Shifting Trend- A sign on an impending COVID-19 third wave in India
In the column, the author dwells on the issues of rising R values in India, potential third COVID-19 wave, and the current scenario of Kids' vaccines and school re-opening.
Updated on 4 Sep 2021, 7:43 pm
Rising R Values
There is a worrying trend in the COVID situation in India, of late. The R number in the last week of August shot up to 1.17, as reported by scientists working at the Institute of Mathematical Sciences (IMS), Chennai. As a comparison, let's look at the R-value just a week earlier. It was just 0.89 during Aug. 14-17, 2021. Dr Sitabhra Sinha, lead author of the latest report, says that "Not only is it greater than one, it is much higher than the last time there was a scare of a third wave (it was 1.03 at that time)."
Why is R number so important. It signifies the number of people an infected person can transmit the disease (in this case COVID-19) to, on an average. A value of 1 means that an infected person, on an average, is transmitting the disease to 1 uninfected individual. If R dips below 1, the pandemic will gradually taper off. However, if R is greater than 1, the number of infected people would increasing in each round and the disease will be in the epidemic phase (that is, surging ahead fast). In that case, the outbreak may go out of control and there may be a new wave of the pandemic.
Let's say the R number is 1.1. This roughly means 100 infected persons could transmit the disease to 110 people (in the first round), with correspondingly higher numbers of infected persons in further rounds. The R-value denotes how fast an infection is spreading, a slight rise in the value may indicate an imminent upward trend in the wave again! India's R number rise may be attributed to surge in Covid-19 cases in some states. As per data released by IMS, R-value of Kerala is 1.33 (HT, Sep 4, 2021). Some other states with high R numbers are: Mizoram (1.36), J & K (1.25), Andhra Pradesh (1.09) and Maharashtra (1.06).
During the peak of the 2nd wave (Mar-May, 2021), the R-value was 1.37. During May 15-June 26, the value declined to 0.78. But it gradually started rising: it was 0.88 (June 20-July 7), 0.95 (July 3-22), 0.96 (July 24-27). The threshold value of 1 was crossed for the first time after the 2nd wave during July 27-31 (R-value, 1.03). The R number then started waning again: 0.92 (Aug. 6-9), then rose again: 0.99 (Aug. 12-14). The number dipped to 0.89 (Aug. 14-17) but abruptly jumped to 1.17 in the last week of August 2021.
Although we may not be fully certain, this shifting trend may be a sign on an impending third wave of COVID-19 in India!
Possible Third Wave
The possible imminence of a third wave is the likely outcome of several factors: rise of new variants, adherence to Covid-appropriate behaviour (CAB), level of susceptible population, rate of vaccinations, and rigour of pandemic control authorities. Ironically, except the first one, all other factors are partly or fully under our control. Still, we have failed to contain the pandemic even after more than one and half years. Possibly, human behaviour is more whimsical than that of the viruses!
Let's reflect on some of these factors. First, the emergence of new variants. The WHO has recently dubbed a new coronavirus variant, Mu variant, as a 'variant of concern (VOI)." It's technically designated as B.1.621. It was first detected in Columbia in January 2021 and has since spread to about 39 countries. It has acquired mutations that enable it to partly escape the immune response triggered by the vaccines. WHO has dubbed it as a VOI. There are now 5 variants of interest now: Eta, Iota, Kappa, Lambda and Mu. If Mu acquires more changes that make it more harmful, it may become a 'variant of concern (VOC)." At present, there are 4 VOC: alpha (B.1.1.7), beta (B.1.351), gamma (P.1) and delta (B.1.617.2). The Mu variant now accounts for 39% of new COVID cases in Columbia; luckily, there are as yet no recorded Mu cases in India.
The delta variant has given rise to 13 sub-lineages: AY.1-AY.12 and AY.3.1. AY.1 is what is often referred to as Delta Plus (technically, B.1.617.2.1). Recently, one of these sub-lineages AY.12 has been found in some states in India including Uttarakhand (News 18, Aug. 31, 2021). Whether this or other sub-lineages of the Delta variant will cause a third wave in India remains to be seen.
