Comparison of historical and contemporary isolates of Senecavirus A

Senecavirus A (SVA) was discovered as a cell culture contaminant in 2002, and multiple attempts to experimentally reproduce disease were unsuccessful. Field reports of porcine idiopathic vesicular disease (PIVD) cases testing PCR positive for SVA in addition to outbreaks of PIVD in Brazil and the United States in 2015 suggested SVA was a causative agent, which has now been consistently demonstrated experimentally. Ease of experimental reproduction of disease with contemporary strains of SVA raised questions concerning the difficulty of reproducing vesicular disease with historical isolates. The following study was conducted to compare the pathogenicity of SVA between historical and contemporary isolates in growing pigs. Six groups of pigs (n = 8) were intranasally inoculated with the following SVA isolates: SVV001/2002, CAN/2011, HI/2012, IA/2015, NC/2015, SD/2015. All isolates induced vesicular disease in at least half of the inoculated pigs from each group. All pigs replicated virus as demonstrated by serum and/or swab samples positive for SVA by quantitative PCR. Pig sera tested by virus neutralization assay demonstrated cross-neutralizing antibodies against all viruses utilized in the study. Cross-neutralizing antibodies from pigs inoculated with historical isolates were lower than those pigs that were inoculated with contemporary isolates. Phylogenetic analysis revealed two clades with SVV001/2002 being in a separate clade compared to the other five isolates. Although differences in the infection kinetics and sequences of these six isolates were found, clinical presentation of vesicular disease was similar between both historical and contemporary isolates.

Mycobacterium microti Infection in Free-Ranging Wild Boar, Spain, 2017-2019

Mycobacterium microti is a member of the Mycobacterium tuberculosis complex that causes pathology in many mammals. M. microti infections have been found in some countries in Europe. We report an outbreak of tuberculosis caused by M. microti in wild boars in Spain.

Influenza D Virus Circulation in Cattle and Swine, Luxembourg, 2012-2016

We detected antibodies against influenza D in 80.2% of the cattle sampled in Luxembourg in 2016, suggesting widespread virus circulation throughout the country. In swine, seroprevalence of influenza D was low but increased from 0% to 5.9% from 2012 to 2014–2015.

Genetic evolution analysis and pathogenicity assessment of porcine epidemic diarrhea virus strains circulating in part of China during 2011-2017

In recent years, the outbreaks of porcine epidemic diarrhea (PED) caused by the highly virulent porcine epidemic diarrhea virus (PEDV) variants occurred frequently in China, resulting in severe economic impacts to the pork industry. In this study, we selected and analyzed the genetic evolution of 15 PEDV representative strains that were identified in fecal samples of diarrheic piglets in 10 provinces and cities during 2011-2017. The phylogenetic analysis indicated that all the 15 PEDV isolates clustered into G2 genotype associated with the current circulating strains. Compared with the genome of the prototype strain CV777, these strains had 103-120 amino acid mutations in their S proteins, most of which were in the N terminal domain of S1 (S1-NTD). We also found 37 common mutations in all these 15 strains, although these strains shared 96.9-99.7% nucleotide homology and 96.3-99.8% amino acid homology in the S protein compared with the other original pandemic strains. Computational analysis showed that these mutations may lead to remarkable changes in the conformational structure and asparagine (N)-linked glycosylation sites of S1-NTD, which may be associated with the altered pathogenicity of these variant PEDV strains. We evaluated the pathogenicity of the PEDV strain FJzz1 in piglets through oral and intramuscular infection routes. Compared with oral infection, intramuscular infection could also cause typical clinical signs but with a slightly delayed onset, confirming that the variant PEDV isolate FJzz1 was highly pathogenic to suckling piglets. In conclusion, we analyzed the genetic variation and pathogenicity of the emerging PEDV isolates of China, indicating that G2 variant PEDV strains as the main prevalent strains that may mutate continually. This study shows the necessity of monitoring the molecular epidemiology and the etiological characteristics of the epidemic PEDV isolates, which may help better control the PED outbreaks.

Novel Pestivirus Species in Pigs, Austria, 2015

A novel pestivirus species was discovered in a piglet-producing farm in Austria during virologic examinations of congenital tremor cases. The emergence of this novel pestivirus species, provisionally termed Linda virus, in domestic pigs may have implications for classical swine fever virus surveillance and porcine health management.

Tuberculosis-Associated Death among Adult Wild Boars, Spain, 2009-2014

We investigated adult Eurasian wild boar (Sus scrofa) survival and death in 2 tuberculosis-endemic populations with different harvest pressure in Spain. Overall, tuberculosis accounted for 30% of total deaths. Increased survival in protected areas has direct implications for wild boar management and tuberculosis control.

