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The past decade has witnessed a dramatic increase of anti-retroviral treatment of human immunodeficiency virus (HIV) infected patients in many African countries. Due to costs and lack of currently available commercial viral load assays, insufficient attention has been paid to therapy monitoring through measurement of plasma viral load. This challenge of patient monitoring by tests as viral load, CD4 cell count, and finally HIV drug resistance could reverse achievements already made against HIV/AIDS infection. Loop-mediated isothermal amplification (LAMP) has been shown to be simple, rapid and cost-effective, characteristics which make this assay suitable for viral load monitoring in resource limited settings. This paper describes a revised LAMP assay using primers in the HIV-1 integrase region. The assay can be used for semi-quantitative measurement of HIV-1 group M viral load. The lower limit of detection (LLOD) was determined as 1200copies/mL and lower limit of quantitation (LLOQ) at 9800copies/mL. Sensitivities of 82 and 86% (in 135 and 99 plasma samples respectively from Kenya) and 93% (in 112 plasma samples from Germany) and specificities of 99 and 100% were realized. HIV-1 group O and HIV-2 virus samples were not detected. This LAMP assay has the potential for semi-quantitation of HIV-1 group M viral load in resource limited countries. There is still a need for further improvement by refinement of primers in respect to detection of HIV-1 group M non-B virus.

The loop-amplification mediated isothermal amplification (LAMP) presents characteristics that overcome the limitations associated with the Current limitations of nucleic acid based technologies (NATs) hinder their use in the low resource settings hence overreliance on serological assays which miss hepatitis C virus (HCV) during the long seroconversion period. The LAMP assay would be ideal for early detection of HCV in routine diagnostics and blood transfusion setups in such settings drastically reducing transmission related transfusion. This study validated and tested a reverse transcriptase-LAMP for HCV detection under limited logistical conditions in a low resource setting. Under stringent laboratory conditions, analytical sensitivity and reproducibility were performed using a panel of HCV positive plasma of genotypes 1a, 1b, mixed 1a/1b, 2b, 3a and 4. Cell culture supernatants of HIV-1 B and plasma samples for Hepatitis B virus were used for specificity testing. Upto 227 plasma including 70 (40 RNA positive and 30 negative) from German patients and 157 (43 RNA positive and 114 negative) from Kenyan patients were tested. Kenyan samples were obtained from 121 sero-positive plasma screened from 1121 participants of various cohorts in Kenya. Although LAMP detected upto 102 IU/mL for genotypes 1a, 1b and 2b, a lower detection threshold was established at 103 IU/mL. Overall sensitivity was 94% (PPV 98%) and specificity was 98% (NPV 96%) for RT-LAMP. Sub optimal detection was noted for genotypes 2b, 3a and 4. Sequence analysis revealed mismatches affecting stringency of primer binding at the F1, B1 and the LB primer targets. RT-LAMP shows potential for early HCV diagnosis and screening in low resource settings. Its robustness is however genotype dependent and can be enhanced by designing primers targeting circulating and suspected genotypes. More studies should be done on the possibility of designing multiplex RT-LAMP primers to capture a wide variety of genotypes. The assay remains simple, rapid, and cost effective for nucleic acid detection and is ideal for use in the limited resource settings.

Background: Human TP53 is the gatekeeper for generation of human cells and is highly conserved. Any alteration/mutation to TP53 adversely affects the regulatory function of the protein, potentially resulting in cancer. This study investigated mutations in codons 7 and 249 of TP53, among patients with hepatocellular carcinoma (HCC) and chronic hepatitis B virus (HBV) infection at the Moi Teaching and Referral Hospital (MTRH), Eldoret, Kenya. Methods: In total, 33 HBV-positive patients attending MTRH hospital between September 2013 and July 2017 were purposely selected from medical records for the study; those with HCC were confirmed from the cancer registry. The patients were aged between 25-67 years, with a male-to-female ratio of 1.1:1. Blood samples were collected from the patients. DNA was extracted, amplified and sequenced using TP53 forward and reverse primers. Gene mutation detection and analysis was done on exons 4 and 7 Results: Of the 33 patients, 75.8% were chronically infected with HBV and had HCC; the rest were HBsAg positive without HCC. Homozygous proline was prevalent (54.5%) at exon 4 codon 72, followed by heterozygous Arg/Pro (33.3%) and lastly homozygous Arg/Arg (12.1%,). Pro/Pro allele was frequent in HCC group while Arg/Arg allele was common in patients without HCC. There was no significant association between the HCC and codon polymorphisms (p=0.12). In exon 7, codon 249, 24.2% of patients had an Arg-Ser mutation of which, 75.0% had HCC and 25.0% did not. There was no significant association between HCC patients and codon 249 mutation (p=0.15). Conclusion: TP53 is a gene gate keeper, the mutations under study may dependently play a role in HCC development. This study did not find any association or clear mutational pattern between P53 mutations and HCC development. Therefore, TP53 mutation is a poor indicator for prognosis and a tumor’s biological behavior among HBV-positive subjects in Kenya.

BACKGROUND In Kenya, the availability of a cheap diagnostic service for HIV-exposed infants has helped scale-up access to treatment, and provided a means by which programs that support Prevention of Mother to Child Transmission of HIV can be evaluated. As expected for any large testing program, discrepant and indeterminate results present a significant challenge. METHODS Dried Blood Spots were collected from health centers countrywide and couriered to four laboratories for tests. Results were dispatched either by email, telephone, GSM SMS printer or courier. Between 2006 and 2009, tests were conducted with the Manual Roche v. 1.5 Assay. In 2010 the labs switched fully to the Cobas® AmpliPrep/ Cobas® TaqMan® HIV-1 Qual automated Roche Test. RESULTS Between 2006 and 2010, the KEMRI CVR EID Lab conducted 64 591 HIV tests in on children