This article is more than 5 years old. Information may no longer be current.
Polio remains significant among worldwide infectious disease threats
Click Here to Manage Email Alerts
VANCOUVER — A recent outbreak in Tajikistan has highlighted the fact that challenges remain for the polio eradication effort, in addition to other initiatives, according to findings presented at the 48th Annual Meeting of the Infectious Diseases Society of America.
Scott Dowell, MD, MPH, of the Division of Global Disease Detection and Emergency Response at the Centers for Disease Control and Prevention, discussed current outbreaks of established and enigmatic infections worldwide. He said that the CDC maintains an ongoing list of the five biggest threats globally, which currently include polio; avian influenza (H5N1); chikungunya virus; cholera;and what are called ‘unanticipated threats’ by CDC officials.
“Of course polio is present in south Asia and central and west Africa, but the big news in polio is the outbreak from Tajikistan to other countries from the former Soviet Union,” he said in a presentation. Dowell noted that both the number of cases and number of countries in which polio can be found are decreasing, but that the battle is far from over.
“The picture seems optimistic to me, but perhaps it would not be for polio specialists,” he said. “The Tajikistan outbreak is definitely a concern.”
Two recent cases of avian influenza (H5N1) in Indonesia and ongoing cases in Vietnam and Egypt highlight the fact that the infection is not going away, according to Dowell. “H5N1 has made its way out of the media, but it is still among the deadliest threats in the world, given the approximately 60% mortality rate,” he said.
Dowell noted that reassortment of H5N1 with seasonal influenza or influenza A (H1N1) may also lead to infections that provide challenges for clinicians.
Outbreaks of chikungunya virus in France and China have caught the attention of CDC as well, according to Dowell. “Chikungunya has not traditionally been associated with those countries,” he said.
Dowell noted that although chikungunya virus has not been identified yet in North America, Aedes albopticus mosquitoes are becoming much more prevalent, particularly in the south. “We do not have the disease, but we have the vector,” he said. “It may only be a matter of time before these mosquitoes begin transmitting the virus.”
Regarding unexpected threats, a cholera outbreak was confirmed in Haiti at 11:00 pm on Oct. 22, according to Dowell. “This is the first time cholera has been seen in Haiti in the last 50 years, and we are definitely keeping an eye on it,” he said.
Dowell stressed that cholera remains a pandemic, particularly given that it is a significant problem in central Africa. “This is the seventh cholera epidemic in history, and it is an epidemic that is not to be trifled with.”
Reagrding enigmatic outbreaks, Dowell also highlighted an unexplained Japanese encephalitis outbreak in India; an undiagnosed liver disease in Ethiopia; several unexplained cases of lead poisoning in Nigeria; and the unexplained incidence of Nodding Disease in Africa. “We are still studying the pathogenesis of this complex seizure disorder,” he said.
For more information:
- Dowell #147. Presented at: the IDSA 48th Annual Meeting; Oct. 21-24, 2010; Vancouver, B.C.