It has been reported that the coronavirus is again spreading exponentially in the North of England. In cities like Manchester and Liverpool, the infection has escalated to the level of up to 600 per ten thousand people. Hospital admissions have reached (10/10/2020) over 550 and death over 80 per day. Countries in Europe such as Belgium, Spain, France, and even Germany are reporting a resurgence in covid-19 cases after successfully slowing outbreaks early in the year. In this blog, I would like to address the worries of laymen on the effectiveness of lockdown, face mask, Covid-19 test interpretation and morphology of Coronavirus.
Should the government impose another lockdown or allow the coronavirus to run its course? The UK had a nationwide lockdown through a statute on 23rd March 2020. In China strict lockdown rules have massively reduced the virus transmission. In Singapore and other Far East countries, lockdown helped to reduce the spread. In the UK the growth reduced by 8.6%, whilst the reduction in Germany was 19.5%. In Ecuador the change after lockdown was very significant at 39% reduction. There are countries like Sweden, and South Korea where there were no lockdowns and their model of management was different from that of countries where lockdown was imposed. South Korea practised very stringent test and trace system and strictly isolated the contacts. Although Sweden regrets for not imposing lockdown like other European countries, their growth of the virus was not as exponential as in other European countries like Spain and Italy, but the country had relatively high mortality.
Right now most countries have different models of restrictions on social distancing, and socialising. In the UK, the current situation is such that the Covid-19 pandemic is going to double every three to five days, unless lockdown is imposed. There is a school of thought on allowing the pandemic to run its course infecting everyone in the country. This has the benefit of the country developing ‘herd immunity’, at the expense of having a mortality of 250000. Is that policy of allowing so many people to perish a good one, given that sooner or later coronavirus vaccine will be available? Also transmission of Covid to hundreds of thousand of people simultaneously will compromise the National Health Service (NHS) care and availability of beds. The downside of the lockdown is its impact on the physical and mental well being of the people, as well as the economy. But environmentally, lockdown helps to reduce traffic and usage of energy in the office.
Another controversial issue is wearing of the face mask which was a subject of fierce debate in the US, as president Trump loathes to wear it. As a surgeon, I am used to wearing surgical masks as long as eight hours a day. A surgical mask is a loose-fitting, disposable device that creates a physical barrier between the mouth and nose of the wearer and potential contaminants in the immediate environment. They come with or without a face shield. Surgical masks are made in different thicknesses and with different ability to protect you from contact with liquids. With regard to Covid-19 transmission, it has been proved that the wearer, of the face mask helps to reduce the virus going out in droplets or as aerosol. A droplet is a liquid particle measuring less than 500 micrometer in diameter. On coughing, sneezing or even talking these particles with coronavirus can lodge on the eyes or an area close to nostrils and mouth called philtrum. Aerosols are microscopic virus packed particle expelled from an infected persons mouth or nose. Unlike droplets, aerosols particles can remain suspended in the air for a longer time. According to the Centres for Disease Control (CDC),a recent studies indicate a significant portion of people who have COVID-19 do not show symptoms, and the virus can spread before they realise they are sick. One thing is certain, if one cannot physically keep a social distance or in an enclosed area, mask will help to reduce the transmission.There are different types of face masks, and its efficacy depends on the quality of the product and how well it is worn. The one used by the healthcare professionals are N95 respirators , which are made to fit the face of person. Washing of the N95 mask with water,reduces its efficacy by 21%!. Laymen can make their own mask. On buying masks, look for masks that are made with at least 2 layers of fabric. It should cover your nose and mouth without large gaps. The mask should have ear loops or ties so you can adjust it. The UK prime minister Boris Johnson toughened up the regulations on Covid-19 by doubling up the fine for failing to wear mask to £200 on 02/09/2020. Children under 11 years, those who are having physical or mental incapacity, and emergency workers are exempted from wearing masks in an enclosed area.
The other burning issue in the minds of laymen is testing and tracing which are the best tools to contain Covid-19. In my previous blogs I discussed about various tests, such as Polymerase Chain Reaction (PCR), DNA nudge test, Antigen test or rapid test and antibody test for coronavirus. Although the health secretary, Matt Hancock was boasting about world beating system of testing and tracing, still the UK has severe under capacity in testing and tracing. The mobile phone application ‘NHS Covid-19’ is not functioning as expected in this country. Currently 220,000 individual tests are being processed each day. The UK government wants the laboratory daily testing capacity to rise to 500,000 a day by 31 October. People with fever, having a new continuous dry cough and, or a loss of smell and taste should get tested. Either people with symptoms can book an appointment or ask for a kit to do the PCR test. The swab should be inserted 3cm deep into the nostril and twisted to get a proper specimen. After sending the swab, normally it takes 3-5 days to get the result. The result printed as ‘negative’, ‘false positive’, ‘positive’ or ‘false negative’. It has been reported that the sensitivity and specificity of PCR test is greater than 95%. Also it is estimated that 0.8% to 4% Covid-19 results are false positive, which means that patient has to unnecessarily go through the management of the pandemic, including hospitalisation and the possibility of really contracting it in the hospital Covid ward. If the report is false negative, the patient might show the symptoms of Covid-19 later, and ought to be retested and isolated. In my other blogs, I have given the details of the principles and methods of doing PCR test.
Another common question about the Covid-19 pandemic is about the survival of the coronavirus on various objects. On the human skin, it survives for nine hours and longer in colder temperature than hotter ones. Normally the virus settles on the fomites and inanimate objects on sneezing, coughing and talking. When the person harbouring the virus after wiping the face, touches on the buttons of credit/debit card machines, lift control panel, petrol filling nozzle handles, and handles of supermarket baskets/trollies the virus are transferred to the surface. These are the common fomites touched by hundreds of people every day. On the steel and plastics, the virus can survive as long as 72 hours. But on the card board it is reduced to 24 hours and on copper surfaces it survives only a few minutes! A study from China found that the virus can travel on the soles of shoes and therefore it can be dormant on the pavement. We have seen in China and other Far East countries, disinfectant tankers sprinkling disinfectants on the road and pavements. But the aerosol of these disinfectants or bleach in sight can irritate the eyes, lungs and worsen symptoms in people who have respiratory diseases. The chance of transmission through inanimate surfaces are not much, compared to droplets and aerosol transmission from an infected person.
It is a known fact that the viral load is an important factor in the development of a serious or mild illness. Remember the young Chinese doctor, Hu Weifeng who raised the alarm over Covid-19, died of Covid-19 because of his exposure to huge volume of coronavirus in the ward. Coronavirus is a new virus and still we have not yet fully understood on what all methods it is transmitted, how it cannot survive as long on copper surface as on steel. We do not know whether the virus still lurks in the tissues of convalescent patients, like that of Herpes Zoster virus or wholly eradicated. Research also should be directed to the reason for long covid.
Dr.C.J.George
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