Public Health Topic: Ebola Zaire (Gabon)

The percentage of Ebola deaths has increased from 57% to 74% among the people of Gabonese Republic from January 1996 to January 1997.

Magnitude

From January to April of the year 1996, there was an outbreak of Ebola Zaire in the Mayibout area of the Gabonese Republic. It was found that there were 19 original cases of Ebola-Zaire and all 19 people involved ate a dead chimpanzee they found in the forest. The disease managed to spread to some family members of the 19 people before control and prevention methods were in place. In the end, 37 people (17 females, 20 males) were reported to be infected with the disease. 21 (57%) of these people were reported dead. 

Later on, from July 1996 to January 1997, 60 new cases of humans infected with Ebola Zaire were reported in the Booue area of Gabon. Some patients were transported to a hospital in Libreville, Gabon, and cases started to pop up there as well. Soon after the first few cases, a dead chimpanzee was found in a forest near Booue that was confirmed to have Ebola. There were 44 reported cases of Ebola-Zaire in Booue with 33 deaths and 14 cases in Libreville with 10 deaths. Of these people, 45 (74%) of the people infected were reported dead.

The surveillance that is available can be used to determine what public health actions need to be taken in the case of another outbreak. Surveillance also determines where certain health resources are needed the most. Lastly, the surveillance available can be used to determine how effective control and prevention methods are in several places in Gabon. Using the surveillance above, I can see how the virus traveled from place to place (like from forest to town and from Booue to Libreville). I can also guess at how the humans became infected with the disease in the first place by associating the dead chimpanzees with the outbreaks.

Direct Indicator: (1) Lab tests used to confirm the existence of Ebola in the chimpanzees and the infected people. (2) 57% and then 74% of people in Mayibout and Booue respectively were confirmed dead from an Ebola infection.

Indirect Indicator: (3) A high number of people who are in close contact with each other showing the symptoms of a hemorrhagic fever.

One strength in the statistics I cited is that they are very direct and clear measures of this particular incidence of Ebola Zaire. A weakness is that the statistics available are only from passive surveillance. That could lead to inaccuracies in the actual statistics. 

References

Known Cases and Outbreaks of Ebola Hemorrhagic Fever, in Chronological Order | CDC Special Pathogens Branch. (n.d.). Centers for Disease Control and Prevention. Retrieved March 30, 2013, from http://www.cdc.gov/ncidod/dvrd/spb/mnpages/dispages/ebola/ebolatable.htm

Waterman, T. (n.d.). Ebola Zaire Outbreaks. Stanford University. Retrieved March 30, 2013, from http://www.stanford.edu/group/virus/filo/eboz.html

Public Health Topic

I still do not know what public health topic I would like to address yet but I am thinking about choosing between Malaria, Ebola, and West Nile Virus. 

Malaria

Malaria is a serious disease that can lead to death depending on how quickly it is diagnosed and treated. It is caused by infection with malaria parasites from the Anopheles Mosquito. There are two types of Malaria that are observed: uncomplicated malaria and severe malaria. Uncomplicated malaria (which is rare) lasts about 6 to 10 hours in which a person goes through the cold stage, the hot stage, and the sweating stage. Symptoms include fever, body aches, chills, and more. Uncomplicated malaria can sometimes be misdiagnosed as a common infection that has similar symptoms. Sever malaria, as the name suggests, is more serious that uncomplicated malaria. Malaria infections become active in the blood so severe malaria occurs when there are abnormalities in a person’s blood or metabolism. It can also occur when the infected person suffers from serious organ failures. The symptoms like low blood pressure, severe anemia, acute kidney failure make it imperative that anyone with sever malaria find treatment as quick as possible.

Problem Definition

There is a breakout of fever, chills and sweats followed by acute kidney failure in areas with a large population of mosquitoes.

Ebola Hemorrhagic Fever

Ebola is a serious disease that causes severe viral hemorrhagic fevers in humans and primates. Humans contract this disease through close contact with the bodily fluids of infected animal and other infected humans. Symptoms include fever, muscle pains and more that lead to diarrhea, internal and external bleeding, impaired liver and kidney functions, and more. The disease has a case fatality rate that varies between 25% and 90%. Ebola can sometimes be misdiagnosed as Malaria, typhoid fever, cholera, and other diseases with similar symptoms. A best way to diagnose Ebola is through testing. As of now, there are no specific treatments or vaccines for Ebola so infected people are usually given intensive supportive care.

Problem Definition

An increase in deaths caused by hemorrhagic fevers has been found in several zoo workers and the monkeys they look after.

West Nile Virus

West Nile Virus is an illness that is contracted from the bite of an infected mosquito which gets an infected bird. This illness can be very serious but usually is not. Serious symptoms include high fever, coma, vision loss and more. The CDC states that only 1 in 150 infected people actually get severe symptoms. More moderate symptoms can appear in about 20% of infected people. These include fever, headache, nausea, and more which can last for just a few days. However, most infected people, approximately 80%, show no symptoms at all of West Nile Virus. People with a mild form of the illness usually do not need medical help since the illness will go on its own but if an infected person shows serious symptoms, they should get medical help as quickly as possible.

