• By Mar-Vic Cagurangan

Will booster shots curb breakthrough cases? Let’s wait and see, doctor says

Updated: Oct 26, 2021

Pobutsky irked by people's 'obsession' with breakthrough cases. It's ‘a bit ridiculous,' she says

More than 6,000 eligible Guam residents have received their booster shots, following federal health authorities’ recommendation.


Does it mean they are completely shielded from breakthrough infections?


Local epidemiologists offer a caveat: do not be overly optimistic.


Dr. Ann Pobutsky is cautious about making a promise that the booster shot offers full protection against Covid-19, which has infected fully vaccinated people as a result of the diminishing efficacy of the initial vaccine shots after six months of administration.


Those who have received their Pfizer, Moderna and Janssen vaccines earlier this year, and later followed up with booster shots “may or may not get infections in the following months,” Pubutsky said at Thursday’s virtual press briefing.


“We don’t know. We are going to watch it. That’s all we can do: watch what happens,” the Department of Public Health and Social Services’ epidemiologist said.



Federal authorities recommended the booster shots, citing evidence that breakthrough infections are becoming more common than expected.


With booster shots being available, “breakthrough infections will need a new definition,” Pobustky said.


Just the same, she is quite hopeful.


“We hope it doesn’t happen,” Pobutsky said, referring to post-booster shot infections. “We think the booster is going to protect people, especially the elderly with chronic conditions. So, all we can say is that it is possible that they might get sick even after getting a booster, although it seems unlikely or it might happen. We are going to watch and observe.”


Guam has more than 82 percent vaccination rate, one of the highest in the United States, Yet, the island also has one of the highest breakthrough rates.


Health authorities have acknowledged that vaccines are not 100 percent effective but maintained that they can reduce the severity of illnesses from the Covid-19 infections.


Pobutsky was miffed by people’s “obsession” with breakthrough cases.


“Ever since we started vaccinating, there has been an obsession with breakthrough cases,” she said. "People continue to ask about breakthrough cases. They want to hear about every single breakthrough case and it is just, to my mind, getting a bit ridiculous.”


Breakthrough infections, she said, were expected to happen with the onset of the delta variant.


“Remember, no vaccine is 100 percent effective. It is the characteristic of delta to have more asymptomatic cases, so we shouldn’t be reporting this,” Pobustky said. “We should be reporting the fatalities and the hospitalizations.”


Pobustsky noted the breakthrough deaths involved people with multiple comorbidities.


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The Centers for Disease Control and Prevention does not count breakthrough cases “unless they involve hospitalized people or fatalities,” she added. “For recording purposes, the CDC only wants to collect data on all serious cases which would suggest that something else is possibly going on.”


Dr. Chima Mbakwem, DPHSS health officer, said Guam’s reporting of breakthrough cases focuses on those who end up in hospitals.


He said CDC has repeatedly notified the public that “there is a chance that those fully vaccinated can be infected but with less severity. They did not say you will not be infected.”


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