16 - Assessment of Efficacy and Effectiveness of Antiseptic Mouthwash Products against Oral Microbiota

Mouthwashes help prevent dental caries, gum disease (such as gingivitis), slow down the buildup of plaque (biofilms formed by buccal microbiota) and help fight bad breath (halitosis). These antibacterial products kill bacteria, or hinder their reproduction. Some antiseptic products inhibit growth and reproduction of many microorganisms, including bacteria, as well as fungi, protozoa, and viruses. Mouthwashes that kill or reduce bacterial load in the buccal cavity can reduce the production of sulfur compounds that can cause bad breath. Common ingredients in mouthwashes include cetylpyridinium chloride (CPC), zinc chloride, alcohol and chlorhexidine which can neutralize sulfur compounds as well as kill bacteria. Our main objective in this project is to assess the efficacy and effectiveness of different mouthwash brands with a view to give scientifically sound advice people on the best products for use. Our goal for this research is to test commonly used mouthwash brands. Our methods involve culturing of mixed culture of known microbes (and at a later stage from our own mouths when we get IRB approval), streaking these out onto Petri agar plates to isolate pure cultures, characterizing the isolates and testing the efficacy of the mouthwashes against the isolates. Isolates from each subject are kept on slants of agar medium as pure stocks from which we can further characterize the isolates and how they are affected by the detergents. Spread plates inoculated with comparable microbial densities, based on optical density as measured by the spectrophotometer, will be used to assess the efficacy of individual mouthwash brands on the isolates. Efficacy will be determined based on the size of zone of growth inhibition around blank antibiotic discs soaked in the mouth wash brands under study. Mouthwash brands with the greatest diameters will be considered most efficacious. We will also characterize whether the mouth washes are simply bacteriostatic or bactericidal

#15 - Assessing the presence of Wolbachia in the mosquito populations of Northeast Georgia, USA

Wolbachia, a Gram-negative bacterium that infects mosquitoes along with other arthropods, can suppress the spread of microfilaria through reducing the populations of mosquitoes that carry the heartworms. Historically, research has been conducted to use in the prevention of infections from parasites or viruses like Zika or yellow fever. It is important to understand ways of preventing the various infections from occurring not only by host prevention but through vector prevention or suppression. In the summer of 2018, a total of thirty-five adult female mosquitoes were collected in Oakwood, Georgia at the University of North Georgia in two locations between May 29, 2018 through August 10, 2018 to evaluate for microfilaria and Wolbachia. Following evaluation for microfilaria, DNA extraction from each mosquito was completed for polymerase chain reaction (PCR) testing to test for Wolbachia presence and absence. Data analysis is being continued at this time. Determining the presence of Wolbachia in our adult female samples could help us better determine ways to control mosquito populations to slow or halt the spread of ultimately fatal diseases, parasites, and viruses that are transmitted through adult female mosquitoes. Research conducted through PCR could lead to larger scale research projects sampling mosquitoes for this high-impact bacterium in the future

Impact of Schistosome Infection on Plasmodium falciparum Malariometric Indices and Immune Correlates in School Age Children in Burma Valley, Zimbabwe

A group of children aged 6–17 years was recruited and followed up for 12 months to study the impact of schistosome infection on malaria parasite prevalence, density, distribution and anemia. Levels of cytokines, malaria specific antibodies in plasma and parasite growth inhibition capacities were assessed. Baseline results suggested an increased prevalence of malaria parasites in children co-infected with schistosomiasis (31%) compared to children infected with malaria only (25%) (p = 0.064). Moreover, children co-infected with schistosomes and malaria had higher sexual stage geometric mean malaria parasite density (189 gametocytes/µl) than children infected with malaria only (73/µl gametocytes) (p = 0.043). In addition, a larger percentage of co-infected children (57%) had gametocytes as observed by microscopy compared to the malaria only infected children (36%) (p = 0.06). There was no difference between the two groups in terms of the prevalence of anemia, which was approximately 64% in both groups (p = 0.9). Plasma from malaria-infected children exhibited higher malaria antibody activity compared to the controls (p = 0.001) but was not different between malaria and schistosome plus malaria infected groups (p = 0.44) and malaria parasite growth inhibition activity at baseline was higher in the malaria-only infected group of children than in the co-infected group though not reaching statistical significance (p = 0.5). Higher prevalence and higher mean gametocyte density in the peripheral blood may have implications in malaria transmission dynamics during co-infection with helminths

