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1.
Dev Comp Immunol ; 133: 104443, 2022 08.
Article in English | MEDLINE | ID: covidwho-20241503

ABSTRACT

The COVID-19 pandemic is a wake-up call on the zoonotic viral spillover events and the need to be prepared for future outbreaks. Zoonotic RNA viruses like the Middle East respiratory syndrome coronavirus (MERS-CoV) are potential pathogens that could trigger the next pandemic. Dromedary camels are the only known animal source of MERS-CoV zoonotic infections, but little is known about the molecular antiviral response in this species. IFN-ß and other type-I interferons provide the first line of defense against invading pathogens in the host immune response. We identified the IFNB gene of the dromedary camel and all extant members of the family Camelidae. Camelid IFN-ß is unique with an even number of cysteines in the mature protein compared to other eutherian mammals with an odd number of cysteines. The viral mimetic poly(I:C) strongly induced IFN-ß expression in camel kidney cells. Induction of IFN-ß expression upon infection with camelpox virus was late and subdued when compared to poly(I:C) treatment. Prokaryotically expressed recombinant dromedary IFN-ß induced expression of IFN-responsive genes in camel kidney cells. Further, recombinant IFN-ß conferred antiviral resistance to camel kidney cells against the cytopathic effects of the camelpox virus, an endemic zoonotic pathogen. IFN-ß from this unique group of mammals will offer insights into antiviral immune mechanisms and aid in the development of specific antivirals against pathogens that have the potential to be the next zoonotic pandemic.


Subject(s)
COVID-19 , Middle East Respiratory Syndrome Coronavirus , Animals , Antiviral Agents , Camelus , Eutheria , Humans , Interferon-beta/genetics , Middle East Respiratory Syndrome Coronavirus/genetics , Pandemics , Zoonoses
2.
Emerg Microbes Infect ; 12(1): 2220577, 2023 Dec.
Article in English | MEDLINE | ID: covidwho-20235192

ABSTRACT

SARS-CoV-2 has demonstrated the ability to infect a wide range of animal species. Here, we investigated SARS-CoV-2 infection in livestock species in Oman and provided serological evidence of SARS-CoV-2 infection in cattle, sheep, goats, and dromedary camel using the surrogate virus neutralization and plaque reduction neutralization tests. To better understand the extent of SARS-CoV-2 infection in animals and associated risks, "One Health" epidemiological investigations targeting animals exposed to COVID-19 human cases should be implemented with integrated data analysis of the epidemiologically linked human and animal cases.


Subject(s)
COVID-19 , Cattle , Humans , Animals , Sheep , COVID-19/epidemiology , COVID-19/veterinary , Oman/epidemiology , Camelus , SARS-CoV-2 , Data Analysis , Goats
3.
Infektoloski Glasnik ; 42(1):9-15, 2022.
Article in English | EMBASE | ID: covidwho-2326894

ABSTRACT

Seven human coronaviruses have been identified so far: four seasonal coronaviruses (HCoV-229E, HCoV-OC43, HCoV-NL63, HCoV-HKU1) and three novel coronaviruses (SARS-CoV, MERS-CoV, SARS-CoV-2). While seasonal coronaviruses cause only mild symptoms, novel coronaviruses cause severe and potentially fatal infections. All known coronaviruses originated in animals. Bats are considered as an origin for the majority of coronaviruses capable of infecting humans;however, rodents are proposed as natural hosts for HCoV-OC43 and HCoV-HKU1. Different animal species could serve as intermediate hosts including alpacas (HCoV-229E), livestock (HCoV-OC43), civet cats (SARS-CoV), camels (MERS-CoV), and pangolins (SARS-CoV-2). In Croatia, SARS-CoV-2 was detected in humans, pet animals, wildlife, and the environment. The COVID-19 pandemic has highlighted the role of the 'One Health' approach in the surveillance of zoonotic diseases.Copyright © 2022, University Hospital of Infectious Diseases. All rights reserved.

