Rinderpest

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Rinderpest virus

Group:	Group V ((-)ssRNA)
Order:	Mononegavirales
Family:	Paramyxoviridae
Genus:	Morbillivirus
Species:	Rinderpest virus

Rinderpest is an infectious viral disease of cattle, domestic buffalo, and some species of wildlife. It is commonly referred to as cattle plague or steppe murrain. The disease is characterized by fever, oral erosions, diarrhea, lymphoid necrosis, and high mortality. The term Rinderpest is adapted from German, meaning cattle-plague.

1 The virus
2 The disease
3 History
4 Eradication
5 References
6 External links

[edit] The virus

As it is a Morbillivirus, the rinderpest virus (RPV) is closely related to the measles and canine distemper viruses.^[1] Despite its extreme lethality, the germ is particularly fragile and is quickly inactivated by heat, desiccation and sunlight.^[2]

[edit] The disease

Death rates during outbreaks are usually extremely high, approaching 100%.^[3] The disease is mainly spread by direct contact and by drinking contaminated water, although it can also be transmitted by air.^[4]

Initial symptoms include fever, loss of appetite, and nasal and eye discharges. Subsequently, irregular erosions appear in the mouth, the lining of the nose, and the genital tract.^[3] Acute diarrhoea, preceded by constipation, is a common feature as well.^[4] Most animals die 6-12 days after the onset of these clinical signs.^[3]

[edit] History

[edit] Epidemics

Cattle plagues recurred throughout history, often accompanying wars and military campaigns. It hit Europe especially hard in the 18th century, with three long pandemics which, although varying in intensity and duration from region to region, took place in the periods of 1709-1720, 1742-1760, and 1768-1786^[5]. Later in history, an outbreak in the 1890s killed 80 to 90 percent of all cattle in Southern Africa, as well as the Horn of Africa. Sir Arnold Theiler was instrumental in developing a vaccine that curbed the epidemic. More recently, another rinderpest outbreak that raged across much of Africa in 1982-84 is estimated to have cost at least US$500 million in stock losses.

[edit] Inoculation

In the early 18th century, the disease was seen as similar to smallpox, due to its analogous symptoms. The personal physician of the Pope, Giovanni Maria Lancisi, recommended the slaughter of all infected and exposed animals. This policy was not very popular and used only sparingly in the first part of the century. Later, it was used successfully in several countries, although it was sometimes seen as too costly or drastic, and depended on a strong central authority to be effected (something which was notably lacking in the Dutch Republic). Because of these downsides, numerous attempts were made to inoculate animals against the disease. These attempts met with varying success, but the procedure was not widely used and was no longer practised at all in 19th-century Western or Central Europe. Rinderpest was an immense problem, but inoculation was not a valid solution: In many cases, it caused too many losses. Even more importantly, it perpetuated the circulation of the virus in the cattle population. The pioneers of inoculation did contribute significantly to our knowledge about infectious diseases. Their experiments confirmed the concepts of those who saw infectious diseases as caused by specific agents, and were the first to recognise maternally derived immunity^[1].

[edit] Early English experimentation

The first written report of rinderpest inoculation was published in a letter signed 'T.S.' in the November 1754 issue of Gentleman's Magazine,^[1] a widely-read journal which also supported the progress of smallpox inoculation. This letter reported that a Mr. Dobsen had inoculated his cattle and had thus preserved nine out of ten of them, although this was retracted in the next issue as it was apparently a Sir William St. Quintin who had done the inoculating (this was done by placing bits of material previously dipped in morbid discharge into an incision made in the dewlap of the animal). These letters encouraged further application of inoculation in the fight against diseases. The first inoculation against measles was made three years after their publication.^[1]

From early 1755 onwards, experiments were taking place in the Netherlands as well, results of which were also published in Gentleman's Magazine. As in England, the disease was seen as analogous with smallpox. While these experiments were reasonably successful, they did not have a significant impact: The total number of inoculations in England appears to have been very limited, and after 1780 the English interest in inoculation disappeared almost entirely.^[1] Almost all further experimentation was done in the Netherlands, Northern Germany and Denmark.

[edit] Further trials in the Netherlands

Due to a very severe outbreak at the end of the 1760s, some of the biggest names in Dutch medicine became involved in the struggle against the disease. Several independent trials were begun, most notably by Pieter Camper in Groningen and Friesland. The results of his experiment in Friesland were encouraging, but they proved to be the exception: testing by others in the provinces of Utrecht, Leeuwarden and Friesland obtained disastrous results. As a result, the Friesian authorities concluded in 1769 that the cause of rinderpest was God's displeasure with the sinful behaviour of the Friesian people, and proclaimed 15 November a day of fasting and prayer. Interest in inoculation declined sharply across the country.^[1]

In this climate of discouragement and scepticism, Geert Reinders, a farmer in the province of Groningen and a self-taught man, decided to continue the experiments. He collaborated with Wijnold Munniks, who had supervised earlier trials. They tried different inoculation procedures and a variety of treatments to lighten the symptoms, all of them without significant effect. Although they were not able to perfect the inoculation procedure, they did make some useful observations.^[1]

Reinders resumed his experiments in 1774, concentrating on the inoculation of calves from cows that had recovered from rinderpest. He was probably the first to make practical use of maternally derived immunity^[1]. The detailed results of his trials were published in 1776 and reprinted in 1777. His inoculation procedure did not differ much from what had been used previously, except for the use of three separate inoculations at an early age. This produced far better results, and the publication of his work renewed interest in inoculation. For the period of 1777 to 1781, 89% of inoculated animals survived, compared to a 29% survival rate after natural infection.^[1]

In the Netherlands too, interest in rinderpest inoculation declined in the 1780s because the disease itself decreased in intensity.

[edit] In other countries

Apart from the Dutch republic, the only other regions where inoculation was used to any significant level were Northern Germany and Denmark. Experiments started in Mecklenburg during the epizootic of the late 1770s. 'Insurance companies' were created which provided inoculation in special 'institutes'. Although these were private initiatives, they were created with full encouragement from the authorities. Even though neighbouring states followed this practice with interest, the practice never caught on outside of Mecklenburg: many were still opposed to inoculation^[1].

While some experimentation occurred in other countries (most extensively in Denmark), in the majority of European countries the struggle against the disease was based on stomping it out. Sometimes this could be done with minimal sacrifices, at other times, it required slaughter at a massive scale^[1].

[edit] In ethnography

In his classic study of the Nuer of southern Sudan, E. E. Evans-Pritchard suggests that rinderpest might have affected the Nuer's social organization prior to and during the 1930s. Since the Nuer were pastoralists, much of their livelihood was based on cattle husbandry, and bride-prices were paid in cattle; prices may have changed as a result of cattle depletion. Rinderpest might also have increased dependence on horticulture among the Nuer.^[6]

[edit] Vaccination

Dr. Walter Plowright was awarded the World Food Prize in 1999, for developing a vaccine against rinderpest. The Plowright vaccine was developed to the RBOK of the rinderpest virus.^[7] The FAO predicts that with vaccination the cattle plague will be eradicated by 2010^[8].

[edit] Eradication

In 2008, scientists involved in rinderpest eradication efforts believe there is a good chance that rinderpest may join smallpox as officially "wiped off the face of the planet".^[9] Prior efforts, such as the Joint Project 15 in 1962 were very successfull, but ended prematurely and the disease made dramatic comebacks. The current Global Rinderpest Eradication Programme, run by the U.N. Food and Agriculture Organization, has been active since 1993, and set its initial goals for eradicating the disease by 2004.