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Living with the Pandemic

Roundup Wednesday 29/December/2021 11:19 AM
By: Times News Service
Living with the Pandemic
Dr. Dilip Abdul Khadar

Where we stand today


Almost 2 years into the pandemic, mankind has never been blessed more. We could for the first time since the beginning of this once-in-a-century pandemic that has altered our lives beyond recognition managed to come up with the first vaccine for COVID-19 in less than a year. This will go down in history as one of science and medical research's greatest achievements, perhaps the most impressive. We currently have about 8 peer reviewed vaccines which can give reasonable protection against the severe form of COVID infection. We have two novel oral antivirals which is active against all variants assessed.

Two things that should be clearly understood are that no vaccine will make a PCR test turn positive and vaccines against contagious respiratory viruses, like Flu and now COVID, are supposed to keep people out of hospitals and away from ventilators. This is their historical barometer of success. They are not intended to prevent a positive test.

We live at a time where >65% of the world has encountered SARS CoV-2 antigens either through infection or vaccination. We have crossed more than the halfway of the pandemic according to renowned epidemiologists and Infectious diseases specialists worldwide.
By now we know the only way to win against this pandemic and its omicron variant is through a triple vaccine mandate, mask mandate and ensuring COVID appropriate behavior always as responsible citizens. We as citizens should get vaccinated, wear masks, avoid overcrowded closed spaces as the spread of this viral infection is by droplets and aerosols which can be breathed in and even remain suspended in the air for a while after an infected person sneezes or coughs. Prior infection immunity may not protect well against Omicron. We must get vaccinated and boosted.

Omicron and triple vaccine mandate

Omicron is an infectious variant spreading in a non-immune population, with a much shorter incubation time therefore much faster doubling time. It is more contagious than the delta variant. The biggest concern with omicron is that it contains >30 mutations in just the spike protein, the part which helps it enter human cells and the target for vaccines.
7 COVID variants of concern emerged in the past 14 months. Alpha and Delta caused major damage. Others fizzled away. The 4 countries with the highest documented Omicron burden have each exceeded their pandemic record for new cases, and still ascending rapidly which being the major worry.

The data from South Africa and United Kingdom shows that there are higher rates of reinfections and breakthrough infections with this new variant. Many people have got infected for a second and even third time with this variant in SA. The risk of reinfection with the Omicron variant is 5.4 times greater than that of the Delta variant which was 2-4 times more severe than original Wuhan 1.0 strain. As SARSCoV2 evolved to Omicron, transmission and immune escape reached new levels, fortunately, 3 independent studies from top labs, including one in a well-regarded in vivo model, all show reduced lung infectivity vs Delta virus infection.

Omicron’s immune evasiveness across all vaccines and prior Covid infectees, is due to the marked decline in neutralizing antibodies which is seen with all vaccines. Besides studies remarked a waning immunity and reduction in vaccine effectiveness with time after second vaccine dose. Hence a booster shot is now advocated, and a third shot restores it to around 70 %. It is given as early as 3 months for all above 18 years from the second shot to protect well against Omicron variant. Protocols including the administration of booster dose within reduced time frame that keep up with the latest evolving science should be implemented to win over this pandemic.

Though less severe illness related to Omicron are reported from world over for now it doesn't mean our hospitals and healthcare workforce will not be overrun. Despite the “omicron is milder” observation, hospital visitations and admissions for COVID-like illnesses are on record pace in New York City currently. When case numbers go high suddenly, hospitals over burden and there will be shortage of beds and that ultimately leads to increase in mortality numbers especially with this Omicron variant which can double in 1.5 to 2 days.

We have vaccine in abundance thanks to the MOH, so as citizens it is our collective responsibility to make sure the hospitals don’t get overburdened by ensuring triple vaccine mandate, mask mandate and ensuring COVID appropriate behavior everywhere. As a parent or teacher, we can protect our unvaccinated children or student better if we ensure the above. We can further guide our loved ones to vaccinate if they are eligible for the third booster shot as a responsible citizen or help an unaffordable person to take the third shot.

