The COVID-19 Outbreak: The Knowns and Unknowns

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The COVID-19 Outbreak: The knowns and unknowns By Rahwa A. Osman, Jennyfer Ambe, and Laetitia Diatezua

CDC: confirmed cases as of Feb. 10th 2020 The COVID-19, more commonly known as the Wuhan Coronavirus was first identified as the agent causing a mysterious respiratory illness in Wuhan, China with a complete viral DNA sequence submitted to the National Institute of Health database identifying it as a coronavirus related to the causative agents of the Severe Acute Respiratory Syndrome (SARS-COV) and Middle Eastern Respiratory Syndrome (MERS-COV) outbreaks in recent history. The initial reports noted that there were no human-tohuman transmissions but the cases were linked to the Wuhan seafood market, identifying it as the epicenter of the outbreak and animals as a potential source. Since then, human-to-human transmission has been reported in United States, Germany, Thailand, and Vietnam.

Phylogenetic analyses done by the scientific community suggest that the virus originated in snakes and bats. A previous claim that this virus was genetically

engineered to include HIV fragments was discredited considering that the protein regions analyzed were too short to be specific and could potentially be similar to a large number of viruses resulting in false positives.

The future of this outbreak is determined by the transmission rate and incubation time.

The former is still a mystery with very few human-to-human cases reported. The latter, defined as the period between exposure and the appearance of symptoms is estimated to be 2-11 days, which is why known exposed individuals with no symptoms are in isolation and under observation for 2 weeks. The clinical symptoms include fever, coughing and shortness of breath.

In the last 17 years, there have been several outbreaks in China including Avian Influenza (H5N1 in 2003, H7N9 in 2013, H5N6 in 2016-2017, H7N4 in 2018), SARSCOV in 2003, Brucellosis in 2012, and COVID-19 outbreaks. The last few disease outbreaks have been zoonotic, meaning, an animal virus mutated and adapted to infect humans. It is also a testament of the usual close-interaction between animals and humans in China such that the ideal environment for animal viruses adapting to humans is created.

The resilience of the public healthcare system in line with proficiency of the disease surveillance both in humans and animals is tested by an outbreak. Practical outbreak preparedness dictates how quickly the outbreak can be contained. Early detection and preventative measures can be implemented with a coordinated effort of animal and human disease surveillance. This current outbreak has highlighted gaps in early disease detection, earlier local and global communication with the public to notify of best practices and relevant ongoing updates to avoid hysteria and misrepresentation.

With an extensive experience in mitigating outbreaks, it is a lingering wonder if the lessons and recommendations from the past outbreaks were applied to the current COVID-19 outbreak. For example, it took nearly six months for the viral DNA of the SARS-COV coronavirus to get sequenced and characterized. Seventeen years later, both technology and best practices were applied to quickly identify the COVID-19 virus in under a month and provide information for vaccine development. Diverse strategies have been applied in different affected countries. As the most affected country, China has applied the most stringent strategies including school closure, restricted inter-provincial movement isolating cities to contain the outbreak. Putting an entire city under quarantine, as has been done in Wuhan, is a first of its kind and a lesson in progress. This intervention is perhaps very effective in reducing transmission to susceptible individuals in the short term but it’s doubtful that it can be sustained long term without serious consequences. To address potential shortage of supplies, stores are providing 50% more of food and other necessities while restricting only one

person per household for daily shopping. Although health care professionals were initially stifled from sharing the known facts about this mysterious virus with the public, a significant effort is being made to notify the public daily about new cases, but also recovery of patients through an online daily briefing from the National Health Commission. The U.S has implemented alternate measures including restricting entry of most foreign nationals who have recently visited China and imposing quarantine of up to 2 weeks for U.S citizens, who have recently visited the Hubei province. Other countries have implemented different strategies including closing their borders to foreign tourists (North Korea) while countries like Canada have chosen active surveillance and public health screening at airports over travel bans. Furthermore, several airlines worldwide have suspended flights to and from China in an effort to reduce the global spread of the virus. Although countries have mobilized these efforts, an unknown transmission rate makes predicting the outbreak’s severity and recommending infection control measures very challenging. As of Feb 10th, there have been 42,638 confirmed cases, 1016 deaths and 3996 recovered patients in 31provinces of Mainland China. However, with increased global trade and transportation, 28 other countries including the U.S and Canada have also reported confirmed imported cases of COVID-19 within a month.

Outbreaks are often eliminated through multiple measures including eliminating reservoirs, vaccination of high-risk groups and cautionary measures such as avoiding large gatherings, washing hands frequently and coughing into sleeves. Outbreaks also serve as an opportunity to review common local practices that increase risks of potential outbreaks. For instance, frequent close-interactions between farming/wild animals and humans pose a risk of zoonotic disease outbreaks, which makes concerted active surveillance of human and animal diseases not only essential but also critical.

The source of the virus in the current outbreak is still a contentious issue as are the reservoirs. Vaccine development is hopeful but slow, while cautionary practices such as wearing masks if sick and washing hands frequently can immediately be applied to intercept transmission of this virus.