(COMMENTS FROM HEALTH OFFICER DR. RICK JOHNSON)
As the world is gripped by “Ebola fever”, what should our reaction be in the Eastern Sierra?
My personal view:
– We all should remain aware – stay tuned for updates from public health and local media.
– We all should be grateful for living where we do – first in a rural area, and then in the USA.
– We should know our sophisticated healthcare system is prepared to handle any influx of cases.
– Optional travel to the affected area should be absolutely avoided.
– The epidemic is similar to our wildfires – it will go on for weeks, but it will eventually burn itself out, because it kills so quickly.
– It will spread to other countries, due to better roads and the mobility of air travel.
– It is likely that cases will show up in the USA, most likely in places that have large populations from West Africa, such as Minneapolis, Washington, D.C., and Columbus, Ohio.
– Catching the virus requires close intimate contact with someone who currently has the infection. It is not spread through the air, food, or water.
In summary, there will be lots of headlines and fear about this epidemic in the days to come. I do not believe we will be impacted in the Eastern Sierra. However, we will stay informed and prepared.
Let’s count our blessings!
(Continue reading the following pages for more details if you find this fascinating like I do!)
Previous Ebola outbreaks have seen fatality rates as high as 90%. The current epidemic, primarily across Gambia, Sierra Leone, and Liberia, has seen 887 deaths out of more than 1603 confirmed infections, which equals about a 55% mortality rate to date. These numbers are immediately outdated, and grossly underestimated.
Ebola virus is a member of the Filoviridae family. First isolated in 1976, 5 subtypes of Ebola virus are now recognized, of which 4 are pathogenic to humans. The Reston subtype infects only primates. The most deadly form is the Zaire subtype, with the natural reservoir for the virus believed to be the fruit bat. The virus has also been found in porcupines, primates, and wild antelope.
Ebola virus incubates in infected humans for 2-21 days, with the majority of patients becoming symptomatic after 8-9 days. Once infected, patients can experience severe symptoms within 1-2 days.
Symptoms of Ebola include:
- Sudden fever, often as high as 103º-105º F;
- Intense weakness, sore throat, and headache; and
- Profuse vomiting and diarrhea (occurs 1-2 days after the aforementioned symptoms).
More severe symptoms, such as the development of clotting problems, can develop in as soon as 24-48 hours, leading to bleeding from the nasal or oral cavities, along with hemorrhagic skin blisters. The development of renal failure, leading to multisystem organ failure along with disseminated intravascular coagulation (DIC), can then rapidly ensue over 3-5 days, along with significant volume loss.
Patients who develop a fulminant course often die within 8-9 days. Those who survive beyond 2 weeks have a better prognosis for survival.
One of the difficulties encountered in identifying Ebola virus is that in the early days of the disease, the symptoms may be similar to those of other types of infectious diseases, such as malaria, Lassa fever, typhoid, cholera, and even meningitis. Only after 3-5 days (or even later in the course of the disease) might the hemorrhagic blisters — along with internal hemorrhage, the hallmark of the illness — become evident.
Although Ebola is a highly contagious virus, it is not airborne and not spread by droplets, such as how measles and influenza are transmitted. You cannot acquire Ebola virus if another person coughs or sneezes close to you, and it is not spread by casual contact. Rather, it is acquired by direct contact with infected secretions such as vomit, diarrhea, and blood primarily. It may also be spread by direct contact with saliva, sweat, and tears. Other means of transmission include contact of secretions with a skin opening or healing wound, or if a person contacts secretions and touches his or her eyes, nose, or mouth.
It is important to remember that only patients who are symptomatic are contagious and can then transmit the virus to others through their secretions. Those who have contracted the disease are primarily healthcare workers caring for patients, as well as family members who have had close contact with infected patients. Another method of infection has involved family members who handle corpses at the time of burial, along with those who eat fruit bats, antelope, or other animals potentially infected with the virus.
Studies indicate that the virus is in much higher concentration in vomit, blood, and diarrhea compared with saliva, sweat, and tears, making disinfection of public areas such as restrooms imperative in order to contain the virus.
The actual risk to citizens living and working in the United States is quite low, and the public should be well aware that emergency departments (EDs) and critical care units in the United States are well equipped and prepared in the event that a patient with a recent travel history from West Africa, along with flu-like and gastrointestinal symptoms, presents to the hospital.
As the ED is often the proverbial “front door” to the hospital, universal precautions, along with a protocol to quarantine and isolate such patients, is now a top priority for all EDs. Such a plan requires healthcare providers to wear personal protective equipment, including eyewear or goggles, facemask, gloves, and a gown.
Effective decontamination methods for the virus include steam sterilization, chemical sterilization, incineration, and gaseous methods.
What about the effectiveness of airport screening? During the SARS outbreak in 2003, the WHO recommended screening passengers with questionnaires and thermal scanners, but few sick
travelers were detected. Hong Kong screened 36 million passengers and detected 2 cases, and Australia screened 1.8 million people arriving, and 4 cases were detected by border screening, according to a 2005 study. Canada screened 4 million passengers and detected no cases, and Singapore screened 400 000 people entering the country and detected no cases.
The challenge for travel screening is that there is an ‘incubation’ period between someone being infected until they start showing symptoms. If infected people travel during that time, they are hard to spot based on symptoms. For diseases like influenza and SARS and Ebola, we have the additional problem that early symptoms can be difficult to distinguish from many other conditions, including malaria, which is widespread in all these countries.
In the past decade, five people have entered the US known to have a viral hemorrhagic fever like Ebola. It is reassuring that no one else contracted the disease.
At US airports, trained Customs and Border Patrol agents are working closely with the CDC to watch for sick passengers. Having just flown from London to LA last week, including standing in line with thousands of others for prolonged periods of time, I can appreciate both the difficult task, and understand the possibility of someone slipping through the system.