Dementia Prevalence Estimates in Sub-Saharan Africa: Comparison of two Diagnostic Criteria.

We have previously reported the prevalence of dementia in older adults living in the rural Hai district of Tanzania according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) criteria. The aim of this study was to compare prevalence rates using the DSM-IV criteria with those obtained using the 10/66 diagnostic criteria, which is specifically designed for use in low- and middle-income countries. In phase I, 1,198 people aged 70 and older were screened for dementia. A stratified sample of 296 was then clinically assessed for dementia according to the DSM-IV criteria. In addition, data were collected according to the protocol of the 10/66 Dementia Research Group, which allowed a separate diagnosis of dementia according to these criteria to be established. The age-standardised prevalence of clinical DSM-IV dementia was 6.4% (95% confidence interval [CI] 4.9-7.9%) and of '10/66 dementia' was 21.6% (95% CI 17.5-25.7%). Education was a significant predictor of '10/66 dementia', but not of DSM-IV dementia. There are large discrepancies in dementia prevalence rates depending on which diagnostic system is used. In rural sub-Saharan Africa, it is not clear whether the association between education and dementia using the 10/66 criteria is a genuine effect or the result of an educational bias within the diagnostic instrument. Despite its possible flaws, the DSM-IV criteria represent an international standard for dementia diagnosis. The 10/66 diagnostic criteria may be more appropriate when identification of early and mild cognitive impairment is required

Taxonomy of the order Mononegavirales : update 2016

In 2016, the order Mononegavirales was emended through the addition of two new families (Mymonaviridae and Sunviridae), the elevation of the paramyxoviral subfamily Pneumovirinae to family status (Pneumoviridae), the addition of five free-floating genera (Anphevirus, Arlivirus, Chengtivirus, Crustavirus, and Wastrivirus), and several other changes at the genus and species levels. This article presents the updated taxonomy of the order Mononegavirales as now accepted by the International Committee on Taxonomy of Viruses (ICTV)

Development and Validation of the Identification and Intervention for Dementia in Elderly Africans (IDEA) Study Dementia Screening Instrument

Aim: The aim of this project was to develop a dementia screening instrument for use in the hospital or community in populations with low levels of formal education. Methods: A screening instrument was developed from retrospective data collected in a rural area of Tanzania in 2010. The community screening instrument for dementia was administered to over 95% of the population aged 70 years and older of 6 villages (n ¼ 1198) in Hai district, Tanzania. Factor analysis, regression modeling, and Mokken scale analysis (MSA) were used to develop screening instruments from these data, which were then tested and refined during prospective fieldwork. Results: A 5-item screening instrument with an area under the receiver–operating characteristic (AUROC) curve of 0.871, sensitivity of 91.7%, and specificity of 61.7% was developed using a combination of factor analysis and logistic regression modeling and had a higher AUROC (0.786) than a 7-item screening instrument developed using MSA. During prospective testing and refinement (n ¼ 60), the 5-item instrument performed well (AUROC 0.867) and took an average of less than 10 minutes to administer. Its performance was improved by including a matchstick design item added to measure praxis, AUROC 0.888. Conclusions: The 6-item brief dementia screening instrument has acceptable properties and will be further tested and validated during future fieldwork. Although developed for use in sub-Saharan Africa, it may be of use in other world regions where the use of other cognitive screening instruments may result in bias due to low levels of formal education

The association between disability and cognitive impairment in an elderly Tanzanian population

Cognitive impairment is thought to be a major cause of disability worldwide, though data from sub-Saharan Africa (SSA) are sparse. This study aimed to investigate the association between cognitive impairment and disability in a cohort of community-dwelling older adults living in Tanzania. The study cohort of 296 people aged 70 years and over was recruited as part of a dementia prevalence study. Subjects were diagnosed as having dementia or mild cognitive impairment according to the DSM-IV criteria. Disability level was assessed according to the WHO Disability Assessment Schedule, version 2.0 (WHODAS). A higher WHODAS score indicates greater disability. The median WHODAS in the background population was 25.0; in those with dementia and in those with mild cognitive impairment, 72 of 78 (92.3%) and 41 of 46 (89.1%), respectively, had a WHODAS score above this level. The presence of dementia, mild cognitive impairment, hearing impairment, being unable to walk without an aid and not having attended school were independent predictors of having a WHODAS score above 25.0, though age and gender were not. In summary, cognitive impairment is a significant predictor of disability in elderly Tanzanians. Screening for early signs of cognitive decline would allow management strategies to be put in place that may reduce the associated disability burden

ICTV virus taxonomy profile: Rhabdoviridae

The family Rhabdoviridae comprises viruses with negative-sense (-) single-stranded RNA genomes of 10.8-16.1 kb. Virions are typically enveloped with bullet-shaped or bacilliform morphology but can also be non-enveloped filaments. Rhabdoviruses infect plants and animals including mammals, birds, reptiles and fish, as well as arthropods which serve as single hosts or act as biological vectors for transmission to animals or plants. Rhabdoviruses include important pathogens of humans, livestock, fish and agricultural crops. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the taxonomy of Rhabdoviridae, which is available at www.ictv.global/report/rhabdoviridae

Taxonomy of the order Mononegavirales: update 2016.

In 2016, the order Mononegavirales was emended through the addition of two new families (Mymonaviridae and Sunviridae), the elevation of the paramyxoviral subfamily Pneumovirinae to family status (Pneumoviridae), the addition of five free-floating genera (Anphevirus, Arlivirus, Chengtivirus, Crustavirus, and Wastrivirus), and several other changes at the genus and species levels. This article presents the updated taxonomy of the order Mononegavirales as now accepted by the International Committee on Taxonomy of Viruses (ICTV)

Taxonomy of the order Mononegavirales: update 2016

In 2016, the order Mononegavirales was emended through the addition of two new families (Mymonaviridae and Sunviridae), the elevation of the paramyxoviral subfamily Pneumovirinae to family status (Pneumoviridae), the addition of five free-floating genera (Anphevirus, Arlivirus, Chengtivirus, Crustavirus, and Wastrivirus), and several other changes at the genus and species levels. This article presents the updated taxonomy of the order Mononegavirales as now accepted by the International Committee on Taxonomy of Viruses (ICTV)