Apart from the prick of a needle, getting the Covid-19 vaccine this December was painless for Ki Higa. It was his fourth jab so he knew what to expect.

“It was just easy, everyone was like ‘okay cool, no problem, just fill out this form and you’re good to go,’” Higa said.

This was Higa’s first time getting the Moderna vaccine; his previous three were all Pfizer. But Higa doesn’t qualify for a fourth shot according to the Centers for Disease Control and Prevention guidelines, which so far has only recommended them for immunocompromised people. He’s just worried.

“I have asthma that’s already aggravated by the vog, so I don’t need coronavirus on top of that,” he said.

The situation has evolved since Covid-19 vaccines were first introduced in late 2020 and Hawaii and other states maintained strict protocols for who would get them due to short supplies.

With vaccines now plentiful in the United States, authorities have shifted their focus to encouraging people to get a booster shot, which means a third shot for the Pfizer and Moderna vaccines and a second for Johnson & Johnson.

But while people generally appear more hesitant to get booster shots – only about 35% of Hawaii’s population has received a third shot compared with 75% for the initial doses – some are rushing to get a fourth shot in the hope that it will provide extra protection despite the fact that scientists and officials have not yet recommended that for the general public.

In an “ideal world,” the Department of Health would “like to work toward” having all providers confirm vaccination status before administering shots, but the magnitude of the Covid vaccination campaign makes uniform verification difficult, spokesman Brooks Baehr said.

“We have administered, in the past 13 months, 2.7 million Covid vaccine doses,” Baehr said. “The priority has really been to get shots in arms.”

Many take legitimate routes to a fourth shot, being immunocompromised or joining a vaccine trial. Others, less so.

“So I basically lied and told (the nurse) that that’s my first shot,” said Higa, who has ended up with three vaccination cards. “And I just got another boost.”

The DOH does not publish numbers for unauthorized doses administered in state, and parsing between accurate and inaccurate vaccine records is a complicated process, Baehr said.

“People are going to find ways to cheat the system, we know that,” Baehr said. “If someone fibs to a vaccination provider, the poor provider has no idea that they’re getting bad information that they could pass along to us, which makes things more difficult.”

The Hawaii Immunization Registry is available for physicians, pharmacies, insurers and other medical organizations to submit Covid and other vaccination records. That’s where Hawaii Pacific Health checks recipients’ dosing history, HPH chief quality officer Melinda Ashton said in an email.

However, not all organizations may access patients’ vaccine data on the registry, Baehr said. Vaccines are now widely available at pharmacies and other outlets besides hospitals.

“Before you can go into the system and check on a person’s immunization status, you have to register and go through training,” Baehr said. “Some providers, instead of inputting information themselves into the immunization registry, they have electronic health record vendors that put the information there.”

If the immunization registry detects a possible redundancy, Baehr said, such as booster doses registered under a “Robert and a Rob” with the same birth date, the system will flag the records and an administrator must manually review the entries.

“And indeed, we have actually seen people who have gotten more than the recommended doses,” Baehr said. “But by then the person’s already received their shot.”

As of last summer and before the first booster was approved, the CDC estimated over 1 million Americans had received a third dose outside of government guidelines, ABC News reported. This was almost certainly an undercount, as it did not count people who may have received an extra dose after the one-dose Johnson & Johnson vaccine.

At the time, CDC Director Rochelle Walensky said in a White House press briefing that the government had the capacity to track these cases and that unauthorized doses complicate efforts to evaluate vaccine response.

“It does undermine our ability to monitor safety in these contexts,” Walensky said. “We are asking people to follow our guidance … so we can follow safety signals here as well.”

The Straight And Narrow

Currently, only Americans with moderate or severe immunodeficiencies – which can include recipients of organ transplants or people living with HIV – are eligible to receive a fourth shot per government regulations.

Immunocompromised people were among the first in line when the Covid vaccine rolled out early last year; by August, the CDC recommended these people sign up for a third full dose amid evidence that two doses of the mRNA vaccines were not enough to trigger a sufficient immune response. This additional shot is considered a continuation of the recipient’s “primary series” and not a booster.

In October, the government updated guidelines to encourage people with immunodeficiencies to seek another shot six months after their third dose. The CDC then shortened the interval to five months in a bid to stem a rise in cases of the omicron variant, making many of the estimated 7 million immunocompromised Americans eligible for a fourth dose by January.

Still, some people with immunodeficiencies have reported trouble receiving the fourth jab. East Honolulu resident Linda White said she showed up to her local Walgreens only to be told she needed to wait another month before receiving the Moderna booster.

It took some explaining, but White said she received the booster in the end.

“The good news is I did a lot of research on my own, not on Facebook, but speaking with my doctor, looking at CDC websites,” White said. “But if I hadn’t pushed back, I wouldn’t have been able to get my shot.”

Meanwhile, public health experts and policymakers are still debating whether a fourth shot should be sanctioned for everybody.

Both Pfizer’s and Moderna’s CEOs have said further doses may be needed to combat the highly transmissible omicron and future variants. However, a slew of public health officials have expressed doubts whether endless boosters are the solution as Covid is expected to become endemic.

Israel approved a fourth round of shots for vulnerable residents 18 and up last week, including those who work in high-exposure settings. But the extra dose reportedly didn’t provide much more protection against the omicron variant, according to The New York Times.

Other countries are administering fourth shots to high-risk populations, including Hungary, Denmark, and Chile.

World Health Organization director general Tedros Adhanom Ghebreyesus has decried such booster campaigns, arguing that rich countries should focus on relieving global vaccine inequality rather than try to “boost our way out of the pandemic.”

Hawaii state epidemiologist Sarah Kemble said in an email the DOH cannot recommend fourth shots for the public at this time.

“Based on current science, there is not evidence to support getting fourth shots to prevent infection or severe outcomes,” Kemble said. “We will continue to update guidance as needed as more information becomes available.”

Both Pfizer and Moderna are forging ahead with second-booster trials anyway, with the former currently testing an omicron-specific shot on Hawaii volunteers.

As for concerns about side effects from additional shots, Baehr said people should stick to the official timetables.

“There are ages and a timetable during which the vaccine should be used, and we would want people to stay within those guidelines because that’s what’s been studied, that’s what’s been researched, and that’s what we know is safe,” Baehr said.