There has been a tremendous amount of misinformation about the recent corona-virus infection. I’ve had so many patients ask about it, and come in to my office wrapped in cellophane and latex, that I want to clarify and give some basics. This virus is not benign. Yet, we also shouldn’t feel inclined to panic. Recent data published in the first week of March demonstrates that it is different from Influenza. It’s important to understand that it has the potential to be twice as aggressive as the flu, but these are still preliminary assessments. Fear mongering is the last thing that I want to do with this article, and it is essential that we all understand what has crossed our shores in the last two weeks.
What is it?
Coronaviruses are viral pathogens (microorganisms that can cause disease) that affect humans and animals. There are over 50 forms of viral RNA coronaviruses that we know about. Four of these strains are infective to humans.
At the end of 2019, a variant of coronavirus was identified as the cause of a cluster of patients with severe pneumonia in Wuhan, a city in the Hubei Province of China. The viral strain spread rapidly throughout China and was followed by increased numbers of cases throughout other countries of the world. In February 2020, the World Health Organization (WHO) designated the disease COVID-19, which stands for coronavirus disease 2019. It has been designated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and it was previously referred to as 2019-nCoV.
Epidemiology
At the end of 2019, more than 80,000 cases have been reported in China. As of the writing of this e-mail (March 13, 2020), there have been almost 140,000 cases of the virus world wide and 5,120 deaths worldwide. There have been 1832 confirmed cases in the US and 41 deaths as of today. The only country not reporting cases of COVID-19 is Antarctica.
There are currently nine confirmed cases of COVID-19 in Arizona. As of this morning 115 people have been tested for the virus in Arizona. 82 cases are negative and 24 are still pending result. Recent data reveals that this virus has the capability of doubling in spread person-to-person every four days.
What does this mean? If we are not careful in prevention of transmission, 4 million people in the United States will have the virus by May 1st and with our obese and immunocompromised population, conservative estimates of 240,000 to as high as 800,000 fatalities are possible.
Transmission of this virus is still not completely understood. Person-to-person transmission has been the main mode of transmission via respiratory droplets identifiable within 8 feet of the infected individual. This transmission can occur through sneezing, coughing, talking or direct contact with mucous membranes. If a person touches an infected surface and then touches their eyes, nose, or mouth, transmission can occur.
Because of the uncertainty in transmission, airborne precautions have been recommended in some countries. Transmission of the virus by asymptomatic patients has also been documented, however, the extent to which this occurs remains unknown 1-5.
SARS-CoV-2 RNA has been detected in blood and stool specimens and live virus has been cultured from stool in some cases 6. However, fecal oral transmission did not appear to be a significant factor in spread of the infection 7.
Virology
Genomic sequencing and analysis indicate that the coronavirus is a beta-coronavirus in the same subgenus as severe acute respiratory syndrome (SARS) virus (as well as several bat coronaviruses), but in a different clade. The virus uses the same receptor that SARS uses, the angiotensin-converting enzyme 2 (ACE2), for entry into the cell 8.
Clinical Features
The incubation period for COVID-19 is thought to be around 14 days following exposure, in most clinical cases seen since 2019, it occurs within four to five days after exposure. The median incubation period in a recent study of 1099 patients was four days 9.
Most infections are not severe, however, many patient in China experienced critical illness.
- 81% had mild symptoms
- 14% had severe disease with pneumonia
- 4% had critical respiratory failure, shock or multi-organ dysfunction
- 3% overall fatality was reported overall. No deaths occurred in the non-critical cases.
Any age group can be susceptible to the infection, however middle age and older adults are most commonly affected. Symptomatic infection in children appears to be uncommon. When children are affected it appears to be mild. In China, only 2% of the infections were in individuals younger than 20 years old. In children, 80% had a fever which resolved in 24 hours, 60% had a cough and 40% had a sore throat. None of the children studied required supplemental oxygen 10.
The recent cruise ship outbreak last month resulted in 17% of those on board with the infection. 619 passengers were confirmed to have COVID-19 and half of the confirmed cases were asymptomatic at the time of the diagnosis on February 20th, 2020 11.
Even patients with asymptomatic infection may have objective clinical abnormalities. In a study of 24 patients with asymptomatic COVID-19 infection, all who underwent computed chest tomography (CT), 50% had a ground-glass opacity or patchy shadowing and an additional 20% had imaging abnormalities. Five patient developed low-grade fever with or without typical symptoms a few days after diagnosis 5.