4.
Cogent Economics and Finance ; 11(1), 2023.
Article in English | Scopus | ID: covidwho-2326532

ABSTRACT

This study aims to provide empirical evidence regarding the impact of the COVID-19 pandemic on banking performance in Indonesia. This study examines differences in Indonesian banking performance before and during the COVID-19 pandemic. Banking performance in this study was measured using the CAMEL measure. The analysis was carried out by conducting a different test using the SPSS application version 22.0. Based on the results of tests conducted on 205 observations on banking from 2018 to 2021, it was found that the CAR, ROA, ROE, BOPO, LDR, and Customer Deposit levels from banks in Indonesia had a significant difference between before and during the COVID-19 pandemic. However, there was no significant difference between the NPL banking level in Indonesia before and during the COVID-19 pandemic. This proves that the COVID-19 pandemic has harmed banking in Indonesia, so the government must pay attention to the current banking strength to survive and recover after the COVID-19 pandemic. © 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

5.
One Health ; 16: 100561, 2023 Jun.
Article in English | MEDLINE | ID: covidwho-2315604

ABSTRACT

The Middle East respiratory syndrome Coronavirus (MERS-CoV) is one of the human coronaviruses that causes severe respiratory infection. Bats are considered to be the natural reservoir, where dromedary camels (DC) are the intermediate hosts of the virus. The current study was undertaken to provide an update on global distribution of the virus in camels, and to investigate the pooled prevalence and camel-associated risk factors of infection. After registration of the review protocol in the Open Science Framework, data searches were conducted on 18 April 2023 through Embase, PubMed, Scopus, and Web of Science. Considering only natural MERS-CoV infection in camels, 94 articles were selected for data curation through blind screening by two authors. Meta-analysis was conducted to estimate the pooled prevalence and to evaluate camel-associated risk factors. Finally, the results were presented in forest plots. The reviewed articles tested 34 countries, of which camels of 24 countries were seropositive and in 15 countries they were positive by molecular method. Viral RNA was detected in DC. Non-DC, such as bactrian camels, alpaca, llama, and hybrid camels were only seropositive. The global estimated pooled seroprevalence and viral RNA prevalence in DC were 77.53% and 23.63%, respectively, with the highest prevalence in West Asia (86.04% and 32.37% respectively). In addition, 41.08% of non-DC were seropositive. The estimated pooled prevalence of MERS-CoV RNA significantly varied by sample types with the highest in oral (45.01%) and lowest in rectal (8.42%) samples; the estimated pooled prevalence in nasal (23.10%) and milk (21.21%) samples were comparable. The estimated pooled seroprevalence in <2 years, 2-5 years, and > 5 years age groups were 56.32%, 75.31%, and 86.31%, respectively, while viral RNA prevalence was 33.40%, 15.87%, and 13.74%, respectively. Seroprevalence and viral RNA prevalence were generally higher in females (75.28% and 19.70%, respectively) than in males (69.53% and 18.99%, respectively). Local camels had lower estimated pooled seroprevalence (63.34%) and viral RNA prevalence (17.78%) than those of imported camels (89.17% and 29.41%, respectively). The estimated pooled seroprevalence was higher in camels of free-herds (71.70%) than confined herds (47.77%). Furthermore, estimated pooled seroprevalence was higher in samples from livestock markets, followed by abattoirs, quarantine, and farms but viral RNA prevalence was the highest in samples from abattoirs, followed by livestock markets, quarantine, and farms. Risk factors, such as sample type, young age, female sex, imported camels, and camel management must be considered to control and prevent the spread and emergence of MERS-CoV.

6.
Health Biotechnology and Biopharma ; 4(4):6-15, 2021.
Article in English | EMBASE | ID: covidwho-2302349

ABSTRACT

The purposes of this review was in the direction of epidemiology, causative agents, symptoms, vaccine research probabilities and COVID-19 infection novel Corona viruses that was investigated in China. The COVID-19 has surrounded viruses along with a practical sensation one stranded RNA genome and a nucleocapsid of helical uniformity. The COVID-19 is an enormous family of viruses that are prevalent in a public and large number of species of animals including hens, camels, bats, cat, and cattle. Human corona viruses can cause gentle disorder identical to a common cough, cold, while others reason more acute disease MERS (Middle East Respiratory Syndrome) and SARS (Severe Acute Respiratory Syndrome). Thus spreading the COVID-19 should be closely investigated to recognize the growth of particularly virulent strains in society at an early stage and to simplify the evolution of enough preventive and therapeutic measurements.Copyright © 2021, Health Biotechnology and Biopharma. All rights reserved.

