COVID-19 disrupted both surveillance and prevention of sexually transmitted diseases, which have been surging for several years. The Centers for Disease Control and Prevention’s 2020 surveillance report argues that the surge likely continued during the pandemic, even though officials don’t have the test results or final count to prove it.

The CDC said more than 2.4 million cases of chlamydia, gonorrhea and syphilis were reported in the United States in 2020, down slightly from 2019. Those three sexually transmitted infections are “reportable,” meaning public health officials are supposed to be notified when a case is confirmed. The report casts doubt on whether an actual decrease, however small, took place.

“In 2020, the COVID-19 pandemic dramatically disrupted life as we knew it, and while there were moments when it felt like the world was standing still, sexually transmitted infections were not,” Dr. Jonathan Mermin, director of the National Center for HIV, Viral Hepatitis, STD, and TB Prevention, said in a press briefing.

The 2020 numbers include more than 2,100 cases of congenital syphilis — the designation when babies are born with syphilis. That’s a 235% increase from 2016.

Gonorrhea increased 10% between 2019 and 2020, while primary and secondary syphilis cases increased 7%. While reported cases of chlamydia dropped 13%, the center noted that “chlamydial infections are usually asymptomatic and identified through screening. Therefore, this decline is likely due to decreases in STD screening and underdiagnosis during the pandemic, rather than a reduction in new infections.”

The report said that the South had the most reported gonorrhea and chlamydia cases, then the Midwest. The West had the highest number of primary and secondary syphilis, followed by the South.

Early in the pandemic, health agencies saw fewer sexually transmitted diseases, but the cause was more likely to be less screening than any actual decrease in cases, the CDC said. It noted several disruptions from the pandemic, including that fewer people got screened; resources including test kits, staff and laboratory supplies were often diverted to tackle COVID-19; some people lost jobs and thus insurance; and in some cases patients were treated for symptoms with telehealth visits but did not get lab confirmation.

Early 2021 data on syphilis suggests that the year’s final numbers will also show an increase when the final tally is completed.

The center said young people, some racial and ethnic minorities, and gay and bisexual males carry the heaviest burden from STDs.

“Over half of reported STDs were among 16- to 24-year-olds. Racial minorities including Black, Hispanic and Native American people were disproportionately impacted, while 42 % of cases of primary and secondary syphilis were among gay and bisexual males,” according to a ScienceAlert report.

The CDC notes that sexually transmitted infections are often asymptomatic, but it doesn’t mean they are benign. Even symptomless cases increase the risk of HIV infection. And the infections can cause chronic pelvic pain, pelvic inflammatory disease, infertility and pregnancy complications, including infant death.

The U.S. Department of Health and Human Services has a Sexually Transmitted Infections National Strategic Plan that calls for prevention, improved outcomes for those who have the infections, closing health disparity gaps and improving research, among other goals. Priority populations include adolescents and young adults, gay and bisexual men, and pregnant women.

The plan’s recommendations include setting up clinics for walk-in testing and treatment, collaborating with pharmacies and retail health clinics and more telehealth options.