Periodontal status of a subject sample of Yemen

Abstract From August to October 1991, the periodontal status of 1001 Yemenis representing the age groups 12-14, 15-19, 20-24 and 35-44 years was recorded and evaluated with preference to the CPITN, the calculus index and clinical attachment levels. The impact of chewing khat, the leaves of a cultivated, alkaloid shrub, and of using the traditional miswak chewing stick for oral hygiene purposes were investigated. The results show that 6.9% of the juvenile probands (15-19 years) had healthy periodontal tissue (CPITN 0). whereas bleeding on probing and calculus (CPITN 1+2) were registered in 86.2%. In the 35-44 year age group. 1.7% were periodontally healthy, whereas 84.5% displayed plaque retention or shallow pocketing (CPITN 2-3) and 12.5% deep pocketing (CPITN 4). The treatment needs in all age groups are confined primarily to calculus removal and instruction in oral hygiene. The clinical attachment level and the calculus index revealed age-related attachment loss and calculus formation, primarily among male probands. The higher khat consumption among the male population is reflected in its detrimental effect on the periodontal tissue, especially among younger probands. Oral hygiene aids have also an influence on periodontal status, with a toothbrush proving more efficient than the miswak. WHO efforts directed towards prophylactic programs need to be intensified but can be staffed by dental hygienists.     

Prevalence of the Sickle Cell Gene in Yemen: A Pilot Study

To determine the prevalence of the sickle cell gene (β^S) in Yemen and amongst people from different regions of the country living in the capital, Sana'a City, cord blood samples from 1,500 consenting mothers were collected from hospitals in Sana'a City between July and December 2001. The names and original homes of the parents were recorded. Cation exchange high performance liquid chromatography (HPLC) analysis was used for screening, while isoelectric focusing (IEF) and DNA polymerase chain reaction (PCR) were used to confirm Hb S [β6(A3)Glu→Val]. Thirty‐three samples were found to show Hb FAS, giving an overall likely β^S gene frequency of 0.011. The β^S gene frequency varied with the part of the country from which the parents came. Amongst people from Taiz and Haja in the west, the gene frequency was more than 0.04, but less than 0.004 amongst people from Ibb, adjacent to the governorate (administrative division) of Taiz. Of 66 chromosomes from babies carrying the β^S gene, only 1.5% also carried the ? 158 (C→T) ^Gγ‐globin gene XmnI site compared with 16.1% of 168 chromosomes from babies without the β^S gene from the same regions. The results of this study show a higher β^S gene frequency in the western coastal part of Yemen than in the central mountainous and eastern desert areas. The incidence of affected homozygous births may therefore reach 20/10,000 in certain areas, although it is much lower than this overall. Limited health resources can best be invested in developing a program of education, screening and health care, initially prioritizing those communities residing in the western areas of Yemen with the highest β^S gene frequency.     

Process evaluation of school-based peer education for HIV prevention among Yemeni adolescents

In 2005, a survey was conducted among all the 27 high schools of Aden, which revealed low levels of knowledge on major prevention measures, and a high level of stigma and discrimination towards people living with HIV (PLWH). The results served as a baseline for implementing a school-based peer education intervention for HIV prevention in the 27 schools of Aden. In 2008, and after 3 years of implementation, a quasi-experimental evaluation was conducted, which revealed that the peer education intervention has succeeded in improving HIV knowledge and skills; and in decreasing stigmatization of PLWH. This process evaluation aims to give a deeper understanding of the quasi-experimental evaluation which was conducted in the 27 high schools of Aden, and to highlight the factors that facilitated or inhibited school peer education in such a conservative Muslim setting. Qualitative methodologies were pursued, where 12 focus group discussions and 12 in-depth interviews were conducted with peer educators, targeted students, school principals, social workers, and parents of peer educators. Results revealed that school-peer education was well received. There was an apparent positive effect on the life skills of peer educators, but the intervention had a lesser effect on targeted students. Key enabling factors have been the high quality of training for peer educators, supportive school principals, and acceptance of the intervention by parents. These findings are important for improving the life skills and peer education intervention at the school level, and in better planning and implementation of life skills and peer programmes at a national scale.     

