The city's world-record lockdowns have not only limited the spread of COVID-19 but also ostensibly STIs, with home visits banned to all but intimate partners and those in single bubbles.

But the return of freedoms and the reopening of Melbourne meeting places such as pubs, cafes and restaurants before this weekend is set to lead to more social interactions, including those of the intimate variety.

The Department of Health's Maria Bubnic says anyone who is sexually active can get or have an STI, and noted sexual health testing fell last year during lockdowns and again in 2021.

"This means people may have an undiagnosed STI and potentially be at risk of passing an STI onto a partner," the executive director of public health said in a statement on Monday.

"That is why it is so important that when restrictions ease, and freedoms return, that people talk to their GP about a sexual health test."

She said sexually active people should get tested for STIs such as HIV, gonorrhoea, syphilis, chlamydia and blood-borne forms of hepatitis every 12 months, or even earlier if they planned to conceive.

Most STIs are curable and all are treatable but if not remedied can cause long-term health conditions, including infertility.

Congenital syphilis, where a baby is born with infectious syphilis, has recently become an emerging public health issue in Victoria.

Cases of the congenital syphilis, which can cause miscarriage and serious birth abnormalities in babies, have increased over the past two years, including two foetal deaths.

The health department says it's a timely reminder for people planning or having a family to get tested.

"It is estimated that around one in every six people will get an STI in their life - and most won't even know it," Ms Bubnic said.

Australian Associated Press