Can rabies be transmitted between humans? What are extremely rare cases?

Can Rabies Spread from Person to Person?

Overall, the answer is: Theoretically possible, but nearly impossible in reality.

Think of it as an event with an extremely low probability—many times less likely than winning the lottery. In daily life, there's absolutely no need to worry about contracting rabies from another person.

Rabies transmission requires very stringent conditions: infected bodily fluids (primarily saliva) or neural tissue must enter the bloodstream of another person through broken skin or mucous membranes.

We know that rabies is mainly transmitted through bites or scratches from infected animals (such as dogs, cats, bats, etc.).

Why is Human-to-Human Transmission So Rare?

There are several key reasons:

• Patient Condition: When a person develops active rabies symptoms, they are already in the terminal stage of the disease. They typically appear extremely weak, paralyzed, or comatose. These patients are admitted to intensive care units (ICUs), connected to various tubes, and completely incapable of aggressive behavior like biting. The movie-like "zombie" scenes of patients violently chasing and biting people do not occur in real-world human cases.
• Medical Precautions: Medical staff take strict isolation and protective measures when treating rabies patients (wearing gloves, masks, and gowns) to avoid direct contact with their saliva, blood, or other secretions.
• Viral Load: Research shows that the viral load in the saliva of infected humans is significantly lower than in infected animals, resulting in much weaker transmission capability.
• Atypical Symptoms: Human rabies primarily manifests as hydrophobia (fear of water), aerophobia (fear of drafts), throat spasms, and progressive paralysis, rather than aggressive behavior.

Therefore, you definitely cannot contract rabies through everyday contact with an infected person, such as talking, shaking hands, or even sharing the same room.

What Are Some Extremely Rare Cases?

Although transmission through normal means is nearly impossible, global medical history has documented a few exceedingly rare cases of "human-to-human" transmission. These occurred under very specific, extreme circumstances:

1. Organ and Tissue Transplantation (This is the primary route of "human-to-human" transmission)

This is currently the most well-documented and definitive form of human-to-human transmission.

• How does it happen? An organ donor died while infected with the rabies virus, but the infection was not diagnosed (because symptoms had not yet developed or were atypical). When their organs (most commonly corneas, followed by solid organs like kidneys or livers) are transplanted into recipients, the virus replicates in the recipients' bodies and eventually causes rabies.
• Notable Cases: Tragic incidents have occurred in the United States and Germany. A donor who died from an undiagnosed disease transmitted the virus through donated organs to multiple recipients, who consequently died of rabies. Such events have led to stricter global screening protocols for organ donors.

2. Transmission via Bites or Saliva Contact (Exceedingly rare, and evidence is inconclusive)

Globally, such cases are extremely rare (only a handful exist) and often lack definitive proof. They are typically classified as "highly probable" or "suspected."

• The Ethiopian Case: Medical literature reports a case where a mother, caring for her son with rabies without protective measures, experienced close contact likely involving her son's saliva. She may have had unnoticed minor wounds, resulting in transmission.
• Historical Records: Centuries of medical history might contain one or two more accounts of patients biting caregivers. However, the details and diagnoses of such cases cannot be confirmed by modern medical standards.

It must be emphasized that these cases are "single-digit" events across hundreds of years of global medical records. They represent extreme medical exceptions and hold no relevance to the daily lives of the general public.

Summary

• Rest Assured: Human-to-human transmission of rabies is nearly impossible in real life. You do not need to feel anxious about it.
• Source of Risk: The greatest risk of rabies always comes from animal bites or scratches.
• Crucial Action: If bitten or scratched by a cat, dog, or other animal, immediately wash the wound thoroughly with soap and water and get rabies vaccination and immunoglobulin as soon as possible. This is the most effective and critical way to prevent rabies.
• Transplant Safety: Organ transplantation now involves extremely rigorous donor screening processes, minimizing the risk of rabies infection via transplants to the lowest possible level.

We hope this explanation helps clarify that concerns about "human-to-human" transmission—a truly minuscule risk—are unnecessary.