Significant differences between Yemenite and Egyptian STR profiles and the influence on frequency estimations in Arabs

A population genetic study was performed on Yemenites using the set of nine short tandem repeat loci (STRs) D3S1358, VWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317 and D7S820. Analysis of the data revealed that all loci were in Hardy-Weinberg equilibrium and evidence of linkage equilibrium was found for only 1 out of 36 locus pairs. At seven loci the allelic distributions found in the Yemenite sample were significantly different from those found for an Arab population sample from Egypt. Nevertheless, we assume that the Yemenite database can be used for Arabs of unknown or foreign (non-Yemenite) origin in the absence of population-specific databases without exerting a significant bias on the biostatistical interpretation. In an experimental set-up (ethnic profile frequency ratio test), the impact of calculating multi-locus profile frequencies for foreign Arab individuals (Egyptians) using the Yemenite database instead of a region-specific one was negligible. Received: 14 November 1999 / Accepted: 5 April 2000     

Who develops severe malaria? Impact of access to healthcare,socio‐economic and environmental factors on children in Yemen: a case‐control study

Objective To investigate the impact of socio‐economic and environmental factors on developing severe malaria in comparison with mild malaria in Yemen. Method Case‐control study comparing 343 children aged 6 months to 10 years diagnosed with WHO‐defined severe malaria (cases) at the main children’s hospital in Taiz and 445 children with mild malaria (controls) diagnosed in the health centres, which serve the areas where the cases came from. Results In univariate analysis, age <1 year, distance from health centre, delay to treatment and driving time to health centre were associated with progression from mild to severe malaria. In multivariate analysis, distance to nearest health centre >2 km was significantly associated with progression to severe disease. Environmental and vector control factors associated with protection from acquiring malaria (such as sleeping under bednets) were not associated with protection from moving from mild to severe disease. Conclusions Innovative ways to improve access to antimalarial treatment for those living more then 2 km away from health centres such as home management of malaria, especially for infants and young children, should be explored in malaria‐endemic areas of Yemen.     

Thalassemia Trait in Outpatient Clinics of Sana'a City,Yemen

Blood samples were collected from 699 patients attending out patient clinics in Sana'a City, Yemen, to obtain some idea of the prevalence of the thalassemias in our country. Complete blood count, hemoglobin (Hb) electrophoresis, quantitation of Hb A₂ and Hb F, and serum ferritin were determined. Microcytic, hypochromic red cells were found in 103 subjects (14.7%). Iron deficiency alone accounted for only a small proportion of these (n = 12), whereas features suggestive of β‐thalassemia (β-thal) were present in 31 patients (4.43%) and features suggestive of α-thal trait were found in 60 patients (8.6%). The study showed that thalassemia probably accounts for most red cell microcytosis in these out patient clinics, and could represent a significant health problem through births of homozygotes and compound heterozygotes with severe disorders. This pilot study should be repeated with improved technology, and extended to include globin gene analysis to define the nature of the disorders that remain poorly diagnosed.     

Phytochemical screening and antiviral activity of some medicinal plants from the island Soqotra

Methanol and hot-aqueous extracts of 25 different plant species, used in Yemeni traditional medicine and growing, partly as endemic plants, on the island Soqotra have been investigated for their antiviral activity. In addition, the phytochemical identification of the main chemical constituents was performed. The extracts were assayed in two in vitro viral systems, which used influenza virus type A/MDCK cells and herpes simplex virus type 1/Vero cells, at non-cytotoxic concentrations. The herpes simplex virus type 1 showed more sensitivity than the influenza virus type A against the extracts investigated. The methanol extracts of Boswellia ameero, Boswellia elongata, Buxus hildebrandtii, Cissus hamaderohensis, Cleome socotrana, Dracaena cinnabari, Exacum affine, Jatropha unicostata and Kalanchoe farinacea showed anti-influenza virus type A activity with 50% inhibition (IC50) concentrations ranging from 0.7 to 12.5 microg/mL. In addition, 17 plants of the 25 investigated exhibited anti-HSV-1 activity. The antiviral activity of some active extracts was also observed on a molecular level.