25 April, 2024

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Overview Of Covid-19, Infodemics & Development Of Vaccine

By Meththananda De Abrew –

Dr. Meththananda De Abrew

World Health Organisation (WHO)was informed of a cluster of strange pneumonia by Wuhan Municipal Health Commission, China on 31.12.2019.

This disease was caused by a new strain of Corona virus with rapid deterioration of patients requiring level 3 critical care support. It is related to a group of  respiratory  viruses. Some of these group of viruses presented as SARS, severe acute respiratory  syndrome and MERS, middle east respiratory syndrome. First report of corona virus illness dates back to December 2019. Initial impression was that virus originated from Live animal market in Wuhan by a process called zoonosis, where animal to human transmission occur. This theory has now been disputed.

SARS was identified in Guangdang, China in 2002 and there were 8000 cases worldwide. It spread to 26 countries and the countries affected include Toronto in Canada, Hongkong, Taiwann Singapore and Vietnam. Severity of disease was variable and range from mild upper respiratory tract infection to pneumonitis requiring oxygen support or ventilation. Symptoms of SARS were fever, headache, malaise, myalgia, diarrhoea and rigors(shakes). There were numerous attempts at developing a vaccine by WHO and many other affected countries but none was successful. 

First outbreak of MERS (Middle East Respiratory Syndrome) was reported in Saudi Arabia in September 2012. This virus is also belonged to Corona Virus family (Cov 1) and symptoms were similar to SARS and worst affected patients needing supplementary Oxygen Therapy or Ventilation. First epidemic outside Arabian Penisula reported in Republic of Korea thought to be related to travellers returning from Middle Eastern countries. Developing a vaccine was again proved to be unsuccessful and there is no  treatment.

World Health Organisation(WHO) decided  in mid February that new Corona virus disease should be called Covid-19 to avoid stigmata to country, region, area and individual group of people. Not withstanding some politician continued to call it corona virus or otherwise. Covid-19 is known to present with multitude of symptoms similar to symptoms of SARS or MERS. However triad of symptoms, high fever Temperature above 38 C, continuous dry cough and shortness of breath should lead to suspicion of Covid-19. In middle of January 2020, few significant events were reported. First case outside China was reported and second case was reported in Japana followed by first European case a few days later in France. More importantly protocol  for RT-PCR assay was published by WHO.

There were concern about human to human transmission, first mentioned by a professor of Microbiology from Hongkong and on 19 January WHO confirmed

human to human transmission, admitted by Chinese authorities a few days later.

In view of this finding , risk s of exposure to covid 19 by front line healthcare workers in community, homecare and healthcare setting was appraised and use of face coverings was recommended by the end of January. On 30 January major  incident of Publichealth Emergency of International Concern (PHEIC)was declared by WHO. Main  modes of spread is by aerosol, droplets and touch. Initially it was thought that virus could survive for up to 8 hours in air and surfaces now scientists believe virus can survive up to 3 days on metal and plastic surfaces. On 11 March WHO declared Covid 19 is a pandemic. President Barrack Obama warned Americans and the world to prepare for viral Pandemic way back in 2014, wisdom rather than intelligence. Niether Americans nor the world heeded to his warning.   

Asymptomatic carriers shedding viruses was recognised at UN crisis meeting in first week of April. While WHO were using all tools at their disposal to manage publichealth emergency unfolded, shortsighted  actions during electioneering and other political and sporting events in major developed  economies as well as developing countries, led super spread of virus. WHO-China joint mission stressed that to reduce Covid-19 illness and death, near-term readiness planning must embrace the large scale implementation of high –quality, non-pharmaceutical public health measures. These include case detection and isolation, contract tracing, monitoring/quarantining and community engagement. With increasing number of new cases and death rates, acute hospitals in health setting in major economies finding difficult to cope, lockdown in major economies became inevitable. To protect frontline workers in health settings  and recognising there was a shortage of personal protective equipments (PPE), WHO issued guidelines for use of PPEs and issued a call to increase manufacturing PPEs by 40% to meet the global demand in 1st week of  April.

For the first time Total number of Covid 19 cases  worldwide exceeded 100,000 on 7 of March and at the time of writing total number of cases worldwide exceeded 56 million and deaths exceeded 1.3 millions. A few days later WHO declared Europe was the epicentre of Covid-19 with more cases and deaths than the rest of the world combined apart from people republic of China. For some inapparent reason incidence  and death in South East Asia, namely Thaiwan, Singapore, South Korea, Thailand, Hongkong and Vietnam were far less than countries in temperate zones. Initial theory of high ambient temperature in south East Asian counties relevant to low prevalence, was later debunked.

Economic impact  of lockdown on businesses and employment was massive and some small businesses were heading for bankruptcy. Daily wage earners and people with short term employment contracts were in serious difficulties. There were relief measures available in various countries. British Government introduced furlough scheme where 80% of the salary were paid by the treasury. Scheme were to be terminated by end of October but due to introduction of fixed 2nd lockdown, scheme is to continue to the new year. In United States millions of people applied for unemployment and social benefits. Global Humanitarian Response plan for $6.7 billion was launched by United Nations for low and middle income countries, on 7 May.

Covid 19 has no boundries and several key figures in British Government, European Union, Brazil and even President Of United States contracted it, latter part of Election Campaign. World was crying out for an antiviral drug and vaccine. Mis and disinformation were ramphant in social media. Astonishingly. There was guidelines written for treatment of Covid-19 on the basis of rather small cohort of 19 patients, recommending use of hydroxychloroquine and azithromycin. This was reaffirmed by another academic claimed to be professor of pharmacology. Some people who owned You tube channels wrote their own unscientific views and herbal treatment for a virus spreading rapidly with daily deaths of tens of thousands. 