Another variant called C.1.2 has been found in South Africa and some other countries. Preliminary reports claim that it could be more infectious and may evade the protection provided by vaccines. It has not been categorized yet as either a VOI or VOC. It was first dtected in South Africa in May 2021 has since spread to China, DRC, Mauritius, England, New Zealand, Portugal, and Switzerland etc. So far, it has not been found in India. It possibly has the fastest mutation rates among the variants (41.8 mutations per year). This strain could be more transmissible and has the potential to escape immune protection (IT, Aug. 30, 2021).
Another concerning strain called the Epsilon variant has been detected in Pakistan (www.india.com/; last accessed, Sep. 4, 2021). The most worrisome aspect is that this strain is possibly resistant to all the available vaccines. This varaint was first detected in California in 2020 and has now landed in our backyard! This variant is technically called CAL.20C. It has been found in 34 nations besides the US. It's possibly as transmissible as the Delta variant. It triggered the 4th Covid wave in Pakistan.
This or a sub-lineage of Delta could possibly trigger a third wave in India. But the severity or timing of the wave is subject to how strictly we follow the CAB and how soon we scale up double jabbing the majority of the population in India and Manipur. Let's remember that the virus needs a susceptible host, irrespective of the social status of the host. Therefore, we must strictly avoid crowding of any kind: religious, cultural, recreational, or political etc. We cannot allow certain kinds of crowding while banning other types. We got two powerful weapons against the variants: masks and vaccines. Let's note that, amidst the raging variants, 1 dose isn't effective; so, the target has to be, to fully vaccinate (double jabbing) 70-80% of the population as soon as possible.
According to Dr Manindra Agrawal, IIT, Kanpur, there are various possible scenarios of the third wave. If no new virulent strain emerges, the situation may not change much (Status Quo). However, if a new variant emerges, which is 50% more infectious, then a third wave would hit India which may peak between October and November 2021 (Mint, Aug. 30, 2021). In this scenario, there could be about 100,000 new cases per day in India in the 3rd wave (much less than that of 2nd wave). Please note that there are various other mathematical models that predict much more sevre third waves: some ven projecting over 6 lakh new cases per day in India!
As more and more adults get vaccinated, the virus will find that the majority of susceptible hosts would be children. However, as children have less levels of ACE-2 receptors in their bodies, majority of infected kids would be asymptomatic or have mild diseases. But children with co-morbidities could land up in hospitals; a significant percentage might die or those who recover may suffer from long COVID syndromes such as MIS-C.
As several states are re-opening schools after more than one and half years, we need to look at the situation of vaccines for kids in India.
ZyCov-D, world's first DNA vaccine has been recently granted EUA for people of age 12 and above. It may become available before the end of September, if all things work out as planned. SII is also conducting phase 2/3 clinical trials for its Covovax vaccine on children aged 2-17.
Results of the trials for pediatric Covaxin may be out by September; and we may soon see this vaccine in pediatric vaccination centres/wards. BIOLOGICAL E vaccine for kids aged 5-18 has been recently granted approval for phase 2/3 trails. Other pediatric vaccines that could be on the pipeline include Gennova and Johnson and Johnson vaccines.
Re-opening of Schools
In the interest of academic growth of children, it's definitely desirable to re-open the schools. But, as what's on stake is not very clear, we must search deep in our minds and souls for the answer to the question to re-opening.
Two schools of thought may contend here. One is to say, let's postpone reopening the schools till all the children of various grades are fully vaccinated. A UK panel has recently recommended that there's no need to vaccine young people aged 12-15. The consensus seems to be for vaccinating children age 12 and above with co-morbid conditions such as liver, kidney, and heart complications etc., on priority basis.
The 2nd school of thought is: open schools with certain preconditions. These are: vaccinate all school teachers, support staff, drivers of school buses/vans etc. Improve the available space in classrooms and ventilation conditions. Assure good healthcare support facilities, in case any student falls school after re-opening. Immediately close down the schools if there is a spurt in cases (there has been a scary surge in Covid cases in kids recently in Southern States of USA).
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:
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.
Debananda S Ningthoujam
The author teaches and studies microbial biochemistry and biotechnology at Manipur University