• An Overview of Novel Corona Virus Disease (Covid-19)
  • Saman Hakimian,1 Mohammad Shayestehpour,2 Shaghayegh Yazdani,3,*
    1. M.sc student in Microbiology of Pathogenic Microbes Islamic Azad University Central Tehran Branch
    2. Autoimmune Diseases Research Center, Kashan University of Medical Sciences, Kashan, I.R. Iran
    3. Department of Microbiology, Faculty of Advanced Science & Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran


  • Introduction: 2019-nCoV is the third coronavirus to cross species to infect human populations in the past two decades. The previous two coronavirus are the severe acute respiratory syndrome coronavirus (SARS-CoV) outbreak in 2002 and the Middle East respiratory syndrome coronavirus (MERS-CoV) outbreak in 2012. The world has seen the onset of a pandemic of a new infectious disease from December 2019. This has been formally named as the CoronaVirus Infectious Disease (COVID)-19 by a consensus group of WHO experts. Numerous clusters of patients started to surface in Wuhan, Hubei Province, China in mid December 2019. They presented with features of a viral respiratory illness with complaints of fever, cough, headache and breathlessness. Some of the patients had evidence of respiratory failure, shock, acute respiratory distress syndrome (ARDS) and sepsis. Laboratory tests were not detection various respiratory viruses, bacteria or fungal pathogens. A genome sequencing of the respiratory tract samples from these pneumonia patients ultimately led to the isolation of a new novel beta-coronavirus which was initially called “Wuhan virus”, novel coronavirus (nCoV-2019) and later severe acute respiratory syndrome (SARS)-2 coronavirus.
  • Methods: The confirmation of clinical diagnosis for COVID-19 can be done by certain laboratory tests. WHO released its interim guidelines for laboratory biosafety and prioritized laboratory testing strategy on 19 and 22 March 2020. Real-Time Reverse transcriptase (RT)-Polymerase chain reaction (PCR) is used for detection of virus. Various biological samples like nasopharyngeal swabs/washes/ aspirates, sputum, BAL etc. can be tested for the presence of virus. Gene targets in N gene, ORF1ab, nucleoprotein, RdRP, spike protein have been used for detection of the virus. Presently various commercial kits for detection of the virus have been validated. They employ these targets for detection of the virus by real time reverse transcription polymerase chain reaction (RT_PCR). In 2nd or 3rd week of illness, various antibodies have been detected in the convalescent serum of the donors. 32 Rapid diagnostic test kits have been recently developed. They can detect the SARS-CoV-2 in few hours and can be used as screening tests in certain hot-spot areas of the epidemic. These tests have an accuracy of 95% for detection of infection (nasal/throat swabs) and meet various quality control standards as per WHO. They can be used at various points of patient care and no transportation of samples is required. However the test results by these rapid diagnostic kits need to be confirmed by RT-PCR for SARS-CoV-2
  • Results: Both SARS-CoV and SARS-CoV-2 are CoVs; hence, the treatment strategies of SARS could be relevant for COVID-19. In 2003, SARS was mainly treated by isolation of the patients, hormones treatment, antiviral and symptomatic treatments, and many drugs such as glucocorticoid and interferon.Now, isolation, antiviral, and symptomatic treatments are still mainly adopted for COVID-19 treatment. As effective drugs for SARS, hormones and interferons can also be used to treat COVID-19. Lopinavir is one kind of protease inhibitor used to treat HIV infection, with ritonavir as a booster. Lopinavir and/or ritonavir has anti coronavirus activity in vitro. Hong Kong scholars found that, compared with ribavirin alone, patients treated with lopinavir/ritonavir and ribavirin had lower risk of acute respiratory distress syndrome (ARDS) or death caused by SARS-CoV. Lopinavir/ritonavir has also been clinically tested in treatment of COVID-19, and showed wonderfully effective treatment for some patients, but the general clinical effect has not been determined . More effective treatments are still under continuing exploration.The first patient in the US had been trial-treated with intravenous remdesivir (a novel nucleotide analogue prodrug in development) due to a severe infection. No adverse reactions were observed during the administration, and the patient’s condition was effectively improved.
  • Conclusion: Coronavirus infections have lead to few epidemics and a new pandemic in last 2 decades. The infections vary in clinical manifestations from self limiting viral respiratory tract infections or gastroenteritis to severe form like the SARS-CoV-1, MERS and the recent SARS-CoV-2 infections. These have led to a significant morbidity and mortality and a global economic crisis. Newer developments in therapeutics, preventive therapy in the form of chemoprophylaxis and vaccines are underway. Newer information about the molecular mechanisms, clinical manifestations, epidemiological pattern and preventive public measures is available each week in all the scientific or medical journals.
  • Keywords: Acute Respiratory Syndrome-Corona Virus-Lungs-Sars-Cov2-ORF1lab