Rabies is a viral disease that affects the central nervous system and is almost always fatal once symptoms appear. It is primarily spread through the bite of an infected animal, most commonly dogs. Rabies has been feared throughout history due to its lethality and the horrific symptoms it causes. A question that often arises regarding rabies is whether the virus can spread from a dead body to living humans or animals. In this article, we will examine what rabies is, how it spreads, whether rabies can spread after death, and the implications of postmortem rabies transmission.
What is Rabies?
Rabies is caused by a virus in the genus Lyssavirus. There are multiple strains of the rabies virus, with the most common being the “classical” rabies virus seen in dogs, bats, raccoons, skunks, and foxes. Other strains include Lagos bat virus and Mokola virus. The rabies virus has a distinctive bullet shape and attacks the nervous system, ultimately leading to brain dysfunction, delirium, and death.
Some key facts about rabies:
- Rabies causes tens of thousands of deaths per year globally, with 95% of cases occurring in Africa and Asia.
- Nearly all human rabies cases result from dog bites.
- Bats are the most common source of human rabies in the Americas.
- Rabies has the highest mortality rate of any infectious disease – almost 100% in unvaccinated humans showing symptoms.
- Rabies is transmitted through infected saliva that enters the body, usually via a bite.
- The time between rabies infection and symptom onset is typically 1-3 months but can vary from under a week to over a year.
- Early rabies symptoms include fever, headache, weakness. As the disease progresses, there is neurological dysfunction, anxiety, confusion, hallucinations, hypersalivation, and hydrophobia (fear of water).
- There is no cure for rabies once symptoms appear, but preventive vaccination administered promptly after a suspected exposure can prevent the onset of rabies.
So in summary, rabies is an ancient viral disease that infects the nervous system and almost always causes a horrific death once symptoms start. It spreads via saliva, most often through animal bites. Rabies remains a persistent threat to humans, particularly in the developing world. This brings us to the key question…
How Does Rabies Spread Between Living Hosts?
To understand if rabies can spread after death, it’s important to first consider how rabies spreads among the living.
The vast majority of rabies transmission between humans and animals occurs by direct contact with infected saliva through bites, scratches, or mucous membrane exposure. When an infected animal bites another animal or person, the virus in the saliva enters the wound and travels to the peripheral nerves. The virus then travels to the central nervous system, where it rapidly causes inflammation of the brain and spinal cord.
Animal to Animal
Among animal populations like dogs, wild canids, and bats, rabies spreads through biting and saliva. When an infected animal bites another animal, the virus in the saliva infects the bitten animal. Skunks, raccoons, foxes, and other wild mammals are susceptible to rabies. Bats transmit several strains of the rabies virus. Infected bats can spread the virus to humans and other animals through their bites.
Animal to Human
Humans most often get infected with rabies through animal bites. Dogs account for up to 99% of human rabies cases globally. Cats, bats, raccoons, skunks, and foxes also transmit rabies to humans. Human-to-human transmission is extremely rare.
After a bite from a rabid animal, the rabies virus infects peripheral nerves and travels to the central nervous system. The incubation period is usually 1-3 months but can vary greatly. Once symptoms appear, the infection is nearly always fatal.
For rabies spread between living animals and humans, direct contact with infected saliva through bites, scratches, or mucous membrane exposure is necessary. The virus cannot infect through intact skin.
Can Rabies Spread from a Dead Body?
This brings us to the key question – can rabies spread from someone who has died of rabies to another person?
The short answer is no. There is no evidence that the rabies virus can be transmitted from a dead body.
According to the WHO, there are no documented cases of rabies being transmitted from a dead body to humans. Multiple studies have shown that the rabies virus cannot survive long outside of a living host.
Here are reasons why rabies does not spread from those who have died of the disease:
Lack of Active Virus
For rabies transmission to occur from a dead body, active, intact rabies virus would need to be present in large enough amounts.
However, by the time a rabies patient dies, they have very little active virus left in their body. This is because the virus has already heavily infected the brain and caused severe damage.
One study tested brain samples of 55 rabies patients after death and found no intact rabies virus, only fragments.
Virus Cannot Survive Long Outside Host
Additionally, once a rabies patient dies, the virus begins to degrade and cannot survive for long outside of a host.
Rabies virus becomes inactivated outside of a living body due to factors like oxygen, ultraviolet radiation, microbial activity, and dryness.
One study found the rabies virus loses 90% of infectivity within an hour of drying. The virus only remains viable for short periods in very cold conditions.
No Biting Can Occur
For rabies transmission to occur, infected saliva must be introduced into a fresh wound. A dead body cannot bite or scratch to transmit saliva.
Proper handling and burial procedures eliminate any theoretical risk of contact with saliva or neural tissue.
Some key points:
- No scientifically confirmed case of rabies spread from a dead body exists.
- The rabies virus degrades rapidly after death and cannot survive for long outside a living host.
- Biting or scratching is necessary to transmit rabies, which a dead body cannot do.
- Standard precautions eliminate any theoretical risk during burial procedures.
So while rabies patients have high levels of virus before death, the virus does not persist or retain infectivity in the body after death. This makes transmission from a dead body highly unlikely.
Proper Handling of Dead Bodies with Rabies
Despite the lack of evidence for postmortem rabies transmission, caution should still be taken when handling bodies of those who die of rabies.
The WHO and CDC recommend common sense precautions to avoid contact with neural tissue and bodily fluids:
- Place the body in two sealed body bags.
- Wear gloves, face protection if necessary.
- Disinfect anything contaminated with bodily fluids.
- Do not store on ice or embalm, as low temperatures may preserve virus.
- Cremate or bury remains promptly.
By following basic hygienic precautions, mortuary and burial staff can work safely on rabies-infected bodies. Prompt and safe burial helps eliminate any hypothetical risk.
Prevention of Rabies Transmission
While rabies is close to 100% fatal once symptoms manifest, there are very effective preventive measures:
- Animal vaccines – Vaccinating dogs, cats, ferrets against rabies is key to reducing transmission. Oral wildlife vaccines can also immunize wild mammals like raccoons and foxes.
- Bite prevention – Avoiding contact with all wild mammals and stray animals reduces bite risk. Supervising pets also limits potential exposures.
- Bite wound washing – Thoroughly washing bite wounds with soap and water for 15 minutes immediately after a bite can help flush out virus and prevent infection.
- Human vaccines – Pre-exposure and post-exposure rabies vaccines are highly effective in preventing disease in humans after potential contact with rabid saliva.
Widespread animal vaccination, public awareness, and proper post-bite care are key strategies for lowering rabies deaths worldwide.
Conclusion
In conclusion, there is no scientific evidence showing that rabies can spread from someone who has died of the disease to another person. The rabies virus cannot survive for long outside of a living host. Biting and viral transmission cannot occur from a dead body. Proper precautions are still recommended when handling remains to avoid contact with bodily fluids. While rabies continues to kill many worldwide, the disease ultimately stops with the death of each infected individual. Our best defense remains widespread vaccination of domestic animals and proper care of bite wounds in humans, along with prompt burial practices for those dead of this ancient affliction.