The administration of Wuhan is dealing with an unparalleled medical emergency, says S.Ananthanarayanan.

The World Health Organisation convened a two day forum at Geneva to assess the level of knowledge about the new COVID-19 (Corona virus disease – 2019) to identify gaps and accelerate research needed to help stop the outbreak, which has affected thousands in the short time since Dec 2019

The Hubei province in Central China, where the city of Wuhan lies, has redefined what it considers a reportable case of the disease, so that treatment and isolation can be started early, to control severity and spread. The result was that some 13,000 new cases were reported on 12th Feb, as 33% increase over the previous day. The new policy is because lab tests to confirm cases of COVID-19 take time, says Wu Zunyou, chief epidemiologist at the Chinese Center for Disease Control and Prevention. “The clinicians in Hubei made a very strong request to modify the criteria,” because of their heavy work load and so that patients are properly isolated, he says.

Coronaviruses, so called because spiky projections on the outer surface of the virus resemble the points of a crown, are a large group of viruses that infect birds and mammals, including humans. Many coronaviruses arise in animals and evolve to infect humans. The four most common coronaviruses that affect humans, which include the viruses that cause common cold, however, appear to be native to humans, and may have evolved for efficiency in spread amongst the population, rather than virulence. This may explain why the coronaviruses that cause SARS, MERS and the current, COVID-19, which are transmitted from animals, cause more severe diseases in humans. At the same time, there is the advantage, that these virulent viruses may not have efficient means of survival and spread.

Like all viruses, the way the coronavirus acts is by injecting its genetic material into a host cell and taking over the cell’s resources for its own multiplication. The function of the host cell is thus impaired, which manifests as disease, while the virus multiplies. The projections on the coronavirus surface are shape-matches with features of host cells, which allows the viruses to ‘latch on’ to specific target cells, so that the virus DNA can flow into the host.

SARS, or Severe Acute Respiratory Syndrome, broke out in 2002-03, first in Southern China, causing 8,098 cases and 717 deaths – a 9.6% fatality rate, mostly in mainland China or Hong Kong. The symptoms were flu-like and could include fever, muscle pain, lethargy, cough, sore throat, and could lead to shortness of breath and pneumonia. Chinese researchers traced the source to horseshoe bats in caves in the Yunan province, through the intermediary of the civet group of mammals.

MERS, Middle East Respiratory Syndrome, also known as ‘camel flu’, was first detected in Saudi Arabia in 2012. The symptoms are like those of SARS and a mortality rate of about one third. The spread was thought to be from camels, but it spread between humans only on close contact and rarely outside hospitals.

The current outbreak, which is called 2019-nCoV, or novel coronavirus, has similar symptoms and can lead to severe respiratory disease, with a mortality rate of about 2%. The mortality ratio, however, would fall, now that the policy is to include, in the count of infected persons, all those who show symptoms and could be considered to have come in contact with infected persons. The number infected, however, has crossed 65,000 and there have more than a thousand fatalities.

The present methods to test patients for coronavirus infections are by analyzing respiratory specimens and serum isolated from their blood. The US Centre for Disease Control stated in a conference in Jan 2020 that it has developed an equivalent protocol. Once trials show that it works, diagnostic kits would be distributed to health care facilities in the U.S. and abroad. Turkey has announced that a fast tool that gives results with 99.6% accuracy in 90 to 120 minutes has been developed, with the help of WHO inputs.

Just as for other viral disease, no direct method of treatment is available. Those who catch a common coronavirus usually recover on their own and can ease the process by medication to relieve pain and fever, using a humidifier, taking hot showers, drinking plenty of fluids and staying home to rest. Similar regimens are used to relieve the symptoms of more severe coronavirus infections.

There are some antiviral medications, which disable viruses by interfering with their attempts to replicate in host cells, originally intended to treat Ebola and malaria, and these may show some efficacy against the novel coronavirus. Another class of drug, called "protease inhibitors," which helps to alert the immune system against viral invaders is also reported to have promise.

A candidate vaccine had been developed for SARS during the pandemic of that virus. A potential MERS vaccine also performed well in preliminary clinical trials, but neither of these has hit the market. And now, research groups around the world are racing to develop a vaccine for the novel coronavirus.

The way coronaviruses are transmitted between humans is by respiratory droplets that infected people expel when they breathe, cough or sneeze. A typical surgical mask cannot block the viral particles contained in these droplets, but simple measures — such as washing one’s hands, disinfecting frequently touched surfaces and objects, and avoiding touching one’s face, eyes and mouth — can greatly lower the risk of infection. The viruses generally cannot survive for more than a few hours on surfaces outside a human host, and the window of time within which people can pick up a coronavirus from a contaminated surface is still not properly known.

Likely to spread Experts in Harvard University feel that even with some leveling of new cases in China, it is a matter of time before the virus reaches other countries. Even Singapore, which is good at tracking the spread of infection, has found some cases that were not linked to known sources. "This is really a global problem that is not going to disappear in a week or two", a Harvard staff writer says.

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