7.
Bulletin of Russian State Medical University ; 2023(1):12-20, 2023.
Article in English | EMBASE | ID: covidwho-2285740

ABSTRACT

Several COVID-19 vaccines have been developed in the last three years using various tecnhiques. Multiple virus-neutralizing antibodies against SARS-CoV-2 have been also obtained to combat the pandemic. However, the use of these medications for prevention and potential treatment faces significant challenges due to the emergence of new mutant virus variants, both more contagious and escaping neutralization by the immune system, that is why it is necessary to continuously renew the vaccines and develop new therapeutic antibodies. The study was aimed to use the technology of generating single-domain antibodies (nanobodies) to target the surface spike (S) protein RBD conserved epitope of the broad spectrum of SARS-CoV-2 variants. Recombinant proteins that corresponded to RBDs of three important SARS-SoV-2 strains and the full-length S protein (Wuhan) were used as antigens for immunization of a camel in order to induce production of appropriate antibodies and/or as immobilized proteins for further cross selection of the nanobody clones with pre-set specificity by the phage display. A nanobody capable of effectively recognizing the conservative region in the S protein RBDs of the broad spectrum of pandemic SARS-CoV-2 variants, including Omicron, was selected from the generated immune library. Along with conventional use in immunoassays and diagnosis, the generated nanobody can be potentially used as a module for target-specific binding used to trap coronavirus in human upper airways during the development of novel combination antiviral drugs.Copyright © 2023 Pirogov Russian National Research Medical University. All rights reserved.

8.
Pathogens ; 10(4)2021 Apr 01.
Article in English | MEDLINE | ID: covidwho-2247799

ABSTRACT

The currently known animal reservoir for MERS-CoV is the dromedary camel. The clinical pattern of the MERS-CoV field infection in dromedary camels is not yet fully studied well. Some pathological changes and the detection of the MERS-CoV antigens by immunohistochemistry have been recently reported. However, the nature of these changes by the scanning electron microscope (SEM) was not revealed. The objective of this study was to document some changes in the respiratory organs induced by the natural MERS-CoV infection using the SEM. We previously identified three positive animals naturally infected with MERS-CoV and two other negative animals. Previous pathological studies on the positive animals showed varying degrees of alterations. MERS-CoV-S and MERS-CoV-Nc proteins were detected in the organs of positive animals. In the current study, we used the same tissues and sections for the SEM examination. We established a histopathology lesion scoring system by the SEM for the nasal turbinate and trachea. Our results showed various degrees of involvement per animal. The main observed characteristic findings are massive ciliary loss, ciliary disorientation, and goblet cell hyperplasia, especially in the respiratory organs, particularly the nasal turbinate and trachea in some animals. The lungs of some affected animals showed signs of marked interstitial pneumonia with damage to the alveolar walls. The partial MERS-CoV-S gene sequencing from the nasal swabs of some dromedary camels admitted to this slaughterhouse confirms the circulating strains belong to clade-B of MERS-CoV. These results confirm the respiratory tropism of the virus and the detection of the virus in the nasal cavity. Further studies are needed to explore the pathological alterations induced by MERS-CoV infection in various body organs of the MERS-CoV naturally infected dromedary camels.

9.
Virus Evol ; 9(1): veac125, 2023.
Article in English | MEDLINE | ID: covidwho-2234649

ABSTRACT

Virus emergence may occur through interspecies transmission and recombination of viruses coinfecting a host, with potential to pair novel and adaptive gene combinations. Camels are known to harbor diverse ribonucleic acid viruses with zoonotic and epizootic potential. Among them, astroviruses are of particular interest due to their cross-species transmission potential and endemicity in diverse host species, including humans. We conducted a molecular epidemiological survey of astroviruses in dromedaries from Saudi Arabia and Bactrian camels from Inner Mongolia, China. Herein, we deployed a hybrid sequencing approach coupling deep sequencing with rapid amplification of complementary deoxyribonucleic acid ends to characterize two novel Bactrian and eight dromedary camel astroviruses, including both partial and complete genomes. Our reported sequences expand the known diversity of dromedary camel astroviruses, highlighting potential recombination events among the astroviruses of camelids and other host species. In Bactrian camels, we detected partially conserved gene regions bearing resemblance to human astrovirus types 1, 4, and 8 although we were unable to recover complete reading frames from these samples. Continued surveillance of astroviruses in camelids, particularly Bactrian species and associated livestock, is highly recommended to identify patterns of cross-species transmission and to determine any epizootic threats and zoonotic risks posed to humans. Phylogenomic approaches are needed to investigate complex patterns of recombination among the astroviruses and to infer their evolutionary history across diverse host species.

