, and infections in rural populations in central and southern Togo.

BACKGROUND

, and are widespread helminth parasites in the tropics. Their distribution remains difficult to determine as it may change during national disease control programs and with regional mass drug administration (MDA). Epidemiological surveys are of importance to evaluate the geographical distribution of these helminth parasites and the diseases they may cause, however, up to date epidemiological evaluations on and in Togo are rare, and surveys on are important especially under the aspect of MDA of ivermectin which is performed since decades.

METHODS

Dry blood samples ( = 924) were collected from rural populations in the Régions Central and Plateaux in Togo, and analyzed by parasite-specific real-time PCR and ELISA techniques.

RESULTS

Dry blood samples from 733 persons where investigated by real-time PCR tested for DNA of blood-circulating microfilaria, and a prevalence of 14.9% was detected. Distinct differences were observed between genders, positivity was higher in men increasing with age, and prevalence was highest in the Région Plateaux in Togo. IgG4 responses to antigen (OvAg) were studied in 924 persons and 59% were found positive. The distribution of parasite infestation between age and gender groups was higher in men increasing with age, and regional differences were detected being highest in the Région Plateaux. The diagnostic approach disclosed 64,5% positive IgG4 responses to infective third-stage larvae-specific antigen (SsL3Ag) in the surveyed regions. Antigen cross reactivity of SsL3Ag with parasite co-infections may limit the calculated prevalence. Singly IgG4 positive for SsL3Ag were 13.9%, doubly positive for OvAg and SsL3Ag were 35.5% and triply positive for , and were 9.9%.

CONCLUSIONS

Mansonelliasis, onchocerciasis and strongyloidiasis remain prevalent in the surveyed regions, yet with local differences. Our observations suggest that transmission of , may be ongoing. The degree of positive test results in the examined rural communities advocate for the continuation of MDA with ivermectin and albendazole, and further investigations should address the intensity of transmission of these parasites.