Viruses, variants, and vaccines

Almost one year has quickly passed since the government imposed a general lockdown to contain the novel coronavirus outbreak that was first reported in Wuhan, China. In our country alone, the virus has infected over half a million people and killed more than 12,000. And these are only the official figures. The actual numbers are likely much higher.

We’ve been lucky in a sense, compared to other countries like the United States, India, Brazil, and much of Europe, which have seen deaths soar to the hundreds of thousands. Globally, COVID-19 has killed more than 2.6 million. And, there are still some 25 million active cases all over the world.

Seeing a steady fall in new infections and deaths daily in the last four months, government officials have felt more confident in recommending a relaxation of quarantine rules and travel restrictions so as to create breathing space for expanded economic activity. But, a surge in new cases in just the past few days has put a damper on these plans.

Last Friday, the Department of Health reported 3,045 new cases — the second highest figure for one day since Oct. 16 last year, when 3,139 new infections were recorded. If this alarming upward trend continues, we may be seeing the real “second wave” everyone was talking about last year. What might be even more worrisome is that variants of the original virus could be causing this spike.

Mutations are to be expected. For, if a virus may be said to have any aim at all, it is to survive and multiply to the extent that it can. To do so, it has to keep on adapting to new conditions. It has to mutate to survive. By preventing viruses from invading healthy cells and using these to multiply, vaccines interrupt the replication process. The infection, even if not fully blocked, does not progress into disease. The virus is stopped from multiplying.

The more significant the variations are, the harder it is for the early vaccines to bar the virus. Despite the inoculation, the human body’s defenses may fail to recognize and stop the mutant from finding a home in healthy cells. This is probably the reason why variants are often seen as being more transmissible and more capable of producing a higher viral load.

Of the coronavirus variants that have appeared this past year, three have been identified as particularly troublesome. These are: The B.1.1.7 (also known as the UK variant), the B.1.351 (the South African variant), and the P.1 (the Brazilian variant).

The UK strain, with a total of 118 cases, appears to be the most widespread variant in the Philippines at this point. That’s still small, but there could be more out there, experts warn. The usual swab test result does not show which variant an infected person has. Samples from positive swabs have to be sent to the Philippine Genome Center in UP for genomic sequencing.

The South African variant, on the other hand, has thus far been spotted in 52 samples submitted to the PGC for sequencing. Of these, 51 are regarded as still “active” cases, while one has been classified as “recovered.” As earlier noted, these numbers, still small, may not be indicative of the prevalence of the South African coronavirus strain, since not all swab samples are subjected to genomic sequencing.

There is a third variant that is causing the greatest concern—the P.1 variant or “Manaus strain” first noted in the city of Manaus in Brazil’s Amazonian state. This variant has been observed to carry 10 times the viral load of the original coronavirus. It is now reported to be present in 17 out of 27 states in Brazil. This South American nation has recorded 9.5 million coronavirus cases (and 232,431 deaths)—the world’s third biggest number of cases, after the United States and India.

So far, there has been no report of the Brazilian strain in the Philippines. But, it’s probably just a matter of time before it reaches our shores. Let’s pray it doesn’t. According to a March 2 report of Telesur news agency: “Scientists from the University of Sao Paulo and the University of Campinas reported that the Brazilian strain called P.1 could escape the antibodies generated by the Coronavac vaccine.” Though not yet peer-reviewed, the preliminary study has been reported in The Lancet.

In light of these developments, it’s almost certain that the first vaccines that were rolled out before the appearance of these three variants may need to be supplemented by a later third dose to boost immunity against COVID-19. I believe this was the context in which the US-based Dominican priest and molecular biologist Fr. Nicanor Austriaco issued a warning against post-vaccination complacency. It’s unfortunate that he appeared to single out the AstraZeneca vaccine, suggesting that without a subsequent booster shot, it might be “ineffective” against the South African variant.

This observation holds true for all the other vaccines: They may not offer adequate protection against all possible variants that may emerge. Still, some level of protection is better than none. In a later interview, Father Austriaco clarified his earlier statement and emphatically recommended that we take whichever authorized vaccine is offered to us.

To be fair, it was AstraZeneca itself that first reported the limitations of its vaccine against the B.1.351 variant, citing the results of a small study. As a scientist, Father Austriaco must have felt a duty to report it. Alas, ordinary people do not always draw the same conclusions as the experts from the scientific information they hear or read. Instead of inducing a guarded optimism, an explosion of information may ironically reinforce a latent vaccine skepticism.

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