September 28 is World Rabies Day, a global health observance that seeks to raise awareness about rabies and enhance prevention and control efforts. In the spirit of World Rabies Day, rabies program EIS Officer Ryan Wallace describes his travels around the world and how his work supports global rabies prevention and control efforts. This is the first of a two-part series.
PART 1 OF 2
Rabies is everywhere, and it’s literally on the move.
In the United States, rabies is found in raccoons, skunks, two species of foxes, and 16 different varieties of bats. All of these hosts make for a cozy biological home to many different strains of the rabies virus. Overall, 6,163 animals captured last year tested positive for rabies, but this is only a small fraction of the true burden of rabies in our wildlife.
Yet few people die of rabies in the United States.
Those are some of the pertinent numbers in my role as an EIS officer in the rabies program at the Centers for Disease Control and Prevention (CDC). Here are two more: 25 percent and 50 percent.
The first was presented with confident assurance when I was considering whether to join the rabies program. I loved the idea—the challenge of chasing and understanding a dangerous and exotic disease.
“What would you do if we got a call from Namibia saying they needed emergency assistance? Could you leave tomorrow?” I was asked during my interview. “Absolutely,” I said.
But as a husband and father with two young kids, I followed with a question of my own: How much travel can I expect?
Twenty-five percent, I was told.
That’s where the second number comes in. This year alone, I have already spent 2 months in Africa, 1 month in Haiti, 1 month travelling between state health departments in the United States, and 2 weeks in Taiwan. All of that, with 3 months left in the year. For the mathematically challenged, that’s 50 percent—so far.
But as is the case with so much of what CDC does, protecting people from rabies in the United States means detecting it—and investigating it—in other countries as well. And that’s why I’m so often on the move.
Because of strong and effective rabies prevention policies, many of the cases of human rabies found in the United States today are in people who acquired the disease abroad, rather than here.
And this is where my 3 months of nonstop world travel begins.
In early May, a young man from Central America bid his wife, child, mother, and friends goodbye and set out on a long journey to the Mexico-United States border. He was heading to Boston, where he had family and was hoping to find work.
He was detained crossing the border and during his 2 weeks in federal detention, he began to experience arm pain, nausea, and lethargy. It quickly progressed to an inability to swallow, which caused him to spit repeatedly in detention housing. He became agitated and was transferred to a hospital, where he died.
It’s one case, but it raises an obvious question: With rabies around us, why don’t we see more Americans dying?
The different rabies strains in the United States are just as infectious as in countries that have a high burden of human rabies. However, our public health system—made of local, state, and federal rabies control professionals—has worked diligently over the past several decades to eliminate canine rabies (rabies viruses that circulate in dogs) and thus has greatly reduced human exposure. These professionals continue to ensure that animal exposures are reported to the correct authorities so that preventive vaccination can be provided, if necessary, to people potentially exposed. Overall, an estimated 40,000 people receive rabies post-exposure treatment each year in the United States. Thanks to this system, numerous lives are saved every year.
Working with its partners, CDC aims to help keep rabies in check. And that brings me back to the case of the man from Central America.
When his rabies diagnosis was confirmed by a CDC lab, our program was called to assist with the public health investigation. I was already travelling for a conference in California when the call came.
“Dr. Wallace, this is the CDC Emergency Operations Center. The rabies program wants you to be in Texas tomorrow morning. Can you leave tonight?” “Absolutely,” I said.
By now, I’m accustomed to schedule changes. I passed off a few presentations to my colleagues and was on my way to Texas later that night. After brief introductions with the local health department staff, we were off to the first of five detention facilities where the patient had been housed.
Human-to-human transmission of rabies is thought to be extremely rare. It requires that saliva or tears from an infected person make direct contact with mucous membranes or fresh wounds of another person. During human rabies investigations, we are typically concerned about medical personnel who have intimate contact with the patient. Close friends and family are often at risk, as well.
Although contracting rabies from another person is difficult, the consequences are severe if potential exposure is not evaluated and appropriate medical care is not provided promptly. It’s the reason investigations are routinely conducted. On top of the typical risks for friends and family, detainees are often housed in close quarters with shared utensils, cigarettes, or other items that may facilitate exposure. And as I mentioned earlier, this particular patient spit repeatedly while he was in detention housing.
Over the next 2 weeks, we investigated five facilities, reviewed thousands of detainment records and security videos, and coordinated with six countries to identify all those potentially exposed. Nearly 100 detainees were determined to be at risk for contact with the rabies patient. All 100 of them needed to be assessed to determine their risk for exposure to rabies. Many of these detainees had already been returned to their home countries, so we worked with the Pan-American Health Organization (PAHO) to notify ministries of health in their home countries and to assist with rabies risk assessments.
In the end, all high-risk persons were identified by their home countries and received rabies vaccination. Additional investigation found that the young man who died of rabies was bitten by a dog in his home village approximately 3 weeks before he became ill.
Job done, fly home, spend some quality time with the wife and kids.
But my work is not done. Over the weekend, I find that the bathroom tub is leaking, the pond pump broken, and the kitchen drain smelling like something died in it. No problem. I am a handyman too. I have renovated two houses, going on three.
But before any work is started, the phone rings. “Dr. Wallace, Taiwan is requesting immediate CDC assistance for the re-emergence of rabies for the first time in over 50 years. Can you fly out on Friday?”
Check back on Wednesday, September 23, for Part 2 of this blog series to learn about the elusive Formosan ferret badger and the EnKunga, the mythical goat-sized, man-eating Ugandan bat.