10.
Vaccines (Basel) ; 11(2)2023 Feb 12.
Article in English | MEDLINE | ID: covidwho-2229668

ABSTRACT

One of the main mechanisms of inducing an antiviral response depends on 2'-5'-oligoadenylate synthetases (OAS), which sense double-stranded RNA in the cytoplasm and activate RNase L. Mutations leading to the loss of functional OAS1 and OAS2 genes have been identified as important modifiers of the human immune response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we performed comparative genomics to search for inactivating mutations of OAS genes in other species of mammals and to establish a model for the diversifying evolution of the OAS gene family. We found that a recombination of the OAS and OAS-like (OASL) loci has led to the loss of OAS2 in camelids, which also lack OAS3. Both paralogs of OASL and OAS3 are absent in Asian pangolins. An evolutionarily ancient OAS paralog, which we tentatively name OAS4, has been lost in pangolins, bats and humans. A previously unknown OAS gene, tentatively named OAS5, is present in Yangochiroptera, a suborder of bats. These differences in the OAS gene repertoire may affect innate immune responses to coronaviruses and other RNA viruses.

11.
Viral Immunol ; 35(10): 673-680, 2022 12.
Article in English | MEDLINE | ID: covidwho-2188180

ABSTRACT

Middle East respiratory syndrome coronavirus (MERS-CoV) causes viral pneumonia disease in humans. The close contact with camels and drinking milk may cause MERS-CoV transfer to humans. This study was designed to detect the existence of MERS-CoV in camel milk samples collected from healthy animals of various barns located around Saudi Arabia. Camel milk samples were examined for MERS-CoV RNA by real time-quantitative polymerase chain reaction, also enzyme-linked immunosorbent assay was performed to detect IgG antibodies directed against Middle East respiratory syndrome receptor-binding domain. Among 83 camel milk samples tested, the result showed that seven samples (8.4%) were positive for MERS-CoV RNA, whereas 40.9% of camel milk samples had antibodies directed against MERS-CoV. The findings indicate that some regions (East and South part) are characterized by a high incidence of viral antibodies. The Southwestern region displayed the lowest infection rates. Among the camel breeds, the lowest positivity for detection of MERS-CoV RNA and IgG antibodies was found in Sahilia. This could be related to a higher resistance to viral infection of the breed Sahilia and/or to the geographical origin of the camels sampled in the study. This needs to be more explored to reduce spread of infection and also to understand the underlying reasons. The presence of viral RNA in camel milk samples warrants for measures to prevent possible foodborne transmission of MERS-CoV through milk consumption.


Subject(s)
Coronavirus Infections , Middle East Respiratory Syndrome Coronavirus , Humans , Animals , Camelus/genetics , Saudi Arabia/epidemiology , Milk , Immunoglobulin G , RNA, Viral/analysis
12.
Pathogens ; 11(11)2022 Oct 24.
Article in English | MEDLINE | ID: covidwho-2082038

ABSTRACT

After the recent Middle East Respiratory Syndrome coronavirus (MERS-CoV) pandemic in 2013, more attention has been paid to the camel as an important source of zoonotic viral infections. Almost simultaneously, in 2013, new genotypes 7 and 8 of the hepatitis E virus (HEV) were discovered in dromedary and Bactrian camels, respectively. HEV 7 was further shown to be associated with chronic viral hepatitis in a transplant recipient. In this study, serological screening for antibodies to MERS-CoV and hepatitis E virus was carried out on large camel farms in the south and west of Kazakhstan. 6.42% of the tested camels were found to be positive for antibodies to the hepatitis E virus, which indicates its circulation in local camel population. For the first time, antibodies to the hepatitis E virus were found in Bactrians, which have been little studied to date. Antibodies to MERS-CoV were not found in the camel sera.

