Endemic Australian arboviruses of human health significance

2018 ◽  
Vol 39 (2) ◽  
pp. 88
Author(s):  
David W Smith
Keyword(s):  
Human Health ◽  
Virus Replication ◽  
Joint Disease ◽  
Urban Populations ◽  
Temperature Conditions ◽  
Virus Activity ◽  
Mosquito Breeding ◽  
Health Significance ◽  
Animal Hosts ◽  
Arbovirus Infection

Each year many thousands of cases of human arbovirus infection are notified within Australia, acquired either within Australia or when travelling overseas1. These cause diseases varying from fever and aches, to debilitating joint disease, to encephalitis and death. The arboviruses endemic to Australia are all maintained in a cycle between mosquitoes (and rarely midges) and a bird or mammalian host2. As such, the virus activity is dependent on rainfall and temperature conditions that are conducive to mosquito breeding, and to virus replication and amplification (Figure 1). Those conditions being met, there have to be suitable amplifying animal hosts nearby, and their absence is one of the factors that protects most of the larger urban populations in Australia. Then, of course, humans have to be exposed to the infected mosquitoes to get disease.

scholarly journals Detection, integration and persistence of aeromonads in water distribution pipe biofilms

2004 ◽  
Vol 2 (2) ◽  
pp. 83-96 ◽  
Author(s):  
A.-M. Bomo ◽  
M. V. Storey ◽  
N. J. Ashbolt
Keyword(s):  
Human Health ◽  
Water Distribution ◽  
Water System ◽  
Water Systems ◽  
Biofilm Reactor ◽  
Recycled Water ◽  
Decay Kinetics ◽  
Aeromonas Caviae ◽  
Health Significance

The occurrence of Aeromonas spp. within biofilms formed on stainless steel (SS), unplasticized polyvinyl chloride (uPVC) and glass (GL) substrata was investigated in modified Robbins Devices (MRD) in potable (MRD-p) and recycled (MRD-r) water systems, a Biofilm Reactor™ (BR) and a laboratory-scale pipe loop (PL) receiving simulated recycled wastewater. No aeromonads were isolated from the MRD-p whereas 3–10% of SS and uPVC coupons (mean 3.85 CFU cm−2 and 12.8 CFU cm−2, respectively) were aeromonad-positive in the MRD-r. Aeromonads were isolated from six SS coupons (67%) (mean 63.4 CFU cm−2) and nine uPVC coupons (100%) (mean 6.50×102 CFU cm−2) in the BR™ fed with recycled water and from all coupons (100%) in the simulated recycled water system (PL). Mean numbers of aeromonads on GL and SS coupons were 5.83×102 CFU cm−2 and 8.73×102 CFU cm−2, respectively. No isolate was of known human health significance (i.e. Aeromonas caviae, A. hydrophila or A. veronii), though they were confirmed as Aeromonas spp. by PCR and fluorescence in situ hybridization (FISH). Challenging the PL biofilms with a slug dose of A. hydrophila (ATCC 14715) showed that biofilm in the PL accumulated in the order of 103–104A. hydrophila cm−2, the number of which decreased over time, though could not be explained in terms of conventional 1st order decay kinetics. A sub-population of FISH-positive A. hydrophila became established within the biofilm, thereby demonstrating their ability to incorporate and persist in biofilms formed within distribution pipe systems. A similar observation was not made for culturable aeromonads, though the exact human health significance of this remains unknown. These findings, however, further question the adequacy of culture-based techniques and their often anomalous discrepancy with direct techniques for the enumeration of bacterial pathogens in environmental samples.

Analytical Methodology and the Interface with Animal Drug Approval

1978 ◽  
Vol 61 (5) ◽  
pp. 1183-1191
Author(s):  
Maryln K Perez
Keyword(s):  
Systematic Review ◽  
Human Health ◽  
Safety Data ◽  
Drug Approval ◽  
Analytical Methodology ◽  
Health Significance ◽  
A Priority

Abstract FDA is engaged in a systematic review of approved animal drugs to determine whether upgrading of safety data is required to provide continuing assurance that the approved uses for these drugs are safe. These reviews will be undertaken on the basis of a priority of anticipated human health significance.

scholarly journals The citrus flavanone naringenin impairs dengue virus replication in human cells

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Sandra Frabasile ◽  
Andrea Cristine Koishi ◽  
Diogo Kuczera ◽  
Guilherme Ferreira Silveira ◽  
Waldiceu Aparecido Verri ◽  
...  
Keyword(s):  
Dengue Virus ◽  
Virus Replication ◽  
Fruits And Vegetables ◽  
Suitable Candidate ◽  
Tropical Regions ◽  
Virus Activity ◽  
Dengue Virus Serotypes ◽  
Medicinal Properties ◽  
Virus Exposure ◽  
Significant Health

Abstract Dengue is one of the most significant health problems in tropical and sub-tropical regions throughout the world. Nearly 390 million cases are reported each year. Although a vaccine was recently approved in certain countries, an anti-dengue virus drug is still needed. Fruits and vegetables may be sources of compounds with medicinal properties, such as flavonoids. This study demonstrates the anti-dengue virus activity of the citrus flavanone naringenin, a class of flavonoid. Naringenin prevented infection with four dengue virus serotypes in Huh7.5 cells. Additionally, experiments employing subgenomic RepDV-1 and RepDV-3 replicon systems confirmed the ability of naringenin to inhibit dengue virus replication. Antiviral activity was observed even when naringenin was used to treat Huh7.5 cells 24 h after dengue virus exposure. Finally, naringenin anti-dengue virus activity was demonstrated in primary human monocytes infected with dengue virus sertoype-4, supporting the potential use of naringenin to control dengue virus replication. In conclusion, naringenin is a suitable candidate molecule for the development of specific dengue virus treatments.

