Alex Mutuku

Background: Estimating cause-related mortality among the dead is not common, yet for clinical and public health purposes, a lot can be learnt from the dead. HIV/AIDS accounted for the third most frequent cause of deaths in Kenya; 39.7 deaths per 100,000 population in 2019. OraQuick^® has previously been validated on oral fluid and implemented as a screening assay for HIV self-testing in Kenya among living subjects. We assessed the feasibility and diagnostic accuracy of OraQuick^® for HIV screening among decedents. Methods: Trained morticians collected oral fluid from 132 pre- and post-embalmed decedents aged >18 months at Jaramogi Oginga Odinga Teaching and Referral Hospital mortuary in western Kenya and tested for HIV using OraQuick^®. Test results were compared with those obtained using the national HIV Testing Services algorithm on matched pre-embalming whole blood specimens as a gold standard (Determine^® HIV and First Response^® HIV 1-2-O). We calculated positive predictive values (PPV), negative predictive values (NPV), Area Under Curve (AUC), sensitivity and specificity of OraQuick^® compared to the national HTS algorithm. Results: OraQuick^® had similar sensitivity of 92.6%, (95.0% confidence interval (CI):75.7- 99.1) on pre- and post-embalmed samples compared to the gold standard. Specificity was 97.1% (95.0% CI:91.9-99.4) and 95.2%, (95.0% CI:89.2-98.4) pre and post embalming respectively. Pre and post embalming PPV was 89.3% (95.0% CI:71.8-97.7) and 83.3% (95.0% CI:65.3-94.4) respectively. The AUC pre-and post embalming was 94.9% (95% CI: 89.6 - 100) and 93.9% (95% CI, 88.5 - 99.4) respectively. Conclusions: The study showed a relatively high performance sensitivity and specificity of OraQuick^® HIV-1/2 test among decedents, similar to those observed among living subjects. OraQuick^® HIV-1/2 presents a convenient and less invasive screening test for surveillance of HIV among decedents within a mortuary setting.

Background: 10-valent pneumococcal conjugate vaccine (PCV10), delivered at 6, 10 and 14 weeks of age, was introduced in Kenya in January 2011, accompanied by a catch-up campaign in Kilifi County for children <5 years. Coverage with ≥2 PCV10 doses in children 2-11 months was 80% in 2011 and 84% in 2016; coverage with ≥1 dose in children 12-59 months was 66% and 87%, respectively. Methods: Clinical and microbiological surveillance for invasive pneumococcal disease (IPD) among admissions of all ages at Kilifi County Hospital was linked to the Kilifi Health and Demographic Surveillance System from 1999-2016. We calculated the incidence rate ratio (IRR) comparing the pre-vaccine and post-vaccine eras, adjusted for confounding, and reported percent reduction in IPD as 1-IRR. Annual cross-sectional surveys of nasopharyngeal carriage were conducted from 2009-2016. Findings: Surveillance identified 667 IPD cases in 3,211,403 person-years of observation. IPD incidence in children <5 years fell sharply in 2011 following PCV10 introduction, and remained low (PCV10-type IPD: 60·8 vs 3·2/100,000 [92% reduction; 95%CI: 78, 97]; overall IPD: 81·6 vs 15·3/100,000 [68% reduction; 95%CI: 40, 83]; 1999-2010 vs 2012-2016). PCV10-type IPD also declined significantly in unvaccinated age groups (<2 months, 5-14 years, ≥15 years), with estimated reductions of 100%, 74%, and 81%, respectively. There was no significant change in the incidence of non-PCV10 type IPD. In children aged <5 years, PCV10-type carriage declined by 74% and non-PCV10-type carriage increased by 71%. Interpretation: Introduction of PCV10 in Kenya resulted in a substantial reduction in PCV10-type IPD in children and adults without significant replacement disease. These findings suggest that routine infant PCV10 immunization programmes with catch-up campaigns will provide substantial direct and indirect protection in low-income settings in tropical Africa.