Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

What are Viruses?00:50

What are Viruses?

128.1K
Overview
128.1K
Standard Electrode Potentials03:02

Standard Electrode Potentials

50.3K
On comparing the reactivity of silver and lead, it is observed that the two ionic species, Ag+ (aq) and Pb2+ (aq), show a difference in their redox reactivity towards copper: the silver ion undergoes spontaneous reduction, while the lead ion does not. This relative redox activity can be easily quantified in electrochemical cells by a property called cell potential. This property is commonly known as cell voltage in electrochemistry, and it is a measure of the energy which accompanies the charge...
50.3K
Leveling Effect01:29

Leveling Effect

1.4K
In acid-base chemistry, the leveling effect refers to the limitation imposed by the solvent on the strength of acids and bases in solution. When a base stronger than the solvent's conjugate base is used, it deprotonates the solvent until the base is entirely consumed, making it ineffective against weaker acids. Conversely, an acid stronger than the solvent's conjugate acid protonates the solvent until the acid is depleted, rendering it ineffective against weaker bases. Essentially, the...
1.4K
High-Level and Low-Level Awareness01:19

High-Level and Low-Level Awareness

753
Controlled processes in human consciousness represent high-alert mental states where individuals deliberately focus their attention on achieving specific goals. Controlled processes can be seen in situations like mastering new technology, where a person might become so absorbed that they ignore surrounding distractions. Such processes involve selective attention, requiring one to concentrate on particular elements of experience while disregarding others. These are governed by executive...
753
Standard Enthalpy of Formation02:37

Standard Enthalpy of Formation

49.2K
Enthalpy changes are typically tabulated for reactions in which both the reactants and products are at the same conditions. A standard state is a commonly accepted set of conditions used as a reference point for the determination of properties under other different conditions. For chemists, the IUPAC standard state refers to materials under a pressure of 1 bar and solutions at 1 M and does not specify a temperature. Many thermochemical tables list values with a standard state of 1 atm. Because...
49.2K
Measurement: Standard Units03:38

Measurement: Standard Units

79.8K
Every measurement provides three kinds of information: the size or magnitude of the measurement (a number), a standard of comparison for the measurement (a unit), and an indication of the uncertainty of the measurement. While the number and unit are explicitly represented when a quantity is written, the uncertainty is an aspect of the errors in the measurement results.
79.8K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Historical texts as a potential resource for plant-based antiviral agents against SARS-CoV-2: the example of the Receptarium of Burkhard III von Hallwyl from 16th-century Switzerland.

Frontiers in pharmacology·2026
Same author

Seroprevalence of Borrelia burgdorferi sensu lato and incidence of Lyme borreliosis in Switzerland.

Ticks and tick-borne diseases·2025
Same author

Monkeypox virus spreads from cell-to-cell and leads to neuronal death in human neural organoids.

Nature communications·2025
Same author

Targeted Isolation of Coumarins From Sideritis Species Based on Antiviral Screening and Untargeted Metabolomics.

Phytochemical analysis : PCA·2025
Same author

Tick-borne encephalitis virus seroprevalence and infection incidence in Switzerland, 2020-2021.

Scientific reports·2025
Same author

A Global Collaborative Comparison of SARS-CoV-2 Antigenicity Across 15 Laboratories.

Viruses·2025

Related Experiment Video

Updated: Feb 1, 2026

Modeling The Lifecycle Of Ebola Virus Under Biosafety Level 2 Conditions With Virus-like Particles Containing Tetracistronic Minigenomes
10:11

Modeling The Lifecycle Of Ebola Virus Under Biosafety Level 2 Conditions With Virus-like Particles Containing Tetracistronic Minigenomes

Published on: September 27, 2014

37.0K

Standardized focus assay protocol for biosafety level four viruses.

Rahel Ackermann-Gäumann1, Denise Siegrist1, Roland Züst1

  • 1Spiez Laboratory, Federal Office for Civil Protection, Austrasse, 3700, Spiez, Switzerland.

Journal of Virological Methods
|December 5, 2018
PubMed
Summary

A new standardized 24-well plate focus assay simplifies viral titration for biosafety level four pathogens like Zaire ebolavirus and Marburg virus. This precise method offers a straightforward visual readout, enhancing laboratory efficiency.

Keywords:
Crimean Congo hemorrhagic fever virusEbolavirusFocus assayLassa virusMarburg virusTick-borne encephalitis virus

More Related Videos

Production of Pseudotyped Particles to Study Highly Pathogenic Coronaviruses in a Biosafety Level 2 Setting
08:40

Production of Pseudotyped Particles to Study Highly Pathogenic Coronaviruses in a Biosafety Level 2 Setting

Published on: March 1, 2019

59.7K
A Protocol for Analyzing Hepatitis C Virus Replication
13:04

A Protocol for Analyzing Hepatitis C Virus Replication

Published on: June 26, 2014

24.7K

Related Experiment Videos

Last Updated: Feb 1, 2026

Modeling The Lifecycle Of Ebola Virus Under Biosafety Level 2 Conditions With Virus-like Particles Containing Tetracistronic Minigenomes
10:11

Modeling The Lifecycle Of Ebola Virus Under Biosafety Level 2 Conditions With Virus-like Particles Containing Tetracistronic Minigenomes

Published on: September 27, 2014

37.0K
Production of Pseudotyped Particles to Study Highly Pathogenic Coronaviruses in a Biosafety Level 2 Setting
08:40

Production of Pseudotyped Particles to Study Highly Pathogenic Coronaviruses in a Biosafety Level 2 Setting

Published on: March 1, 2019

59.7K
A Protocol for Analyzing Hepatitis C Virus Replication
13:04

A Protocol for Analyzing Hepatitis C Virus Replication

Published on: June 26, 2014

24.7K

Area of Science:

  • Virology
  • Infectious Diseases
  • Biotechnology

Background:

  • Biosafety level four (BSL-4) laboratory practices are complex and time-consuming.
  • Standardized, simple, and accurate protocols are crucial for BSL-4 research.
  • Efficient viral titration methods are essential for diagnostics and research.

Purpose of the Study:

  • To develop and validate a standardized 24-well plate focus assay protocol.
  • To simplify viral titration for multiple high-containment viruses.
  • To improve the efficiency and reproducibility of viral quantification in BSL-4 laboratories.

Main Methods:

  • Application of a standardized 24-well plate focus assay.
  • Titration of Zaire ebolavirus, Marburg virus, Lassa virus, Crimean Congo hemorrhagic fever virus, and tick-borne encephalitis virus.
  • Determination of viral titers via a simple visual readout.

Main Results:

  • The protocol successfully titrated multiple BSL-4 viral agents.
  • High precision was demonstrated with interassay CVs between 0.05-0.21 and intraassay CVs between 0.08-0.23.
  • The assay provides a straightforward visual readout for viral quantification.

Conclusions:

  • The standardized 24-well plate focus assay is a precise and efficient method for titrating various BSL-4 viruses.
  • The protocol's simplicity and reliance on commercially available reagents facilitate its adoption in other laboratories.
  • This assay can enhance workflow efficiency and standardization in high-containment virology.