STI Prevention and Essential Knowledge - Protecting Yourself and Your Partner

About a 4 min read.

STIs Are Not Someone Else's Problem

According to statistics from Japan's Ministry of Health, Labour and Welfare, reported syphilis cases reached an all-time high in 2023. Chlamydia and gonorrhea infections are also on the rise, particularly among younger populations. STIs are not diseases that only affect certain people; anyone who is sexually active is at risk.

Many STIs show no symptoms in their early stages, meaning carriers can unknowingly transmit infections to partners. Having accurate knowledge is the first step in protecting yourself and your partner's health. Stigma and shame surrounding STIs contribute to delays in testing and treatment. STIs, like colds and influenza, are infections that anyone can contract; they should be understood as a public health issue, not a moral one.

Major STIs and Their Characteristics

Chlamydia

The most frequently reported STI. Approximately 80 percent of infected individuals show no symptoms, yet untreated chlamydia can cause salpingitis and pelvic inflammatory disease, potentially leading to infertility. It is curable with antibiotics, but both partners must be treated simultaneously to prevent reinfection. Treating only one partner leads to "ping-pong infection," where the untreated partner reinfects the other.

Syphilis

A rapidly increasing infection in recent years. Early symptoms include painless sores and rashes that may disappear on their own, making the infection easy to overlook. It is treatable with penicillin-based antibiotics, but if it progresses, it can cause serious damage to the nervous system and heart as neurosyphilis or cardiovascular syphilis. Syphilis is called "the great imitator" because it presents such diverse symptoms; when in doubt, early testing is crucial.

HIV

Advances in treatment mean that starting therapy early allows individuals to lead normal lives. The concept of U=U (Undetectable = Untransmittable) is internationally recognized, meaning that maintaining viral load below detectable levels through proper treatment effectively reduces the risk of sexual transmission to zero.

HPV (Human Papillomavirus)

The most common STI, with approximately 80 percent of sexually active people contracting it at some point in their lives. Most infections clear naturally, but certain strains can cause cervical cancer, throat cancer, and anal cancer.

The Basics of Prevention

Correct condom use is the most effective prevention method. Using a condom from start to finish during every sexual encounter is essential. Since oral sex also carries infection risk, dental dams are also recommended.

When used correctly, condoms significantly reduce the risk of STIs transmitted through bodily fluids, such as chlamydia, gonorrhea, and HIV. However, they do not provide complete protection against infections spread through skin contact, such as herpes and HPV. For those with latex allergies, polyurethane or polyisoprene condoms are available as alternatives. (Specialized books on sexual health provide systematic learning on this topic)

Regular testing is also part of prevention. Ideally, both partners should get tested before beginning a new relationship.

How to Get Tested

Public health centers offer free and anonymous testing for HIV and syphilis. Testing is also available at urology and gynecology clinics, and home testing kits allow specimen collection at home.

It is important to know that test results can include false positives and false negatives. For HIV testing in particular, there is a "window period" (typically 4 to 12 weeks) between infection and when antibodies become detectable, during which a person may test negative despite being infected. If there is concern, retesting after an appropriate interval is recommended.

When suggesting testing to a partner, frame it not as "I suspect you" but as "I want to protect both our health." Making regular testing a shared habit allows both partners to enjoy intimacy with peace of mind. (Introductory books on infection prevention can help deepen your knowledge)

HPV Vaccination as a Preventive Measure

Vaccination can prevent infection with human papillomavirus (HPV), which causes cervical cancer. In Japan, HPV vaccination has been part of the routine immunization schedule since 2013. The 9-valent vaccine (Silgard 9) covers nine HPV types and is estimated to prevent approximately 90 percent of cervical cancers. Vaccination is recommended for both men and women, and while it is most effective before the onset of sexual activity, adults can still benefit from it.

Key Takeaways

• Many STIs are asymptomatic and can only be detected through testing
• Correct condom use is the most effective prevention, though it has limitations against skin-contact infections
• Public health centers offer free and anonymous testing; be aware of the window period
• HPV vaccination can prevent approximately 90 percent of cervical cancers

Summary - Knowledge Is the Best Defense

STI prevention is built on the accumulation of accurate knowledge and responsible behavior. Rather than looking away out of embarrassment, make prevention and regular testing a part of your daily life to protect yourself and your partner's health.