Galveston County was in the middle of a second wave of coronavirus infections in July 2020. One year later, a camp-related outbreak affected more than 150 county residents in June and July, marking the emergence of the delta variant as Houston sees the beginning of a fourth COVID-19 wave.

New coronavirus cases are up 145% in the U.S. from where they were two weeks ago, and COVID-19 hospitalizations are up 90% in the Texas Medical Center over that same time, TMC officials said during a July 20 virtual webinar. Roughly 100 new patients are being hospitalized with COVID-19 each day across the system's hospitals.

The rise in cases marks the beginning of a fourth wave of COVID-19 in Houston, one that can be attributed to the new delta variant of the virus that has become the dominant strain both in the region and the country, TMC officials said July 20. As of July 21—the last time the Galveston County Health District included delta variant updates in its daily coronavirus briefs—the variant has been confirmed in 21 test samples related to a recent church camp outbreak.

As of July 21, the health district confirmed 157 cases in Galveston County residents tied to the outbreak. Of those cases, 20 were identified as breakthrough cases, meaning the person was infected after being fully vaccinated. Six of the breakthrough cases have tested positive for the delta variant, per GCHD.

“I cannot stress enough—there is no reason to not get vaccinated if you’re old enough. There are plenty of vaccines available,” said Philip Keiser, Galveston County local health authority, in a news release from early July. “These vaccines are safe, effective and they offer the best protection against COVID-19 to you, your family and your community.”

As of July 23, there have been 266 total breakthrough cases in Galveston County. This is about a 0.17% breakthrough rate, which is lower than what was expected from studies, per GCHD.

The health district reported two additional COVID-19-related deaths in its daily coronavirus briefing July 23. Both occurred during the week of July 16 in residents over 60 that had pre-existing medical conditions. One resident was not vaccinated and one was partially vaccinated, per GCHD—marking the first instance of a partially vaccinated county resident dying of COVID-19.

GCHD began noting the vaccination status of individuals who died of COVID-19 in approximately late June. Click here to learn more about receiving notifications from the health district.

The average COVID-19 positivity rate in the county fluctuated between 9% and 12% in July 2020, Community Impact Newspaper previously reported. During the week of July 19, 2020, 6% of tested cases were positive, according to GCHD’s weekly trend data. One year later, the rate of positive cases was 14% during the week of July 18.

More than half of eligible county residents are vaccinated against COVID-19: 53.5% of the population age 12 and up has received both doses of the vaccine as of July 22, per the Texas Department of State Health Services dashboard. Keiser previously told Community Impact Newspaper a 60%-70% vaccination rate would signal a return to prepandemic conditions.

Four in every 10 residents age 16 and over were fully vaccinated as of May 5, Community Impact Newspaper previously reported; of residents ages 65 and up, approximately 76% had received at least one vaccine dose at that time, and about 67% were fully vaccinated.

The social disruption of the past year has led to delays in children getting other vaccinations, such as measles, Dr. Peter Hotez, dean of Baylor's National School of Tropical Medicine, said during the July TMC webinar. This could come into play and potentially create public health issues as the school year begins, he said.

"I’m holding my breath as kids get back to school about a potential measles outbreak like we saw in 2019," he said.

Shawn Arrajj contributed to this report.