Detection and Genotyping of Coxiella burnetii in Pigs, South Korea, 2014-2015

We assessed Coxiella burnetii prevalence and genotypes in pigs in South Korea during 2014–2015. Prevalence was low among 1,030 samples tested by ELISA and immunofluorescent assay and 1,124 samples tested by PCR. Despite this finding, possible transmission of C. burnetii from pigs to humans cannot be excluded.

Porcine Hemagglutinating Encephalomyelitis Virus and Respiratory Disease in Exhibition Swine, Michigan, USA, 2015

Acute outbreaks of respiratory disease in swine at agricultural fairs in Michigan, USA, in 2015 raised concern for potential human exposure to influenza A virus. Testing ruled out influenza A virus and identified porcine hemagglutinating encephalomyelitis virus as the cause of influenza-like illness in the affected swine.

Porcine epidemic diarrhea in China

Porcine epidemic diarrhea (PED) is a contagious intestinal disease caused by Porcine epidemic diarrhea virus (PEDV) that characterized by vomiting, diarrhea, and dehydration. PEDV was first identified in the 1980s in China, and since then, it has become one of the most common viral causes of diarrhea. In October 2010, a large-scale outbreak of PED caused by a PEDV variant occurred in China, resulting in tremendous economic losses. This review presents a comprehensive description of PEDV history, prevalence, molecular features, and prevention and control strategies in China.

New emergence pattern with variant porcine epidemic diarrhea viruses, South Korea, 2012-2015

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By the application of Bayesian phylogeographical analysis, this study demonstrated the spatial- temporal transmission of PEDVs within Korea.

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Of the recent emerged G2a viruses, J3142 strains showed potential recombination breakpoint (376–2,143nt) of S1 gene between KNU1303_Korea strain_G2a (KJ451046) and 45RWVCF0712_Thailand strain_G2b (KF724935).

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The pandemic G2a virus was partial neutralized by the antibodies invoked by the G1- based PED vaccine virus.

Since outbreaks of porcine epidemic diarrhea virus (PEDV) in the United States in 2013, explosive outbreaks of PED in South Korea have infected all age groups of pigs in 2014–2015 year. This study analyzed a large collection of the Spike protein coding gene to infer the spatial-temporal diffusion history of PEDV. The studying results suggested that PEDVs in Korea belonged to different genogroups. While classical G1 was continuingly circulating between provinces of Korea, the pandemic G2a were recently introduced from China and USA. By the application of Bayesian phylogeographical analysis, this study demonstrated the spatial-temporal transmission of PEDVs within Korea. Of the recent emerged G2a viruses, J3142 strains showed potential recombination breakpoint (376–2,143nt) of S1 gene between KNU1303_Korea strain_G2a (KJ451046) and 45RWVCF0712_Thailand strain_G2b (KF724935). The pandemic G2a virus was partial neutralized by the antibodies invoked by the G1- based PED vaccine virus.

[Trichinae, pigs and veterinary public health: The introduction of the microscopic world into the scientific basis for meat inspection (Barcelona, 1870s)]

During the second half of the 19th century, Spanish authorities began developing specific programs on the safety of certain foods intended for human consumption. This paper analyses the key features that gave rise to the inclusion of the veterinarian in the administrative structure responsible for safeguarding public health. Among the aspects covered, special focus is put on the relationship between human and animal medicine at a time when growing public alarm in relation to certain zoonoses contributed to shaping the notion of veterinary public health. The appearance of a disease in pigs that was transmissible through the consumption of parasitized meat set the scene for veterinary inspection to be associated with the protection of public health. The outbreaks of trichinosis all over Spain in the 1870's proved the existence of contagium animatum in a pre-bacteriology era, and this led to the introduction of improvements in food inspection. In this sense, microscopic examination of pork products encouraged the modernization of inspection tasks undertaken by veterinarians, which had previously focused on the organoleptic evaluation of meat and fish and on unveiling fraud. The introduction of microscopes was widely accepted and established a watershed between acceptable and unacceptable methods of carrying out the examination of meat. Furthermore, this "technological" method of diagnosis brought veterinary medicine closer to other more prestigious health professions, at least in theory. Among other aspects, the acceptance of trichinae as an exogenous cause of disease contributed to 19th century doctors learning about the idea of pathogenic microorganisms from veterinarians. At a social level, the use of the microscope was seen as a way of preventing the transmission to people of an animal disease that was very much in the public eye at the time. From the political point of view, the process -analysed in this paper from the perspective of veterinarians in Barcelona- allows a glimpse of the contrast between the desire of some Catalan veterinarians to modernize their profession and what was happening in others parts of Spain.

