NSPO8043 Pandemics Infectious Diseases And National Security

A pandemic is the spread of a new disease within the world’s population (WHO 2010). In contrast, an epidemic is the sudden occurrence of a disease above the expected normal levels of the people living in a specific area. An example of an epidemic is Ebola which commonly occurs in the Democratic Republic of Congo (CDC 2010). With the 1889 and 1918 influenza pandemics, the word pandemic began to be associated with large-scale occurrences of diseases characterized by; a wide geographic coverage of the outbreak, high rates of attack by a new disease, low population immunity, severity, infectiousness and contagiousness (Morens, Folkers & Fauci 2009). The purpose of this assignment will be to look at the causes of pandemics by analyzing various diseases and the best solutions to overcome these pandemics.

Most of the world’s pandemics have originated from cross-species transmission between animal pathogens and human beings. The pathogen evolves into one that infects humans and maintains a long-term human-to-human infection without having the host reintroduce it (Johnson et al. 2015). This process is further broken down into five stages. The first stage involves animal pathogens that don’t exist in human beings under natural circumstances but once they evolve, humans contract them. However, the pathogen cannot maintain human-to-human transmission which is when it moves to stage 2. Examples include the West Nile Virus, rabies and the tularemia bacilli (Pike et al. 2010).

The change from stage 2 to 3 occurs when there is a sustained transmission of the disease between human beings with the pathogens in stage 3 going undergoing cycles of secondary transmission in humans. Diseases in phase three include Ebola and Marburg (Pike et al. 2010). In stage 4, diseases have gone through very many cycles of secondary transmission between humans without having the disease reintroduced. Examples include Influenza A and the dengue virus. Stage 5 covers diseases that were originally introduced by animal hosts but have now become exclusive to human beings and these are Human Immunodeficiency Virus (HIV), tuberculosis and smallpox (Pike et al. 2018).

The influenza A viruses are constantly changing and there is always a new virus circulating that is different from current or previous strains. In 2009, a new influenza A virus known as the H1NI virus was first detected in the US, spreading very quickly throughout the country and then to the rest of the world (CDC 2018). This new virus contained a new and unique combination of the influenza genes which had not been identified in either animals or human beings. Very few people had an immunity to this disease and the seasonal flu vaccines offered very little protection against the virus. The CDC estimated that between April 2009 and April 2010, there were 60.8 million cases of the H1NI virus with 151,700 and 575,400 succumbing to the virus (CDC 2018).

HIV/AIDS is a disease that is a global pandemic worldwide. Three decades ago, an outbreak of a new opportunistic infection was discovered in a small group of homosexual men in both California and New York. It was later referred to as the acquired immunodeficiency syndrome (AIDS) because it caused a complete loss of the CD4 T-lymphocytes which are important in cell immunity (Piot & Quinn 2013). A year after it was discovered, needle drug users, hemophiliacs and blood transfusion patients were diagnosed with the disease. The disease then became an epidemic in Central Africa soon after that. Two years after the AIDS virus emerged, a retrovirus later referred to as HIV was identified to cause AIDS (Piot & Quinn 2013)

With HIV information, tests were developed to identify infected people and prevention measures were introduced to reduce the spread of the disease. However, this was an exercise in futility because 10 million people were infected within the first decade it was discovered. The second decade saw a rapid spread of the disease around the world with Asia, the Soviet Union and the southern parts of Africa experiencing an explosion of the pandemic (Sharp & Hahn 2011). The introduction of antiretroviral drugs led to a significant decline of transmissions especially in high-income countries but in the low to middle-income countries, mortality rates rose to 2.4 million while new infections increase to 3 million (Piot & Quinn 2013).

