Abstract. We initiated a longitudinal study of Bancroftian filariasis to improve understanding of dynamics and risk factors for infection in villages near Cairo, Egypt. Baseline prevalence rates for microfilaremia and filarial antigenemia for 1,853 subjects more than 9 years of age were 7.7% and 11.2%, respectively. Microfilaria counts, antigen levels, and microfilaremia incidence over a 1-year period were all significantly lower in older people. These findings suggest that humans develop partial immunity to Wuchereria bancrofti over time. One-year incidence rates for microfilaremia and antigenemia were 1.8% and 3.1%, respectively. Filarial antigenemia, IgG4 antibody to recombinant antigen BmM14, and household infection were all significant risk factors for microfilaremia incidence. Microfilaria counts and parasite antigen levels were significantly reduced by diethylcarbamazine therapy, but many infected subjects refused treatment, and most treated people were still infected one year later. Incident infections approximately balanced infections lost to produce an apparent state of dynamic equilibrium.

The Global Program for Elimination of Lymphatic Filariasis calls for mass drug administration for endemic populations outside of sub-Saharan Africa with a single dose of diethylcarbamazine (DEC) and albendazole (Alb) annually for 4-6 years. Single-dose DEC/Alb dramatically reduces blood microfilaria (MF) counts, but most treated subjects fail to completely clear MF after a single dose. A more effective regimen might reduce the number of years required for elimination programs. We performed a randomized clinical trial in Egyptian adults with asymptomatic microfilaremia to compare treatment with seven daily doses of oral DEC (6 mg/kg) and Alb (400 mg) with a single dose of the same combination. We also studied the effect of re-treatment with single-dose DEC/Alb 12 months after the first treatment course. Multi-dose DEC/Alb was significantly more effective than single-dose therapy for reducing and clearing microfilaremia (mean reduction in MF/ml relative to pretreatment counts at 12 months, 99.6% versus 85.7%, with complete clearance in 75% versus 23.1%). The two regimens had similar activity against adult filarial worms, as indicated by serial ultrasound assessments. Neither regimen resulted in complete clearance of filarial antigenemia. There was no difference in adverse events, which were mild to moderate. Blood microfilaria and parasite antigen clearance rates increased following re-treatment. Multi-dose DEC/Alb may be a useful option for filariasis elimination programs, especially in the first year (when enthusiasm for mass drug administration and coverage rates are high), to quickly reduce community MF loads and transmission rates.

We used duplex Doppler sonography to assess effects of diethylcarbamazine and albendazole therapy (DEC/ALB) on adult Wuchereria bancrofti in vivo. The study was performed in clinically normal Egyptian adults with blood microfilaria counts > 80/mL. Motile adult worms were observed before treatment in dilated scrotal lymphatic vessels in 28 of 36 men (78%) and over the proximal extremities in 5 of 22 women (23%). Most worm nests were inactivated in the months following treatment (90% at 12 months). Circulating filarial antigen levels (a marker for living adult worms) also fell dramatically following treatment. Some men had intrascrotal calcifications and/or non-palpable hydroceles detectable by ultrasound before they were treated. New hydroceles and intrascrotal calcifications appeared after treatment in many cases. However, most of these were transient and of no clinical significance. Prevelance rates for hydrocele and intrascrotal calcifications 24 months after treatment were essentially the same as those prior to treatment. These results show that DEC/ALB is highly active against adult W. bancrofti. They also suggest that host responses to dying adult worms are important in the pathogenesis of filarial hydroceles.

Abstract. This study was designed to evaluate the effect of a single dose of diethylcarbamazine (DEC, 6 mg/kg) on Wuchereria bancrofti infections in a low-endemicity setting in Egypt (microfilaremia, or MF, 3.7%, median MF 34/mL). Subjects with MF or filarial antigenemia were treated and restudied 1 year later. Treatment with DEC dramatically reduced blood MF counts, with clearance in 69% of subjects. Treatment also reduced filarial antigen levels, but low clearance rates suggest that some adult worms survived treatment in most patients. Mass treatment was administered in one village; 27 months later, MF prevalence had decreased 84% (from 4.9% to 0.8%). These results show that singledose DEC treatment can have a major effect on MF prevalence rates and levels in low-endemicity settings. Although the World Health Organization advocates repeated multidrug regimens for filariasis elimination, mass treatment with DEC alone may be sufficient to interrupt transmission in areas with low infection intensities and prevalence rates.

Background: A national vaccination campaign for measles and rubella (MR) was conducted in Egypt in the period from October 31 st to November 21 st , 2015, across Egyptian governorates by the Ministry of Health and Population (MOHP), in collaboration with World Health Organization and UNICEF. It targeted 24 million children aged 9 months to 10 years. Objectives: The present survey aimed at evaluating coverage of the MR national vaccination campaign, to identify the gaps and generate sound recommendations for the upcoming campaigns. Methods: A cluster survey was conducted targeting children aged 9 months to less than 10 years. This household survey was carried out in 26 governorates of Egypt. In each governorate 240 interviews were completed. Results: The survey revealed that the campaign achieved an overall coverage of 98.2% compared to 109.8% vaccination coverage as reported by the Ministry of Health (MOH). Some clusters showed below target coverage in a couple of governorates (Port Said 93.3% and Qena 93.8%). Nonvaccinated children constituted 1.8% of all surveyed children. When causes of non-vaccination were enquired about, the most frequently mentioned cause was ignorance of parents about the vaccination campaign (43 children, 38.1%). Conclusion: The MOHP implementation of the national MR campaign was successful and achieved its objective for increased coverage with MR vaccine among the target age group.