13.
One Health ; 15: 100436, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-2042067

ABSTRACT

The zoonotic Middle East respiratory syndrome (MERS) is caused by an emerging beta-coronavirus (CoV). The majority of MERS studies have included scattered data from sub-Saharan Africa and the Middle East, and these data have not been analyzed collectively. In this work, a meta-analysis of these studies was conducted to coalesce these results, determine the prevalence and seroprevalence of MERS-CoV in camels and humans, and examine how zoonotic infection rates in dromedary camels are related to human infection rates. After extracting the collected data, the prevalence and seroprevalence at a 95% confidence interval (CI) using a fixed-effects inverse-variance meta-analysis was conducted. Thirteen studies were included. Eight studies included 2905 samples from dromedary camels, of which 1108 (38.14%) were positive for the virus. The prevalence was 8.75[-13.47, 30.98] at 95% CI in dromedary camels and 0.03[-35.23, 35.28] at 95% CI in humans. Ten studies included 7176 serum samples, 5788 (80.66%) of which were positive. The seroprevalence was 20.69[-4.60, 45.99] at 95% CI. The prevalence of MERS-CoV was moderate to high, but the seroprevalence was high. Despite the high prevalence of the virus in camel herds, zoonotic transmissions were not widespread. Further longitudinal and cross-sectional follow-up studies are recommended to provide solid control of MERS-CoV transmission.

14.
Front Vet Sci ; 9: 915475, 2022.
Article in English | MEDLINE | ID: covidwho-2009918

ABSTRACT

Many pathogenic viruses infect camels, generally regarded as especially hardy livestock because of their ability to thrive in harsh and arid conditions. Transmission of these viruses has been facilitated by the commercialization of camel milk and meat and their byproducts, and vaccines are needed to prevent viruses from spreading. There is a paucity of information on the effectiveness of viral immunizations in camels, even though numerous studies have looked into the topic. More research is needed to create effective vaccines and treatments for camels. Because Camels are carriers of coronavirus, capable of producing a powerful immune response to recurrent coronavirus infections. As a result, camels may be a suitable model for viral vaccine trials since vaccines are simple to create and can prevent viral infection transfer from animals to humans. In this review, we present available data on the diagnostic, therapeutic, and preventative strategies for the following viral diseases in camels, most of which result in significant economic loss: camelpox, Rift Valley fever, peste des petits ruminants, bovine viral diarrhea, bluetongue, rotavirus, Middle East respiratory syndrome, and COVID-19. Although suitable vaccines have been developed for controlling viral infections and perhaps interrupting the transmission of the virus from the affected animals to blood-feeding vectors, there is a paucity of information on the effectiveness of viral immunizations in camels and more research is needed. Recent therapeutic trials that include specific antivirals or supportive care have helped manage viral infections.

15.
Vaccines (Basel) ; 10(8)2022 Aug 17.
Article in English | MEDLINE | ID: covidwho-1988069

ABSTRACT

The Middle East respiratory syndrome coronavirus (MERS-CoV) is a zoonotic pathogen that can transmit from dromedary camels to humans, causing severe pneumonia, with a 35% mortality rate. Vaccine candidates have been developed and tested in mice, camels, and humans. Previously, we developed a vaccine based on the modified vaccinia virus Ankara (MVA) viral vector, encoding a full-length spike protein of MERS-CoV, MVA-MERS. Here, we report the immunogenicity of high-dose MVA-MERS in prime-boost vaccinations in mice and camels. METHODS: Three groups of mice were immunised with MVA wild-type (MVA-wt) and MVA-MERS (MVA-wt/MVA-MERS), MVA-MERS/MVA-wt, or MVA-MERS/MVA-MERS. Camels were immunised with two doses of PBS, MVA-wt, or MVA-MERS. Antibody (Ab) responses were evaluated using ELISA and MERS pseudovirus neutralisation assays. RESULTS: Two high doses of MVA-MERS induced strong Ab responses in both mice and camels, including neutralising antibodies. Anti-MVA Ab responses did not affect the immune responses to the vaccine antigen (MERS-CoV spike). CONCLUSIONS: MVA-MERS vaccine, administered in a homologous prime-boost regimen, induced high levels of neutralising anti-MERS-CoV antibodies in mice and camels. This could be considered for further development and evaluation as a dromedary vaccine to reduce MERS-CoV transmission to humans.

