Infectious Disease Update: Ebola, Enterovirus and Chikungunya
There we were, minding our own business and enjoying our relative health. Diseases like West Nile Virus and Lyme Disease were long out of the spotlight. But now, it seems, the news is again saturated with new players in the man vs. microbe struggle. Stories on Ebola, Enterovirus D-68 and Chikungunya are creating alarm and posing threats on different levels.
Is this just sensationalism on the part of the media or do we have reason for legitimate concern?
"A burial team from the Liberian Ministry of Health unloads bodies of Ebola." Source: CNN
Ebola outbreaks have come up from time to time in Western Africa since it was first discovered nearly 40 years ago. Typical of the outbreaks, the disease hit hard and then retreated. Ebola is thought to be carried by bats or other wild animals, transmitting from contact with blood, meat or infected fluids. Characteristically, humans are bad hosts from the standpoint of the virus because a large portion of those infected die very quickly, making person to person transmission less possible. Because of this the outbreaks thus far have eventually killed off over a relatively short time.
This outbreak, however, is the largest to date. Most recent figures estimate that 2,800 people have died so far. The virus has been determined to be 69-73% fatal and these numbers continue to grow rapidly. Recently, Sierra Leone imposed a mandatory three day shut-down where citizens were confined to homes as a measure to contain spread of the disease. Doctors without Borders have spoken against this measure and advocated for a rapid pouring in of resources to contain the epidemic. Treatments and vaccine research are still in fledgling stages and will not save the day in this outbreak.
Epidemiologists are looking at various models of growth and speculating on best and worst case scenarios. A worst case scenario recently published speculated that Western Africa could see 1.4 million cases by mid-January 2015. The authors were quick to reassure this as unlikely, however, because of the rapidly growing global efforts to contain the epidemic.
One concern has circulated that if the epidemic persists it may continue to smolder as an endemic, ever-present low level infection in humans. Until now, these epidemics have popped up from an animal-to-human spark, igniting human-to-human transmission. Endemic prevalence would be the most likely, albeit unlikely, scenario of far-reaching spread beyond the borders of Western Africa. For the epidemic to peak and reach very low levels around the beginning of 2015, experts report that a rapid and aggressive response needs to happen with containment efforts.
"Enterovirus D68 is spreading across the nation with potential cases in the state of Washington." Source: KULR8 News
The news on Enterovirus D-68 (EV D-68) is really a good news-bad news scenario. This virus, which was once quite rare, and causes wheezing and cough with or without a fever, has sure made itself known this month as it spreads like wildfire. Cases were first reported in the heartland of Kansas City when the CDC confirmed 30 cases in children with underlying lung conditions who were hospitalized with breathing difficulties. Some required treatment with mechanical ventilation. Within days, the virus was confirmed in six states and this week it was reported to have hit each coast.
Experts feel that it is likely that thousands have been infected with more minor symptoms. The rapidity of spread is for the most part the extent of the bad news. The good news lies mainly in the fact that there have presently been no fatalities from infection of this virus. In addition, although available resources for care have been tested, they have held against the huge surge of illness.
The illness has no cure and those ill must ultimately rely on the immune system to fight it off. Supportive care is helpful with asthma therapy, steroids and breathing support if needed. No vaccine exists for EV D-68.
"Health workers identifying chikungunya in a patient after the disease traveled to the south of France via a tourist." Source: Valentin Pezet, Jules Foulongne, and Nicolas Gueniot
Chikungunya (pronounced "chicken-goon-ya") is a virus transmitted by mosquitoes which causes a syndrome of fever, rash and joint pain. Rarely, the disease can affect the brain and lead to death. Though the fever and rash resolve in a few days, the joint pain can persist much longer. Before recent years, Chikungunya was endemic in India, Southeast Asia and parts of Africa. In 2013, the illness emerged in the Caribbean and spread rapidly to most all the islands and beyond to Central and South America. As cases have continued to grow, Chikungunya has now crossed into our borders, mainly in southern Florida. To date, 751 cases have been reported in Florida. Experts feel that Chikungunya will not gain a foothold in the U.S. as it has in more tropical, mosquito-infested southern locales.
Treatment of Chikungunya is supportive with anti-inflammatory medications such as ibuprofen for the fever and joint discomfort. Prevention is of primary importance in fighting this illness via taking precautions against accruing mosquito bites when in Chikungunya risk zones. Vaccines for Chikungunya are in the development phases. While they are showing promise, they are not immediately forthcoming.
It seems we are always on the defensive against microbial invasion. While there is reason for some caution against these recent threats, the medical forces seem to be winning out.
1. Ever-Present Endemic Ebola Now Major Concern for Disease Experts. Medscape. Sep 23, 2014.
2..Ebola Cases Could Rise to 1.4 Million in 4 Months, CDC Says. Medscape. Sep 23, 2014.
3. Estimating the Future Number of Cases in the Ebola Epidemic — Liberia and Sierra Leone 2014–2015, CDC Supplement, September 24, 2014.
4. Enterovirus-D68 Is Now Coast to Coast. Medscape. Sep 19, 2014.
5. Chikungunya Virus Concern Growing. Medscape. Sep 23, 2014.