To counteract infodemics, WHO launched health alert on Whatsapp in multiple languages with uses around the globe giving instant, accurate information about Covid-19. Realising the harmful effects of misinformation to the public and communities, they also launched Facebook Messenger CHATBOT version of its health Alert platform. Infodemiology is the science of managing overburdance  of

Information, some accurate and some not, occurring during epidemics.

Infodemics was of unimaginable scale and need for randamised control trials could not be overemphasised. On 18 March WHO announced Solidarity trial. On the same time line two other clinical trials namely Recovery trial and DisCoVeRy trial were launched.

Purpose of these trial are to accelerate the process of design and conduct, rapid worldwide comparison of unproved treatment and to overcome risk of multiple small trials not generating the strong evidence needed to determine the relative effectiveness of potential treatment. 

The following existing drugs are being tested on, in hospitalised patients who are sick or requiring oxygen therapy, in these randamised trials but with variation in different arms.

1. Low dose dexamethasone

2. Hydroxychloroquine

3. Azithromycin

4. Tocilizumab (anti-inflammatory drug)

5. REGN-Cov 2 (monoclonal antibody)

6. Convalecent plasma

7. Aspirin

8. Lopinovir/retinovir

There were no recruitment problems in to these trials but of note in South East Asia, only Thailand enrolled in the solidarity trial. Other countries participating in multicentre solidarity trial are Argentina, Bahrain, Canada, France, Iran, Norway, South Africa, Spain and Switzerland. Interim results of recovery trial  was reported in mid June. Low dose dexamethasone reduced deaths by a third in ventilated patients and by a fifth among patients receiving oxygen therapy only. Much acclaimed Hydroxychloroquine had no effect on Covid-19 and discontinued from Solidarity trial. Lopinavir-Ritonovir arm revealed no clinical benefit and discontinued from trials by End of June. On the other hand Remdeseavir, antiviral drugs effective against Ebola was shown to shorten duration of illness by 4 days. It is a nucleotide analogue which inhibit  enzyme, RNA polymerase in viral particles. As readers were alluded to  most of these drugs were given to a political leader of Major democracy, irrespective of clinical evidence. We are in to the 11th month since Covid-19 invaded our Planet yet there is no effective antiviral drug despite some Aurvedic physicians and a misguided professor claiming they have the remedy in the form of a herbal elixir, for the disease. If proven no doubt they will be Noble Prize winners but  Noble Prize committee will not accept unscientific statistically unvalidated evidence. Messages coming from gods does not hold water in scientific practice!

Status of Vaccine

Development of a vaccine usually takes years. Currently there are 198 vaccine developers around the globe. There are 6 vaccine developers in collaboration with Pharmaceutical giants and universities, made the headway. They are Pfizer -Biontec, Moderna already reported phase 3 results with 95% efficacy, awaiting approval by regulatory authorities in different countries, FDA in USA and MHRA in UK. Oxford group in association with Astra-Zeneca reported promising Phase 2 results ie Good immunological response in people above 60yrs. Results of Phase 3 trial conducted in UK, America, Brazil and South Africa is expected to be reported soon. Other Key players in the fore front are Jansson, Imperial College and University of Southampton. 

Important feature of these new vaccine is they are not based on attenuated virus but on spike proteins or m-RNA. Hence there should be no fear in contracting the disease following vaccination. Two injections of coronavac made by Sinovac (otherwise known as Beijing Kexing Bioproducts) cost 2000 rmb ($300) at the private Taihe Hospital in the  the Chinese capital. The vaccine still has not passed final stage 3 clinical trial, but is already being offered to the public on a first come first served basis. It is not just the coronaVAc vaccine on offer in China. An unofficial vaccine rollout is gathering pace despite the warning of international public health experts.

COVAX Facility

Rich Western Democracies have ordered millions of doses of vaccine through their Vaccine Task Forces. For instance Britain have ordered 100 million doses from 4 different manufactures. It is important that low income and fragile countries should have fair access to vaccine. COVAX facility is a mechanism designed to guarantee fair and equitable access to vaccines and distribution. Thanks to United Nations and they agreed to release $10.3 billion to fight the virus in low income and fragile countries.

Well into the 11months of this pandemic there appear to be light at the end of the tunnel. Scientists and Vaccinologists have burned midnight oil and worked 7days a week to bring about a successful vaccine. This does not mean public and communities drop their guard and be complacent. All important space, face covering and hand hygiene and vigilance  must be maintained for sometime to come. At the time of writing  one person is dying from Covid 19 every 17second. Mass gathering for political reasons, national celebrations, religious festivals, and sporting events  must be avoided. By and large lots of countries use invaluable services of the armed forces to control the pandemic. However they can not lead the process and stratergies and modelling got to be developed by the Epidemiologist, virologists and scientists. It remains to be seen  if life will ever be returned to what we used to knew and enjoy.

*Author: Meththananda De Abrew LRCPS FRCS(Gen. Surg)

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Latest comment

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    0

    Thanks, Dr Meththananda De Abrew,
    .
    I’m glad to see people like you writing sense. I don’t have sufficient knowledge to evaluate the progress being made to find a cure, but I fell reassured by the fact that there are persons with your learning following what’s happening and keeping us informed.
    .
    Let me hope that a few other members of the public also keep abreast of what is happening at the frontiers.

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