This article summarizes the status of environmental surveillance (ES) used by the Global Polio Eradication Initiative, provides the rationale for ES, gives examples of ES methods and findings, and summarizes how these data are used to achieve poliovirus eradication. ES complements clinical acute flaccid paralysis (AFP) surveillance for possible polio cases. ES detects poliovirus circulation in environmental sewage and is used to monitor transmission in communities. If detected, the genetic sequences of polioviruses isolated from ES are compared with those of isolates from clinical cases to evaluate the relationships among viruses. To evaluate poliovirus transmission, ES programs must be developed in a manner that is sensitive, with sufficiently frequent sampling, appropriate isolation methods, and specifically targeted sampling sites in locations at highest risk for poliovirus transmission. After poliovirus ceased to be detected in human cases, ES documented the absence of endemic WPV transmission and detected imported WPV. ES provides valuable information, particularly in high-density populations where AFP surveillance is of poor quality, persistent virus circulation is suspected, or frequent virus reintroduction is perceived. Given the benefits of ES, GPEI plans to continue and expand ES as part of its strategic plan and as a supplement to AFP surveillance.

No abstract

BackgroundCancer is a leading cause of death world-wide, with approximately 17.5 million new cases and 8.7 million cancer related deaths in 2015. The problems of poor selectivity and severe side effects of the available anticancer drugs, have demanded the need for the development of safer and more effective chemotherapeutic agents. The present study was aimed at determining the cytotoxicities of 31 medicinal plants extracts, used in Nigerian ethnomedicine for the treatment of cancer.MethodsThe plant extracts were screened for cytotoxicity, using the brine shrimp lethality assay (BSLA) and MTT cytotoxicity assay. Rhabdomyosarcoma (RD) cell line, normal Vero cell line and the normal prostate (PNT2) cell line were used for the MTT assay, while Artemia salina nauplii was used for the BSLA. The phytochemical composition of the active plant extracts was determined by high performance liquid chromatography (HPLC) analysis.ResultsThe extract of Eluesine indica (L.) Gaertn (Poaceae), with a LC50 value of 76.3 μg/mL, had the highest cytotoxicity on the brine shrimp larvae compared to cyclophosphamide (LC50 = 101.3 μg/mL). Two plants extracts, Macaranga barteri Mull. Arg. (Euphorbiaceae) and Calliandra portoricensis (Jacq.) Benth (Leguminosae) exhibited significant cytotoxic activity against the RD cell line and had comparable lethal activity on the brine shrimps. Further cytotoxic investigation showed that the dichloromethane fraction of Macaranga barteri (DMB) and the ethyl acetate fraction of Calliandra portoricensis (ECP), exhibited approximately 6-fold and 4-fold activity, respectively, compared to cyclophosphamide on RD cell line. Determination of selective index (SI) using Vero and PNT2 cell line indicated that DMB and ECP displayed a high degree of selectivity against the cancer cell under investigation. HPLC analysis showed that 3,5dicaffeoylquinic acid, acteoside, kampferol-7-O-glucoside and bastadin 11 were the major components of DMB while the major components of ECP were neurolenin B, nigrosporolide and trans-geranic acid.ConclusionThe results demonstrate the cytotoxicity of Macaranga barteri and Calliandra portoricensis extracts, which are used in Nigerian folklore for cancer treatment.

BackgroundEchoviruses, a serotype of enteroviruses, infect millions of people globally and there is no specific drug treatment or vaccine available for its management. The screening of medicinal plants used locally for the treatment of infectious diseases, can provide a reliable option in the discovery of potent therapeutic compounds. This study was carried out to investigate the antiviral activities of 27 medicinal plant extracts, belonging to 26 different plant species, selected from Nigerian ethnobotany, against echovirus 7, 13 and 19 serotypes (E7, E13 and E19, respectively).MethodsThe plants were macerated in methanol and the cytotoxicities of the crude extracts were evaluated on the rhabdomyosarcoma cell line using the MTT assay. The antiviral activity of the plant extracts and fractions against echoviruses (E7, E13, and E19) was determined using the neutralisation assay, an assay that measures the inhibition of cytopathic effect on cell culture.ResultsThe crude extract of Macaranga barteri leaves had the highest cytotoxicity with CC50 value of 0.27 μg/mL. This was followed by Crinum jagus (9.88 μg/mL) and Terminalia ivorensis (12.14 μg/mL). The antiviral screening showed that ten out of the 27 crude plant extracts tested were active on E7 and E19, inhibiting the cytopathic effect of the virus in tissue culture. None of the extracts inhibited the cytopathic effect caused by E13 serotype. Amongst the active plant extracts, the methanol extract of M. barteri leaves had the highest antiviral activity on both E7 and E9 with IC50 values of 0.028 and 0.0017 ng/mL, respectively, followed by the Ageratum conyzoides extract (0.208 μg/mL, E7; 0.006 μg/mL, E19) and Mondia whitei extract (0.038 μg/mL, E7; 0.005 μg/mL, E19). Amongst the fractions of M. barteri, the DCM fraction was most the active and selective on E7 (IC50 = 0.0075 ng/mL; SI = 19,896.54) and E19 (IC50 = 0.0175 ng/mL; SI = 8581.24).ConclusionOur research has demonstrated that Macaranga barteri extracts has potent antiviral activity against echoviruses E7 and E19, and our findings suggest that this extract may have potential as a therapeutic agent in the treatment of enteroviral infections.

Between 2005 and 2011, 23 lineages of circulating vaccine-derived polioviruses (cVDPVs) were detected in Nigeria with nonstructural region (NSR) of non-polio enterovirus C (NPEV-C) origin. However, no information exists on NPEV-C strains recombining with oral poliovirus type 2 vaccine strains (OPV2) to make type 2 cVDPVs (cVDPV2s) in Nigeria. This study was therefore designed to investigate the probable contribution of NPEV-Cs recently isolated in the region to the emergence of cVDPV2s. Eleven enterovirus C (EV-C) strains (8 NPEV-Cs and 3 PV2s) previously isolated by the authors were analysed in this study. All 11 isolates were assayed for cell-line-dependent growth restriction in four cell lines (LLC-MK2, MCF-7, RD and L20B). Subsequently, the isolates were subjected to RT-PCR specific for VP1 and 3Dpol/3'-UTR of EV-C. All PCR products were sequenced, and phylogenetic analysis was performed. All eight NPEV-Cs replicated exclusively in the MCF-7 cell line, while the three PV2s replicated in all four cell lines. The eight NPEV-Cs were identified as CVA13 (7 isolates) and CVA20 (1 isolate) by VP1 analysis, while all 11 isolates were confirmed to be EV-Cs by 3Dpol/3'-UTR analysis. In addition, phylogeny violations suggested that some cVDPVs might have recombined with common ancestors of the NPEV-Cs described in this study. This was confirmed by the scatter plot of divergence in VP1 against that of 3Dpol/3'-UTR sequences for pairs of isolates. The results of this study showed that the NSR of unknown origin found in cVDPVs from the region might have come from NPEV-Cs (e.g., CVA13 and CVA20) circulating in Nigeria.