Poser on booster shots

ON Aug 18, public health and medical experts from the United States Department of Health and Human Services (HHS) announced the US administration’s plan to give Covid-19 booster shots to the American people (https://bit.ly/3knwhR1).

In a statement released by the Food and Drug Administration (FDA), the experts stated: “We are prepared to offer booster shots for all Americans beginning the week of Sept 20 and starting eight months after an individual’s second dose.”

Their decision was based on the analysis of available data which “make very clear that protection against SARS-CoV-2 infection begins to decrease over time following the initial doses of vaccination, and in association with the dominance of the Delta variant, we are starting to see evidence of reduced protection against mild and moderate disease.”

However, they did acknowledge that the “Covid-19 vaccines authorised in the United States continue to be remarkably effective in reducing risk of severe disease, hospitalisation, and death, even against the widely circulating Delta variant.”

In the time of a pandemic, we must balance between individual and population risk. The role of vaccination in a pandemic is to ensure that as many people get vaccinated as soon as possible. Unless we reach a vaccine coverage that will be able to offer some form of herd immunity, giving booster shots for individuals to have stronger protection may not be sufficient.

We have seen how SARS-CoV-2 has evolved or mutated over the past 18 months. Vaccines that were developed based on the original strain of the virus were earlier found to be effective in limiting transmission and preventing people from getting sick.

With the uncontrolled spread of the virus and millions of people getting infected, SARS-CoV-2 had a chance to mutate, and the most effective variants have survived and continue to spread.

Reports from many countries, including Malaysia, say that individuals who are fully vaccinated were still infected with the Delta variant and the viral load is the same as non-vaccinated people. The reports also show that fully vaccinated people suffer less severe symptoms of the disease and are less likely to be hospitalised or die from it. This is good news, which indicates that the current vaccine regime is still effective against the new variants.

The world, especially developed nations, should therefore not lose focus on the primary vaccination campaign. In its “Interim statement on Covid-19 vaccine booster doses” dated Aug 10, 2021, the World Health Organisation has reiterated that the focus should remain on increasing global vaccination coverage (https://bit.ly/3z2nJ7V).

According to the most current vaccination data from WHO, there are still 77 countries with less than 10% of their population who have been fully vaccinated. Another 33 countries have less than one percent of their population fully vaccinated.

As such, the statement “No one is safe until everyone is safe” is still relevant.

There should be no attempt to divert the vaccination drive for booster doses when there are still many people in the developing world who have yet to receive Covid-19 vaccines. If we do not vaccinate the world, the virus will continue to mutate and it will be very difficult for us to move beyond the pandemic.

Besides, WHO has also stated that to date, the evidence remains limited and inconclusive for any widespread need for booster doses following the primary vaccination series.

DR VICTOR HOE

Professor of Occupational and Public Health

Universiti Malaya