16.
The Journal of Risk Finance ; 23(4):418-436, 2022.
Article in English | ProQuest Central | ID: covidwho-1948694

ABSTRACT

Purpose>This research is designed to investigate the presence of market discipline in the banking sector, across Balkan states in Europe. Specifically, the effects of CAMEL variables on the cost of funds and deposit-switching have been assessed.Design/methodology/approach>The CAMEL method of bank evaluation has been applied as well as two measures for market discipline (costs of funds and deposit-switching behaviour). Data have been obtained for 10 Balkan states for the 2006–2019 period. For data analysis, ordinary least squares (OLS) and fixed effects models have been utilized. The generalized method of moments (GMM) method has been deployed as well as a dynamic panel model.Findings>Evidence of market discipline has been found, in the form of a higher cost of funds in the context of capital adequacy (but not for other CAMEL variables). Evidence of market discipline in the form of deposit-switching, however, has not been found. In addition, it has been discovered that bank size and gross domestic product (GDP) growth lower the costs of funds for banks.Originality/value>In the wake of the pandemic, banks need to prepare themselves for very difficult situations and relevant studies can provide help. Therefore, this research has contributed to the developing literature on this topic. In addition, the findings have important practical implications. Results show that banks should maintain adequate levels of capital if they want to control their costs of funds. Results also show that market discipline, in the form of higher costs of funds, can be imposed on banks to discourage excessive risk-taking. Findings highlight the value of appropriate policies and strong supervision of the financial industry. Findings also underline the importance of offering financial incentives to banks. For example, if banks know they will be able to avoid higher costs of funds by controlling their risk levels, they will avoid unrestrained risk-taking.

17.
Journal of ICT Standardization ; 10(2):219-240, 2022.
Article in English | Scopus | ID: covidwho-1934648

ABSTRACT

Last December 2019, health officials in Wuhan, a province from China, identified a novel coronavirus called SARS-CoV-2 causing pneumonia. In March 2020, World Health Organization (WHO) declared COVID-19 disease being a pandemic. During quarantine periods, people all over the globe were living under severe and overwhelming circumstances and expressing feelings of loneliness, dread, and anxiety. The pandemic has had a significant impact on the labor markets. As a result, several employees have lost their jobs while others are in grave danger to lose their positions the next day. In this paper, we developed a hybrid approach integrating sentiment analysis combined with topic modeling to analyze the impact of the COVID-19 pandemic on Moroccan citizens. The data used in this study includes comments collected from a well-known news website in Morocco called Hespress. Our approach follows a two-step process. In the first step, we implement a topic modeling method to analyze and extract topics from Arabic comments, and in the second step, we perform topic-based sentiment analysis to classify people’s feedback on extracted topics. The final results revealed that the expressed sentiments regarding all the topics are highly negative. © 2022 River Publishers

18.
Journal of Public Health in Africa ; 12(SUPPL 1):36-37, 2022.
Article in English | EMBASE | ID: covidwho-1913137

ABSTRACT

Background: Middle East respiratory syndrome coronavirus (MERS-CoV) is an emerging coronavirus that is endemic in dromedary camels. Kenya's >3 million camels have high seroprevalence of antibodies against MERS-CoV, with scant evidence of human infection, possibly due to a lower zoonotic potential of Clade C viruses, predominantly found in African camels. Methods: Between April 2018-March 2020, we followed camels aged 0-24 months from 33 camel-keeping homesteads within 50Km of Marsabit town through collecting deep nasal swabs and documenting signs of illness in camels every two weeks. Swabs were screened for MERS-CoV by reverse transcriptase (RT)-polymerase chain reaction (PCR) testing and virus isolation performed on PCR positive samples with cycle threshold (CT) <20. Both the isolates and swab samples (CT <30) were subjected to whole genome sequencing. Human camel handlers were also swabbed and screened for symptoms monthly and samples tested for MERS-CoV by RT-PCR. Results: Among 243 calves, 68 illnesses were recorded in 58 camels (53.9%);50/68 (73.5%) of illnesses were recorded in 2019, and 39 (57.3%) were respiratory symptoms (nasal discharge, hyperlacrimation and coughing). A total of 124/4,702 camel swabs (2.6%) from 83 (34.2%) calves in 15 (45.5%) enrolled compounds were positive for MERS-CoV RNA. Cases were detected between May-September 2019 with three infection peaks, a similar period when three (1.1%) human PCR-positive but asymptomatic cases were detected among 262 persons handling these herds. Sequencing of camel specimens revealed a Clade C2 virus with identical 12 nucleotide deletion at the 3' end of OFR3 region and one nucleotide insertion at the 5' region but lacked the signature ORF4b deletions of other Clade C viruses. Interpretation: We found high levels of transmission of distinct Clade C MERS-CoV among camels in Northern Kenya, with likely spillover infection to humans. These findings update our understanding of MERS-CoV epidemiology in this region.

