A longitudinal study of Middle East respiratory syndrome coronavirus (MERS-CoV) in dromedary camels

Bibliometric analysis of the use of pathological techniques in camel research

Background

Camel pathology research has evolved significantly over the past five decades, reflecting the growing recognition of camels' importance in agriculture, zoonotic disease control, and economic contributions. However, there has been limited evaluation of research trends, thematic advancements, and international collaborations in this field. Aim: This study aimed to conduct a bibliometric analysis of camel pathology research published between 1971 and 2024. The study identified key research themes, assessed collaboration patterns, and highlighted gaps to guide future research efforts in camel pathology.

Results

The analysis included 297 research articles retrieved from Scopus. A steady increase in publications was observed, with a notable surge after 2010 due to advancements in molecular techniques and rising global interest in camel health. Thematic analysis identified well-established motor themes, such as camel histopathology and tuberculosis, while basic themes, such as infertility and postmortem studies, were found to be underexplored. Collaboration analysis revealed the dominance of Saudi Arabia and Egypt, emphasizing their pivotal role in camel research. However, under- represented regions, such as Sub-Saharan Africa, showed limited participation in collaborative networks.

Conclusion

This study highlights the transition from traditional pathological techniques to advanced molecular and epidemiological approaches, enabling better disease detection, diagnosis, and management in camels. Despite significant progress, the slower adoption of cutting-edge technologies in certain regions indicates the need for targeted capacity-building initiatives. By addressing these gaps and fostering international collaborations, camel pathology research can contribute to sustainable development, improved public health, and improved global food security.

A bibliometric analysis of six decades of camel research in North Africa: Trends, collaboration, and emerging themes

Background

Camels play a crucial role in North Africa's economy and agriculture, providing essential products, transportation, and tourism.

Aim

This study conducts a comprehensive bibliometric analysis of camel research in North Africa between 1964 and 2024. The primary objectives are to evaluate research productivity, identify key contributors, and highlight emerging trends.

Methods

Data were collected from the Scopus database, which contained 1805 research documents. Bibliometrix and VOSviewer were used to visualize co-authorship networks, citation patterns, and keyword trends.

Results

The research output has increased dramatically since the mid-2000s, with a peak in publications between 2018 and 2020. Collaborations made up 53.91% of articles. The research clusters in camel studies from North Africa include camel physiology and reproduction, focusing on topics such as ovarian function, semen preservation, and seasonal variations; Microbiology and genetics, addressing microbial infections and genetic diversity; Epidemiology and disease control, which covers studies on disease prevalence, risk factors, and seroprevalence; and Camel milk research, emphasizing its nutritional and therapeutic properties, particularly related to oxidative stress and antioxidants.

Conclusion

Camel research in North Africa has grown significantly, with a focus on health, genetics, and sustainability. However, there are still gaps in molecular and transdisciplinary research, notably in areas such as genetic diversity and ecological integration. Future research should prioritize these areas and foster greater international collaboration to address pressing concerns like climate change.

Structural basis of main proteases of MERS-CoV bound to antineoplastic drug carmofur

Recurrent epidemics of coronaviruses have posed significant threats to human life and health. The mortality rate of patients infected with the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is 35 %. The main protease (Mpro) plays a crucial role in the MERS-CoV life cycle, and Mpro exhibited a high degree of conservation among different coronaviruses. Therefore inhibition of Mpro has become an effective strategy for the development of broad-spectrum anti-coronaviral drugs. The inhibition of SARS-CoV-2 Mpro by the anti-tumor drug carmofur has been revealed, but structural studies of carmofur in complex with Mpro from other types of coronavirus have not been reported. Hence, we revealed the structure of the MERS-CoV Mpro-carmofur complex, analysed the structural basis for the binding of carmofur to MERS-CoV Mpro in detail, and compared the binding patterns of carmofur to Mpros of two different coronaviruses, MERS-CoV and SARS-CoV-2. Considering the importance of Mpros for coronavirus therapy, structural understanding of Mpro inhibition by carmofur could contribute to the design and development of novel antiviral drugs with safe and broad-spectrum efficacy.

Cold-adapted live attenuated MERS-CoV vaccine strain remains attenuated in mice after multiple passages in Vero cells at 37 °C

Middle East respiratory syndrome coronavirus (MERS-CoV) is a zoonotic disease affecting camels and humans. The live attenuated vaccine represents a candidate human vaccine because it can induce strong immune responses in immunized hosts. The attenuated vaccine strain of the highly pathogenic virus can also be used to produce a cell-based vaccine in the BSL2 GMP facility. In this study, we evaluated the reversion potential of pathogenicity to pathogenic wild-type virus to ensure the safety of the live attenuated vaccine strain. We passaged our previously developed cold-adapted live attenuated MERS-CoV vaccine strain at 22 °C (EMC2012-CA22°C) in Vero cells at 37 °C as often as 15 times to determine the potential of pathogenicity reversion in hDPP4 (human dipeptidyl peptidase 4)-transgenic mice, K18-hDPP4. The serial passage of EMC2012-CA22°C in Vero cells at 37 °C up to 15 times did not result in pathogenicity reversion to wild-type MERS-CoV. In K18-hDPP4 mice infected with this virus, no weight loss or mortality was observed, and no virus was detected in tissues such as the lung, kidney, brain, and nasal turbinate. In addition, mice immunized with this virus produced a robust neutralizing antibody response and were fully protected from lethal challenge with wild-type MERS-CoV. The cold-adapted attenuated MERS-CoV vaccine strain (EMC2012-CA22°C) was not reverted to wild-type pathogenic virus after 15 passages in Vero cells at 37 °C.

Inactivated Split MERS-CoV Antigen Prevents Lethal Middle East Respiratory Syndrome Coronavirus Infections in Mice

Middle East respiratory syndrome coronavirus (MERS-CoV) causes fatal infections, with about 36% mortality in humans, and is endemic to the Middle East. MERS-CoV uses human dipeptidyl peptidase 4 (hDPP4) as a receptor for infection. Despite continued research efforts, no licensed vaccine is available for protection against this disease in humans. Therefore, this study sought to develop an inactivated fragmented MERS-CoV vaccine grown in Vero cells in an hDPP4-transgenic mouse model. Two-dose immunisation in mice with 15, 20, or 25 μg of spike proteins of inactivated split MERS-CoV antigens induced neutralising antibodies, with titres ranging from NT 80 to 1280. In addition, all immunised mice were completely protected, with no virus detection in tissues, weight loss, or mortality. The immunised splenocytes produced more cytokines that stimulate immune response (IFN-γ and TNF-α) than those that regulate it (IL-4 and IL-10). Taken together, the inactivated fragmented MERS-CoV vaccine is effective for the protection of mice against lethal MERS-CoV. Thus, the inactivated fragmented MERS-CoV vaccine warrants further testing in other hosts.