Millions of Texans skip their 2nd dose
Health experts warn one shot not enough with delta spreading
Rayy Ball is one of 1.2 million Texans who have not returned for their second COVID-19 vaccine dose more than 90 days after their first shot.
The Tarrant County resident has moved twice in the last few months from one precarious living situation to another, and transportation can sometimes be a problem. In March, Ball had an appointment scheduled for the Moderna vaccine but decided to take the Johnson & Johnson oneshot because it meant not returning for a second appointment.
In late May, Ball became nervous about the efficacy of the Johnson & Johnson vaccine, especially against the hypercontagious delta variant. With concerts and other in-person events on the calendar, Ball decided to make an appointment for one of the mRNA vaccines.
“I wanted an extra bit of protection, and I wanted a booster shot because I felt that Johnson & Johnson wouldn’t protect me,” Ball said. “I went to a different city than I went to for the first one.”
When it was time to return for the second dose of the Moderna series, Ball didn’t go to the appointment after technically already receiving two doses.
“I didn’t really need a third shot, and I saw some studies about delaying intervals before the second shot would produce more of an antibody effect,” Ball said. “A huge part of it is that I didn’t want to go out to a third vaccine clinic. I’m not convinced a third shot would offer me more protection.”
Dr. Wesley Long, a microbiologist and medical director of diagnostic microbiology at Houston Methodist, said it’s difficult to know the real-time effects of mixing and matching vaccine types.
“We don’t know what happens for those who take Johnson & Johnson with an mRNA booster,” Long said. “There’s no real incentive for Johnson & Johnson to study boosting with someone else’s vaccine either. It is learning on the fly, for sure.”
Long does not recommend mixing and matching vaccines.
In total, nearly 2 million Texans are due for their second COVID-19 vaccine dose, according to the Texas Department of State Health Services, meaning they have passed the 21-day mark after their first Pfizer dose or 28 days
after a dose of Moderna.
However, some of these people may be receiving their second dose today or tomorrow, said Douglas Loveday, a DSHS spokesperson.
“Whether it’s two days, two weeks or two months after a person is eligible for that second dose, the (Centers for Disease Control and Prevention) and DSHS encourage Texans to complete their vaccine series and get that second dose for maximum protection,” Loveday said. “With the delta variant still prevalent in the state, the protection afforded by two doses of the vaccine is critical to help slow new, and especially, severe cases.”
At the Houston Health Department, 6,204 people who received a first dose are “overdue” for their second dose, meaning at least 43 days have passed since their first shot, said Porfirio Villarreal, department spokesperson. Countywide, the number climbs to 14,000.
“It typically takes two weeks after vaccination for the body to build protection against the virus that causes COVID-19,” said Samuel Bissett, spokesperson for Harris County Public Health. “That means it is possible a person could still get COVID-19 before or just after vaccination, and then get sick because the vaccine did not have enough time to build protection.”
Before the delta variant, scientists thought one vaccine dose was better than nothing, but two doses were optimal, said Dr. Catherine Troisi, an epidemiologist with UTHealth School of Public Health.
The delta variant changed the level of antibodies people need for protection because of its transmissibility, she said.
“With delta, one dose doesn’t protect you very much,” Troisi said. “It’s almost like not being vaccinated, but that will vary from person to person. Some may respond well to the first dose. But if you look at it overall, there is not a whole lot of protection from delta with one dose.”
Other vaccines, such as the one for hepatitis B, work most effectively in a three-dose schedule, with a second dose one month after the first and a third dose at the six-month mark, she said. In those cases, people who complete their first two doses and skip the third have lower antibody levels after six months than those who received the third dose.
COVID vaccines are new, and Troisi has not heard of any studies calculating the antibody level of people with one dose compared with two doses. Her guess is that antibodies would
wane faster.
“If you have missed it by a week or two or three, go ahead and get the second dose,” she said.
In Texas, 14.5 million people are fully vaccinated with two doses of either Pfizer or Moderna or one dose of Johnson & Johnson, according to state data.
In Harris County, 63.3 percent of residents 12 and older are fully vaccinated, according to DSHS.
Following slow vaccination numbers in late spring and summer, County Judge Lina Hidalgo announced a vaccine incentive program offering $100 gift cards to unvaccinated residents taking their first shot. She credited the program with increasing the county's vaccinations in the month of August — from 83,000 per week in early August to 112,000 per week at the end of the month, according to DSHS data.
Loveday said it’s likely some of the 1.2 million people who are overdue received their second dose in another state, which would not be reported to the state of Texas.
Bissett recommends anyone who still needs a second dose in Harris County call 832-927-8787 or visit https://vacstrac.hctx.net/ landing. If you have missed the dose by more than 43 days, talk with your health care provider about what you should do next.