19.
Journal of Public Health in Africa ; 12(SUPPL 1):16-17, 2022.
Article in English | EMBASE | ID: covidwho-1913059

ABSTRACT

Background: Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a zoonotic virus transmitted to humans from infected dromedary camels. Coordinated by The Food and Agriculture Organization (FAO), Ethiopia and Kenya have ongoing MERS-CoV surveillance studies in camels. The 5-year project combines research and capacity development, with the aim to improve understanding of the epidemiology of the virus in camels and contribute to the global efforts to reduce zoonotic transmission of MERS-CoV. Key development outcomes of the project include important contributions to One Health operationalization in Ethiopia and Kenya. Methods: Since 2016, cross-sectional and longitudinal studies have been implemented to address evolving objectives, including virus detection and prevalence estimates, identifying risk factors for exposure, understanding antibody kinetics, and phylogenetic and phenotypic characteristics of circulating virus. Results: Results revealed that over 60% of camels from Kenya and over 70% of camels from Ethiopia demonstrate exposure to MERS-CoV, while viral RNA was detected in 0.23% of camels in Kenya and 1.08% of camels in Ethiopia. Viruses isolated from both countries were genetically grouped in Clade C2 with MERS-CoV strains found elsewhere in Africa. Phenotypic characteristics of these isolates suggest that MERS-CoV circulating in Africa poses a lower zoonotic risk than clades A and B of the virus circulating in the Arabian Peninsula. These findings have contributed to a better understanding of MERS-CoV transmission risks that will ultimately inform policy directions on risk mitigation. Conclusion: The project has contributed towards the establishment of multi-sectoral Emerging Pandemic Threats Technical Working Group (EPT-TWG) and MERSCoV TWG in Ethiopia and Kenya, respectively. With the emergence of COVID-19, future directions of MERS-CoV work will focus on applied research of risk mitigation interventions, and institutional capacity building on surveillance for early detection of mutations and possible genetic recombination of MERS-CoV with other zoonotic coronaviruses.

20.
Curr Protoc ; 2(6): e459, 2022 Jun.
Article in English | MEDLINE | ID: covidwho-1898638

ABSTRACT

Single-domain antibodies, including the antigen-binding variable domains of the shark immunoglobulin new antigen receptor and the camelid variable region of the heavy chain, are the smallest antigen recognition domains (∼15 kDa) and have unique characteristics compared to conventional antibodies. They are capable of binding epitopes that are hard to access for classical antibodies and can also be used for therapeutics or diagnostics or as modular building blocks for multi-domain constructs, antibody-drug conjugates, immunotoxins, or chimeric antigen receptor therapy. This article contains detailed procedures for the purification and validation of two single-domain antibodies (one shark and one camel), which bind to the S2 subunit of the SARS-CoV-2 spike protein, using both bacterial and mammalian cell expression systems. It provides a comprehensive reference for the production of single-domain antibodies with high yield, good quality, and purity. © Published 2022. This article is a U.S. Government work and is in the public domain in the USA. Basic Protocol: Production of single-domain antibodies from Escherichia coli Alternate Protocol: Production of single-domain antibodies using the mammalian cell line Expi293F Support Protocol 1: Production and purification of single-domain antibodies on a small scale with the polymyxin B method Support Protocol 2: Validation of single-domain antibodies by ELISA.


Subject(s)
COVID-19 , Sharks , Single-Domain Antibodies , Animals , Antibodies , Camelus , Humans , SARS-CoV-2 , Spike Glycoprotein, Coronavirus
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