Guest column/Coronavirus: A primer
A minimum of 30,000 different virus isolates are known and belong to 71 family groupings. There are 21 families of viruses that infect humans. A virus family is characterized by RNA or DNA genetic material. Viruses cannot survive independently.
The virus can only survive in a host cell. The host may be human, animal, plant, fungus, or bacteria A virus may exist in a host cell and not cause any visible sign of illness. During replication of the viral genetic material in the host cell, “sleeping” sequences of genetic material can be opened.
This added genetic material can change the virus. Most of the time, this new genetic sequence is of no added benefit for survival of the virus. However, sometimes the added sequence is beneficial to the virus: Faster replication, easier attachment to host cells and transmission from one species to another.
Today, information about coronavirus can be found in every type of media. The world is focused on a global outbreak of a disease process called COVID19. COVID19 is caused by the beta form of the coronavirus. There are seven strains of coronavirus known to cause disease in humans. Four of these strains are the alpha form, and three strains are in the beta form. The world has experienced two other outbreaks of beta coronavirus. The first was in 2002 when severe adult respiratory syndrome was first noted in a Chinese province. This beta coronavirus originated in bats and transmitted the virus to another species — the skivat cat. The skivat cat transmitted the virus to humans. The mortality rate for SARS was 9 percent to 10 percent.
The second outbreak of a beta coronavirus occurred in 2012 with Middle Eastern respiratory syndrome. MERS originated in camels with transmission to humans. The mortality rate for MERS was at least 36 percent and in some reports listed as being close to 50 percent.
That brings us to the present with the novel (new) third beta coronavirus causing the disease COVID19. The animal (possibly a bat) to human transmission first occurred in the Chinese city of Wuhan, home to 11 million people. The mortality rate for COVID19 is estimated at 2 percent to 2.5 percent.
Dr. Anthony Fauci is the leader of the epidemiology and infectious disease division at the National Institute of Health. Fauci noted, historically, the coronavirus family was characterized by mild upper respiratory symptoms. With SARS in 2002 and MERS in 2012, the symptoms progressed to lower respiratory involvement with pneumonia and respiratory failure. Unlike SARS and MERS, person-to-person spread of COVID19 appears to be efficient, but the disease symptoms are mild to moderate with cough, runny nose and fever in some patients. COVID19 is not a transmission risk before symptoms appear.
COVID19 symptoms can progress to pneumonia with secondary respiratory failure and death. As with all respiratory viruses, the elderly, the immunocompromised and people with underlying medical issues, especially lung disease, are at risk for severe illness. The same is true for influenza, another respiratory virus which is actually increasing in case numbers at this time.
Dr. Timothy Brewer, a professor of epidemiology and medicine at UCLA, notes there is no value in panic. This is a respiratory virus, and the same precautions should be followed for all respiratory viruses. The precautions are: No. 1, wash your hands with soap and water frequently. No. 2, make sure your coughs and sneezes are covered at least with the midarm area followed by washing your hands or using a high-alcohol concentration hand sanitizer. And, No. 3, stay home if you are ill. The Ohio Department of Health and the Centers for Disease Control and Prevention give the same advice.
In the United States, 15 cases of COVID19 were diagnosed with the initial surveillance practices put in place by the CDC. Two cases of person-to-person transmission have been identified, and both involve spouses. A third person recently tested positive in California, and investigation of exposure is pending. Of the hundreds of people repatriated from China, three people tested positive. Forty-four of the repatriated 285 passengers stranded on a cruise ship also are positive. The total cases for the U.S. are 62 as of Saturday, and these numbers are updated daily. Several deaths have been reported in the United States.
Mainland China has reported 80,000 cases with 2,800 deaths. China has granted the World Health Organization limited access to the country. The CDC and NIH currently are denied access, so information is limited about the total scope of disease at the point of origin in China.
In Jefferson County, Sam Ivkovich, the public health emergency preparedness coordinator, hosted a mock multidisciplinary drill involving the scenario where a novel virus was identified in a community. The drill, held in October, involved first responders, Trinity Health System, Franciscan University, Harrison County Public Health Department and the Jefferson County Health Department.
The exercise included initial presentation, screening criteria, personal protective equipment, ER logistics, availability of hospital beds and channels to procure temporary hospital beds, isolation procedures and treatment options.
The novel virus in the drill was an influenza virus, so vaccination also was a topic. The drill illustrated the county plan to handle an outbreak and the coordination of services between the multidisciplinary group. Eight weeks after this drill, news of the novel beta coronavirus was reported. At this time, there are unprecedented scientific strides involving the CDC and NIH. Gilead Pharmaceutical is ready to trial a medication, Remdesivir, and a vaccine should be ready for phase 1 trials in a month. These strides are unlikely to benefit the current situation, but if there is another new beta coronavirus, the benefits will be seen.
Travel to Mainland China is still under an advisory alert, and travelers from China are restricted entry into the United States. Since other countries are seeing an increase in cases, it is likely that the U.S. will see further cases secondary to travel outside of the country. At this point, the current interventions have produced containment.
Again, the best precautions remain education, washing your hands frequently, covering your mouth and nose when you sneeze or cough and staying home if you are ill. Also, be aware of your surroundings. Historically, novel (new) respiratory viruses are characterized by widespread outbreaks. The most frequent outbreaks are attributed to the influenza respiratory viruses.
In 2009, the U.S. saw the emergence of a novel influenza A virus, H1N1. From April 12, 2009, to April 10, 2010, the CDC estimated 60.8 million cases in the U.S, 274,304 hospitalizations and 12,469 deaths. Globally, the influenza A H1N1 mortality was greater than 152,000 people. The influenza A, H1N1, remains a component of the flu vaccine to this day.
Statistics are updated every day, and more knowledge is gained about this new coronavirus on a daily basis. The CDC remains a lead for surveillance and guidelines. Helpful websites include cdc.gov and odh.gov.
(Culp is medical director of the Jefferson County Health Department.)