scholarly journals Cycluridine: A novel antiviral effective against flaviviruses

2017 ◽  
Vol 25 (2) ◽  
pp. 58-67 ◽  
Author(s):  
Angel S Galabov ◽  
Lucia Mukova ◽  
Yuriy P Abashev ◽  
Lilia Wassilewa ◽  
Petko Tzvetkov ◽  
...  
Keyword(s):  
Protective Effect ◽  
Virus Replication ◽  
Bovine Viral Diarrhoea Virus ◽  
Inhibitory Effect ◽  
Encephalitis Virus ◽  
Sensitive Period ◽  
Bovine Viral Diarrhoea ◽  
Virus Activity ◽  
Diarrhoea Virus ◽  
State Of Research

This review describes the contemporary state of research for antivirals effective against flaviviruses, especially focusing on inhibitors of the pestivirus causative agent of bovine viral diarrhoea virus. We highlight cycluridine, an originally synthesized Mannich’s base [a tetrahydro-2(1H)-pyrimidinones derivative], as a highly effective antiviral possessing a strong inhibitory effect on bovine viral diarrhoea virus replication. Cycluridine was active against replication of a wide variety of bovine viral diarrhoea virus strains in cell cultures. The drug-sensitive period in the bovine viral diarrhoea virus replication cycle included the latent period and the exponential phase; a 90-min delay in the peak of viral RNA synthesis was observed. Cycluridine administered orally manifested a pronounced protective effect in calves with natural mucosal disease/viral diarrhoea and calves experimentally infected with bovine viral diarrhoea virus. Its magnitude of activity and selectivity places cycluridine in the lead among all known substances with anti- bovine viral diarrhoea virus activity. Additionally, cycluridine applied subcutaneously showed anti-tick-born encephalitis virus activity, manifesting a marked protective effect in mice infected with tick-born encephalitis virus. Cycluridine could be a prospective antiviral in veterinary and medical practice for the treatment of bovine viral diarrhoea virus and other flavivirus infections.

Prevalence and antimicrobial resistance of vibrios of human health significance in inland saline aquaculture areas

2018 ◽  
Vol 49 (6) ◽  
pp. 2166-2174 ◽  
Author(s):  
Balwinder Singh ◽  
Anuj Tyagi ◽  
Naveen K Billekallu Thammegowda ◽  
Meera D Ansal
Keyword(s):  
Antimicrobial Resistance ◽  
Human Health ◽  
Health Significance

scholarly journals Temperature alters gene expression in mosquitoes during arbovirus infection

2020 ◽  
Author(s):  
BMC Randika Wimalasiri-Yapa ◽  
Roberto A. Barrero ◽  
Liesel Stassen ◽  
Louise M. Hafner ◽  
Elizabeth A. McGraw ◽  
...  
Keyword(s):  
Gene Expression ◽  
Virus Replication ◽  
Post Infection ◽  
Expression Profiles ◽  
Significant Proportion ◽  
Early Time ◽  
Rnai Pathway ◽  
Ambient Temperatures ◽  
Higher Temperature ◽  
Arbovirus Infection

ABSTRACTArthropod-borne viruses (arboviruses) such as dengue, Zika and chikungunya constitute a significant proportion of the global disease burden. The principal vector of these pathogens is the mosquito Aedes (Ae.) aegypti, and its ability to transmit virus to a human host is influenced by environmental factors such as temperature. However, exactly how ambient temperature influences virus replication within mosquitoes remains poorly elucidated, particularly at the molecular level. Here, we use chikungunya virus (CHIKV) as a model to understand how the host mosquito transcriptome responds to arbovirus infection under different ambient temperatures. We exposed CHIKV-infected mosquitoes to 18 °C, 28 °C and 32 °C, and found higher temperature correlated with higher virus replication levels, particularly at early time points post-infection. Lower ambient temperatures resulted in reduced virus replication levels. Using RNAseq, we found that temperature significantly altered gene expression levels in mosquitoes, particularly components of the immune response. The highest number of significantly differentially expressed genes in response to CHIKV was observed at 28 °C, with a markedly more muted effect observed at either lower (18 °C) or higher (32 °C) temperatures. At the higher temperature, the expression of many classical immune genes, including Dicer-2 in the RNAi pathway, was not substantially altered in response to CHIKV. Upregulation of Toll, IMD and JAK-STAT pathways was only observed at 28 °C. Time post infection also led to substantially different gene expression profiles, and this effect varied depending upon the which temperature mosquitoes were exposed to. Taken together, our data indicate temperature significantly modulates mosquito gene expression in response to infection, potentially leading to impairment of immune defences at higher ambient temperatures.

scholarly journals Prevalence of intestinal parasites in a range of animal hosts and potential implications to animal and human health in Edo, Nigeria

2022 ◽  
Vol 23 ◽  
Author(s):  
Collins Inegbenosun ◽  
Clement Isaac ◽  
Felicitas Anika ◽  
Philip Aihebholoria
Keyword(s):  
Human Health ◽  
Intestinal Parasites ◽  
Animal Hosts
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