Common Clinical Features
The most common clinical features reported in a study of 138 patients have been 12:
- Fever – 99%
- Fatigue – 70%
- Dry Cough – 59%
- Anorexia (loss of appetite) – 40%
- Myalgia (muscle aching) – 35%
- Shortness of breath – 31%
- Sputum production with cough – 27%
Shortness of breath seemed to develop after about 5 days. Acute respiratory distress developed in 20% of patients and mechanical than ventilation was necessary and 12% of the patient’s.
Fever may not always be present. Other less common symptoms are headaches, sore throat, and runny nose. Some patients have had some gastrointestinal symptoms like nausea and/or diarrhea, however, these seem to be relatively uncommon.
Recovery time appears to be 2 weeks for mild infection in 3-6 weeks for more severe disease 13.
Lab Findings
Laboratory findings in patients with COVID-19 reveals a variable white blood cell count.
Low white blood cells, high white blood cells, and low lymphocytes have all been reported. However, lymphopenia (low lymphocyte count) appears to be the most common. Elevated liver enzymes have also been described in number of cases. On admission, many patients with pneumonia nave normal procalcitonin levels, however, those who required intensive care treatment have had procalcitonin levels elevated.
High D-dimer and severely low lymphocyte count seems to be most common in those associated with severe cases and death.
Lab changes can occur up to 10 days after initial onset of symptoms. However, CT findings of the chest have been identified in up to 70% of patients before the onset of physical symptoms.
Evaluation and Diagnosis
Initial management should focus on early recognition of those suspected with the virus. COVID-19 should be suspected in any one with fever and or lower respiratory tract symptoms with any of the following in the last 2 weeks:
- Close contact with a confirmed or suspected case of COVID-19
- Residence or Travel to an area with widespread community transmission (China, South Korea, Italy, Iran, Japan).
- Potential exposure through attendance of an event where COVID-19 has been reported.
In office testing for the virus can be completed with a nasal swab or nasal washings for SARS-CoV-2 RNA polymerase chain reaction frozen sample sent to qualified lab. Our office has already tested two people that have been negative.
Prevention of Transmission
Currently standard, contact, and droplet precautions in addition to eye protection is the CDC recommendation. Those suspected to have COVID-19 should wear a mask and get tested with their medical provider. Simple surgical masks prevent those suspected from transmitting droplet particles to others around them.
The N95 medical masks are the only effective masks to prevent inhaling the droplets and these are in short supply currently. Use of these masks should be based on the regional exposure risk and protocols of the hospital or clinic.
It is unknown whether the virus can be transmitted through breast milk; however, droplet transmission could occur through close contact during breastfeeding. America College of Obstetricians and Gynecologists (ACOG) recommends that mothers with confirmed COVID-19 or symptomatic mothers with suspected COVID-19 take precautions to prevent transmission to the infant during breastfeeding (including assiduous hand hygiene and using a facemask) or consider having a different individual feed expressed breast milk to the infant.
Environmental Disinfection
To prevent the spread of the virus, routine cleaning and disinfection procedures are appropriate for COVID-19 virus.
It is unknown how long SARS-CoV-2 can persist on surfaces; other coronaviruses have been tested and may survive on inanimate surfaces for up to six to nine days without disinfection. In a study evaluating the survival of viruses dried on a plastic surface at room temperature, a specimen containing SARS-CoV (a virus closely related to SARS-CoV-2) had detectable infectivity at six but not nine days. However, in a systematic review of similar studies, various disinfectants (including ethanol at concentrations between 62 and 71 percent) inactivated a number of coronaviruses related to SARS-CoV-2 within one minute 14,15.
Preventing Transmission and Exposure in the Community
- Diligent hand washing with warm water and soap, particularly after touching surfaces in public. If soap and water are not available, use of hand sanitizer that contains at least 60 percent alcohol is a reasonable alternative if the hands are not visibly dirty.
- Respiratory hygiene (covering the cough or sneeze).
- Avoiding touching the face (in particular eyes, nose, and mouth).
- Avoiding crowds (particularly in poorly ventilated spaces) if possible and avoiding close contact with ill individuals.
- Cleaning and disinfecting objects and surfaces that are frequently touched. The CDC has issued guidanceon disinfection in the home setting; a list of EPA-registered products can be found here.
These measure are particularly important and recommended for older adults (over 55 years old), those that are obese and those with chronic medical conditions. In my office, we have a telemedicine visit option (however, it is not covered by insurance presently).
Individuals who are ill should stay at home from school or work.
If SARS-CoV-2 is prevalent in the community, residents should be encouraged to practice social distancing by staying home as much as possible.