Problem Definition

There has been an incidence of high fevers and comas in a small community with a large population of birds and mosquitoes.

All three of these diseases are important public health issues for different reasons; malaria because it is a frequent and sometimes deadly disease, Ebola because it is not so frequent but is very deadly, and West Nile Virus because for those who show signs of illness, it can be a very serious problem.I chose Malaria because I once had it when I was a child and since I became interested in public health, I've been fascinated with how it's treated in different communities. I chose Ebola because I once read about it in a book called Hot Zone and I was curious about how such a deadly disease is treated in the real world. Lastly, I chose West Nile virus for no special reason. I just thought I would get more data from it. At the moment, I'm leaning towards Ebola. 

Contagion

In the movie Contagion, a business woman contracts a disease (later named MEV-1) on her travel to Hong Kong and it is not visible until days after she's infected various people on her plane ride back home. This is the beginning of a MEV-1 pandemic that arouses a wave of fear in the people of Minneapolis. The movie also follows the decisions of various government officials and how they deal with the outbreak. Dr. Erin Mears, an Epidemic Intelligence officer, is sent to Minneapolis to investigate the disease when she dies from it, Dr. Leonora Orantes, an Epidemiologist, is sent to Hong Kong to investigate the beginning of the disease when she is kidnapped for the cure, and Dr. Ally Hextall, a CDC scientist, works on a vaccine for MEV-1 which she later discovers. At the end of movie, viewers are taken back to see each step that leads to the outbreak from how the bat and the pig created the virus to when the business woman shakes the hand of a butcher that was cutting up the pig.

The first time I watched this movie, I was in High School and I was just understanding that Health is not just what you see in the hospital. This movie is one of the reasons I got so interested in Public Health, epidemiology specifically. I was really impressed with how realistic the movie was and how well it described the responsibilities of many different Public Health officials from those who work in the government to those who work in the labs and even to those who work in the field. Now that I am taking this class, I am able to understand the importance of the CDC in the event of such a huge outbreak, The first time I watched the movie, I did not know so much about what Public Health officials did and I thought the government should be the one making final decisions on the health of the public. Now, I understand that the government has it's functions and Public Health officials have their functions. In other words, the government should take a step back when an outbreak occurs and let the CDC do their job.

An outbreak occurs when the incidence of a disease (number of new cases) at a specific place and time is greater than what is expected. For example, if one case of smallpox is found anywhere in the US, it would be considered an outbreak since smallpox is not an expected disease. However, if one case of the flu is found during flu season, it would not be considered an outbreak since it is expected that some people get the flu. In the movie, MEV-1 is a new disease so no illnesses were expected, thus it was an outbreak.

An outbreak investigation is, simply put, the investigation of an outbreak. There are 10 steps epidemiologists follow that the CDC says are involved in investigating an outbreak. They are to

1. Prepare for field work
2. Establish the existence of an outbreak
3. Verify the diagnosis
4. Define and Identify cases
5. Describe and orient the data in terms of time, place, and person
6. Develop hypotheses
7. Evaluate Hypotheses
8. Refine hypotheses and carry out additional studies
9. Implement control and prevention methods
10. Communicate findings

In some or most cases, these steps can be followed in a different order and repeated as much a necessary. The epidemiologists and scientist follow different steps of the outbreak investigation as their jobs require. Dr, Mears manages to follow all the steps stated and in the process contracts the disease. Dr. Orantes is in the process of following the steps of the investigation when she is kidnapped. Their jobs are obviously very dangerous is different ways.

Isolation and quarantine are some of the ways step 9 of an outbreak investigation can be carried out. If a person has a disease that is highly contagious, they are usually put in isolation so that other people surrounding them do not acquire the disease. Quarantine is when people who are suspected of having been exposed to a contagious disease are separated from others in case they start to show symptoms of the disease. The difference between isolation and quarantine is that Isolation deals with people who are already sick while quarantine deals with people who have been exposed to a disease. In the movie contagion, Mitch Emhoff is quarantined when his wife dies from MEV-1 and he is suspected of having it. Later on in the movie, the whole city of Minneapolis is quarantined from the rest of the country when the government realizes that too many people have been exposed to the disease. Many of the sick people in the movie are later isolated when the seriousness of the disease is comprehended.

In the movie, several public health agencies could have been better "prepared" for MEV-1. When Dr. Mears was sent to investigate MEV-1, she had to work with local government officials to create a space for the infected people to be treated. However, many the people she was working with were reluctant to help since they did not fully understand what they were dealing with and this slowed down the control and prevention of the disease. They all could have been better prepared if there was more effective risk communication between the different public health agencies and the public. Since they weren't better prepared, Dr. Mears had to take the time to explain to the government officials what could be prevented with their resources when they should have already been informed of the dangers of the disease.