Corona Viruses on the Attack

Novel Corona Virus briefly made the newspaper headlines but was replaced by more novel news about Influenza A(H7N9) in China. In its wake it left 17 patients, including 11 deaths. To date nobody knows where or from which species the virus originated. It has been a month since the last patient was reported and the question is: where does it hide? And where does SARS hide? Or is that killer virus extinct? Don’t count on it.

Corona viruses are potentially deadly ones and to date and six Coronaviruses are known to infect humans: HCoV-229E, HCoV-OC43, SARS-CoV, HCoV-NL63, HCoV-EMC (or MERS or SARS-2 or Novel Corona Virus 2012) and HKU1-CoV.
[1,2] Human Coronaviruses (hCoVs) are responsible for respiratory tract infections ranging from common colds to severe acute respiratory syndrome. Globally, approximately 5% of all upper and lower respiratory tract infections in hospitalized children are caused by HCoV-229E and HCoV-OC43, which are known since the mid 1960s.

[3] In 2003, a third Coronavirus (SARS-CoV) was identified as the causative agent of the Severe Acute Respiratory Syndrome (SARS). Between November 2002 and July 2003, an outbreak of SARS in South China and then Hong Kong nearly became pandemic with 8,273 cases and 775 deaths worldwide (Case Fatality Rate 9.4%). Before the outbreak human Coronaviruses (HCoVs) had not been considered particularly harmful respiratory pathogens. The outbreak of SARS renewed interest in this virus family and resulted in the identification of two additional HCoVs: HCoV-NL63 and HCoV-HKU1.

[4] The first case of HCoV-NL63, was reported[1] in 2004 in The Netherlands. This fourth Coronavirus was isolated from a 7-month-old child suffering from bronchiolitis and conjunctivitis.

[5] The fifth, HCoV-HKU1, was detected[2] in an adult with chronic pulmonary disease in Hong Kong in 2005.

[6] The next, Human Coronavirus-Erasmus Medical Center (HCoV-EMC) is perhaps better known as Middle East Respiratory Syndrome-related coronavirus (MERS-CoV. It was first discovered in a Saudi Arabian man who died in early 2012. To date, a total of 2538 cases, including 871 deaths have been reported. (Case Fatality Rate 34.3%).

[7] Swine Acute Diarrhea Syndrome Coronavirus (SADS-CoV) is related to Rhinolophus Bat Coronavirus HKU2. Piglets less than 5 days old die with a probability of 90%. SADS-CoV was identified during the SARS outbreak in Guangdong 2018 onwards, where it caused the death of more than 24,000 piglets on 4 farms. Current research says that - at the moment - it cannot infect humans.

Should we forget about Coronaviruses? No, we should rather be hypervigilant because more variants may lurking somewhere to infect us and possibly cause a deadly pandemic.

[8] Then, late 2019, a really scare novel Coronavirus was emerging in the Chinese city of Wuhan. After some political discussions it was decided to call the virus CoVid-19. We probably should have called the disease Wuhan Respiratory Syndrome (WuRS), but decided on SARS-2. The rest, as they say, is history.

[1] Van der Hoek et al: Identification of a new human coronavirus in Nature Medicine - 2004 
[2] Woo et al: Characterization and complete genome sequence of a novel coronavirus, coronavirus HKU1, from patients with pneumonia in Journal of Virology - 2005

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