BOONE — Mark Twain once said, “History doesn’t repeat itself, but it often rhymes.” To see where that sentiment holds true, look no further than today’s current state of affairs and a few pandemics of the past.
There have been approximately 10 pandemics in modern history, according to the World Bank. These include the fifth cholera pandemic, Spanish flu, Asian flu, Hong Kong flu, HIV/AIDS, SARS, Swine flu, MERS (classified as an epidemic), Ebola, Zika and now COVID-19.
While the effects of these outbreaks have had disastrous consequences on cultures and economies, the silver lining that has emerged out of the impact of these diseases has been the development and advancement of medical technologies that have saved the lives of vastly more people than those who had perished at the hand of these outbreaks and infections.
Michael Opata is an associate professor at Appalachian State University and studies immunology, infectious diseases and the treatment thereof. Opata completed his Ph.D. at the University of Kentucky College of Medicine where he studied pneumocystis pneumonia, or a fungal infection that is one of the leading killers of HIV patients. He also completed his post-doctoral research at the University of Texas Medical Branch where he researched infectious diseases and why scientists are unable to develop an effective vaccine against malaria.
“The key thing is to understand the behavior of the infectious agent that is causing the disease. That takes a while when it is a new infection such as the coronavirus,” Opata said. “Since it is a new strain, it means that no one or very few people have been exposed to it. At least right now, we understand that it is transmitted through droplets and the first thing to do is to be able to reduce the spread by implementing measures such as social distancing.”
Social distancing keeps the rate of infections from surpassing a point in which hospitals become overwhelmed and patients begin dying because the health system is no longer operating efficiently. The measures also give scientists time to develop treatments for the disease. However, that process is far from being simple.
“There are the two strategies to making vaccines. You can make a vaccine that is protective or a vaccine that is preventive,” Opata said.
The process is completed through three phases of clinical trials that can take a period of time to be administered and studied properly. First, the vaccine must be successfully administered to an animal, such as lab mice, in a controlled setting. Once the animal is shown to have built up an immune response, the first clinical trial begins and the vaccine is given to a group of about 20 to 100 people who have the infection once researchers know that the vaccine can work.
It can take up to six months to see the immune response before the second phase of clinical trials begins. It can then take more than a year for the second phase to be completed, as more than 500 people are given the vaccine. In the third phase the number of test subjects jumps into the thousands and the time it takes to study these people increases as well.
“In situations like the one we have right now, that time can be reduced. The catch is that you might think the vaccine will work, but see that the vaccine is induced by a mutated form of the [virus]. You have just inactivated it because you understood its behavior. It might mutate and start to cause a new disease again, but that is why we do these clinical trials to be able to make sure it is controlling what it is supposed to control rather than causing another disease,” Opata explained.
The first vaccine as we know it today was developed in 1796 and was used as a prevention against smallpox and cowpox. Smallpox is thought to have originated in India or Egypt more than 3,000 years ago and was the main contributor to the decimation of native peoples across the Americas after Europeans first set foot on the continents. In 1980, the World Health Organization declared the virus to be eliminated.
Lessons from past pandemics
COVID-19 belongs to a family of coronaviruses that is similar to severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). However, the similarity to these other viruses has not led scientists to similar treatments.
“[Scientists] would have some experience [with these other viruses], but the problem is that when they compare the current virus it’s different. It’s in the same families, but it is different in its behavior. That is why it is causing more infections and it has spread globally as opposed to SARS, which was contained much faster,” Opata noted.
SARS spread throughout four continents and 37 different counties, causing 744 deaths out 8,098 possible cases. The virus’s spread began in 2003, supposedly beginning in Zhongshan, China. It was isolated in laboratories in Hong Kong, Germany and Atlanta but not before causing billions of dollars in GDP losses in Hong Kong, China and Singapore. There is no cure for SARS, only supportive care. There has not been a reported case since 2004.
MERS was first identified in Saudi Arabia in 2012 and spread to 22 different countries, causing 659 deaths out of 1,879 symptomatic cases. There is also no specific antiviral treatment for MERS, and the majority of cases have spread across the Arabian Peninsula.
