Has Culling Been Properly Assessed as a Valid and Justified Control Intervention Measure for Zoonotic Diseases?

No abstract available

History of ‘swine fever’ in Southern Africa

The histories of the two swine fevers in southern Africa differ widely. Classical swine fever (hog cholera) has been known in the northern hemisphere since 1830 and it is probable that early cases of ‘swine fever’ in European settlers’ pigs in southern Africa were accepted to be that disease. It was only in 1921 that the first description of African swine fever as an entity different from classical swine fever was published after the disease had been studied in settlers’ pigs in Kenya. Shortly after that, reports of African swine fever in settlers’ pigs emerged from South Africa and Angola. In South Africa, the report related to pigs in the north-eastern part of the country. Previously (in 1905 or earlier) a disease assumed to be classical swine fever caused high mortality among pigs in the Western Cape and was only eradicated in 1918. African swine fever was found over the following years to be endemic in most southern African countries. Classical swine fever, however, apart from an introduction with subsequent endemic establishment in Madagascar and a number of introductions into Mauritius, the last one in 2000, had apparently remained absent from the region until it was diagnosed in the Western and subsequently the Eastern Cape of South Africa in 2005. It was eradicated by 2007. The history of these diseases in the southern African region demonstrates their importance and their potential for spread over long distances, emphasising the need for improved management of both diseases wherever they occur.The History Committee of the South African Veterinary Associationhttp://www.jsava.co.zam2014ab201

Current status of African swine fever

African swine fever is a serious viral disease of domestic pigs and Eurasian wild boars that poses a major threat to pig production. For more than thirty years after its discovery in East Africa it was limited to eastern and southern Africa, where it is believed to have originated. The ability of the causative virus to remain viable for long periods in raw or insufciently cooked pork products has enabled it, through travel and trade, to spread widely throughout subSaharan Africa and to other continents. In the second half of the 20th century it had caused outbreaks in the majority of African countries where pigs are produced, as well as in a number of European countries, two of the Caribbean islands, and Brazil. By the turn of the century it had been eradicated from all non-African countries except the Italian island of Sardinia. In 2007 African swine fever arrived in the Republic of Georgia, and has subsequently spread insidiously into other Transcaucasian countries, Russia and some of its neighbours. In 2014 it reached the Baltic States and Poland through infected wild boars, and has become established in several wild boar populations from which it is difcult to eradicate. Most recently, in 2018 the frst outbreaks were reported in China, home to half of the world’s pig population, where it spread with unprecedented rapidity throughout China and to several other countries in the region, including the island nations of Philippines, Indonesia, Timor-Leste and Papua New Guinea. These events have posed new challenges for control, including some that parallel the situation in Africa, where poor people rely on pigs produced at subsistence level to provide for their needs and where pigs may also be socially and culturally important. The central role that humans play in the maintenance and spread of African swine fever has again been emphasised. This review describes the current status of African swine fever globally and the trends and challenges for management that face veterinarians and pig industries at all levels worldwide.https://cabiagbio.biomedcentral.compm2021Veterinary Tropical Disease

Selenium toxicosis with focal symmetrical poliomyelomalacia in postweaning pigs in South Africa

An outbreak of paralysis in finisher pigs in South Africa after ingestion of feed containing 54,581 mg/kg of selenium is described. The main and entirely consistent lesion was bilaterally symmetrical focal poliomalacia of the ventral horns of the spinal cord, which was most severe and consistent in the lumbar intumescence. Acute and subacute lesions were characterized by malacia with large numbers of gitter cells. The main features of chronic lesions were loss of neurons and gliosis. Focal degeneration and necrosis of the myocardium and skeletal muscles were also consistent, but there were fewer specific changes. Endothelial swelling, mild fibrinoid degeneration and perivascular leukocytic infiltration were present in the acute stage. Dermatitis, coronitis and hoof sloughing, usually present in more chronic cases of intoxication, were not a feature of the present outbreak, although alopecia and crusting were evident on the backs of a few pigs several weeks after the episode of intoxication. Serum- and tissue-selenium levels were elevated in the early stages after intoxication. Serum levels were nearly normal in chronic cases two months after the episode, while liver and kidney levels were still higher than normal. Higher levels were found in liver, kidney and serum than in muscle, with the highest levels in the kidney. Less than 20% of affected pigs recovered sufficiently to be marketed.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat X Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

Special issue “African swine fever and other swine viral diseases in Africa”

No abstract available.https://www.mdpi.com/journal/virusesVeterinary Tropical Disease

One hundred years of African swine fever : a tribute to R. Eustace Montgomery

One hundred years ago, the first scientific publication on “a form of swine fever” that occurred in East Africa was published by R. Eustace Montgomery in the Journal of Comparative Pathology and Therapeutics (Montgomery, 1921). Now known as African swine fever (ASF), this disease has, over the last century, been reported from all five continents and is dreaded by pig industries worldwide (Liang et al., 2020; Penrith, 2020 ). It is hoped that this tribute will contribute to ensuring that the great legacy of Montgomery's research is not forgotten.https://wileyonlinelibrary.com/journal/tbedhj2022Veterinary Tropical Disease

Classical swine fever (Hog cholera) : review of aspects relevant to control

Classical swine fever (CSF) has the ability to spread over large distances when human intervention, such as illegal swill feeding facilitates its movement. This was apparent during 2005 when CSF appeared in South Africa (SA) after an absence of 87 years. In this review various newly published developments in terms of the diagnosis of the disease and vaccination are described and applied to situations similar to SA. The role of wildlife such as feral pigs and European wild boar in the dissemination and maintenance of CSF virus are discussed and the dearth of knowledge on the potential of other wild pigs species prevalent on southern Africa noted. The modes of spread and control measures to prevent introduction as well as during outbreaks are discussed.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1865-1682/issue

With or without a vaccine-a review of complementary and alternative approaches to managing african swine fever in resource-constrained smallholder settings

The spectacular recent spread of African swine fever (ASF) in Eastern Europe and Asia has been strongly associated, as it is in the endemic areas in Africa, with free-ranging pig populations and low-biosecurity backyard pig farming. Managing the disease in wild boar populations and in circumstances where the disease in domestic pigs is largely driven by poverty is particularly challenging and may remain so even in the presence of effective vaccines. The only option currently available to prevent ASF is strict biosecurity. Among small-scale pig farmers biosecurity measures are often considered unaffordable or impossible to implement. However, as outbreaks of ASF are also unaffordable, the adoption of basic biosecurity measures is imperative to achieve control and prevent losses. Biosecurity measures can be adapted to fit smallholder contexts, culture and costs. A longerterm approach that could prove valuable particularly for free-ranging pig populations would be exploitation of innate resistance to the virus, which is fully effective in wild African suids and has been observed in some domestic pig populations in areas of prolonged endemicity. We explore available options for preventing ASF in terms of feasibility, practicality and affordability among domestic pig populations that are at greatest risk of exposure to ASF.http://www.mdpi.com/journal/vaccinespm2022Veterinary Tropical DiseasesZoology and Entomolog