Almost all human deaths caused by rabies originate from Asia and Africa. There are an estimated 55,000 human deaths annually from rabies worldwide.[1]
The English Channel, dog licensing, killing of stray dogs, muzzling and other measures contributed to the elimination of rabies from the United Kingdom in the early 20th century. More recently, large-scale vaccination of cats, dogs and ferrets has been successful in combatting rabies in some developed countries.
Rabies is a zoonotic disease, caused by the rabies virus. The rabies virus, a member of the Lyssavirus genus of the Rhabdoviridae family, survives in a diverse variety of animal reservoirs, including bats, monkeys, raccoons, foxes, skunks, wolves, coyotes, dogs, mongoose, weasels, cats, cattle and other domestic farm animals, groundhogs, bears and other wild carnivores. However, in Asia, parts of America and large parts of Africa, dogs remain the principal host. Mandatory vaccination of animals is less effective in rural areas. Especially in developing countries, pets may not be privately kept and their destruction may be unacceptable. Oral vaccines can be safely distributed in baits, and this has successfully reduced rabies in rural areas of Canada, France and the United States and elsewhere, like in Montreal where baits are successfully used among raccoons in the Mount Royal park area.
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One of the sources of recent flourishing of rabies in East Asia is the pet boom. China introduced in the city of Beijing the "one-dog policy" in November 2006, to control the problem.[2]
India has been reported as having the highest rate of human rabies in the world primarily due to stray dogs. Because of the recent decline of vultures due to acute poisoning primarily due to the anti-inflammatory diclofenac, animal carcasses are no longer being sufficiently cleared--as the vultures were in competition with feral dogs for these carcasses as food-source, the dogs breed unfettered and produce a larger pool of carriers for the rabies virus.[3]
The island of Bali in Indonesia has been undergoing a severe outbreak of canine rabies since 2008, that has also killed about 78 humans as of late September 2010.[4] Unlike predominantly Muslim parts of Indonesia, in Bali many dogs are kept as pets and strays are tolerated in residential areas.[5] Efforts are under way to vaccinate pets and strays, as well as selective culling of some strays,[4] to control the outbreak. As Bali is a popular tourist destination, visitors are advised to consider rabies vaccinations before going there, if they will be touching animals.[6]
Approximately 24 000 people die annually in Africa[7] a rate of approximately 23 per million population.
In South Africa between 10 to 30 cases of human rabies are confirmed every year and it is particularly widespread in the north-eastern regions of the Eastern Cape, the eastern and south-eastern areas of Mpumalanga, northern Limpopo and KwaZulu-Natal.[8] Dogs are the main vector (especially in the east of the country)for the disease but also wildlife including the bat-eared fox, yellow mongoose and black-backed jackal.[9] The death rate of 13 per annum over the decade 2001-2010 [10] is a rate of approximately 0.26 per million population. This is approximately 30 times the rate in the United States but 1/90th of the African average. The number of cases per province over the last decade are as follows:
| Year | Eastern Cape | Free-state | Gauteng | KwaZulu Natal | Limpopo | Mpuma-langa | Northern Cape | North-West | Western Cape | South Africa |
| 2001 | 6 | 1 | 7 | |||||||
| 2002 | 8 | 8 | ||||||||
| 2003 | 1 | 9 | 1 | 11 | ||||||
| 2004 | 7 | 1 | 8 | |||||||
| 2005 | 3 | 1 | 3 | 7 | ||||||
| 2006 | 4 | 4 | 22 | 1 | 31 | |||||
| 2007 | 6 | 8 | 1 | 15 | ||||||
| 2008 | 8 | 5 | 3 | 1 | 17 | |||||
| 2009 | 7 | 4 | 2 | 2 | 15 | |||||
| 2010 | 2 | 1 | 3 | 3 | 1 | 10 | ||||
| 2001 to 2010 | 31 | 1 | 1 | 57 | 31 | 6 | 0 | 2 | 0 | 129 |
| Average | 3.1 | 0.1 | 0.1 | 5.7 | 3.1 | 0.6 | 0 | 0.2 | 0 | 12.9 |
Rabies was once rare in the United States outside the Southern states, but raccoons in the mid-Atlantic and northeast United States have been suffering from a rabies epidemic since the 1970s, that is now moving westwards into Ohio.[11]
The particular variant of the virus has been identified in the southeastern United States raccoon population since the 1950s, and is believed to have traveled to the northeast as the result of infected raccoons being among those caught and transported from the southeast to the northeast by human hunters attempting to replenish the declining northeast raccoon population.[12] As a result, urban residents of these areas have become more wary of the large but normally unseen urban raccoon population. It has become the common assumption that any raccoon seen diurnally is infected; certainly the reported behavior of most such animals appears to show some sort of illness, and necropsies can confirm rabies. Whether as a result of increased vigilance or only the common human avoidance reaction to any other animal not normally seen, such as a raccoon, there has only been one documented human rabies case as a result of this variant.[13][14] This does not include, however, the greatly increasing rate of prophylactic rabies treatments in cases of possible exposure, which numbered fewer than one hundred humans annually in the state of New York before 1990, for instance, but rose to approximately ten thousand annually between 1990 and 1995. At approximately $1,500 per course of treatment, this represents a considerable public health expenditure. Raccoons do constitute approximately 50% of the approximately eight thousand documented non-human rabies cases in the United States.[15] Domestic animals constitute only 8% of rabies cases, but are increasing at a rapid rate.[15]