“The history from previous pandemics has shown that isolation and keeping people away from each other helps with the reduction of the number of people who are infected,” Opata added. “When you think about the Spanish flu, they showed at the end of the first World War when people congregated in Philadelphia, they saw that there was an increase in deaths after that week as opposed to cities like St. Louis, where there was a shutdown of sorts of people getting together.”
The Spanish flu was the deadliest pandemic of the 20th century, lasting between 1918 and 1920. Estimated deaths from the Spanish flu ranged between 20 million to 100 million.
“What we learned from the flu pandemics in the 1950s and 1960s, was that there was improvement in immunology and diplomacy. [Scientists] were able to understand the immune response to this infection. That is when most of the vaccines were developed, especially between the 1918 and the 1950s flu epidemics,” Opata said.
Scottish scientist Alexander Fleming discovered penicillin, the first antibiotic, in 1928 and it became widely used in the 1940s to treat common illnesses. The later establishment of health organizations provided further innovation in the fight against sweeping diseases.
“I think the major thing was record keeping and the establishment of the CDC and World Health Organization after the Spanish flu,” Opata explained. “When you look up the Spanish flu, you find that there was no definite number of people who died. They give a range between 20 to 50 million because there was no good record keeping by then. The ability to be able to define this, to keep medical records of outbreaks of infectious diseases, was one of the lessons that we learned from the previous pandemics.”
Another pandemic that has left the public’s conscience but is still ongoing is HIV/AIDS. The virus has resulted in the deaths of nearly 37 million people, and it was first identified in a blood sample in 1959 in the Democratic Republic of the Congo. There is still no cure or vaccine for the disease, but treatment persists. HIV/AIDS is particularly malicious as it attacks the immune system directly.
“Scientists are trying to look at using antiretroviral therapy, which inhibits the virus from entering the cell and binding to the surface of the cell so it cannot replicate. It uses your own cells to replicate itself,” Opata said. “If you inhibit the entry of the virus into the cell, that is one way of protecting [yourself]. That is how most of the HIV medications work. The reason why they’re still looking at the coronavirus is because they do not know the molecule it uses to be able to attach to the human cell. When they’re studying its behavior, they’re trying to study the molecule the virus itself uses to infect the human cell so that it can enter to cause the disease.”
The immune system and its importance
The immune system is the body’s first line of defense against any infection even if the infection is new, like COVID-19. Research has shown that the surest way to boost the body’s immune system is through exercise, eating a healthy diet that includes various fruits and the reduction of stress.
“The more stress you have, the more susceptible you are to infection because your immune system is getting shocked by the chemical secretion caused by the stress,” Opata said.
Essentially, all humans respond to infections differently. Despite having been exposed to a wide variety of pathogens over their lifetimes, elderly people’s immune systems are not as effective as people in their 20s or 30s.
“[The] thymus (a gland that is part of the immune system) produces antibodies that [interact with other cells to help fight infections]. For older people, their thymus is small. It shrinks as you grow older. In your early 20s, the thymus is big, and that is when your immune system is educated on how it will respond to infections,” Opata said.
Infections in those with pre-existing conditions can also trigger serious systems since the immune system is already compromised.
“If they have a pre-existing condition, like diabetes or HIV, the immune system is already trying to overwork, so they are immunocompromised. In that case they will have a severe response as someone who is immunocompetent in whom things are working much better. Some people, where they have a deficit in the cells’ ability to respond to different infections, that will also lead to a lower immune response, so there will be an increase in viral load as opposed to their immune system being able to be activated to get rid of the infection,” Opata said.
Opata grew up in Kenya and saw firsthand the effects of how malaria varied among the country’s youth. Infants became infected with malaria at far higher rates than children who were just a few years older. Opata began studying biology to find out why this was the case.
“I related it back to when I was young, but as you grow older after [age] 5 or 6 you are not as susceptible to death as children who are below four years. After you are infected several times, every infection you get you get an induction of the immune response and you build different populations of the immune cells that protect you as opposed to people that are not exposed to infections,” Opata said.
Meanwhile, Opata remains cautiously optimistic that the novel coronavirus will be able to be eventually contained.
“Trying to control the spread will help with the management of the disease,” Opata added. “It is hard to predict when it will end. Since it is a new virus, and viruses mutate much faster, it will take a while to know what mutations can occur for the disease to be able to contained.”