COVID-19 – renewed threat

There has been a dramatic lowering, in the past month, in the number of infections and deaths due to COVID-19 in our country, with 75 new infections reported on average each day. That is just 26% of the peak — the highest daily average reported on September 17, which was also our deadliest month. Yesterday, there were only 2 fatalities and 50 new infections against a total of 985 deaths and 37,663 cases since March 2020.

With more than half of the population vaccinated two weeks ago, and most deaths occurring in the unvaccinated, partially unvaccinated, or vaccinated with waned immunity populace, the Ministry of Health (MoH) had decided to introduce booster shots for those over 50, and also those with co-morbid conditions such as diabetes. A vaccination programme had also been rolled out for school-age children, but, as with the old age cohorts, there has been a worrying degree of “vaccine hesitancy” that has led to some regions of the country – such as Reg 6 – having worrying higher rates of infection. Another nettlesome statistic was the revelation yesterday that of 38 persons in the ICU at the Infectious Disease Hospital, 23 were pregnant women.

However, with the overall drop in deaths and infections, there are some who believe that we may have entered the “endemic” stage of the COVID-19 scourge. As opposed to an “epidemic”, when infections and deaths are rising exponentially, the endemic stage means that daily numbers of COVID cases had risen to a peak (here in September) and declined systematically, until a steady state with low numbers (endemic prevalence) is reached.

Why should COVID epidemic transition to the endemic phase? At any point in time, the number, proportion and distribution of non-immune versus immune people determines the transmission speed R. When the pool of the susceptible is large, R rises above 1, and when the pool of the immune is large, R falls below 1. The end of the epidemic denotes that the herd immunity threshold (HIT) applicable to the particular variant has been reached. But does this mean that the pandemic is over in Guyana?

Certainly not. Next door, in Trinidad, after 31 persons died last Thursday – their highest to date – they earned the dubious honour of becoming #1 in the entire world in the number of deaths per million populace 22.09. In the meantime, the developed European countries with vast numbers of vaccines are also topping the charts in deaths and infections from COVID-19. Even though the Opposition anti-vaxxers have toned down their strident campaign, we certainly cannot become complacent.

Especially when a new and much more virulent variant the ‘B.1.1.529’, called “Omicron”, has appeared in South Africa and already found in Botswana and Hong Kong. Several countries, including the US, UK, Israel, Italy and Singapore, have already moved to restrict travel from South Africa and other countries in the region. According to South African health officials, the ‘B.1.1.529’ variant has many more mutations than scientists expected, especially after a severe third wave, which was driven by the Delta variant. Many of the mutations are of concern for immune evasion and transmissibility. “Omicron” carries a high number of mutations in its spike protein, which plays a key role in the virus’s entry into cells in the human body. The B.1.1.529 variant has 50 mutations overall, including more than 30 on the spike protein alone, which is the target of most current COVID vaccines.

The high number of mutations suggests that all of the present vaccines which were designed to counter the original Chinese Wuhan strain might not be as effective. The WHO is presently investigating the strain, and is expected to issue a statement soon. But we have to assume that, as with the more virulent Delta strain, which is still wreaking havoc in Europe, “Omicron” will force the entire world to start a new wave of vaccine development, and rolling them out to a pandemic-weary populace.