Seal distemper outbreak - 2002
In August 2002, the washed up bodies of a few harbour seals along the Wash coastline marked the onset of an outbreak of distemper. The Phocine (seal) Distemper Virus (PDV) had last been seen in the UK in 1988 when it claimed the lives of over 18,000 animals. Now, nearly fifteen years later, it appeared that the deadly and highly infectious virus was back and once more threatening the seal populations of East Anglia.
The virus can affect both the common and the grey seals, although common seals are far more susceptible to the disease. The sight of these large animals, which can grow up to 2.3 m long and weigh up to 300 kg, lying inert along our shores has been an upsetting sight for many seaside visitors over the past year.
In common with the outbreak of 1988, the worst affected areas of the UK are Suffolk and the Wash; seal numbers in the Wash halved during the previous outbreak. The virus originated in Denmark and spread across the North Sea over a period of a few months. It spreads between seals in the same way as the common cold spreads between people. Its presence was confirmed by post mortems carried out at the RSPCA wildlife hospital in Norfolk by Ian Robinson. By the end of September 2002, a total of nearly 800 dead seals had been found, 700 of these had been washed up along the UK coastline.
The virus is similar to Canine Distemper and is capable of infecting dogs that are not up to date with their vaccinations. Infected animals may show symptoms such as coughing, lethargy and disorientation. Ill seals are also unable to dive for food and the effect on their immune systems can make them more prone to catching other diseases. There is no current treatment for the disease and although vaccines are available, these can cause a great deal of stress to the seals. Although it is not known exactly what causes the disease, it is thought that it may be linked to increased coastal pollution.
The disease cannot be transmitted to human beings or to fish and birds. However, the carcasses of the seals may harbour other bacterial infections and should be avoided by people and reported to DEFRA (Department for the Environment, Food and Rural Affairs).
The population of seals had only just recovered from the 1988 outbreak and the impact of the 2002 virus hit seal populations hard, especially as the height of the outbreak occurred during the breeding season. This meant that a lot of seal pups and pregnant seals died. Immunity to the disease is low and only around 20% of the infected animals recover.
The virus has caused great public concern since the start of the outbreak; from people concerned about the fate of the local seal population to those worried about public health. However, the work carried out by DEFRA in conjunction with a variety of voluntary organisations has helped to allay many fears. The beaches that have been most affected have all had signs erected on them providing information about the virus, what to do if you find a dead or dying seal and a helpline number. The excellent public response from the people of East Anglia to these notices has helped a great deal towards coping with and assessing the full impact of the outbreak.
The Institute of Zoology have also greatly contributed to the control of the disease. As part of a £250,000 project, they have been surveying the coastline for areas with ill seals and keeping welfare organisations up to date about the spread of the disease. They have also been carrying out postmortems, assessing how susceptible the East Anglian seals are to the disease and forecasting seal mortality rates.
In addition, the RSPCA has been central in trying to care for sick animals and helping diagnose the disease at the Norfolk wildlife hospital. Extra RSPCA staff have been called in to help collect ill seals and treat them in the hospital. The hospital was established after the 1988 epidemic specifically to deal with another outbreak of PDV. The work it has carried out since August of last year has been of critical importance and the existence of such a facility in our area has been crucial in effectively dealing with this crisis.
Presently, the seal populations are starting to recover and the worst of the crisis is over. By February, 2003, The number of dead seals found along our coastline had dropped to only 74, bringing the total deaths since the start of the outbreak up to 3990. Of these cases, 2810 were along the British coastline, mainly in East Anglia. Since February 2003, there has been a steady decline in the number of seal deaths suggesting that the outbreak is under control and coming to a close. Despite peoples worst fears, the outbreak has not been as severe as in 1988, perhaps due to some of the seals having better immunity than 14 years ago. Despite this, many animals have died and it will take many years until the numbers of seals increase to their former levels.
However, as we walk on our beaches today, perhaps glimpsing some seals playing in the waters, we can only hope that the population recovers well and that the surviving seals have developed immunity to the disease, in case it should strike again. We should also be thankful to all the work carried out by DEFRA, the RSPCA, the Institute of Zoology and the help and corporation of the general public in combating the disease and caring for the sick animals. Perhaps now the fate of the seals along our coastline is a brighter prospect than it has been over the past year and visitors to our shores can once more start to enjoy watching the healthy seals enjoying the coastal waters of East Anglia.