Nearly half of the 9,000-plus new HIV infections in Thailand each year are people aged between 15-24 years old, according to the Department of Disease Control.
Dr Suchada Jiamsiri, chief of the Division of Aids and Sexually Transmitted Infections (STIs), Ministry of Public Health's Department of Disease Control, said infections among this age group have been a trend for several years.
The highest rates used to be among sex workers and the group of men who have sex with other men (MSM), said Dr Suchada, who was speaking with the Bangkok Post for World Aids Day, which falls on Friday.
Dr Suchada said these rates show that young people have paid less attention to the disease and ignored the use of condoms.
She said that the young are likely to care more about the prevention of an unwanted pregnancy at their age, such as by using birth control pills, which have been effective in reducing the number of teenage mothers, but it seems that the condom is the last choice due to perceptions that it will make sex less fun.
"We have a strong concern about this trend, and we have tried our best to raise their awareness about condom use," she said.
Dr Suchada said the department's latest survey found that 77.8% of female middle school students and 59.1% of male students use condoms, and the numbers are 77.6% and 72.5%, respectively, among vocational school students.
She said the department has closely worked with civil society to send a strong message that HIV/Aids can be prevented by having safe sex.
She said the state budget for HIV/Aids management has been reduced because the disease is no longer as big an issue as it once was, while foreign funding that supported local projects to prevent HIV/Aids has also declined for similar reasons.
The National Health Security Office (NHSO) is the main organiser supporting policies on HIV/Aids prevention.
The NHSO provides over 10 million free condoms per year, drugs to prevent disease infection and related tests in hospitals.
There are presently 561,578 people living with HIV in Thailand.
The government has joined a global commitment to end HIV/Aids by 2030, with a target of Thailand reducing newly infected cases to less than 1,000 per year from the present 9,230 cases per year.
The number of deaths linked to HIV/Aids should be less than 4,000 cases per year from 10,970 cases per year, as per the commitment.
Thailand is on track to meet the 95-95-95 Global Aids Strategy of the United Nations, aiming to diagnose 95% of all HIV-positive individuals, provide antiretroviral therapy for 95% of those diagnosed and achieve viral suppression for 95% of those treated by 2025.
By the end of 2022, an estimated 90% of people who were living with HIV/Aids were aware of their status, Dr Suchada said.
About 90% of diagnosed people were on treatment, and 97% of those on treatment achieved a suppressed viral infection, which prevents them from infecting others, she added.