Rapid antigen tests


Even though SARS COV-2 PCR tests remains the gold standard, rapid tests work well with Omicron strain. Omicron is mutated mostly in spike. Rapid tests don't detect spike, they detect nucleocapsid a different part of the virus and they serve a different purpose than PCR tests. Rapid antigen tests are best at catching contagious cases of COVID-19, while the more classic PCR test is more sensitive and can detect genetic signs of the virus even without symptoms.

Currently in the US rapid antigen tests, which can detect if someone is potentially contagious, are in high demand as people prepare for holiday gatherings. Frequency, accessibility and speed are most important aspects of a test for public health and that is the reason it has gained importance.

PCR tests are often described as the gold standard of testing, and they can spot genetic material from the virus within the body several weeks even after a person stop being infectious. Lateral flow tests such as rapid antigen test only detects material from the surface proteins of a virus which are found when someone is infectious. It helps to isolate, quarantine and de-isolate.

Rapid tests given out to people for free in the UK cut hospital stays by a third. Mass lateral flow testing cut the number of people needing hospital treatment for Covid by 32% and relieved significant pressure on the NHS when the measures were piloted last year, a study has shown recently. Lateral flow tests available over the counter are fast becoming a prerequisite prior to meetings and gatherings in many countries.

CDC has now advised before gathering with friends and family, consider using COVID19 self-tests to protect those you care about. Along with vaccines, masks, self-tests can help reduce the spread of COVID-19.

In Germany, you can buy a rapid Covid-19 test at the grocery store for one euro. In Britain, any household can obtain a pack of seven rapid tests every day for free. In Singapore, you can get a free rapid test from a vending machine. Families in Israel receive at-home rapid tests for their children to use before school.

Rapid testing is commonplace in many parts of the world because policymakers recognized early on that the tests could blunt the pandemic by stopping chains of transmission. By letting people know they are infectious, rapid tests are useful even in areas with high vaccination rates and can allow for a safer return to in-person activity.

Rapid SARS-CoV-2 tests for at-home use has been recognized by TIME magazine as one of the top 100 inventions of the year.
 
Child vaccination & School


COVID-19 is also a childhood infection. About 6 million children had been infected in the United States before Omicron wave. Almost 700 children have died from COVID-19 infection in the US till date making SARS COV-2 infection among the top 10 causes of death among US children. No child has died from vaccination. Vaccine associated myocarditis in the young has been rare, relatively mild, and self-limited.

Pfizer has started vaccinating children aged 5-11 years with pediatric dose vials at US. Adult vaccine stock cannot be used for this age group without tricky extra double dilution. It is colour coded with orange caps, to avoid mix-ups with purple-capped vials of adult vaccine.

The FDA examined more children, a total of 3,100 who were vaccinated, in concluding the shots are safe. The younger children experienced similar or fewer reactions -- such as sore arms, fever, or achiness. According to the data for Pfizer vaccination in the US for children aged 5-11 years dated December 20th, more than 6 million children got their first doses and >2.5 million with their 2nd dose and there are no major complications reported.

Hospitalization record for kids has increased in SA, UK and now US with Omicron variant. Even moderate to severe diseases have been reported in children with this new strain.

Children must go to school, meet their friends, actively play, and participate in extracurricular activities for their social and emotional development. This is their life. Cloth masks are not enough. Triple vaccine mandate for all school employees, vaccination for children, mandatory mask mandate using high grade masks and Covid appropriate behavior should be practiced strictly in schools with proper distancing allowing classes like singing and eating lunch practiced out in the open is the current trend among many European countries.

CDC released indoor air guidance for schools during COVID19, which emphasizes: “Opening windows, using portable air cleaners, improving building-wide filtration are ways to increase ventilation in school or childcare program.”

