Evaluation of AFP surveillance indicators in polio-free Ghana, 2009-2013.

BACKGROUND: Ghana recorded the last case of indigenous wild poliovirus in 1999 but suffered two more outbreaks in 2003 and 2008. Following the World Health Organization (WHO) guidelines, transmission was interrupted through high routine immunisation coverage with live-attenuated oral polio vaccine (OPV), effective acute flaccid paralysis (AFP) surveillance and supplementary immunisation activities (SIA). This article describes the results of a five-year surveillance of AFP in polio-free Ghana, evaluate the surveillance indicators and identify areas that need improvement. METHODS: We investigated 1345 cases of AFP from children aged less than 15 years reported to the Disease Surveillance Department from January 2009 to December 2013. Data on demographic characteristics, vaccination history, clinical presentation and virological investigation on stool specimens collected during investigation were analysed. RESULTS: Of the specimens analysed, 56% were from males and 76.3% were from children less than 5 years of age. Twenty-four percent of the children received up to 3 doses of OPV, 57% received at least 4 doses while the status of 19% was unknown. Core AFP surveillance indicators were partly met for non-polio AFP rate while the WHO target for stool adequacy and timeliness was exceeded over the period of study. All the cases were classified virologically, however no wild polio was found. Sixty-day follow-up was conducted for 56.3% of cases and 8.6% cases classified as compactible with polio. CONCLUSION: Both laboratory and epidemiological surveillance for AFP were efficient and many WHO targets were met. However, due to the risk of poliovirus importation prior to global eradication, longterm surveillance is required to provide a high degree of confidence in prevention of poliovirus infection in Ghana. Thus, efforts should be made to strengthen regional performance and to follow-up on all AFP cases in order to establish proper diagnoses for the causes of the AFP leading to proper care.

HIV-1 drug-resistance surveillance among treatment-experienced and -naïve patients after the implementation of antiretroviral therapy in Ghana.

BACKGROUND: Limited HIV-1 drug-resistance surveillance has been carried out in Ghana since the implementation of antiretroviral therapy (ART). This study sought to provide data on the profile of HIV-1 drug resistance in ART-experienced and newly diagnosed individuals in Ghana. METHODS: Samples were collected from 101 HIV-1-infected patients (32 ART-experienced cases with virological failure and 69 newly diagnosed ART-naïve cases, including 11 children), in Koforidua, Eastern region of Ghana, from February 2009 to January 2010. The pol gene sequences were analyzed by in-house HIV-1 drug-resistance testing. RESULTS: The most prevalent HIV-1 subtype was CRF02_AG (66.3%, 67/101) followed by unique recombinant forms (25.7%, 26/101). Among 31 ART-experienced adults, 22 (71.0%) possessed at least one drug-resistance mutation, and 14 (45.2%) had two-class-resistance to nucleoside and non-nucleoside reverse-transcriptase inhibitors used in their first ART regimen. Importantly, the number of accumulated mutations clearly correlated with the duration of ART. The most prevalent mutation was lamivudine-resistance M184V (n = 12, 38.7%) followed by efavirenz/nevirapine-resistance K103N (n = 9, 29.0%), and zidovudine/stavudine-resistance T215Y/F (n = 6, 19.4%). Within the viral protease, the major nelfinavir-resistance mutation L90M was found in one case. No transmitted HIV-1 drug-resistance mutation was found in 59 ART-naïve adults, but K103N and G190S mutations were observed in one ART-naïve child. CONCLUSIONS: Despite expanding accessibility to ART in Eastern Ghana, the prevalence of transmitted HIV-1 drug resistance presently appears to be low. As ART provision with limited options is scaled up nationwide in Ghana, careful monitoring of transmitted HIV-1 drug resistance is necessary.

Inhibition of HIV-1 replication by long-term treatment with a chimeric RNA containing shRNA and TAR decoy RNA.

Combinatorial therapies for the treatment of HIV-1 infection are effective for reducing patient viral loads and slowing the progression to AIDS. Our strategy was based on an anti-HIV-1 shRNA vector system in which HIV-1 vif-shRNA was fused to a decoy TAR RNA (mini-TAR RNA) to generate vif-shRNA-decoy TAR RNA under the control of the human U6 Pol III promoter. Upon expression in human cells, the RNA molecule was cleaved into its component parts, which inhibited HIV-1 replication in a synergistic manner. This chimeric RNA expressed a dual RNA moiety and greatly enhanced the inhibition of HIV-1 replication under the production of resistant virus by short interference RNA (siRNA) in long-term culture assays. We suggest that this technique provides a practical basis for the application of siRNA-based gene therapy in the treatment of HIV/AIDS.

Effective inhibition of HIV-1 replication in cultured cells by external guide sequences and ribonuclease P.

We examined the suppressive effect of HIV-1 RNA gene cleavage on HIV-1 expression, using the catalytic RNA subunit RNase P and the 3'-half tRNA(Try) [external guide sequence (EGS)] in cultured cells. HIV-1 expression was inhibited by the tRNA(met)-EGS-U5 and U6-EGS-U5 from the tRNA(met) and U6 promoters, respectively. There was no difference in the inhibitory effects on HIV-1 expression between the tRNA(met) and U6 promoters.