In the midwestern United States, skunks are the primary carriers of rabies, composing 134 of the 237 documented non-human cases in 1996. The most widely distributed reservoir of rabies in the United States, however, and the source of most human cases in the U.S., are bats. Nineteen of the twenty-two human rabies cases documented in the United States between 1980 and 1997 have been identified genetically as bat rabies. In many cases, victims are not even aware of having been bitten by a bat, assuming that a small puncture wound found after the fact was the bite of an insect or spider; in some cases, no wound at all can be found, leading to the hypothesis that in some cases the virus can be contracted via inhaling airborne aerosols from the vicinity of bats. For instance, the Centers for Disease Control and Prevention (CDC) warned on May 9, 1997, that a woman who died in October, 1996 in Cumberland County, Kentucky and a man who died in December, 1996 in Missoula County, Montana were both infected with a rabies strain found in silver-haired bats; although bats were found living in the chimney of the woman's home and near the man's workplace, neither victim could remember having had any contact with them.[16] Similar reports among spelunkers led to experimental demonstration in animals.[17] This inability to recognize a potential infection, in contrast to a bite from a dog or raccoon, leads to a lack of proper prophylactic treatment, and is the cause of the high mortality rate for bat bites.
On September 7, 2007, rabies expert Dr. Charles Rupprecht of Atlanta-based U.S. Centers for Disease Control and Prevention said that canine rabies had disappeared from the United States. Rupprecht emphasized that the disappearance of the canine-specific strain of rabies virus in the US does not eliminate the need for dog rabies vaccination as dogs can still become infected from exposure to wildlife.[18]
Several countries in Europe have been designated rabies-free jurisdictions: Austria, United Kingdom, Republic of Ireland, Belgium, the Netherlands, Luxembourg, France, Switzerland, Portugal, Italy, Spain, Greece, Malta, Germany, Denmark, Norway, Sweden, Finland, and Iceland.[19]
Nine deaths from rabies were reported in Germany between 1981 and 2005. Two were caused by animal bites within Germany (one fox, one dog), and four were acquired abroad. In the remaining three cases, the source was a transplant from a donor who had died of rabies.[20] On 28th September 2008, the World Organisation for Animal Health declared Germany as free of rabies.[21]
The rabies virus was eradicated from the UK early in the 20th century.[20]
Since 1902, there have been 26 deaths in the UK from rabies (excluding the European bat lyssavirus 2 case discussed below).[20][22] A case in 1902 occurred shortly before the eradication of rabies from the UK, and no details were recorded for a case in 1919.[20] All other cases of rabies caused by rabies virus acquired the infection while abroad. Sixteen cases (62%) involved infections acquired in India, Pakistan or Bangladesh.[20]
Since 2000, four deaths from rabies have occurred; none of these cases had received any post-exposure prophylactic treatment. In 2001, there were two deaths from infections acquired in Nigeria and the Philippines. One death occurred in 2005 from an infection acquired by a dog bite in Goa (western India).[20][23] The most recent case was a woman who died on 6 January 2009 in Belfast. She is believed to have been infected in South Africa, probably from being scratched by a dog.[24][25][26][27] Prior to this, the last reported human case of the disease in Northern Ireland was in 1938.[26][27]
A rabies-like lyssavirus, called European bat lyssavirus 2, was identified in bats in 2003.[23] There has been one case of a bite from an infected bat, but the victim showed no symptoms of the virus and was vaccinated quickly as a precaution. In 2002, there was a fatal case in a bat handler involving infection with European bat lyssavirus 2; infection was probably acquired from a bite from a bat in Scotland.[20][23]
The Netherlands has been designated rabies-free since 1923, Belgium since 2008. Isolated cases of rabies involving illegally smuggled pets from Africa, as well as infected animals crossing the German and French borders do occur.[28]
Since 1948, 29 people have been reported dead from rabies in Israel. The last death was in 2003, when a 58-year-old Bedouin woman was bitten by a cat and became infected. She was not inoculated and later died.[29]
Many island territories—such as the United Kingdom, Ireland, Taiwan, Japan, Hawaii, Mauritius, Barbados, and Guam—are free of rabies, although there may be a very low prevalence of rabies among bats in the UK (see separate section).
New Zealand and Australia have never had rabies.[30] However, in Australia, the Australian bat lyssavirus occurs normally in both insectivorous and fruit-eating bats (flying foxes) from most mainland states. Scientists believe it is present in bat populations throughout the range of flying foxes in Australia.
Germany was declared to be free of rabies by the World Organisation for Animal Health on 28th November 2008.[31]