If possible, there must be air filtration with Corsi-Rosenthal boxes and ventilation, at least of MERV-13 standard or even portable HEPA filter for larger classrooms or high-density rooms which is currently practiced as standard of care in many countries. Also important is CO2 sensors. We want CO2 levels as close to fresh air of ~400 and it needs to be monitored. Such practices are common in many European schools and gyms and a spike up over 1000–meaning poor indoor air. Or lastly if the above is not possible, practice common man’s resort- open windows and cross ventilate the room frequently.

Vaccinating all children against COVID-19 could be among the most impactful public health efforts. However, a choice not to get vaccine is not a risk-free choice; rather it is choice to take a different and more serious risk.

The way forward


Vaccinate and get boostered, avoid indoor crowded spaces as much as possible, use KN-95 or N95 masks at high-risk public indoor spaces if no choice, take air travel only, if necessary, use rapid tests before gatherings. If gatherings are unavoidable have them outdoors with a strict mask mandate and distancing. Wash hands before touching your eyes or nose and before meals.

One of the clinical trial results we heard recently is of a “super vaccine” or pan-coronavirus vaccine: a variant proof COVID19 vaccine.
The main approach taken by research labs is to find people called “elite neutralizers” who have had COVID19 or been vaccinated (or both) but have an incredibly rare and unique response. These are people who can make very potent antibodies (called broad neutralizing antibodies; bnAbs) that bind to parts of the virus well beyond the spike protein—parts of the virus that are present in all the coronavirus family, remain unchanged despite mutations, and are hidden. These elite neutralizer people are rare, but there’s basically a treasure chest of protection lying within them. More than 10 scientific groups have found such potent bnAbs. But finding these “elite neutralizers” is half the battle. Then a reverse engineering approach is required to make vaccines that produce the bnAb. After that, the vaccine goes into pre-clinical and clinical trial testing.

A faster approach is like the Spike Ferritin Nanoparticle COVID-19 vaccine developed by researchers at the Walter Reed Army Institute of Research which is the first potential variant-proof, universal, beta-coronavirus vaccine going for clinical trials.

Novel medications
German researchers have found that COVID-19 monoclonal antibody therapies like Regeneron lose most of their effectiveness when exposed in laboratory tests to the Omicron variant of coronavirus, likely reducing treatment options if the new variant prevails. "Due to the substitutions contained within the spike protein of the Omicron variant of concern, it is likely to experience reduced neutralization activity,"

First time sequencing of a virus linked to optimal treatment was found with the monoclonal antibody Sotrovimab, the only monoclonal effective to Omicron-but its availability is limited.

The anti-Covid pill (Paxlovid) is a veritable breakthrough, and was FDA authorized for children as young as 12yrs.It showed an efficacy of 89% in high-risk patients.

It is used for the treatment of mild-to-moderate coronavirus disease in adults and pediatric patients with positive results of direct SARS-CoV-2 testing, and who are at high risk for progression to severe COVID-19, including hospitalization or death. Paxlovid should be initiated as soon as possible after diagnosis of COVID-19 and within five days of symptom onset.

Molnupiravir, another oral antiviral medication for the treatment of Covid-19, has also just been granted EUA by the FDA. It is an influenza drug and duration of treatment is also for 5 days. It showed an efficacy of 50% in high-risk patients.
Then again, the supply of all these drugs is for now limited to the US alone.  

Dr. Dilip Abdul Khadar
Specialist Physician (Intensivist)
Head of Quality & Patient safety
Aster Al Raffah Hospital, Muscat.

(Inspired Source- Articles, opinions, views and write ups by Dr. Eric Topol, Dr. Michael Mina, Dr. Eric Feigl-Ding, Dr. Vincent Rajkumar, Dr. Faheem Younus, Dr. Anthony J Leonardi and other profound Infectious disease specialists and epidemiologists worldwide, Newspaper articles from US & UK, CDC & NHS updates.)