First molecular detection of hepatitis E virus genome in camel and pig faecal samples in Ethiopia

Exposure to three zoonotic pathogens in the pig population of Southern Italy

Pigs represent a reservoir of infectious diseases that can be transmitted to humans through feeding or close contact. The aim of this study was to evaluate the seroprevalence of three zoonotic pathogens (Brucella suis, Mycobacterium avium, and Paslahepevirus balayani, also called hepatitis E virus) in the swine population in the Campania region, Southern Italy. A total of 370 animals from 31 farms were sampled and tested with specific commercial ELISAs. Antibodies against hepatitis E virus were detected in 41.4 % of the animals and in almost all the farms (83.8 %). Mycobacterium avium and Brucella suis were less widespread (seroprevalences of 3.5 % and 0 % at the individual level, 32.3 % and 0 % at the farm level, respectively). The univariate analysis of risk factors showed that sex (males), location (Naples), age (growers and finishers), farm size, and system (intensive) were related to higher hepatitis E virus prevalences. We also found higher seroprevalences in pigs belonging to districts where bovines were the main ruminant species. This variable and age were confirmed as risk factors also in multivariate analysis. The data obtained highlighted how pigs are HEV reservoirs also in southern Italy and that pigs in this region are also exposed to Mycobacterium avium but not to Brucella suis.

Zoonotic and Food-Related Hazards Due to Hepatitis A and E in Africa: A Systematic Review and Meta-Analysis

Introduction

Foodborne infections are caused by a wide spectrum of microbial pathogens, and they pose a significant global health threat, resulting in millions of cases and thousands of fatalities annually. Among these pathogens, human viruses, including Hepatitis A virus (HAV) and Hepatitis E virus (HEV), play a significant role in foodborne viral outbreaks, especially in Africa. This systematic review determined the prevalence of these viruses in livestock and produce in Africa.

Method

A systematic search strategy was implemented following the PRISMA guidelines. Databases such as African Journal Online, Web of Science, Scopus, and PubMed were searched from their inception until November 30, 2023. Descriptive statistics and a proportional meta-analysis utilising a random-effects model with a 95% confidence interval were employed in the data analysis. The Cochrane risk-of-bias tool (ROB2) was utilised to evaluate the potential for bias in each study.

Results

The search identified 27 articles that met the inclusion criteria, among which seven focused on HAV, comprising a total of 309 samples, whereas 20 studies focused on HEV, comprising a total of 4238 samples. Egypt had the highest number of studies, followed by Cameroon and Nigeria. The meta-analysis revealed an overall prevalence of 33.8% (95% CI: 17.0-50.6) for HAV in ducks and shellfish and 22.0% (95% CI: 12.1-31.8) for HEV in various livestock. Genotype 3 was identified as the predominant genotype, for both HAV and HEV.

Conclusion

This review revealed a high prevalence of HAV and HEV in livestock populations in Africa, shedding light on the potential risks associated with zoonotic and/or food-related infections. There is a need for continued surveillance and monitoring of these viruses in both animals and food products to mitigate the risk of foodborne outbreaks and protect human health.

The one-humped camel: The animal of future, potential alternative red meat, technological suitability and future perspectives

The 2020 world population data sheet indicates that world population is projected to increase from 7.8 billion in 2020 to 9.9 billion by 2050 (Increase of more than 25%). Due to the expected growth in human population, the demand for meats that could improve health status and provide therapeutic benefits is also projected to rise. The dromedary also known as the Arabian camel, or one-humped camel ( Camelus dromedarius), a pseudo ruminant adapted to arid climates, has physiological, biological and metabolic characteristics which give it a legendary reputation for surviving in the extreme conditions of desert environments considered restrictive for other ruminants. Camel meat is an ethnic food consumed across the arid regions of Middle East, North-East Africa, Australia and China. For these medicinal and nutritional benefits, camel meat can be a great option for sustainable meat worldwide supply. A considerable amount of literature has been published on technological aspects and quality properties of beef, lamb and pork but the information available on the technological aspects of the meat of the one humped camel is very limited. Camels are usually raised in less developed countries and their meat is as nutritionally good as any other traditional meat source. Its quality also depends on the breed, sex, age, breeding conditions and type of muscle consumed. A compilation of existing literature related to new technological advances in packaging, shelf-life and quality of camel meat has not been reviewed to the best of our knowledge. Therefore, this review attempts to explore the nutritional composition, health benefits of camel meat, as well as various technological and processing interventions to improve its quality and consumer acceptance. This review will be helpful for camel sector and highlight the potential for global marketability of camel meat and to generate value added products.

Hepatitis E Seroprevalence and Detection of Genotype 3 Strains in Domestic Pigs from Sierra Leone Collected in 2016 and 2017

Hepatitis E virus (HEV) is the main cause of acute hepatitis in humans worldwide and is responsible for a large number of outbreaks especially in Africa. Human infections are mainly caused by genotypes 1 and 2 of the genus Paslahepevirus, which are exclusively associated with humans. In contrast, viruses of genotypes 3 and 4 are zoonotic and have their main reservoir in domestic and wild pigs, from which they can be transmitted to humans primarily through the consumption of meat products. Both genotypes 3 and 4 are widespread in Europe, Asia, and North America and lead to sporadic cases of hepatitis E. However, there is little information available on the prevalence of these genotypes and possible transmission routes from animal reservoirs to humans in African countries. We therefore analysed 1086 pig sera collected in 2016/2017 in four districts in Sierra Leone for antibodies against HEV using a newly designed in-house ELISA. In addition, the samples were also analysed for HEV RNA by quantitative real-time RT-PCR. The overall seroprevalence in Sierra Leone was low with only 44 positive sera and a prevalence of 4.0%. Two serum pools were RT-PCR-positive and recovered partial sequences clustered into the genotype 3 (HEV-3) of the order Paslahepevirus, species Paslahepevirus balayani. The results are the first evidence of HEV-3 infection in pigs from Sierra Leone and demonstrate a low circulation of the virus in these animals to date. Further studies should include an examination of humans, especially those with close contact with pigs and porcine products, as well as environmental sampling to evaluate public health effects within the framework of a One Health approach.

