By: Dr. Hilary Slaven
World Rabies Day: September 28.
Since 2007, the Global Alliance for Rabies Control (GARC) has been promoting the annual World Rabies Day, in the hopes of raising awareness of the highly fatal virus.
Rabies: The Disease
Rabies is a zoonotic disease, meaning that it is passed from infected animals to people. It is considered to be a 100% preventable disease, with a highly effective vaccine that has been available for animals for over a century.
Unfortunately, according to the World Health Organization, the statistics show that over 55,000 people worldwide die every year (one person every 10 minutes) from virus exposure and subsequent illness. Most of these deaths are centered in underdeveloped nations in Asia and Africa (>95%). While a treatable disease, the treatment is expensive and futile once clinical signs develop. This means that once a person starts to show signs of illness, treatment is almost always ineffective and the patient is likely to die.
In the U.S., rabies is primarily found in the wild in bats, raccoons, foxes, skunks, and coyotes. These animals act as reservoirs for the disease, meaning that they can pass it along to pets (dogs, cats, and ferrets) or infect humans directly. Bats are the source of most human deaths in the Americas. In Asia and Africa, all human deaths can be traced to deep wounds or bites by rabid dogs.
The Infectious Path of the Rabies Virus
- Raccoon is bitten by a rabid animal.
- Rabies virus enters the raccoon through infected saliva.
- Rabies virus spreads through the nerves to the spinal cord and brain.
- The virus incubates in raccoon’s body for apporximately 3-12 weeks. The raccoon has no signs of illness during this time.
- When it reaches the brain, the virus multiplies rapidly, passes to the salivary glands, and the raccoon begins to show signs of the disease. The virus can be transmitted to other mammals days before the raccoon shows signs of disease.
- The infected animal usually dies within 7 days of becoming sick.
People who are infected by rabid animals can be treated with a series of injections (called post-exposure prophylaxis, or PEP). When given before a person develops signs of rabies, the efficacy rate is high for PEP injections. Symptoms of rabies infection include fever and pain at the wound site. It can take 1-3 months for these signs to develop. Over 40,000 PEP injections are given every year in the U.S.
|Table: Categories of contact and recommended post-exposure prophylaxis (PEP) (cdc.org)|
|Categories of contact with suspect rabid animal||Post-exposure prophylaxis measures|
|Category I – touching or feeding animals, licks on intact skin||None|
|Category II – nibbling of uncovered skin, minor scratches or abrasions without bleeding||Immediate vaccination and local treatment of the wound|
|Category III – single or multiple transdermal bites or scratches, licks on broken skin; contamination of mucous membrane with saliva from licks, contacts with bats.||Immediate vaccination and administration of rabies immunoglobulin; local treatment of the wound|
“All category II and III exposures assessed as carrying a risk of developing rabies require PEP. This risk is increased if:
- the biting mammal is a known rabies reservoir or vector species;
- the animal looks sick or has an abnormal behaviour;
- a wound or mucous membrane was contaminated by the animal’s saliva;
- the bite was unprovoked; and
- the animal has not been vaccinated.
In developing countries, the vaccination status of the suspected animal alone should not be considered when deciding whether to initiate prophylaxis or not.” (cdc.org)
Rabies in the U.S.
In the U.S., we have fought this virus for decades, with all states requiring dogs as pets to be vaccinated for the disease. Hawaii carries a ‘rabies-free’ status. While it is now a rare cause of death, prevention and monitoring of the disease is necessary to prevent future problems. For most of us, this means:
- Vaccinate dogs, cats and ferrets for rabies with boosters given appropriately according to your veterinarian.
- Keep pets supervised.
- Report stray animals to animal control.
- Report dog bites to your local veterinarian and seek treatment from your physician. Dogs should be quarantined for 10 days following a bite.
- Neuter and spay in tact pets.
Some people are good candidates for preventive rabies vaccination (those who work with pets and/or travel to rabies-endemic areas).
The estimated cost for this maintenance nationwide is $300 million a year.
Rabies continues to be a serious public health issue in underprivileged parts of the world, and statistics are showing that it may be on the rise.
It is a challenge to prevent rabies in these parts of the world for many reasons. These areas are remote, therefore difficult to get an assessment on number of deaths and get programs started to address the issue. The populations here are poor (often earning just a few dollars a year, literally) and cannot afford dog vaccinations or rabies PEP.
The way to address the problem, both medically and financially, is through vaccination programs. While a single canine rabies vaccine costs just a few dollars, post-exposure vaccinations can cost over $10,000 per person. With more than 15 million people worldwide receiving PEP vaccinations every year, this is a costly venture. According to the GARC, “A study published last year found that rabies currently costs the world’s poor $124 billion but could be prevented for just $6 billion.”
WHO supports targets for elimination of human and dog rabies in all Latin American countries by 2015 and of human rabies transmitted by dogs in South-East Asia by 2020. In this latter region a five-year plan (2012–2016) aims to halve the currently estimated number of human rabies deaths in endemic countries. (www.who.int)
What this means for us:
Maintain our vigilance with rabies protocols here in the U.S. to help prevent any future endemic with this disease in our country. Be responsible with pets and help to remove stray animals from the streets. Prevent overpopulation of pets with spay/neuters.
Be informed. Check out the CDC website for information on how you can help: http://www.cdc.gov/rabies/resources/get-involved.html