Syphilis cases rising worldwide: what nurses need to know

Syphilis cases in England have reached their highest level since the 1940s, prompting the UKHSA to publish a new action plan to tackle the rising tide of infections.

Jodie Crossman, doctoral research fellow and nurse representative for the British Association of Sexual Health and HIV, outlines the clinical picture and explains why community and practice nurses are well placed to spot the signs and prompt earlier diagnosis.

Syphilis is a treatable and curable multi-system infection caused by the bacteria Treponema Pallidum.¹ Acquired primarily by sexual contact, syphilis was rarely seen in the UK during the 1990s.² However, since the early 2000s, infections have been on the rise.

In recent years there has been a marked increase in diagnoses both globally and across the UK, with 13,000 cases reported in England in 2024 – the highest number since the 1940s.

Although syphilis disproportionately affects gay, bisexual and other men who have sex with men, increases are also being seen among heterosexual men and women, particularly those who experience marginalisation.²

Syphilis is preventable with consistent condom use and a single 200mg dose of doxycycline post exposure prophylaxis (doxyPEP) within 72 hours of condomless sex is recommended for those at an increased risk of acquisition.³

Why are syphilis cases increasing?

As with all sexually transmitted infections, the reasons for an increase in cases are complex and multifaceted and vary across countries and cultures. Changes in sexual behaviour and networks over time, alongside reduced condom use may contribute to a wider distribution of infections.⁴

Reduced access to sexual health services, inequities in access to care, and changes in global surveillance strategies can reduce timely testing and treatment, which also plays a role.² Additionally, people with syphilis often present to non-specialist settings, resulting in missed opportunities for diagnosis.

Clinical presentations: why syphilis is so easy to miss

Syphilis is commonly referred to as ‘the great imitator’ due to widespread, multi-system symptoms that can often mimic the symptoms of other infections.⁴ They can also be mild, fluctuating, and appear to resolve without treatment, which can delay presentation to specialist services.

Syphilis develops in stages and can affect many different parts of the body, which is why it can be difficult to recognise.¹

Primary syphilis

In its early stage (nine to 90 days after acquisition),¹ primary syphilis is classically characterised by a single, painless, shallow ulcer known as a chancre. It is commonly located at the site of infection in the genital or anal area, but it can also appear in the mouth or throat.

Importantly, sores are often painless and heal on their own within a few weeks, which means people may not notice them, and may not seek medical advice. Chancres can also look atypical – they may be painful, multiple or produce discharge – making diagnosis more difficult.

Secondary syphilis

If untreated, around a quarter of people will go on to develop the symptoms of secondary syphilis typically three to ten weeks after the chancre has appeared.

Secondary syphilis is a systemic illness and may present with a widespread rash, often involving the palms of the hands and soles of the feet. Lymphadenopathy – swollen lymph nodes – is also common.

Other signs can include patchy alopecia, painless white patches in the mouth or genital area, and moist wart‑like lesions around the anus or perineum, known as condylomata lata, which are highly infectious.

Some people develop eye or neurological symptoms, such as acute meningitis, uveitis and cranial nerve palsies. Less commonly, syphilis can affect the liver, kidneys or other organs. Symptoms of secondary syphilis often resolve spontaneously within three to 12 weeks.¹

Latent and late-stage syphilis

After the secondary stage of syphilis, the infection enters a latent – symptom‑free – stage, which can last for years. Without treatment, about one third of people eventually develop late syphilis, which can cause serious heart, brain or tissue damage decades later.¹

Late disease is now relatively rare but diagnosed cases did increase by 46% among men in the UK between 2023 and 2024.² Importantly, this stage remains preventable with early diagnosis and treatment.¹

The role of nurses in early detection and signposting

As the symptoms of syphilis are so diffuse and wide ranging, patients often present to services outside of sexual health with varying concerns – such as dermatological or neurological symptoms.

Community and practice nurses play a vital role in thorough history taking, normalising conversations about sexual health, recognising when to recommend testing, and signposting or referring to local sexual health services.

People with syphilis may present for pregnancy care, long‑term condition reviews, or requesting community pharmacy diagnostic services. It is important that syphilis is considered in any differential diagnosis until ruled out.

Testing for syphilis is straightforward, with a simple blood test confirming infection. Moreover, treatment with intramuscular injections of penicillin is highly effective.¹

Congenital syphilis: a re‑emerging and preventable harm

Perinatal transmission of syphilis is also an increasing concern. Syphilis testing via the maternal screening programme has increased early detection but can also fail to capture those who acquire syphilis later in pregnancy, or who do not engage with antenatal care.⁵

Congenital syphilis remains rare but is increasing in the UK, and can have devastating consequences including stillbirth, neonatal death, or lifelong disability.² People particularly at risk of late diagnosis of syphilis during pregnancy include those who have recently arrived in the UK, people with complex social situations where appointment attendance may be deprioritised, or people who do not have English as a first language.

All clinicians working with pregnant people should ensure that screening blood tests are conducted, to avoid the negative consequences of congenital syphilis.

What the UKHSA Syphilis Action Plan means for frontline practice

In response to the rise in syphilis cases, the UK Health Security Agency have published a response plan for England,² aiming to reduce late diagnosis and encourage prompt testing and treatment.

The plan, which builds on the Syphilis Action Plan published by Public Health England in 2019,⁶ has four pillars:

Prevent: reduce transmission, reduce inequalities, increase awareness
Test: optimise testing and reduce missed opportunities for diagnosis
Treat: optimise care pathways
Eliminate: congenital syphilis

Successful reduction in syphilis will rely on collaborative working across all parts of the health service, not just sexual health specialists, to enable a reversal of current trends.

As key stakeholders of frontline practice, community and practice nurses have a vital role in early detection, testing and signposting to sexual health services, which will support timely diagnosis, reduce onward transmission, and ultimately improve patient outcomes.

Jodie Crossman is a doctoral research fellow at University College London and is nurse representative for the British Association of Sexual Health and HIV.