Plasmodium yoelii: Adverse outcome of non-lethal P. yoelii malaria during co-infection with Schistosoma mansoni in BALB/c mouse model

Plasmodium yoelii and Schistosoma mansoni co-infections were studied in female BALB/c mice aged 4-6 weeks to determine the effect of time and stage of concomitant infections on malaria disease outcome. Patent S. mansoni infection in BALB/c mice increased malaria peak parasitemia and caused death from an otherwise non-lethal, self-resolving P. yoelii malaria infection. Exacerbation of malaria parasitemia occurred during both pre-patent and patent S. mansoni infection resulting in a delay of 4-8 days in malaria parasite resolution in co-infected mice. Praziquantel administered to mice with patent schistosome infection protected from fatal outcome during co-infection. However, this treatment did not completely clear the worm infestation, nor did it reduce the peak malaria parasitemia reached, which was nonetheless resolved completely. Hepatosplenomegaly was more marked in schistosome and malaria co-infected mice compared to either infection separately. The results suggest a complex relationship between schistosome co-infection and malaria disease outcome in which the timing of malaria infection in relation to schistosome acquisition is critical to disease outcome and pathology. © 2009 Elsevier Inc. All rights reserved

Impact of schistosome infection on Plasmodium falciparum Malariometric indices and immune correlates in school age children in Burma Valley, Zimbabwe.

A group of children aged 6-17 years was recruited and followed up for 12 months to study the impact of schistosome infection on malaria parasite prevalence, density, distribution and anemia. Levels of cytokines, malaria specific antibodies in plasma and parasite growth inhibition capacities were assessed. Baseline results suggested an increased prevalence of malaria parasites in children co-infected with schistosomiasis (31%) compared to children infected with malaria only (25%) (p = 0.064). Moreover, children co-infected with schistosomes and malaria had higher sexual stage geometric mean malaria parasite density (189 gametocytes/µl) than children infected with malaria only (73/µl gametocytes) (p = 0.043). In addition, a larger percentage of co-infected children (57%) had gametocytes as observed by microscopy compared to the malaria only infected children (36%) (p = 0.06). There was no difference between the two groups in terms of the prevalence of anemia, which was approximately 64% in both groups (p = 0.9). Plasma from malaria-infected children exhibited higher malaria antibody activity compared to the controls (p = 0.001) but was not different between malaria and schistosome plus malaria infected groups (p = 0.44) and malaria parasite growth inhibition activity at baseline was higher in the malaria-only infected group of children than in the co-infected group though not reaching statistical significance (p = 0.5). Higher prevalence and higher mean gametocyte density in the peripheral blood may have implications in malaria transmission dynamics during co-infection with helminths

A chemiluminescent-western blot assay for quantitative detection of Plasmodium falciparum circumsporozoite protein

