which is characteristic of virulent strains. The isolates grouped with viruses previously reported as sub-lineage 5g from chickens in Nigeria. This study report for the first time the identification of the virulent sub-lineage 5g Newcastle disease virus from apparently healthy guinea fowl and domestic ducks in Nigeria, and since infections were sub-clinical, it suggest that these species could play a role in the spread and transmission of virulent Newcastle disease virus that can infect other poultry. The isolation and identification of virulent Newcastle disease virus in these unusual hosts and the high sequence similarity (99.3–100 %) between viruses in this study with strains reported for Niger and Cameroun gives insights into the ecology of virulent Newcastle disease viruses and suggests some cross-border movement and trade in live poultry.
This study investigated the physical, chemical, and sensory attributes of breads produced from preheated high‐quality cassava flour (PCF) and its composite with wheat flour (CWF). Wet gluten was ...added to the PCF and CWF for production of bread, while bread from wheat served as the control. Flour functionality was determined prior to bread production. The moisture contents of the flour samples were in the range of 12.80 to 14.21%, and PCF exhibited water absorption capacity (1.12 mL/g) comparable to that of wheat flour (WF) (1.10 mL/g). There were significant (P < 0.05) differences in color characteristics, except in L* values and breads produced from WF and CWF were similar in specific volume (3.85 to 4.21 mL/g) and firmness (2.04 to 2.64 N). Breads from WF and CWF exhibited similar crumb microstructure, though gas bubbles in the sample from PCF appeared less developed. Wheat bread had significantly (P < 0.05) higher calorie, crude protein and crude fat, but lower crude fiber, ash, and carbohydrate compared to other bread samples. Sensory evaluation showed that bread from PCF was not significantly different from 100% wheat bread in crust color, texture, and overall acceptability but was impaired in flavor. The study revealed the feasibility of bread baking from preheated cassava flour with added gluten extract. The bread produced had some quality attributes comparable to that of wheat bread.
Practical Application
Bread from wheat‐cassava composite flour with added gluten was similar to wheat bread in specific volume and firmness while sample from cassava flour with added gluten compared favorably well with wheat bread in crust color, texture, and overall acceptability. Findings from the study present wheat gluten extract as a viable component to be used in nonwheat flours for bread making. This could be a basis to further add value to the gluten churned out as a by‐product in the wheat starch industry.
This work studies the cost benefits derivable from network reconfiguration and shunt compensation of a Nigerian 33 kV distribution network. The approach adopted requires that the base case power flow ...analysis of the distribution network was first carried out, after which a shunt capacitor was used for compensation. The introduction of a tie-line in the network and a combination of capacitor and tie-line on same network were also carried out. The costs analysis of compensation and reconfiguration was carried out to understand their financial worthiness. The results obtained showed that the payback period (PP) for the introduction of compensation only, reconfiguration only and combination of compensation and reconfiguration are 1286.89 hr, 328.58 hr and 1043.31 hr, respectively. Though, reconfiguration only gives the least PP, a combination of compensation and reconfiguration has a long time cost benefit. At time above 5147.57 hr, it generates more profit than others.
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