A new subvariant (sublineage) of the Delta variant has been reported in several countries including UK, Russia, China, Denmark and Germany. It is called AY.4.2 mutant and is a sublineage of the Delta variant that triggered an alarming surge in COVID cases across the world. This subvariant was first identified in July and it currently accounts for about 10% of new cases in the UK. The alarming thing is that, unlike UK, the genomic surveillance is not very robust in most other countries including USA and India. In US, which is behind UK in genomic tracking, only less than 1% of new cases are attributed to this new sublineage.
This subvariant has not yet been categorized as either as a variant of concern (VoC) or a variant of interest (VoI); UK authorities have dubbed it as variant under investigation (VUI). AY.4.2 is also sometimes called a 'Delta Plus' variant or VUI-21OCT-01. It has 3 concerning mutations: A1711V, Y145H, and A222V. A1711V affects the SARS-CoV-2's Nsp3 protein, which plays important roles in viral replication. Y145H and A222V mutations affect the coronavirus' spike protein, that plays crucial roles in infecting human cells (TOI, Oct. 27, 2021; IE, Oct. 27, 2021).
The sublineage has also found its way into India; so far, 17 cases have been reported from 6 states in India (Andhra Pradesh, 7; Kerala, 4; Karnataka & Telangana, 2 each; J & K and Maharashtra, 1 each) (India TV News, Oct. 28, 2021). But, as India's surveillance isn't as robust as that of UK, many cases may possibly remain hidden in the background.
It's still not clear if the new sublineage can spread faster, cause more serious disease or evade immune protection. However, some estimates claim that the new variant is at least 10-15% more transmissible than the original Delta variant. With the sudden spurt in cases and deaths in UK, Russia and China, the message is clear: the pandemic is not yet over and we can't afford to be complacent. More studies will reveal if the new sublineage could cause more sever disease or partially evade vaccine-induced immunity.
Possible Third Wave
Experts opine that the third wave has already began in the UK and Russia, possibly due to AY.4.2 or other variants (Business Standard, Oct. 29, 2021). However, it's too early to definitively say that a third wave may be triggered in India by AY.4.2 or other variants. However, with the upcoming festival seasons, elections, and easing of restrictions as well as low vaccinations (nearly 70% of Indian population is yet to receive a 2nd dose), we must be wary and take good care of Covid-appropriate behaviour (CAB) for many more months to come.
It's also important to remember that vaccine-induced immunity wanes over time and India's children (about 40 crores) are yet to be vaccinated. Meanwhile, the heartening news is that India is planning to launch a Polio campaign-like approach to Covid vaccination to ensure universal vaccine coverage within a stipulated time. Let's remember that large unvaccinated population gives an opportunity for new variants to emerge.
That vaccination is very important is also indicated by a new study which found that people who were unvaccinated and had a prior infection were 5 times more likely to catch Covid-19 as compared with those who have been vaccinated (Business Standard, Oct. 30, 2021). This view is also reinforced by the number of cases in Eastern Europe which has now reached 20 million. Countries in this region have much lower vaccination rates compared to those in Western Europe. Meanwhile, the global COVID-19 deaths have now touched the 5 million mark, possibly due to the global spread of the Delta variant. It took about a year to hit the 2.5 million, but the next 2.5 million deaths were recorded in less than 8 months (Reuters, Oct. 3, 2021). Another alarming report is that over 50% of recent deaths in Kerala occurred among those who have been vaccinated (ONmanorama, Oct. 12, 2021). This may possibly be due to vaccine-induced immunity declining in course of time.
If a fresh wave of infections emerge in India, both the health authorities and the common people have to equally share the blame!
Children's COVID Vaccines
The US FDA has recently approved the pediatric Pfizer Covid vaccine for emergency use in children between the ages of 5 and 11 (FDA News Release, Oct. 29, 2021). The vaccine was found to be 90.7% effective in preventing infections and had no serious side effects. However, logistic arrangements and preparations would face more challenges compared with the same for adults. In the US, cases in children of age 5-11 account for nearly 39% of cases in individuals younger than 18 years.
Another challenge to overcome is trypanophobia-fear of needles-which most children intrinsically have, which would greatly hamper the pace of vaccinations among kids.
India has already approved 2 vaccines for kids: ZyCoV-D and Covaxin, but they haven't been rolled out yet.
New COVID Drugs
UK scientists have found a new treatment for curing Covid-19. The drug is called benfooxythiamine, which is an inhibitor of the pentose phosphate pathway (PPP) (ANI, Oct. 29, 2021). Cells infected with SARS-CoV-2 can only produce coronavirus progeny when their metabolic PPP is activated. Benfooxythiamine, by inhibiting this pathway, suppress coronavirus replication and infected cells cannot produce new coronavirus particles. This research was jointly conducted by University of Kent, UK and Goethe University, Frankfurt am Main. This new drug also increased the antiviral activity of 2-deoxy-D-glucose. Another advantage is that, as the new drug has a novel antiviral mechanism, viruses resistant to other antiviral drugs such as remdesivir and molnupiravir, may be susceptible to benfooxythiamine. The study has been published in the premier scientific journal, Metabolite. There are many other drugs in the pipeline, and we can only hope that with the approval of such drugs, we may put COVID-19 in check in the early part of 2022!
Possible Measures for Manipur
We need to assume that there may be a third wave in Manipur too. Even if that may turn out to be a wrong anticipation, it's better to err on the side of caution. Accordingly, we must initiate measures to squarely face a possible third wave in our state. These may include:
Preparations for administering vaccines to kids in Manipur & booster shots to high-risk people (elderly, healthcare workers and people with weak immune systems).
Conducting immediate seroprevalence studies to understand what percent of population in Manipur and in its different districts are still susceptible to the coronavirus.
Speeding up vaccinations in a big way; aggressive vaccinations with monthly targets to cover all eligible population with first doses in the next few weeks (4-6 weeks); and targeted vaccinations of all adult population with second doses in the next 2-3 months.
Regular & repeated COVID testing in hotspots.
Enhancing the ratio of RT-PCT to Rapid Antigen Testing (RAT).
Weekly "awareness messaging" about the pandemic to the public by a designated healthcare official.
Genomic sequencing of a subset of positive cases and surveillance of the variants including the delta variant: which COVID strains are there in Manipur, where are they, and where are they moving towards; and whether any new variants are emerging.
Contact tracing and government-monitored isolation of positive cases, wherever feasible.
Boosting up healthcare provisions such as medical oxygen plants, tankers and cylinders; steroids, antifungal drugs, oxygen concentrators, ventilators, oximeters, masks, PPEs, sanitizers etc.
Strengthening of healthcare infrastructure such as construction of new COVID hospitals.
Provision of more COVID care centres (CCCs), more Covid beds and ICUs in existing hospitals
Constitution of a special taskforce for the third wave; a separate taskforce for pediatric COVID is also highly recommended.
Special provisions for kids such as pediatric hospitals, wards, and ICUs, pediatric oximeters, concentrators, and ventilators and strengthening of staff such as pediatricians and pediatric nurses and paramedical workers etc.
First published:31 Oct 2021, 6:48 am
third wavecovid variantsChildren's COVID VaccinesCOVID Drugs
Debananda S Ningthoujam
The author teaches and studies microbial biochemistry and biotechnology at Manipur University