Discovering the world's viruses before they discover us
Since the beginning of time, viruses have been threatening global populations one by one. The black death, yellow fever, Polio, Spanish Flu, SARS, MERS, Zika and today’s Covid 19 are examples of the many epidemics and pandemics that have wreaked havoc and affected the lives of many. Every time, scientists scrambled to find a vaccine for the virus. However, the damage is often already done. In the case of Covid 19, in just 10 months, more than a million have passed away and trillions of dollars have already been used to respond to the spread of the disease. Covid 19 has exposed a clear weakness in the world’s ability to respond to a global outbreak. The capacity to detect and prevent the spread of diseases.
What if we discovered these viruses before they had the chance to infect us? The more we investigate and discover, the better prepared we will be to deal with future epidemics. Perhaps even preventing them from spreading in the first place.
An estimated two-thirds of human diseases originate in animals. For instance, Measles is suspected to have been transmitted from cattle and HIV from monkeys and apes. While SARS, MERS and Ebola began when an animal pathogen was transmitted to a human. These zoonotic viruses have the potential to increase greatly as human development and industrialization increase. With a surging global population, humans encroach into natural settings where these viruses exist, clearing forests to build roads and grow crops and catching wildlife to sell and keep. It is thus more important than ever to be prepared for the potential viruses that could spark the next Pandemic.
Has anyone started research on the world’s unknown viruses?
There are several projects around the world that have begun this search. Namely…
1. Global Virome project.
The Global Virome Project works together with an international network of scientists to collect the unknown viruses lurking in nature around the world and map their genomes. This project is supported by individual scientists, as well as organisations such as Ecohealth Alliance, ProMED, HealthMap, the epidemic risk firm “Metabiota” and the US agency for International Development.
2. R and D blueprint.
The R and D blueprint was launched by the WHO, provoked by the Covid-19 pandemic. It’s purpose is to spur the development and accelerate research to prepare for possible pandemics of the future. In addition, it aims to accelerate diagnostics and vaccines for the Coronavirus and to improve the coordination between scientists and global health professionals.
PREDICT is a project that has been ongoing for the past 7 years. In this time, researchers from 30 countries have already discovered about 1,000 new viruses. In addition to this, scientists from PREDICT work with local governments and non-profits to pinpoint the areas in which people encroach into the animal world, targeting these areas for further research.
How are these projects carrying out their research?
Discovering all the viruses in the globe is nothing short of a mammoth sized task. As a result of this, scientists draw up lists of viruses to research on based on numerous factors. How infectious would this virus be? Could this virus be transmitted to humans? How often do people come into contact with these animals and their viruses? These questions aid scientists to prioritise which viruses to research on, to allow their findings to be the most advantageous in predicting the spread of the next infectious disease.
After assessing these factors, scientists from PREDICT go out into the field to take samples of faeces, urine and saliva from wild and domesticated animals, as well as people. In its 7 years of operation, PREDICT has gathered approximately 250,000 samples from 74,000 sources. Following the collection of these samples, the process below takes place in their lab.
1. A Frozen sample of animal saliva and blood, along with bacteria and viruses is used
2. Genetic material is isolated from this sample
3. A DNA primer is used to do a broad sweep for viruses from this genetic material
4. Deep sequencing is conducted, which generates millions of fragments of genetic material from the sample
5. A computer compares the nucleotide sequences in the recovered fragments of genetic material with the sequences of known viruses
6. The sequence of other viruses is compared with the new virus using “phylogenetic trees” which show evolutionary relationships
7. Data set transform into an early warning system, pointing to hot spots where pandemic pathogens may emerge
Likewise, the Global Virome Project, plans to create an algorithm to look for viruses which have the highest potential to pose a risk to humans. This will be based on the features of the virus and hosts, as well as taking into account the practices and places that could lead to the spread of zoonotic diseases.
What has already been achieved?
Although there is still much more to be understood and discovered, there have already been some scientific discoveries that can pave the way to predicting and thus combating the spread of future pandemics.
For instance, based on the genetic mapping of the samples collected, bats have been found to be major reservoirs and hosts for coronaviruses, particularly Rhinolophus and Hipposideros bats in the case of Covid 19. Other discoveries include hot spots of SARS-like viruses in Africa and Southeast Asia; a previously unknown coronavirus found in a bat that closely resembles the MERS virus; adenoviruses in rodents in the Democratic Republic of Congo; herpes viruses in macaques in Malaysia; and a novel Ebola virus in bats in Sierra Leone. In total, 949 newly identified viruses have been found.
Slowly but surely, scientific researchers have begun to assemble an encyclopaedia of viruses that pose risks to humanity, at the same time, identifying human behaviours that make us increasingly vulnerable to these viruses.
Is this enough?
There are still millions of viruses to be found, and once zoonotic pathogens have been identified, it is still difficult to pinpoint if they have the potential to cause a human epidemic. Moreover, prior knowledge does not always ensue preparation. The first Ebola outbreak occurred in 1976 and 38 years later, when the virus ignited a massive epidemic in a part of Africa, a licensed vaccine still had not been found.
Could the money spent funding programmes such as the Global Virome project and PREDICT be better used elsewhere? Some scientists argue that the mapping of viruses is futile and efforts would be better spent on stocking up on public health protections, such as vaccines and antiviral drugs.
Conversely, having a clearer picture of the viral world can help scientists understand its patterns and interactions more easily and knowing where viruses run rampant could also give the public a better idea of how to avoid contracting them in these areas. These findings could prevent millions of dollars from being used to contain an outbreak, saving money and time by predicting and understanding these diseases first. Perhaps, instead of being subject to combatting a virus after it has spread, the world could instead work together to prevent the next pandemic before it starts.