According to researchers in the U.S. syphilis which was almost eradicated a decade ago in the developed world, is making a comeback.
The researchers from the U.S. Centers for Disease Control and Prevention (CDC) say the comeback has been fueled by illicit drug use and high-risk sexual behaviours and many doctors are unprepared to recognize and treat it.
The researchers reached this conclusion after carrying out a comprehensive overview of the published literature on the transmission and rates of syphilis in Western Europe and the USA between 2000 and 2007.
The CDC says the rate for syphilis is up for the 7th consecutive year and this has been the case since the beginning of the 21st century in high-income countries.
They suggest that because the disease was well controlled in the 1990s, doctors may not now be screening for it and they say very high rates are being seen in men who have sex with men.
Dr. Kevin Fenton from the National Center for HIV/AIDS, Viral Hepatitis, STD and TB Prevention at the CDC says the resurgence calls for new training efforts among health-care professionals as in many countries doctors may have lost some of the skills needed to diagnose syphilis.
Dr. Fenton says if the issue is not addressed the disease could become far more widespread.
The CDC says in 2007 homosexual and bisexual men accounted for 64 percent of syphilis cases - up from about 5 percent in 1999.
Experts say syphilis infects as many as 12 million people worldwide each year and most cases are acquired through sexual contact with a syphilis sore.
Pregnant women can pass it on to their babies.
Dr. Fenton says there have been other epidemics of sexually transmitted diseases (STD's) which show that even though the initial rise occurs in men who have sex with men, it is unlikely to stay in that group for any length of time.
Fenton says the data suggests there are now increases among heterosexuals in the U.S. and in Europe.
The researchers say swift public health intervention, including screening programs to prevent the spread of the infection, mass media campaigns, efforts to change behaviour in high-risk groups and distribution of condoms are needed.
They suggest that efforts must be made to incorporate and evaluate new diagnostics tools, social network approaches, innovative evidence-based prevention interventions, robust disease surveillance and systematic monitoring and evaluation of prevention, treatment and care activities.
As with many other STD's syphilis raises the likelihood of infection by or transmission of HIV.
Syphilis which first appears as a sore two to six weeks after infection, can progress if not treated to a rash, fever, and eventually can cause blindness, paralysis and dementia.
Syphilis is effectively treated with penicillin.
The study appears in the journal Lancet.