Rising fear of the novel coronavirus (2019-nCoV) that infected at least 12,000 people and killed around 305 within a month has led China to lock down entire provinces and the US and Australia to temporarily ban the entry of foreigners who have recently travelled to China.
Even asymptomatic people can carry the infection to other regions and countries, which makes it necessary to quarantine Indian students evacuated from China for at least two weeks till they are free of the infection.
Coronaviruses, however, do not survive for long on objects such as packages and letters, according to the World Health Organisation (WHO), which makes it safe to remote-control businesses from the safety of your home or office outside China.
The numbers are much higher than officially recorded, suggests a new modelling study published in The Lancet on Friday, which estimates that coronavirus (2019-nCoV) may have affected up to 75,800 people in Wuhan by January 25. And with dozens of infected persons leaving the city before the shutdown, local outbreaks are waiting to happen in Guangzhou, Beijing, Shanghai and Shenzhen, which together account for over half of all outbound international air travel from China, found the study, which used mathematical modelling based on officially reported cases, domestic and international travel (train, air, road), and the assumption that the 2019-nCoV serial interval estimate (time taken to infect other people) is the same as severe acute respiratory syndrome (Sars-CoV), which is also a type of coronavirus.
“If the transmissibility of 2019-nCoV is similar nationally and over time, it is possible epidemics could be already growing in multiple major Chinese cities, with a time lag of one to two weeks behind the Wuhan outbreak. Large cities overseas with close transport links to China could potentially become outbreak epicentres because of substantial spread of pre-symptomatic cases,” said lead author Professor Joseph Wu from the University of Hong Kong.
Historically, the other two novel coronaviruses that have emerged as global health threats since 2002 have not affected India despite causing outbreaks in neighbouring countries. The Sars-CoVspread to 37 countries and caused more than 8,000 infections and 800 deaths, mostly in south-east Asia in 2002, while Middle East respiratory syndrome coronavirus (Mers-CoV; in 2012) spread to 27 countries and infected 2,494 people and caused 858 deaths. India remained unscathed. Like 2019-nCoV, both viruses cause fever and moderate-to-severe respiratory symptoms that may lead to pneumonia.
“Both Sars-CoV and Mers-CoV have low potential for sustained community transmission, so outbreaks tend to die out if managed well. But coronaviruses also have superspreading ability to cause large clusters of infection from a single case, which makes quarantining infected people for two weeks till they are infection free non-negotiable,” said a health ministry official, who did not want to be named.
Coronavirus (2019-nCoV): What to expect once symptoms begin
Common symptoms: Fever (98% of patients), cough (75%), myalgia or fatigue (44%), and others
Day 0: onset of symptoms
Day 7: hospitalisation
Day 8: shortness of breath,
Day 9: acute respiratory distress syndrome
Day 10-11: ICU admission