Global Doc: Chikungunya

Author: Dr. Vincent DeGennaro Jr. ’02

Vincent DeGennaro

A previously unseen virus is tearing through the Western Hemisphere. A global traveler over the last decade, it has made its way from sub-Saharan Africa into Asia and now into the Caribbean, exploding into 18 new countries in a matter of months, discovering a multitude of new hosts in this region of the world.

“Be aware. The chikungunya is here,” the text from my colleague said, received as I boarded the flight from Miami to Haiti in the second week of May. Panic-monger, I thought to myself, remembering the list of diseases —West Nile, dengue fever, monkeypox — that hadn’t lived up to the hype, but SARS, MERS and swine flu did. Which type of epidemic would this be?

Even the name conjures up the heart of darkness, a violent beast charging out of the jungles of Africa. The name “chikungunya” is derived from a description in the Makonde language, used in what is modern day Tanzania, meaning “that which bends up,” a moniker conferred for the contorted pose of those afflicted with the severe joint pains associated with the disease.

One colleague already had a rash, joint pains and fever when I landed in Port-au-Prince. Within the week, another colleague who shares the office with me fell ill with headache and chills, unable to walk because his left knee was so swollen. My mind raced through all the illness he could have, from a gonorrheal infection of the knee to bacterial meningitis of the brain. New to this virus, I slowly came to recognize the classic signs of the disease — high fever, severe joint pains in the wrists and ankles, headache, and, finally, a diffuse, blotchy rash. Then my roommate woke up with a fever and ankles so swollen he had to shuffle instead of walk.

The virus is spreading at an alarming rate, far outpacing cases of malaria and dengue fever combined, though repeat infections are rare since most people develop immunity to the virus. It’s striking expatriates and Haitians at roughly the same rate, spreading more like a cold than a mosquito-borne illness, raging through entire offices in one week. People return to work after three or four days of illness when they start to feel better, but they are often still infectious and thus perpetuate the spread.

The species of mosquito, Aedes aegypti, that most often spreads the disease is found more often in cities than in swamps or jungles as they gravitate toward puddles of clean standing water. It spreads the virus during the day and is most effective in high density areas where people are congregated in public spaces such as offices and schools. Like the flu, the virus avails itself of the social nature of human beings. The mosquito also takes its meals bit by bit, instead of all at once like the nighttime mosquitoes. It may take one bite from an infected host and the next bite from an uninfected host, spreading the virus rapidly among those who spend their days together in a confined space.

The difference between chikungunya and malaria or dengue fever is that the latter two are endemic — permanent residents of the island of Hispaniola. With a long history of co-existence, populations develop some social immunity and cases only occur sporadically. No immune system in Haiti has ever seen chikungunya, leaving a population ripe for the picking.

First recognized in Tanzania in 1952, chikungunya remained confined to East Africa for decades before slowly spreading to Southeast Asia and India. In 2007, the first confirmed outbreak occurred in Europe, when more than 200 people in Ravenna, Italy, became infected. In December 2013, St. Martin reported the disease, the first in the Western Hemisphere. From January to May, the countries reporting cases blossomed from four to 14 to finally 18, including Haiti and the Dominican Republic.

Last week in Port-au-Prince, nurses called in sick in droves — first, the pediatrics nurses, then the nurses on the adult wards. Three of the five of the hospital’s drivers came down with the illness in a span of three days, likely due to the shared office.

The city and the hospital emptied out, eerily quiet, like a post-apocalyptic vision of the future. With half the city infected, there has been no traffic on the roads since nobody is going to school or work. Our hospital, principally dealing with trauma and critical care, has been half empty. With nobody on the roads, there are fewer car and motorcycle accidents, fewer gunshots and construction site mishaps. Last Saturday night, when we had to close the front gate to new admissions because of a shortage of nurses, it didn’t matter because the hospital was half empty and no new trauma cases came knocking.

The poverty and lack of infrastructure in Haiti exacerbate the biologic effects of the virus. Millions of people sleep in fully enclosed structures, and few have screens on the windows. Ubiquitous standing water provides breeding grounds for mosquitoes, and there has been no previous plan to spray for vector control. The under-resourced public health system can’t handle the influx of patients, and a population with low health literacy has been forced to confront yet another unknown and frightening disease.

The virus has an economic impact on the micro and macro levels as well — disease and poverty once again reinforce each other. The price of paracetamol (Tylenol), the mainstay of treatment, tripled, and the less scrupulous pharmaceutical street vendors substituted it with counterfeits. The epidemic also minimized the foot traffic and street commerce that drives the engine of the Haitian economy. Joint pains that linger for weeks will no doubt continue to slow manual laborers down in the future.

Like most illness, those at the extremes of age and those with underlying medical illnesses have fared worse than most. One patient’s family members couldn’t donate blood to her because they had fevers. Another had to cancel a surgery for breast cancer due to the illness. They also tend to present to the hospital with odd manifestations of the virus: one-sided leg swelling or swelling along scars, anemias, and unexplained joint pains without fever or only a fever without pains or a rash.

The United States has seen a dozen confirmed cases in the past few months, all of them contracted outside of the country’s borders. The clock is ticking on the arrival of chikungunya to the shores of Key West or Miami, carried by a traveler in the incubation phase. While not fatal, the pain associated with the illness and the lost productivity of those fighting through the severe joint pains will have a measurable impact on the south Florida economy, unlike West Nile. If chikungunya comes ashore during the rainy season of the summer, the spread could be even more rapid. While it likely won’t be as severe as the epidemic raging in Haiti, the bizarre name and subsequent painful illness may throw the community into a panic.

Be aware. Chikungunya is coming.

Vincent DeGennaro is an internal medicine doctor and a global public health specialist at the University of Florida’s Division of Infectious Diseases and Global Medicine and works half time in Haiti with the nonprofit Project Medishare. See his An American Doctor in Haiti blogs.