Pandemics can also be caused by harmful germs or bacteria found in contaminated sources of food or water. The cholera bacteria commonly found in contaminated water infects a person’s intestines causing severe diarrhea and vomiting which if left untreated can cause death (Stille 2011). Cholera affects one to four million people in developing countries such as Africa, South America, Asia and it kills an estimated 142,000 people every year. This disease is common in places that lack proper sanitary facilities and where natural disasters have destroyed sanitation systems (Lewnard et al. 2016). Cholera is caused by a bacterium known as the Vibrio Cholerae which is usually killed by stomach acid in normal circumstances (Pratt 2011, p.40). However, if large quantities of the bacteria are ingested, they survive and enter the small intestine where they multiply. Human-to-human transmission occurs by touching the victim’s feces or food/water with their fecal matter (Pratt 2011, p.41).

Bacteria can also be transferred from one person to another leading to outbreaks such as the tuberculosis pandemic.  TB spreads by coming into contact with contagious moisture droplets generated from coughing or sneezing. Before antibiotics were developed, Tuberculosis was one of the main killer pandemics in the world because there was no cure for it (Stille 2011). After antibiotics were developed in the 1950s, the disease was kept under control but for a short time because the bacteria became resistant to antibiotics. Because the medication was ineffective, cases of drug-resistant TB grew especially in people with weak immunities (Stille 2011, p.9). It especially spread in people who had been diagnosed with HIV/AIDS. WHO estimated that 1.7 million people a year were dying because of tuberculosis with the majority of these casualties being in Africa and Asia (Stille 2011, p.10).

The US Agency for International Development came up with the Emerging Pandemic Threats program to rapidly identify and predict the emergence of pandemics and increase threat levels in countries so that they can deal with them effectively. This approach draws from efforts to deal with the H5N1 virus and from the fact that human beings, animals and the environment are intertwined (Morse et al. 2012). The approach makes use of predictive modelling, PREDICT, to identify areas where animal hosts and human beings are likely to propagate the emergence of a new disease. It is therefore effective in managing disease outbreaks caused by animal to human transmission (Morse et al. 2012).

Experts such as epidemiologists, ecologists, virologists and veterinary doctors are used to build an early warning system that detects and reports emerging diseases on a global level. They obtain timely and reliable data by surveilling unusual events in hotspot countries and analyzing whether animal pathogens have the capacity to emerge and spread diseases into human populations (Morse et al. 2012). PREDICT is currently being used in 20 countries to detect emerging disease hotspots by surveilling human-animal interactions where disease transmission is highly likely. Within the first two years of the program, samples from 20,000 animals collected in 20 countries produced 150 new viruses from animals that harbored disease pathogens. This shows the approach is effective because the samples will be used to refine hotspot mapping globally and develop strategies to prevent pandemics. The ultimate goal of PREDICT will be to prevent pandemics in the future at the animal source before they affect humans (Morse et al. 2012).

Oral cholera vaccines have been used to effectively manage cholera outbreaks globally. These vaccines are given in two doses that are 14 days apart and they provide protection that can last for five years. A 2015 study conducted by Azman et al. (2016), looked at the effectiveness of using a single dose cholera vaccine in managing an outbreak of cholera in Juba, Sudan. They found that the one dose vaccine had a similar effect to the two-dose vaccine which meant that treatment costs would go down considerably and more people would get access to the vaccine. The current global shortage of the oral vaccine and the difficulty of administering two doses to a larger population also made the one dose oral vaccine a better option (Azman et al. 2016).

Because the country was facing a cholera outbreak with limited vaccines, the local public health office together with Medecins Sans Frontieres decided to use the single dose oral vaccine. The study found that this vaccine had an 87.3% effectiveness in reducing cholera for a period of up to 2 months. These results showed that the one dose oral vaccine was effective in preventing a cholera outbreak in Juba and that this new strategy was going to be useful in managing outbreaks in areas where vaccines were limited and rapid protection was required (Azman et al. 2016).

This report has dealt with pandemics, the causes of pandemics and the solutions that can be used to prevent pandemics now and in the future. If not managed properly, pandemics can cause huge mortalities and lead to high healthcare costs. While they have become more manageable now, more preventive measures are needed to reduce the high number of mortalities that occur when a pandemic breaks out.

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