Quick answer
It is extremely rare, but possible in some cases to get rabies without a wound. Rabies is typically transmitted through bites or scratches from infected animals that introduce the virus into the body. However, rabies can also be transmitted if infected saliva or nervous tissue comes into direct contact with mucous membranes like the eyes, nose, or mouth. This can happen through breathing in aerosolized saliva or contact with mucous membranes. Overall, non-bite transmission is very rare and most cases involve a bite or scratch wound.
How is rabies transmitted?
Rabies is caused by a virus that infects the central nervous system. It is primarily transmitted through the bite or scratch of an infected animal. The main routes of rabies transmission are:
- Bite wounds: Bites from infected animals introduce the virus through saliva into muscle and nerve tissue.
- Scratches: Scratches can also transmit rabies if saliva from an infected animal enters the wound.
- Mucous membrane contact: The virus can be transmitted through contact with mucous membranes in the eyes, nose, or mouth. This occurs rarely if infected saliva directly contacts these membranes.
- Aerosol transmission: In rare cases, rabies can be contracted by inhaling aerosolized virus particles, like in bat caves.
- Organ transplants: There are rare cases of rabies transmitted through corneal transplants and organ transplants from infected donors.
The vast majority of rabies cases (around 99%) are caused by bites from infected animals like dogs, bats, raccoons, foxes, and skunks. However, because the virus is present in saliva, contact through scratches or mucous membranes is also possible.
Can you get rabies without a bite or scratch?
While extremely rare, it is possible to contract rabies without a recognized bite or scratch wound. This occurs through contact of infected saliva or tissue with mucous membranes. Some examples include:
- Infected saliva getting into the eyes, nose, or mouth
- Inhaling aerosolized rabies virus, like in caves with infected bats
- Contact between infected tissue and open wounds or mucous membranes
- Laboratory accidents where the live virus comes into contact with mucous membranes
- Organ or corneal transplants from an infected donor
Even though bites account for the vast majority of rabies transmissions, bathandlers, veterinarians, laboratory workers and cave explorers are at higher risk if saliva, nervous tissue, or aerosolized virus contacts their mucous membranes when handling infected animals. There are very rare reports of people developing rabies this way, but it is extremely unlikely in normal circumstances.
What are the risks of non-bite transmission?
Non-bite transmission of rabies accounts for less than 1% of reported rabies cases worldwide. Some key points about risks:
- Bats account for most of the rare non-bite cases due to exposures in caves or during handling.
- Aerosol transmission is only documented in unique situations, like heavily populated bat caves.
- Contact with mucous membranes of the eyes, nose or mouth is the main route of non-bite transmission.
- Casual contact with blood, urine or feces from a rabid animal does not transmit rabies.
- Petting or handling an animal with rabies also does not transmit the virus without bites or tissue contact.
- In developing countries, most non-bite cases followed high-risk exposures during surgery using infected instruments.
For the general public interacting with household pets, neighborhood animals or wildlife, bites and scratches present the main risk for rabies. Non-bite transmission is extremely rare unless handling very high-risk animals like bats or in laboratory exposures.
Can you get rabies from eating infected meat?
Eating meat or animal products from a rabid animal does not transmit rabies. The rabies virus is destroyed by digestion and cannot infect a person through the gastrointestinal tract.
There are no known cases of rabies transmitted through consuming meat, milk, or any other products derived from infected animals. The virus must reach nerve endings under the skin or mucous membranes to cause an infection.
However, other diseases like bovine spongiform encephalopathy (mad cow disease) can be transmitted by consuming infected animal products. But this is not the case for rabies, since the virus gets destroyed during digestion in the stomach.
Can rabies be absorbed through the skin?
No, rabies cannot be transmitted through intact skin. The virus must reach mucous membranes or enter through open wounds in order to cause infection.
Casual contact like petting or handling an infected animal does not transmit rabies. Bites, scratches, and other wounds are required for the virus to enter the body and reach the nerves.
Applying infected saliva or tissue directly onto unbroken skin also cannot transmit rabies. The outermost layer of skin acts as an effective barrier that prevents absorption of the virus.
However, rabies can be transmitted if infected saliva directly contacts open wounds or mucous membranes around the eyes, mouth, or nose which gives the virus access to nerve endings.
Can you get rabies from infected animal blood or urine?
No, contact with blood, urine, or feces from a rabid animal does not transmit rabies. The virus is primarily shed in the saliva of infected animals.
Only the live virus introduced through infected saliva (primarily from bites) or directly into mucous membranes can cause rabies. The tissues, blood, and body fluids of a rabid animal do not pose a risk unless there is a bite wound or direct contact with mucosa.
Dried saliva around an infected animal’s mouth may contain rabies virus, but the other body fluids like blood and urine do not. Casual contact does not transmit the disease. Prompt washing of any potential exposure can also help reduce the already low risk even further.
Can you get rabies from vaccination?
No, it is not possible to get rabies from vaccines for humans or animals. Here is some information on the safety of rabies vaccines:
- Modern vaccines use inactivated or weakened forms of rabies virus that cannot cause disease.
- The vaccines stimulate immunity to rabies but do not contain live virus particles.
- No cases of rabies have ever been reported from a properly-administered rabies vaccine.
- Pre-exposure rabies vaccines are recommended for people at high risk like veterinarians and animal handlers.
- Post-exposure vaccines are also safe and highly effective at preventing rabies after a bite from an infected animal.
Rabies vaccines approved for use are safe and non-infectious. They provide protection from rabies by stimulating the body’s immune response to the rabies virus without containing any live virus capable of transmitting disease. Multiple doses are needed to provide complete immunity, either before or after exposure to the virus.
Can human-to-human transmission occur?
Human-to-human transmission of rabies is theoretically possible but has never been definitively documented.
Based on our understanding of how the virus spreads through saliva and nerve contacts, rabies could potentially spread between humans through:
- Bite wounds
- Contact between infected human tissue or saliva with open wounds or mucous membranes
- Organ or tissue transplants from infected donors
However, there are no confirmed cases of rabies spreading between family members, healthcare workers, or other close contacts of infected humans. Any potential theoretical risk would be extremely low.
Spread between humans likely does not occur because:
- Infected humans usually have viral shedding suppressed by the time symptoms appear
- Secretions are not as highly infectious as animal saliva
- Casual contacts do not involve exchange of tissue or fluids
Human-to-human transmission has not been observed in practice, even with close contact or donations from infected people. Bites from infected animals remain the almost exclusive route of rabies transmission.
Conclusion
While extremely rare, it is possible for rabies transmission to occur without a recognized bite or scratch wound. Non-bite exposures happen when infected saliva or tissues make direct contact with mucous membranes like the eyes, nose, or mouth. However, this type of transmission accounts for less than 1% of rabies cases.
Bites and scratches from rabid mammals remain the main route of infection in nearly all cases. For the general public, pet owners, and even animal handlers, the risk of contracting rabies without a bite, scratch or direct tissue contact is extremely low. Prompt washing if saliva contacts any open wounds or mucosa can help reduce an already negligible risk even further.