Research Publications (Food Safety)

Hepatitis E virus (HEV) is an enteric RNA virus from the family Hepeviridae with five genotypes (genotypes 1‐4 and 7) known to infect humans. HEV infection is known to have a zoonotic swine origin in industrialized countries. The role of pigs and wild boars as major reservoirs for human infection is today well‐established, however the list of new animal reservoirs is ever‐expanding as new HEV strains are continuously being found in a broad host range.

In recent decades multiple subtypes (i.e., H9N2, H5N1, and H7N9) of avian influenza virus (AIV) have become widespread in China, which has caused enormous economic losses and posed considerable threats to public health.

Classical swine fever virus (CSFV) and pseudorabies virus (PRV) are two of the most significant trade‐limiting pathogens affecting swine worldwide. Both viruses are endemic to China where millions of kilograms of feed ingredients are manufactured and subsequently imported into the United States.

The introduction and spread of porcine epidemic diarrhea virus (PEDV) in North America resulted in significant death loss in the swine industry. As the industry learned how to manage this disease many new risks were identified, including the potential for feed and feed ingredients to become contaminated and spread PEDV. In addition, biosecurity practices were reevaluated and strengthened throughout the industry.

Biosecurity is crucial for infectious disease prevention, more importantly in the absence of vaccination. The need for improving the implementation of biosecurity practices was highlighted in French duck farms following the 2016–2017 H5N8 Highly Pathogenic Avian Influenza (HPAI) epidemic. Farmers have multiple reasons for not implementing biosecurity practices: external (time, money) and internal (socio‐psychological).

The cover image is based on the Short Communication A novel reassortant influenza A (H1N1) virus infection in swine in Shandong Province, eastern China, by Zhijun Yu et al., https://doi.org/10.1111/tbed.13360.

Infectious bronchitis virus (IBV), an ongoing emergence enveloped virus with a single‐stranded positive‐sense RNA genome, belongs to the Gammacoronavirus genus in the Coronaviridae family. IBV‐associated tracheitis, nephritis, salpingitis, proventriculitis and egg drop have caused devastating economic losses to poultry industry worldwide. Since the end of 2018, a remarkably increasing number of commercial broilers and layers, vaccinated or not, were infected with IBV in China.

In recent decades, cases of autochthonous hepatitis E (HE) have sharply increased in European countries where foodborne transmission is considered the main route of HE virus (HEV) transmission. Although rabbits are considered the main reservoir of the zoonotic HEV‐3ra subtype, information on the role of wild lagomorphs in the epidemiology of HEV remains scarce.

The carriage of two important pathogens of pigs, i.e. enterotoxigenic E. coli (ETEC) and Clostridioides difficile, was investigated in 104 cloacal samples from wild griffon vultures (Gyps fulvus) fed on pig carcasses at supplementary feeding stations (SFS), along with their level of antimicrobial resistance (AMR). E. coli was isolated from 90 (86.5%) samples but no ETEC was detected, likely because ETEC fimbriae confer the species specificity of the pathogen.

Meat of the South American camelids (SACs) llama and alpaca is an important source of animal protein and income for rural families in the Andes, and a product with significant growth potential for local and international markets. However, infestation with macroscopic cysts of the coccidian protozoon Sarcocystis aucheniae, a parasitosis known as SAC sarcocystosis, significantly hampers its commercialization. There are no validated methods to diagnose the presence of S.

When assessing the role of live animal trade networks in the spread of infectious diseases in livestock, attention has focused mainly on direct movements of animals between premises, whereas the role of haulage vehicles used during transport, an indirect route for disease transmission, has largely been ignored.

Asian‐origin H5N8 highly pathogenic avian influenza (HPAI) viruses of the H5 Goose/Guangdong/96 lineage, clade 2.3.4.4 group B reached South Africa by June 2017. By the end of that year, 5.4 million layers and broiler chickens died or were culled, with total losses in the poultry industry estimated at US$ 140 million, and thousands of exotic birds in zoological collections, endangered endemic species and backyard poultry and pet birds also perished.

In Europe, African swine fever virus (ASFV) is one of the most threatening infectious transboundary diseases of domestic pigs and wild boar. In September 2018, ASF was detected in wild boar in the South of Belgium. France, as a bordering country, is extremely concerned about the ASF situation in Belgium and an active preparedness is ongoing in the country.

Effective control of avian diseases in domestic populations requires understanding of the transmission dynamics facilitating viral emergence and spread. In 2016–17, Italy experienced a significant avian influenza epidemic caused by a highly pathogenic A(H5N8) virus, which affected domestic premises housing around 2.7 million birds, primarily in the north‐eastern regions with the highest density of poultry farms (Lombardy, Emilia‐Romagna and Veneto).

