Transmissible Diseases in Sperm Donation: Viruses, Bacteria and Genetic Risks

In the UK, over ten thousand people each year turn to sperm donation to realise their dream of starting a family. Modern screening methods significantly reduce health risks, but a small residual risk always remains. This article explains which viruses, bacteria, parasites and inherited disorders can be transmitted—and how multi-stage laboratory screening minimises those risks.

Why Multi-Stage Screening Is Essential

Pathogens often go through a window period: they’re present in the donor but not yet detectable by antibody tests alone. That’s why the Human Fertilisation and Embryology Authority (HFEA) and the British Fertility Society (BFS) recommend combining serological assays with PCR and quarantining donor samples for several months before release.

Viruses Detectable in Ejaculate

• HIV – ELISA and PCR testing, plus sample quarantine.
• Hepatitis B & C – antibody and antigen assays to prevent liver damage.
• Herpes Simplex Virus 1 & 2 – PCR testing; low risk in asymptomatic donors.
• Cytomegalovirus (CMV) – IgG/IgM screening; critical for immunocompromised recipients.
• Zika Virus – RT-PCR and antibody testing after travel to endemic areas.
• HTLV I/II – rare but associated with leukaemia.
• Human Papillomavirus (HPV) – PCR for high-risk types (cervical cancer prevention).
• West Nile & Dengue Viruses – important for donors from tropical or subtropical regions.
• SARS-CoV-2 – included in some screening programmes during peak pandemic periods.

Bacteria and Parasites in Semen

• Chlamydia trachomatis – often asymptomatic; can impair fertility.
• Neisseria gonorrhoeae – detected via NAAT or culture swabs.
• Treponema pallidum (Syphilis) – mandatory TPPA and VDRL serology.
• Urogenital Flora such as E. coli and enterococci – can cause inflammation.
• Trichomonas vaginalis – known to reduce sperm quality.
• Mycoplasma/Ureaplasma – often silent, yet inflammatory.

Genetic Risk Factors

• Cystic Fibrosis – CFTR gene analysis
• Tay-Sachs Disease – HEXA mutation screening
• Spinal Muscular Atrophy – SMN1 gene testing
• Sickle Cell & Thalassaemia – haemoglobinopathy panels
• Fragile X Syndrome – FMR1 gene repeat analysis
• Y-Chromosome Microdeletions – linked to severe oligospermia
• Gaucher Disease – relevant for Ashkenazi Jewish donors
• Population-Specific Panels – e.g. Fanconi anaemia, Wilson’s disease

Which Diseases Can Be Ruled Out?

By combining serology, PCR, genetic panels and a multi-month quarantine, laboratories can effectively exclude all relevant viruses, bacteria, parasites and inherited disorders—driving the residual risk to an exceptionally low level.

The Screening Process

1. Health History – comprehensive questionnaire and counselling.
2. Laboratory Tests – antibody, antigen and PCR assays.
3. Genetic Panel – screening for common hereditary conditions.
4. Quarantine – samples stored frozen for at least three months.
5. Retest – confirm absence of new infections before release.

Private Donation vs. Sperm Bank

Licensed sperm banks ensure maximum safety with regulated tests, quarantine protocols and donor registries. Private donations offer a more personal experience and can be less expensive but require bespoke testing and legal agreements.

Conclusion

Sperm donation opens the door to parenthood for many. A thorough, HFEA- and BFS-recommended screening protocol is essential to virtually eliminate the risk of infection or genetic disorder transmission. Trust accredited clinics or vetted platforms—and give your future family the safest possible start.