For more information
visit Sexual Health NI.
Who is this page for?
This page provides information for the public, people with increased risk of infection, and health and social care professionals.
About blood-borne viruses and STIs
Blood-born viruses (BBVs), including hepatitis B, C and HIV, and sexually transmitted infections (STIs) are important public health issues.
Prevention, testing, vaccination
Many infections can be prevented, tested for and treated. Early diagnosis and treatment help improve health outcomes and reduce the spread of infection.
You can help reduce your risk by:
- practicing safer sex
- using condoms
- not sharing needles or injecting equipment
- using DoxyPEP, PreP, PEP
- getting vaccinated against hepatitis B if you're eligible
- getting tested if you think you've exposed to an infection
For information on reducing your risk, vaccination where appropriate, testing, treatment, and sexual health services:
- Preventing STIs and HIV - Sexual Health NI
- How do I get an STI test? - Sexual Health NI
- Vaccination - Sexual Health NI
- Sexual health vaccination wallet card | HSC Public Health Agency
- HPV vaccination for gay, bisexual or other men who have sex with men | HSC Public Health Agency
- Looking after your sexual health | HSC Public Health Agency
Blood-borne viruses
Blood-borne viruses (BBVs) are infections that can be spread through blood and certain body fluids. The main blood-born viruses are:
Hepatitis
More information can be found on Hepatitis (A, B, C, D, E) | HSC Public Health Agency including prevention, support and vaccination and Hepatitis | nidirect page.
HIV/AIDS
Transmission of HIV is predominantly through sexual intercourse, although it can also be transmitted by blood-to-blood contact and from an HIV-infected mother at birth.
The immediate public health challenges remain consistent across the UK: increasing incidence and prevalence of HIV; early identification of those infected; rising costs of care; inequalities in disease distribution and determinants; and the associated mortality and long-term morbidity.
Find more information about prevention, testing, treatment and support on pages:
Sexually transmitted infections (STIs)
Sexually transmitted infections (STIs) are mainly passed through sexual contact. Many STIs can be prevented, tested for and treated.
Find more information:
For professionals
How the Public Health Agency helps
The PHA works with HSC organisations and community partners across Northern Ireland to:
- prevent the spread of blood-borne viruses and STIs
- promote safer sex and infection prevention
- support vaccination programmes
- improve access to testing and treatment through partner services
- monitor infection trends through surveillance
- provide evidence-based information, guidance and professional resources
Last modified
06 October 2026