Understanding the World of Viruses and Outbreaks
By Robert Bernstein
SEC - A Viral Lecture: Understanding the World of Viruses and Outbreaks - Dr. Carolina Arias, Assistant Professor, UCSB Department of Molecular, Cellular and Developmental Biology 3-11-20.
Dr Carolina Arias specializes in virus-host interactions in her UCSB research lab. We were fortunate that she was able to speak to us at the Science and Engineering Council about the current situation with the COVID-19 coronavirus.
Here are my photos from her talk.
Arias explained that we are exposed to viruses every day. They are constantly traveling the world. She expressed frustration that diseases like measles are on the rise due to misinformation by "anti-vaxxers".
She noted that Ebola is still happening. And she reminded us of the harm done by the Zika virus during its peak 2015-2017.
"Don't Panic!" That was her message that she took from "The Hitchhiker's Guide to the Galaxy" and wanted to convey to us.
Panic can be more damaging than the disease and it can make people do crazy things. We are seeing this now with the bizarre hoarding behavior in stores of items like toilet paper.
Arias offered this quote from two times Nobel Laureate Marie Curie: "Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less."
Unfortunately, at this time we don't understand much. The situation is rapidly evolving. This virus was first discovered in December 2019.
So, what is a virus? Arias noted that she has two young children and they are constantly carrying them! A virus is a bit of genetic material encased by proteins.
She offered an image of an influenza virus.
Viruses are not living organisms. The Oxford English Dictionary says, "Life is the condition that distinguishes us from inorganic matter. The capacity for growth, reproduction and continual change preceding death."
Viruses need a host. Viruses are "obligate intracellular parasites". The virus hijacks the host cell to turn it into a virus factory. They are "pirates" of the cell and often kill the cell when they are done with it.
Viruses infect all kinds of organisms. Farm plants and animals, included. China last year had a pig virus that killed most of the pigs in China.
Have you ever seen a blue "roly poly" bug (or pillbug)? The blue is caused by an iridovirus that forms crystals on the surface.
Viruses can infect tobacco, yeasts, amoebas and bacteria. We are full of viruses that infect the bacteria in us. They outnumber the bacteria by ten to one.
Not all viruses cause disease.
Some viral diseases are common. For example, the common cold and herpes. Arias studies a specific herpes virus that infects the eye. The average adult gets 2-3 cases of the common cold each year. More for children.
We don't die of colds or herpes simplex.
Other viruses are rare. For example, rabies or West Nile Virus.
Sometimes, disease numbers rise in a certain area. This is called an "outbreak".
Last year there was a measles outbreak in Los Angeles County. One person exposed 500 people in a couple of classrooms. 100 of those could not show they had been vaccinated. It was controlled after it was identified.
Outbreaks can expand. An infected person may not be identified and may not seek medical attention.
An epidemic is defined as "an outbreak of disease that spreads quickly and affects many individuals at the same time." A pandemic is an epidemic that has affected an entire country or the entire world.
As of March 11 the World Health Organization (WHO) declared that COVID-19 is officially a pandemic. The day before it was officially calling it just an "outbreak"! Arias said that the delay in calling it a pandemic was more political than scientific.
What are coronaviruses? Coronaviruses are a large family that includes mild viruses like some common colds all the way to serious viruses like MERS.
20-30% of common colds are due to coronaviruses.
Despite some rumors, COVID-19 was not engineered in a lab! But some coronaviruses will mutate naturally.
The 2002 SARS outbreak was the first realization that coronaviruses could be serious. SARS had a 10% death rate. There were 8,000 cases of SARS. After containment there were no other cases except some sporadic ones.
The 2012-13 MERS outbreak was 30% fatal. There were 2,000 cases. Because it was so damaging to patients, most were in the hospital. They were able to infect some health care workers in the hospitals but they had little access to infecting others outside the hospitals.
COVID-19 is a bigger challenge because people can walk around infected for awhile without knowing they have it. Thereby infecting other members of the public.
This virus started out being called the "Wuhan Virus" because of where it was first observed. It was then called "Novel Coronavirus 2019". It is now called COVID-19, but the full official name is SARS-CoV-2. It is related to SARS. But it did not evolve naturally from SARS.
Coronaviruses can be spread by animals. COVID-19 started in an animal market in Wuhan, China. It began in bat populations. They don't die from it. They can in turn infect other animals that humans come in contact with more often.
In the case of SARS, the more common animal that was the intermediary was the civet cat in China. This animal was often eaten for food. The sale of civet cats was banned, but it continued in the black market.
MERS resides in dromedary camels. Human adult males are most likely to get MERS because of their interactions with these camels.
The current COVID-19 origin is still a mystery. We know it came specifically from the Wildlife Market in Wuhan. But the specific animal is not known. There was a rumor that pangolins were involved. That is now known to be incorrect.
COVID-19 is known to be carried by bats. That version is 96% similar to the human version. But the intermediary reservoir animal is not known.
The outbreak started close to New Year's Eve on December 31, 2019. It was observed to be a form of pneumonia with no known cause. The genome was sequenced and it was known in days to be a new coronavirus.
