Neglected Tropical Diseases of the Middle East and North Africa: Review of Their Prevalence, Distribution, and Opportunities for Control

The neglected tropical diseases (NTDs) are highly endemic but patchily distributed among the 20 countries and almost 400 million people of the Middle East and North Africa (MENA) region, and disproportionately affect an estimated 65 million people living on less than US$2 per day. Egypt has the largest number of people living in poverty of any MENA nation, while Yemen has the highest prevalence of people living in poverty. These two nations stand out for having suffered the highest rates of many NTDs, including the soil-transmitted nematode infections, filarial infections, schistosomiasis, fascioliasis, leprosy, and trachoma, although they should be recognized for recent measures aimed at NTD control. Leishmaniasis, especially cutaneous leishmaniasis, is endemic in Syria, Iran, Iraq, Libya, Morocco, and elsewhere in the region. Both zoonotic (Leishmania major) and anthroponotic (Leishmania tropica) forms are endemic in MENA in rural arid regions and urban regions, respectively. Other endemic zoonotic NTDs include cystic echinococcosis, fascioliasis, and brucellosis. Dengue is endemic in Saudi Arabia, where Rift Valley fever and Alkhurma hemorrhagic fever have also emerged. Great strides have been made towards elimination of several endemic NTDs, including lymphatic filariasis in Egypt and Yemen; schistosomiasis in Iran, Morocco, and Oman; and trachoma in Morocco, Algeria, Iran, Libya, Oman, Saudi Arabia, Tunisia, and the United Arab Emirates. A particularly noteworthy achievement is the long battle waged against schistosomiasis in Egypt, where prevalence has been brought down by regular praziquantel treatment. Conflict and human and animal migrations are key social determinants in preventing the control or elimination of NTDs in the MENA, while local political will, strengthened international and intersectoral cooperative efforts for surveillance, mass drug administration, and vaccination are essential for elimination

Albendazole Microparticles Prepared by Spray Drying Technique: Improvement of Drug Dissolution

Purpose: To enhance the dissolution of albendazole (ABZ) using spray-drying technique.Method: ABZ binary mixtures with Kollicoat IR® (KL) and polyvinyl  pyrrolidone (PVP) in various drug to polymer ratios (1: 1, 1: 2 and 1; 4) were prepared by spray-drying. The spray-dried particles were characterized for particle shape, and dissolution rate as well as by differential scanning calorimetry(DSC) and Fourier transform infrared (FTIR).Results: Scanning electron micrographs showed a homogeneous distribution of ABZ in the polymer matrix for ABZ-PVP spray-dried system in ratios of 1: 2 and 1: 4, while it was observed only upon using a ratio of ABZ: KL 1: 4 in case of ABZ-KL systems. FT-IR spectra of both physical mixtures and spraydried mixtures did not show any change for all ABZ-polymer systems, thus indicating the compatibility of the carriers with ABZ. ABZ exhibited a noticeable enhanced dissolution rate from its spray-dried coacervate with PVP and this was independent of the drug/polymer ratio. Drug release was 78, 81 and 81 % from the  spray-dried ABZ-PVP systems of drug: polymer ratio of 1:1, 1:2 and 1: 4, respectively, within 5 min. Drug showed complete dissolution within 15 min. On the other hand, enhancement of dissolution rate varied with ABZ: Kl ratio.Conclusion: Enhancement of ABZ dissolution for both types of spray-dried particles is due to the reduction in drug particle sizes, wetting of the dissolution medium by the hydrophilic carriers and the amorphosization of the drug crystals by the carriers.Keywords: Albendazole, Spray-drying, Kollicoat, Polyvinyl pyrrolidone, Dissolution, Amorphou