by Michael Woodhead  

Trichomonas vaginalis has dropped off the radar but it is re-emerging and may affect as many as one in five women with cervicitis, a new Australian study suggests.  

After peaking in the 1950s, Trichomonas vaginalis infection is now assumed to be rare and is rarely tested for, say the authors of a study carried out at a Sydney STI clinic.  

Writing in the journal Sexually Transmitted Infections (online 1 November), they say the use of newer PCR detection methods shows that the infection is often missed by traditional testing method of wet preparation microscopy.  

In a prospective study of 356 women attending two urban STI clinics, they found that the prevalence of Trichomonas vaginalis was 5% with PCR testing, but only 1% when tested by traditional detection methods.   Most of the women with the infection were from migrant backgrounds, and three had a rural background or connections.  

The study authors say dysuria was a common feature “highlighting the need for clinicians to consider the possibility of Trichomonas vaginalis especially in the absence of other causes of dysuria.”  

“Our data show that traditional  methods of detection greatly underestimate the prevalence of Trichomonas vaginalis,” they write.  

The say the infection may also be masked by the presence of bacterial vaginosis and be eradicated with nitroimidazole drugs. However, the infection would return and persist if partners are not treated as well.  

They conclude that clinicians should be aware of the potential re-emergence of Trichomonas vaginalis, which could have a significant impact on women’s reproductive health.