Looking back, we know that the first appearance of the first symptoms occurred in a patient in early December 2019.
Arias presented this timeline showing how fast this has happened:
December 31 – That mystery pneumonia
January 7 – Isolated with genome
January 11 – 41 were known to be infected
January 20 – First US case
January 30 – WHO declared a Global Emergenc
Arias showed graphs of cases in China and outside China. Cases in China plateaued due to massive action there. But in the rest of the world it is still on the rise.
February 26 was the first US case of unknown origin, in California. This is worrisome because it means that people may carry it with little or no symptoms.
February 29 was the first US death.
March 6 Trump signed an $8 billion emergency spending bill. This should have happened earlier according to Arias.
The availability of tests affects reported cases. Testing will be based on symptoms, not on demand. Numbers are clearly not accurate now since so little testing has been done in the US.
COVID-19 is an RNA virus. This is error prone every time it replicates. Viruses don't care if lots of mistakes are made because so many are made. This makes it easy to trace by observing mutations. The rate of these mutations allows determination of how long it has been in a given population.
It is possible to look at the outer package of the COVID-19 virus to identify it.
California is one of the most affected states so far. Mostly in the north of the state so far. Washington State and New York State are also very much affected. It will keep spreading. As of the time of her talk, there were 1,000 US cases. 31 deaths. And 15 people who recovered.
The symptoms are fever, cough and shortness of breath. That is not very descriptive. Common influenzas have the same symptoms.
2-14 days after being infected the symptoms appear.
It can be caught by being within 3-6 feet of someone with an active fever for more than two minutes. It is spread by droplets from coughing from deep in the lungs.
Just touching someone is not immediately a problem. It has to enter your body through eyes, nose or mouth. This is why it is important to wash hands frequently. Hand sanitizer is an alternative if hand washing is not possible. We unconsciously touch our faces and that is the problem. It helps to make a conscious effort not to touch our faces, but hand washing is more effective in practice.
Droplets will settle on surfaces and can spread from there. Think of it like a bad version of influenza. Surfaces can be sanitized with Clorox or Lysol.
The main complication of COVID-19 is pneumonia.
Why is it so severe? Most viruses thrive in the upper respiratory tract. This is true for the common cold and most versions of influenza.
But COVID-19 only thrives deep inside the lungs, in the alveoli. That is what it targets. This is by definition a form of viral pneumonia. Antibiotics do nothing to help.
So far COVID-19 seems to have a 2% mortality rate. In comparison SARS was 9.6% and MERS was 34%.
Pre-existing conditions make a big difference in the mortality rate for COVID-19. It is just 0.9% with none. Being old is itself a risk factor in addition to specific conditions.
There are no vaccines for this virus, nor for most viruses. Nor are there any antiviral agents for this one. In the case of influenza, it is possible to take the antiviral Tamiflu within 48 hours and it will shorten the case by about one day. There are also antiviral agents for HIV, herpes and hepatitis C.
There is an attempt now to repurpose antivirals for this disease. One that is being studied is Remdesivir. But it won't be soon enough to stop the spread for now. It has to be studied to determine if it works. If it does anything bad. And if it can be used prophylactically or if it can only be used as a treatment.
A vaccine will take a year or more to develop.
There are "super responder" patients who get the disease quickly but also clear it quickly from their bodies. It is good to study such people to get a clue about treatment. This helped with Ebola.
With regard to face masks, she advises against using them if you are healthy. You will end up putting your hands to your face more often if you are wearing a mask. That actually increases your risk of infection. Masks can be helpful if they are worn by those who are already infected to keep them from infecting others.
"Social Distancing" is effective. Avoid being close to other people. Avoid hand shaking and other unnecessary contact.
If you have a fever you should contact your health care provider. 100.4 degrees Fahrenheit is the threshold of concern. If you have a fever, please stay home.
She trusts what Anthony Fauci is saying at the Centers for Disease Control (CDC).
The CDC also offers advice on how to survive while staying home during a quarantine.
Children will be OK if they get this disease. But it is important to make sure they don't pass it along to older people who are at risk. The Swiss government opted to keep schools open so the kids are not going to stay with their grandparents!
There are many unknowns right now. We don't know how long it can be transmitted after a person has had it. It takes days to get test results even if one can get tested. It is not even known if getting the disease gives permanent immunity. And we don't know what are the long term effects on the lungs or the rest of the body from getting this disease.
Someone asked Dr Arias if she had a favorite science fiction movie that was related to epidemics. She said that in fact the movie "Outbreak" got her into the field!
In summary, she said:
Wash your hands
Protect others by staying home if you are sick
Wear a mask to protect others
Avoid groups and unnecessary touching of others
And Don't Panic!
I will add that this presentation was provided by the Science and Engineering Council of Santa Barbara. They host monthly talks on local technical innovation as well as providing scholarships and other services to encourage young people to go into science and engineering careers.
Here is more information about the Science and Engineering Council: https://www.scieng.org/