Rinderpest: gone, but not forgotten – yet.

Rinderpest virus infects cattle, buffalo and several species of antelope among other animals: it is a member of the genus Morbillivirus,family Paramyxoviridae, and is related to measles and mumps viruses in humans, distemper virus in dogs, and a variety of relatively newly-described viruses in marine mammals.  It also almost certainly gave rise to measles virus sometime around the 11th-12th centuries CE, as an originally zoonotic infection – sourced in domestic animals – took root in humans and began to be passed around (see MicrobiologyBytes).

Electron micrograph of a morbillivirus particle showing the membrane, matrix, and inner helical nucleocapsid. Image by LM Stannard

The ICTVdB generic description of morbilliviruses is as follows:

Virions consist of an envelope and a nucleocapsid. Virus capsid is enveloped. Virions are spherical to pleomorphic; filamentous and other forms are common. Virions measure (60-)150-250(-300) nm in diameter; 1000-10000 nm in length. Surface projections are distinctive spikes of haemagglutinin (H) and fusion (F) glycoproteins covering evenly the surface. Surface projections are 9-15 nm long; spaced 7-10 nm apart. Capsid/nucleocapsid is elongated with helical symmetry. The nucleocapsid is filamentous with a length of 600-800(-1000) nm and a width of 18 nm. Pitch of helix is 5.5 nm.

The Mr of the genome constitutes 0.5% of the virion by weight. The genome is not segmented and contains a single molecule of linear negative-sense, single-stranded RNA. Virions may also contain occasionally a positive sense single-stranded copy of the genome (thus, partial self-annealing of extracted RNA may occur). The complete genome is 15200-15900 nucleotides long.

Wikipedia describes rinderpest virus as “…an infectious viral disease of cattle, domestic buffalo, and some species of wildlife. The disease was characterized by fever, oral erosions, diarrhea, lymphoid necrosis, and high mortality.”   And: “The term Rinderpest is taken from German, and means cattle-plague.”

The Food and Agriculture Organisation (FAO) has a Division of Animal Production and Health: their web site details a campaign known as the Global Rinderpest Eradication Programme (GREP), which has been going since 1994.

With very little fanfare, I might point out: as a practicing teaching virologist, I was totally unaware of it.  Anyway: they state that:

Rinderpest has been a dreaded cattle disease for millennia, causing massive losses to livestock and wildlife on three continents. This deadly cattle plague triggered several famines and caused the loss of draught animal power in agricultural communities in the 18th, 19th and 20th centuries.

…which is a little of an understatement: Wikipedia tells us that

“Cattle plagues recurred throughout history, often accompanying wars and military campaigns. They 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. There was a major outbreak covering the whole of Britain in 1865/66.”

“Later in history, an outbreak in the 1890s killed 80 to 90 percent of all cattle in Southern Africa, as well as in the Horn of Africa [and resulted in the deaths of many thousands of people who depended on them]. Sir Arnold Theiler was instrumental in developing a vaccine that curbed the epidemic. [my insert / emphasis] More recently, a rinderpest outbreak that raged across much of Africa in 1982–1984 cost at least an estimated US$500 million in stock losses”.

When commenting on the significance of the achievement, John Anderson, the head of the FAO, described GREP’s announcement that Rinderpest had been eradicated as:

The biggest achievement of veterinary history“.

The 19th century southern African outbreak was devastating enough that people still remember it as a legendary time of hardship – and then there was the 1980s outbreak.  Another South African interest in rinderpest is that the legendary Sir Arnold Theiler had a hand in making a vaccine: he did this around the turn of the 20th century, by simultaneously injecting animals with blood from an infected animal and antiserum from a recovered animal: this protected animals for long enough to allow their immune systems to respond to the virus – but was rather risky, even though it was used for several decades.

In the 1920s J. T. Edwards in what is now the Indian Veterinary Research Institute serially passaged the virus in goats: after 600 passages it no longer caused disease, but elicited lifelong immunity. However, it could still cause disease in immunosuppressed cattle.

In 1962, Walter Plowright and R.D. Ferris used tissue culture to develop a live-attenuated vaccine grown in calf kidney cells.  Virus that had been passaged 90 times conferred immunity without disease even in immunosuppressed cattle, was stable, and did not spread between animals.  This vaccine was the one that allowed the prospect of eradicating the virus, and earned Plowright a World Food Prize in 1999.

But a memory may be all rinderpest is any more – as the GREP site says the following:

“The last known rinderpest outbreak in the world was reported in 2001 (Kenya). Based on the above-mentioned investigations, FAO is confident that all rinderpest virus lineages will prove to be extinct.”

This was also announced via the BBC on the 14th October, 2010.  They said:

The eradication of the virus has been described as the biggest achievement in veterinary history and one which will save the lives and livelihoods of millions of the poorest people in the world.

And the significant bit:

If confirmed, rinderpest would become only the second viral disease – after smallpox – to have been eliminated by humans.

Let us reiterate that: only the second viral disease, ever, to have been eliminated.  And how was this possible?  Unlike smallpox, which has only humans as a natural and reservoir host (although it almost certainly also got into us from animals), rinderpest attacked a wider range of hosts.  However, it seemed mainly to have a reservoir in domesticated cattle, and it did not have an arthropod vector; moreover, the vaccine was cheap and effective.

This is momentous news: we may well have succeeded in ridding the planet of what has been a very significant disease of livestock and of wild animals, which has caused untold agricultural loss throughout recorded history, and which has resulted in enormous human hardship as well.  We have also made a natural species go extinct – but it won’t be missed.  Like smallpox, it was completely sequenced some time ago, so we could theoretically recreate it if we ever needed to.

From GREP:

Though the effort to eradicate rinderpest has encountered many obstacles over the past several decades, the disease remains undetected in the field since 2001. As of mid 2010, FAO is confident that the rinderpest virus has been eliminated from Europe, Asia, Middle East, Arabian Peninsula, and Africa. This has been a remarkable achievement for veterinary science, evidence of the commitment of numerous countries, and a victory for the international community.

Amen.  However – it’s not quite time to celebrate as the certification is only planned for 2011.

And now for mumps, and measles too.

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2 Responses to “Rinderpest: gone, but not forgotten – yet.”

  1. Deliberate extinction: now for Number 3 « ViroBlogy Says:

    [...] have written previously about the Rinderpest virus eradication campaign – and now it appears as though the final nail has in fact been hammered into the [...]

  2. Moratorium on using live rinderpest virus lifted for approved research | ViroBlogy Says:

    […] of wild rinderpest virus, which I have covered in some detail here on ViroBlogy: see here (http://rybicki.wordpress.com/2010/11/05/rinderpest-gone-but-not-forgotten-yet/) and here […]

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