Syphilis: the alarming rise in cases in Lebanon

Once thought a relic of the past, syphilis, a sexually transmitted infection (STI), is making an alarming comeback worldwide. In Lebanon, cases increased by 862% between 2006 and 2019, according to a study conducted at a tertiary care center and published in Panorama of Emergency Medicine in 2024. The researchers found that the infection primarily affects middle-aged men living with HIV.

A similar trend has been observed in other countries. In the United States, the Centers for Disease Control and Prevention recorded an 80% increase in syphilis cases between 2018 and 2022. In Europe, 41,051 confirmed cases were reported in 2023, in 29 EU member states, according to the European Centre for Disease Prevention and Control. The World Health Organization estimated that 8 million adults between 15 and 49 years old acquired syphilis in 2022.

Decline in protective measures

A drop in protective sexual practices seems to be at the root of the problem. “Worldwide, we are witnessing a decline in the number of people newly infected with HIV and an alarming rise of STIs,” noted Professor Jacques Mokhbat, infectious diseases specialist. 

“Thanks to major advances in HIV treatment, the transmission of the virus is well controlled,” he explained. “Nowadays, a person living with HIV whose viral load is undetectable cannot transmit the virus anymore. Consequently, many people have dropped the use of condoms, considering that they are protected and that they protect their partner(s). Furthermore, the introduction of PrEP (a preventive regimen against HIV) leads to more carelessness in sexual protection.”

“Unfortunately, both treatment and preventive treatment do not protect from other sexually transmitted diseases, he added. For the past fifteen years then, we have been observing a dramatic surge in STIs, mainly HPV (human papillomavirus), the leading cause of cervical cancer in women, anal cancer in men, laryngeal and lung cancers, herpes, chlamydia, gonorrhea and syphilis. The latter has re-emerged after being successfully controlled following the introduction of its treatment with penicillin in the 1950s.”

Mokhbat explained that “a new regimen is being prescribed to prevent the transmission of chlamydia, gonorrhea and syphilis.”

Since this protocol is not regularly implemented, we are not expecting to see a decline in STIs for several years. On the other hand, this medicine is not well tolerated. Therefore, it is not used routinely.

Four stages of the infection

Syphilis is an STI caused by the bacterium Treponema pallidum. It is believed that the microbe was brought to Europe from the Americas by Christopher Columbus and his crew in the late15th-early 16th century. The natural course of the infection evolves over a period of 25 years and includes four clinical aspects: primary, secondary, latent and late.

The primary phase usually lasts around 21 days. It includes an ulcer, called a chancre, that appears mainly on the genitals, anus or oral area. It often goes unnoticed and heals within 10 days, without treatment.

The secondary phase is characterized by a body rash, oral and genital mucosal lesions, and generalized lymph nodes that can also disappear spontaneously. This stage may recur repeatedly afterward. 

“The symptoms observed in these two phases resemble those of many other dermatological diseases, which earned syphilis the name ‘The great imitator’,” Mokhbat said. He noted that in the 19th century, the disease was mainly treated by dermatologists. “The identification of the bacterium, in 1905, and the development one year later of a specific blood test, allowed specialists to detect the infection in people who didn’t show symptoms.”

The latent phase, as its names suggest, is symptom-free and can last a lifetime.

The late stage is the most serious. Generally, it appears many years after the initial infection. It may present in three forms: gummatous, in which the inflammatory lesion cause the death of the skin and deeper tissues; vascular, leading to damage the heart and major blood vessels such as the aorta; and neurological, which appears at an advanced stage of the disease, affecting the brain or the spinal cord.

However, since the discovery of penicillin, and with the frequent use of routine laboratory testing, specialists stopped seeing the advanced phases of the disease in their clinics, although these symptoms continued to be taught in medical schools. Nowadays, the first two stages of syphilis are most frequently seen in the clinic.

It is thus important to “treat the infection as soon as it is detected,” Mokhbat insisted. “But the problem is that in many cases, it can go unnoticed, since the body rash disappears quickly.” “Some doctors may miss the infection, as it had become nearly forgotten by many clinicians,” he added.

As a conclusion, the specialist urged individuals at risk to “use protection when having casual sex.” “Medical regimens prescribed to treat HIV don’t protect against syphilis, gonorrhea, chlamydia, HPV or other STIs, although some medications against HIV are active against hepatitis B. Both hepatitis B and C may cause liver cirrhosis and liver cancer. People must act responsibly,” he concluded.