Influenza A subtype H3 viruses in feral swine, United States, 2011-2012

To determine whether, and to what extent, influenza A subtype H3 viruses were present in feral swine in the United States, we conducted serologic and virologic surveillance during October 2011-September 2012. These animals were periodically exposed to and infected with A(H3N2) viruses, suggesting they may threaten human and animal health.

History of Swine influenza viruses in Asia

The pig is one of the main hosts of influenza A viruses and plays important roles in shaping the current influenza ecology. The occurrence of the 2009 H1N1 pandemic influenza virus demonstrated that pigs could independently facilitate the genesis of a pandemic influenza strain. Genetic analyses revealed that this virus was derived by reassortment between at least two parent swine influenza viruses (SIV), from the northern American triple reassortant H1N2 (TR) and European avian-like H1N1 (EA) lineages. The movement of live pigs between different continents and subsequent virus establishment are preconditions for such a reassortment event to occur. Asia, especially China, has the largest human and pig populations in the world, and seems to be the only region frequently importing pigs from other continents. Virological surveillance revealed that not only classical swine H1N1 (CS), and human-origin H3N2 viruses circulated, but all of the EA, TR and their reassortant variants were introduced into and co-circulated in pigs in this region. Understanding the long-term evolution and history of SIV in Asia would provide insights into the emergence of influenza viruses with epidemic potential in swine and humans.

The "swinish multitude": controversies over hogs in antebellum New York City

In the first half of the nineteenth century, New Yorkers fought passionately over the presence of hogs on their streets and in their city. New York’s filthy streets had cultivated an informal economy and a fertile environment for roaming creatures. The battles—both physical and legal—reveal a city rife with class tensions. After decades of arguments, riots, and petitions, cholera and the fear of other public health crises ultimately spelled the end for New York’s hogs. New York struggled during this period to improve municipal services while adapting to a changing economy and rapid population growth. The fights between those for and against hogs shaped New York City’s landscape and resulted in new rules for using public space a new place for nature in the city.

Research reflections

Dr Switzer received D.V.M, from Texas A and M, in 1948, M.S. and a Ph.D, from Iowa State University in 1951 and 1954 and the Dr.h.c. from the University of Vienna, in 1979. He was Professor of Iowa State University, Veterinary Medical Research Inst, during 1961-74. He later became the Associate Dean for Research, ISU College of Veterinary Medicine, 1974-90. In 1990 he became Distinguished Professor emeritus, Iowa State University, 1990 and Associate Dean emeritus, in 1990 to the present. He has won the following honors and awards: Borden Scholarship Award, Honorary Master Swine Producer, ISU Faculty Citation, ISU Distinguished Professor, American Feed Manufacturers Vet. Med. Research Award, Iowa Inventors' Hall of Fame, National Hog Farmer Award, Gamma Sigma Delta Award, International Award of Merit, Gamma Sigma Delta, Howard W. Dunne Memorial Award, Iowa Veterinarian of the year, 1988 in addition to several others. Switzer Research Award established at ISU College of Veterinary Medicine, Selected as one of the 150 most influential faculty members in the 150 year history of ISU, Vaccines developed by W. P. Switzer were selected as one of the 150 most valuable contributions in the history of ISU. DR. Switzer's patents: A) Use of Sulfonamides for Treatment of Atrophic Rhinitis in Swine; B) Vaccine for Control of Atrophic Rhinitis in Swine, and xx Vaccine for Control and Prevention of Kennel Cough in Dogs. He has also served on the following Advisory Boards: A) Animal Health Advisor, Merck and Co, five years; B) Animal Health Advisor, Pfizer, Inc, six years; and C) Animal Health Advisor, Diamond-Shamrock, two years.

[Christopher Columbus flu. A hypothesis for an ecological catastrophe]

When Christopher Columbus and his men embarked on the second Colombian expedition to the New World (1493), the crew suffered from fever, respiratory symptoms and malaise. It is generally accepted that the disease was influenza. Pigs, horses and hens acquired in Gomera (Canary Islands) traveled in the same ship. The pigs may well have been the origin of the flu and the intermediary hosts for genetic recombination of other viral subtypes. The Caribbean archipelago had a large population of birds, the natural reservoir of the avian influenza virus. In this ecological scenario there was a concurrence of several biological elements that had never before coexisted in the New World: pigs, horses, the influenza virus and humans. We propose that birds are likely to have played an important role in the epidemiology of the flu occurring on the second Colombian trip, which caused a fatal demographic catastrophe, with an estimated mortality of 90% among the natives.