Since 2004, there have been multiple outbreaks of H5 highly pathogenic avian influenza (HPAI) viruses in Laos. Here, we isolated H5N1 HPAI viruses from poultry outbreaks in Laos during 2015–2018 and investigated their genetic characteristics and pathogenicity in chickens. Phylogenetic analysis revealed that the isolates belonged to clade 2.3.2.1c, and that they differed from previous Laos viruses with respect to genetic composition.

In July 2016, an avian influenza outbreak in duck farms in Yogyakarta province was reported to Disease Investigation Center (DIC) Wates, Indonesia with approximately 1,000 ducks death or culled. In this study, two avian influenza (AI) virus subtypes, A/duck/Bantul/04161291‐OR/2016 (H5N1) and A/duck/Bantul/04161291‐OP/2016 (H9N2) isolated from ducks in the same farm during an AI outbreak in Bantul district, Yogyakarta province were sequenced and characterized.

The etiology and pathogenesis of bovine respiratory disease (BRD) is complex and involves the interplay of infectious agents, management and environmental factors. Previous studies of BRD focused on ante mortem samples from the upper respiratory tract and identified several unconventional viruses. The lung, however, is the primary location where significant BRD lesions are usually found, and is a common post mortem diagnostic specimen.

The H5N8 highly pathogenic avian influenza viruses (HPAIV) belonging to clade 2.3.4.4 spread from Eastern China to Korea in 2014 and caused outbreaks in domestic poultry until 2016. To understand how H5N8 HPAIV spread at host species level in Korea during 2014‐2016, a Bayesian phylogenetic analysis was used for ancestral state reconstruction and estimation of the host transition dynamics between wild waterfowl, domestic ducks, and chickens.

Brucellosis is a global pandemic infectious zoonosis. Brucella canis is a rare source of human brucellosis in China, and its public health significance remains under debate. Moreover, data pertaining to the epizootiological characteristics and geographical origin of B. canis on a nationwide scale are limited, and the risk to public safety posed by B. canis infections is unknown.

Rift Valley fever (RVF) is a vector‐borne viral disease of domestic ruminants, camels and man, characterized by widespread abortions and neonatal deaths in animals, and flu‐like symptoms, which can progress to hepatitis and encephalitis in humans. The disease is endemic in Africa, Saudi Arabia and Yemen, and outbreaks occur after periods of high rainfall, or in environments supporting the proliferation of RVF virus (RVFV) infected mosquito vectors.

Avian influenza H7N9 viruses have caused five epidemic waves of human infections since the first human cases were reported in 2013. In 2016, the initial low pathogenic avian influenza (LPAI) H7N9 viruses became highly pathogenic, acquiring multi‐basic amino acids at the hemagglutinin cleavage site. This highly pathogenic avian influenza (HPAI) H7N9 viruses have been detected in poultry and humans in China, causing concerns of a serious threat to global public health.

Genotype S H9N2 avian influenza virus, which has been predominant in China since 2010, and contributed its entire internal gene cassette to the genesis of novel reassortant influenza viruses, including H5Nx, H7N9 and H10N8 viruses that pose great threat to poultry and humans. A key feature of the genotype S H9N2 virus is the substitution of G1‐like M and PB2 genes for the earlier F/98‐like M and PB2 of genotype H virus.

Free‐range poultry farms have a high risk of introduction of avian influenza viruses (AIV), and it is presumed that wild (water)birds are the source of introduction. There is very scarce quantitative data on wild fauna visiting free‐range poultry farms. We quantified visits of wild fauna to a free‐range area of a layer farm, situated in an AIV hot‐spot area, assessed by video‐camera monitoring.

In the last 10 years, many atypical novel members of Brucella species have been reported, including several Brucella inopinata‐like strains in wild‐caught and “exotic” amphibians from various continents. In 2017, a strain of Brucella was isolated for the first time in animals from a French farm producing frogs – Pelophylax ridibundus – for human consumption, and identified as B. microti‐like.

For several years, poultry production in Egypt has been suffering from co‐circulation of multiple respiratory viruses including highly pathogenic avian influenza virus (HPAIV) H5N1 (clade 2.2.1.2) and low pathogenic H9N2 (clade G1‐B). Incursion of HPAIV H5N8 (clade 2.3.4.4b) to Egypt in November 2016 via wild birds followed by spread into commercial poultry flocks further complicated the situation.