Highly sensitive and reliable assays based on the quantitation of immunologically relevant component(s) in recombinant or whole parasite-based vaccines would facilitate pre-clinical and clinical phases and the monitoring of malaria vaccine deployment. Here we report a laboratory-grade Western Blot assay for quantitative detection of Plasmodium falciparum circumsporozoite protein (PfCSP) in P. falciparum sporozoite (PfSPZ) and in recombinant (rPfCSP) product. This assay is based on the immuno-reactivity of an anti-P. falciparum CSP monoclonal antibody (mAb 2A10) with the NANP-repeat units on PfCSP. The antigen-antibody complex is detected by reaction with a commercially obtained chemiluminescence-linked Immunodetection system. The linear range for detecting the recombinant P. falciparum CSP (rPfCSP) in this assay is 3-12pg (R2=0.9399). The range for detecting the day 15 salivary-gland PfSPZ is between 0.0625 and 1 parasite (R2=0.9448) and approximately 10.0pg of PfCSP was detected on each sporozoite. The assay was highly reproducible in measuring the PfCSP on PfSPZ. The inter-assay Coefficient of Variation (CV%) was 10.31% while the intra-assay CV% on three different days was 6.05%, 2.03% and 1.42% respectively. These results suggest that this ECL-WB assay is highly sensitive and robust with a low degree of inter-assay and intra-assay variations. To our knowledge, this is the most sensitive immunoassay for the detection of a recombinant or native malarial protein and may have a wider range of applications including the quantification of immunological component(s) in a vaccine formulation, determination of the antigenic integrity in adjuvanted-vaccine and in stability studies. In addition, this assay can be applied to measure the mosquito infectivity in malaria transmission areas and to determine the effects of intervention measures on malaria transmission. © 2013

A chemiluminescent-western blot assay for quantitative detection of Plasmodium falciparum circumsporozoite protein

Highly sensitive and reliable assays based on the quantitation of immunologically relevant component(s) in recombinant or whole parasite-based vaccines would facilitate pre-clinical and clinical phases and the monitoring of malaria vaccine deployment. Here we report a laboratory-grade Western Blot assay for quantitative detection of Plasmodium falciparum circumsporozoite protein (PfCSP) in P. falciparum sporozoite (PfSPZ) and in recombinant (rPfCSP) product. This assay is based on the immuno-reactivity of an anti-P. falciparum CSP monoclonal antibody (mAb 2A10) with the NANP-repeat units on PfCSP. The antigen-antibody complex is detected by reaction with a commercially obtained chemiluminescence-linked Immunodetection system. The linear range for detecting the recombinant P. falciparum CSP (rPfCSP) in this assay is 3-12pg (R2=0.9399). The range for detecting the day 15 salivary-gland PfSPZ is between 0.0625 and 1 parasite (R2=0.9448) and approximately 10.0pg of PfCSP was detected on each sporozoite. The assay was highly reproducible in measuring the PfCSP on PfSPZ. The inter-assay Coefficient of Variation (CV%) was 10.31% while the intra-assay CV% on three different days was 6.05%, 2.03% and 1.42% respectively. These results suggest that this ECL-WB assay is highly sensitive and robust with a low degree of inter-assay and intra-assay variations. To our knowledge, this is the most sensitive immunoassay for the detection of a recombinant or native malarial protein and may have a wider range of applications including the quantification of immunological component(s) in a vaccine formulation, determination of the antigenic integrity in adjuvanted-vaccine and in stability studies. In addition, this assay can be applied to measure the mosquito infectivity in malaria transmission areas and to determine the effects of intervention measures on malaria transmission. © 2013

Mean growth inhibition activity of different groups at different malaria seasons and survey times.

<p>Ability of subjects' plasma samples to inhibit <i>P. falciparum</i> growth from each group at T0 (Fig. 8a), T6 (Fig. 8b) and T12 (Fig. 8c) are shown. The box plots display <i>in vitro</i> percentage growth inhibition activities of <i>P. falciparum</i> by participants' plasma samples (at 10% concentration) after 48 h growth of synchronized W2 culture. The middle horizontal line in each box indicates the median percentage growth inhibition for each diagnostic group, and the box indicates the 25^th and 75^th percentiles. The whisker caps extending from each box indicate the minimum and maximum values. Individual marked points represent a few outlier values. Figure 8d represents mean growth inhibition data for the entire cohort at three transmission seasons (T0, T6, T12).</p

Study Design.

<p>The arrows indicate the different times at which urine, blood and stool samples were obtained from study participants for diagnosis. The malaria seasons at baseline and follow up times are indicated as well as treatment of schistosome infected children with praziquantel (PZQ).</p