Evolution of ascariasis in humans and pigs: a multi-disciplinary approach

The nematode parasite Ascaris lumbricoides infects the digestive tracts of over 1.4 billion people worldwide, and its sister species, Ascaris suum, has infected a countless number of domesticated and feral pigs. It is generally thought that the putative ancestor to these worms infected either humans or pigs, but with the advent of domestication, they had ample opportunity to jump to a new host and subsequently specialize and evolve into a new species. While nuclear DNA makers decisively separate the two populations, mitochondrial sequences reveal that three major haplotypes are found in A. suum and in A. lumbricoides, indicating either occasional hybridization, causing introgression of gene trees, or retention of polymorphism dating back to the original ancestral species. This article provides an illustration of the combined contribution of parasitology, archaeoparasitology, genetics and paleogenetics to the history of ascariasis. We specifically investigate the molecular history of ascariasis in humans by sequencing DNA from the eggs of Ascaris found among ancient archeological remains. The findings of this paleogenetic survey will explain whether the three mitochondrial haplotypes result from recent hybridization and introgression, due to intensive human-pig interaction, or whether their co-occurrence predates pig husbandry, perhaps dating back to the common ancestor. We hope to show how human-pig interaction has shaped the recent evolutionary history of this disease, perhaps revealing the identify of the ancestral host.

History of trichinellosis surveillance

The origin of trichinellosis, which existed in ancient times as testified by the discovery of parasite larvae on an Egyptian mummy, unfolded in several stages: discovery of encapsulated larvae (in the 1820s), identification and scientific description of these larvae (Paget & Owen, 1835), followed by experimental infestations of animals (dogs, pigs, rabbits, mice) or of humans as from 1850. The main occurrences of trichinellosis were followed with particular attention in Europe (Germany, Denmark, France, etc.) and in the United States of America at the end of the XIXth century. They affected numerous domestic animal species (pigs, horses, etc.) or wildlife and humans. Germany paid the heaviest toll with regard to the disease in humans, between 1860 and 1880, with several thousands of patients and more than 500 deaths. Different trichinellosis surveillance systems were set up in the relevant countries in the 1860s. In humans, this surveillance was carried out on affected living patients by a biopsy of the biceps muscles and subsequently by an analysis of eosinophilia (1895). In animals, surveillance was for a long time solely based on postmortem examination of the muscles of the affected animals. This method was used for the first time in 1863 in Germany, and from the 1890s, on several hundreds of thousands of pigs in Europe or in the United States of America.

["porci habent squinantiam" (Ibn Sina)--a contribution to the history of swine therapeutics in the Middle Ages]

In the Middle Ages and in the early modern ages the knowledge of the diagnosis and therapy of porcine diseases mostly based on an ancient body of thought that was adopted in a more or less mutilated form. This fact is not only reflected in the books of the scholars, but also in the written records of the public animal medicine. The traditional magic medicine with its rich drug supply as well as with its prayers, blessings for the animals and emergency fires as they are called holds an important role among this public animal medicine. Only in a few cases it is possible to make a historical diagnosis due to the lack of the description of symptoms. Besides, it is difficult to judge the drugs that were used for prophylaxis and therapy with regard to the possible effects. On the basis of Latin, English and German sources from the 9th to 15th century comments are revealed on the early diagnosis, prevention and treatment of febrile general diseases and parasitic infestations of pigs. In a review it is tried to discuss the basic problems of interpretation.

Unravelling the ecology of influenza A virus

For 20 years after the influenza A virus was discovered in the early 1930s, it was believed to be almost exclusively a human virus. But in the 1950s closely related viruses were discovered in diseases of horses, pigs and birds. Subsequently influenza A viruses were found to occur frequently in many species of birds, particularly ducks, usually without causing disease. Researchers showed that human and animal strains can hybridise thus producing new strains. Such hybrids may be the cause of pandemics in man. Most pandemics have started in China or eastern Russia where many people are in intimate association with animals. This situation provides a breeding ground for new strains of influenza A virus.

[A non-specific veterinarian]

John Akkermans, who became 65 on july 4th, 1991, started his veterinary career on december 1st, 1952. He contributed in many ways to veterinary science. In the Netherlands many diseases were diagnosed by him for the first time. He had the ability to arouse the interest of many for his findings by writing papers as the sole author. But by stimulating his co-workers even more papers were published of which he was co-author and not always the first one. He was obviously able to follow the developments in veterinary science and animal husbandry without any problems and to create openings when the profession was confronted by problems. He was often involved in diseases of pigs but also in furred animals and ruminants. He was not a specialist in a single species of animal or in a single professional area, but in several fields. Not a specialist, but a more specific veterinarian in the sense that he is unique.