Countrywide roll-out of Xpert(®) MTB/RIF in Swaziland: the first three years of implementation

SETTING

All 19 public health laboratories in Swaziland that had Xpert(®) MTB/RIF machines installed as part of a countrywide roll-out between June 2011 and June 2014.

OBJECTIVE

To evaluate the utilisation and functionality of Xpert from 2011 to mid-2014.

DESIGN

Descriptive study of Xpert implementation using routinely collected data.

RESULTS

Of 48 829 Xpert tests conducted, 93% were successful: 14% detected Mycobacterium tuberculosis and 12% showed rifampicin resistance. The most common cause of unsuccessful tests was an 'Error' result (62%). Similar findings were obtained in government-supported and partner-supported laboratories. Annual utilisation of Xpert improved from 51% of maximum capacity in 2011 and 2012 to 74% in 2013 and 2014. A monitoring and supervision exercise of all Xpert testing sites in 2014 showed a generally good performance, with over 50% of laboratories achieving a ⩾80% score on most components. However, poor scores were obtained with equipment use and maintenance (6% achieving a score of ⩾80%), internal audit (19% achieving a score of ⩾80%) and process control (25% achieving a score of ⩾80%).

CONCLUSION

Countrywide roll-out of Xpert in Swaziland has been successful, although operational issues have been identified and need to be resolved.

A panel of polymorphic bovine, ovine and caprine microsatellite markers

A panel of 81 new polymorphic bovine microsatellite markers is described, together with further information on a previously reported group of 16 markers. The mean polymorphism information content of the 97 markers determined in 20 cattle was 0.66. Seventy-three of these markers have been assigned to chromosomes by either linkage analysis or use of hybrid cell panels. Thirty-nine of the markers were polymorphic in sheep, and 32 were polymorphic in goat. This study identified a set of 18 robust markers that were polymorphic in all three species and that covered 14 bovine chromosomes. This provides a single group of markers, which would be suited to genetic distance analysis and parentage control in cattle, sheep and goat.

A polymorphism in randomly amplified DNA that differentiates the Y chromosomes of Bos indicus and Bos taurus

A small number of west African Bos taurus cattle breeds, including the N'Dama, constitute a valuable genetic resource by virtue of their ability to remain productive under trypanosomiasis challenge. However, introgression of Bos indicus genes into the trypanotolerant breeds, particularly by introduction of zebu bulls, is a threat to this resource. This work describes the characterization and cloning of a bovine randomly amplified polymorphic DNA (RAPD) that is generated in polymorphic DNA (RAPD) that is generated in polymerase chain reaction (PCR) with the 10 base primer ILO1065 from Bos indicus male templates, but not from B. taurus male templates or female templates of either type. Male-specific sequences with homology to the RAPD also occur in B. taurus breeds. This suggests that the polymorphism may be due to base substitution(s) in an ILO1065 priming site, or insertion/deletion events either affecting priming sites or occurring between sites on the cattle Y chromosome. We have shown that cattle, whether of B. indicus or B. taurus phenotype, which possess a typically B. indicus metaphase Y chromosome on the basis of QFQ banding, have a B. indicus ILO1065-generated genotype. The ILO1065-primed RAPD can be used in a simple dot blot assay as a probe of RAPD-PCR products, to provide a convenient, reliable and effective means of detecting introgression of zebu genes in B. taurus cattle populations.