Investigating animal reservoirs for hepatitis E virus in Bangui, Central African Republic

BACKGROUND

Hepatitis E virus (HEV) is a major cause of enterotropic viral hepatitis, a major public health problem in many developing countries. In Central African Republic (CAR), HEV genotypes 1, 2, and 3 have been found to have an impact on human health. However, data on HEV in animal reservoirs are still lacking for CAR. Here, we investigated the presence of HEV in farmed pigs and goats in Bangui, the capital city of CAR, using molecular methods.

METHODOLOGY

In a prospective study, fecal samples from 61 pigs and 39 goats from farms in five districts (2nd, 4th, 6th, 7th, 8th) of Bangui were collected and tested for HEV RNA by real-time RT-PCR. The samples were further analyzed by nested-PCR and sequenced to determine the genotype and subtype to which the virus belong.

RESULTS

In total, 22/100 (22.0%) feces samples were successfully amplified for HEV RNA by real time RT-PCR. All positive samples were from pigs (22/61; 36.1%), while all goat samples were negative (0/39). Twelve HEV RNA samples (12/22 or 54.5%) were successfully amplified by nested RT-PCR, and subsequently sequenced. Phylogenetic analysis revealed that the obtained sequences clustered with subtype 3h and were genetically related to the human HEV sequences from CAR.

CONCLUSION

This study confirms that pigs constitute an HEV reservoir, with genotype 3 being the major circulating strain. Further studies are needed to investigate other local reservoirs and to improve knowledge of the molecular epidemiology of HEV in CAR.

Zoonotic diseases transmitted from the camels

BACKGROUND

Zoonotic diseases, infections transmitted naturally from animals to humans, pose a significant public health challenge worldwide. After MERS-CoV was discovered, interest in camels was raised as potential intermediate hosts for zoonotic viruses. Most published review studies pay little attention to case reports or zoonotic epidemics where there is epidemiological proof of transmission from camels to humans. Accordingly, any pathogen found in camels known to cause zoonotic disease in other animals or humans is reported.

METHODS

Here, zoonotic diseases linked to camels are reviewed in the literature, focusing on those with epidemiological or molecular evidence of spreading from camels to humans. This review examines the risks posed by camel diseases to human health, emphasizing the need for knowledge and awareness in mitigating these risks.

RESULTS

A search of the literature revealed that eight (36.4%) of the 22 investigations that offered convincing evidence of camel-to-human transmission involved MERS, five (22.7%) Brucellosis, four (18.2%) plague caused by Yersinia pestis, three (13.6%) camelpox, one (4.5%) hepatitis E, and one (4.5%) anthrax. The reporting of these zoonotic diseases has been steadily increasing, with the most recent period, from 2010 to the present, accounting for 59% of the reports. Additionally, camels have been associated with several other zoonotic diseases, including toxoplasmosis, Rift Valley fever, TB, Crimean-Congo hemorrhagic fever, and Q fever, despite having no evidence of a transmission event. Transmission of human zoonotic diseases primarily occurs through camel milk, meat, and direct or indirect contact with camels. The above-mentioned diseases were discussed to determine risks to human health.

CONCLUSION

MERS, Brucellosis, plague caused by Y. pestis, camelpox, hepatitis E, and anthrax are the main zoonotic diseases associated with human disease events or outbreaks. Transmission to humans primarily occurs through camel milk, meat, and direct contact with camels. There is a need for comprehensive surveillance, preventive measures, and public health interventions based on a one-health approach to mitigate the risks of zoonotic infections linked to camels.

A Systematic Review of Hepatitis E Virus Detection in Camels

Hepatitis E virus (HEV) represents a major cause of acute hepatitis and is considered an emerging public health problem around the world. In the Middle East's and Africa's arid regions, where camels frequently interact with human populations and camel-derived food products are a component of the food chain, camel-borne zoonotic HEV infection is a potential threat. To date, no review paper has been published on HEV in camels. As such, the purpose of the current work is to provide a scientific review of the identification of HEV genotypes seven and eight in camels worldwide to have a better understanding of the current status of this topic and to identify gaps in the current knowledge. Searches were carried out in the electronic databases PubMed, Mendeley, Web of Science, and Scopus, including studies published until 31 December 2022 (n = 435). Once the databases were checked for duplicate papers (n = 307), the exclusion criteria were applied to remove any research that was not relevant (n = 118). As a result, only 10 papers were found to be eligible for the study. Additionally, in eight of the ten studies, the rates of HEV infection were found to be between 0.6% and 2.2% in both stool and serum samples. Furthermore, four studies detected HEV genotype seven in dromedary camels, and two studies have shown HEV genotype eight in Bactrian camels. Interestingly, these genotypes were recently reported in camels from the Middle East and China, where one human infection with HEV genotype seven has been associated with the consumption of contaminated camel meat and milk. In conclusion, more research will be needed to determine the prevalence of HEV infection in camels around the world as well as the risk of foodborne transmission of contaminated camel products. As camels are utility animals in several countries, HEV in these animals may pose a potential risk to public health.