References:
- Rothe C, Schunk M, Sothmann P, Bretzel G, Froeschl G, Wallrauch C, Zimmer T, Thiel V, Janke C, Guggemos W, Seilmaier M, Drosten C, Vollmar P, Zwirglmaier K, Zange S, Wölfel R, Hoelscher M, Transmission of 2019-nCoV Infection from an Asymptomatic Contact in Germany. N Engl J Med. 2020;382 (10):970. Epub 2020 Jan 30.
- Kupferschmidt K. Study claiming new coronavirus can be transmitted by people without symptoms was flawed. Science. February 3, 2020. https://www.sciencemag.org/news/2020/02/paper-non-symptomatic-patient-transmitting-coronavirus-wrong (Accessed on February 04, 2020).
- Yu P, Zhu J, Zhang Z, Han Y, Huang L. A familial cluster of infection associated with the 2019 novel coronavirus indicating potential person-to-person transmission during the incubation period. J Infect Dis. 2020.
- Bai Y, Yao L, Wei T, Tian F, Jin DY, Chen L, Wang M, Presumed Asymptomatic Carrier Transmission of COVID-19. 2020.
- Hu Z, Song C, Xu C, Jin G, Chen Y, Xu X, Ma H, Chen W, Lin Y, Zheng Y, Wang J, Hu Z, Yi Y, Shen H. Clinical characteristics of 24 asymptomatic infections with COVID-19 screened among close contacts in Nanjing, China. Sci China Life Sci. 2020.
- Centers for Disease Control and Prevention. Interim Clinical Guidance for Management of Patients with Confirmed 2019 Novel Coronavirus (2019-nCoV) Infection. Updated February 12, 2020. https://www.cdc.gov/coronavirus/2019-ncov/hcp/clinical-guidance-management-patients.html (Accessed on February 14, 2020).
- Report of the WHO-China Joint Mission on Coronavirus DIsease 2019 (COVID-2019). February 16-24, 2020. http://www.who.int/docs/default-source/coronaviruse/who-china-joint-mission-on-covid-19-final-report.pdf (Accessed on March 04, 2020).
- Zhou P, Yang XL, Wang XG, Hu B, Zhang L, Zhang W, Si HR, Zhu Y, Li B, Huang CL, Chen HD, Chen J, Luo Y, Guo H, Jiang RD, Liu MQ, Chen Y, Shen XR, Wang X, Zheng XS, Zhao K, Chen QJ, Deng F, Liu LL, Yan B, Zhan FX, Wang YY, Xiao GF, Shi ZL. A pneumonia outbreak associated with a new coronavirus of probable bat origin. 2020.
- Guan WJ, Ni ZY, Hu Y, Liang WH, Ou CQ, He JX, Liu L, Shan H, Lei CL, Hui DSC, Du B, Li LJ, Zeng G, Yuen KY, Chen RC, Tang CL, Wang T, Chen PY, Xiang J, Li SY, Wang JL, Liang ZJ, Peng YX, Wei L, Liu Y, Hu YH, Peng P, Wang JM, Liu JY, Chen Z, Li G, Zheng ZJ, Qiu SQ, Luo J, Ye CJ, Zhu SY, Zhong NS, China Medical Treatment Expert Group for Covid-19. Clinical Characteristics of Coronavirus Disease 2019 in China. N Engl J Med. 2020.
- Cai J, Xu J, Lin D, Yang Z, Xu L, Qu Z, Zhang Y, Zhang H, Jia R, Liu P, Wang X, Ge Y, Xia A, Tian H, Chang H, Wang C, Li J, Wang J, Zeng M. A Case Series of children with 2019 novel coronavirus infection: clinical and epidemiological features. Clin Infect Dis. 2020.
- Japanese National Institute of Infectious Diseases. Field Briefing: Diamond Princess COVID-19 Cases, 20 Feb Update. https://www.niid.go.jp/niid/en/2019-ncov-e/9417-covid-dp-fe-02.html (Accessed on March 01, 2020).
- Wang D, Hu B, Hu C, Zhu F, Liu X, Zhang J, Wang B, Xiang H, Cheng Z, Xiong Y, Zhao Y, Li Y, Wang X, Peng Z. Clinical Characteristics of 138 Hospitalized Patients With 2019 Novel Coronavirus-Infected Pneumonia in Wuhan, China. 2020.
- WHO Director-General’s opening remarks at the media briefing on COVID-19 – 24 February 2020 https://www.who.int/dg/speeches/detail/who-director-general-s-opening-remarks-at-the-media-briefing-on-covid-19—24-february-2020 (Accessed on February 26, 2020).
- Kampf G, Todt D, Pfaender S, Steinmann E. Persistence of coronaviruses on inanimate surfaces and their inactivation with biocidal agents. J Hosp Infect. 2020;104(3):246. Epub 2020 Feb 6.
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