STI Prevalence in Lagos 2025
What the Data Actually Shows

HIV in Lagos: The Numbers in 2025

Lagos State has an HIV prevalence of approximately 1.4% among adults, below the national average of 1.7% but representing hundreds of thousands of people in absolute terms given Lagos's population. NAIIS data estimates that approximately 600,000 Nigerians are HIV-positive but unaware of their status. The highest rates in Lagos are in specific high-risk populations.

The treatment picture has improved significantly: Nigeria's national ART programme now covers approximately 1.5 million people. U=U (Undetectable = Untransmittable) has transformed the lives of HIV-positive Nigerians on effective treatment. The challenge remains the testing gap, people who don't know their status cannot access treatment.

Gonorrhoea: An Antibiotic Resistance Emergency

Neisseria gonorrhoeae antibiotic resistance is one of the most pressing public health concerns in Nigerian sexual health. Studies from Lagos consistently show ciprofloxacin resistance rates exceeding 80%, and emerging resistance to azithromycin has been reported. The current recommended treatment (dual ceftriaxone + azithromycin) remains effective but requires intramuscular injection rather than oral tablets, increasing the barrier to appropriate treatment.

The consequence of this resistance landscape is that the most commonly purchased antibiotic for gonorrhoea in Lagos (ciprofloxacin from a pharmacy without prescription) fails in the majority of cases. The infection is temporarily suppressed, the patient feels better, but bacteria persist and the patient remains infectious and at risk of complications.

Syphilis: The Resurgence

Syphilis is resurging globally: including in Nigeria. Nigerian studies report syphilis prevalence of 2–5% in antenatal populations and significantly higher rates in specific risk groups. Congenital syphilis (transmitted from untreated mother to baby) causes stillbirth, neonatal death, and multi-organ damage, and is entirely preventable with antenatal syphilis testing and penicillin treatment.

Chlamydia: The Invisible STI

Chlamydia trachomatis causes no symptoms in approximately 70% of women and 50% of men. It is the leading preventable cause of tubal infertility and ectopic pregnancy. Lagos STI data consistently underestimates chlamydia burden because it is almost never tested for without symptoms, the test must be actively requested. Annual chlamydia screening for sexually active women under 25 is standard guidance in most high-income countries but largely absent in Nigerian practice.

About this article: Written by the Mascot Healthcare clinical team. This article is reviewed annually and updated to reflect current guidelines and data.