Research articles should generally not exceed 25 typewritten pages and should be divided into Summary (on a separate sheet and not exceeding 200 words, followed by 3-6 keywords). Introduction, Materials and Methods, Results, Discussion, Acknowledgements and References.
Short communications, approx. 12 typewritten pages, with a Summary and keywords but without section headings.
Book reviews or meeting reports will be published following invitation from, or by authors first contacting, the Editor-in-Chief, Arie J. Zuckerman:

Arie J. Zuckerman
Email: j.v.meth@medsch.ucl.ac.uk
Tel: +44 (0) 20 7830 2579
Fax: +44 (0) 20 7830 2070

Please note there are different Instructions to Authors for VIROLOGY PROTOCOLS. These are included at the end of this Guide for Authors. It is hoped that this list will be useful during the final checking of an article prior to sending it to the journal's Editor for review. Please consult this Guide for Authors for further details of any item.
Ensure that the following items are present:
One Author designated as corresponding Author:
• E-mail address
• Full postal address
• Telephone and fax numbers
• All necessary files have been uploaded
• Keywords
• All figure captions
• All tables (including title, description, footnotes)

Further considerations
• Manuscript has been "spellchecked"
• References are in the correct format for this journal
• All references mentioned in the Reference list are cited in the text, and vice versa
• Permission has been obtained for use of copyrighted material from other sources (including the Web)
• Colour figures are clearly marked as being intended for colour reproduction on the Web (free of charge) and in print or to be reproduced in colour on the Web (free of charge) and in black-and-white in print
• If only colour on the Web is required, black and white versions of the figures are also supplied for printing purposes
For any further information please contact the Author Support Department at authorsupport@elsevier.com
It is essential to give a fax number and e-mail address when submitting a manuscript. Articles must be written in good English.

Submission of an article implies that the work described has not been published previously (except in the form of an abstract or as part of a published lecture or academic thesis), that it is not under consideration for publication elsewhere, that its publication is approved by all authors and tacitly or explicitly by the responsible authorities where the work was carried out, and that, if accepted, it will not be published elsewhere in the same form, in English or in any other language, without the written consent of the Publisher.

Upon acceptance of an article, Authors will be asked to transfer copyright (for more information on copyright see http://www.elsevier.com/copyright). This transfer will ensure the widest possible dissemination of information. A letter will be sent to the corresponding Author confirming receipt of the manuscript. A form facilitating transfer of copyright will be provided.
If excerpts from other copyrighted works are included, the Author(s) must obtain written permission from the copyright owners and credit the source(s) in the article. Elsevier has preprinted forms for use by Authors in these cases: contact Elsevier's Rights Department, Oxford, UK: phone (+44) 1865 843830, fax (+44) 1865 853333, e-mail permissions@elsevier.com. Requests may also be completed on-line via the Elsevier homepage ( http://www.elsevier.com/locate/permissions)).

US National Institutes of Health (NIH) voluntary posting(" Public Access") policy
Elsevier facilitates author response to the NIH voluntary posting request (referred to as the NIH "Public Access Policy", see http://www.nih.gov/about/publicaccess/index.htm) by posting the peer-reviewed author's manuscript directly to PubMed Central on request from the author, 12 months after formal publication. Upon notification from Elsevier of acceptance, we will ask you to confirm via e-mail (by e-mailing us at NIHauthorrequest@elsevier.com) that your work has received NIH funding and that you intend to respond to the NIH policy request, along with your NIH award number to facilitate processing. Upon such confirmation, Elsevier will submit to PubMed Central on your behalf a version of your manuscript that will include peer-review comments, for posting 12 months after formal publication. This will ensure that you will have responded fully to the NIH request policy. There will be no need for you to post your manuscript directly with PubMed Central, and any such posting is prohibited.

Ethical Policy: human subjects and animals
The research described in papers submitted to the Journal of Virological Methods that involve the use of human beings, including healthy volunteers, must adhere to the principles of the Declaration of Helsinki as well as to Title 45, U.S. Code of Federal Regulations, Part 46, Protection of Human Subjects, Revised November 13, 2001, effective December 13, 2001. Research involving animals must adhere to the American Physiological Society's Guiding Principles in the Care and Use of Animals. All investigations involving humans or animals that are reported in the journal must be conducted in conformity with these principles, and that a statement of protocol approval from an * IRB or * * IACUC or equivalent is included in the methods section of the paper. Manuscripts reporting the results of experiments on human subjects, including healthy volunteers, must include a statement that informed consent was obtained.

* IRB = Institutional Review Board
* * IACUC = Institutional Animal Care and Use Committee

Authors' rights
As an author you (or your employer or institution) may do the following:
- make copies (print or electronic) of the article for your own personal use, including for your own classroom teaching use
- make copies and distribute such copies (including through e-mail) of the article to research colleagues, for the personal use by such colleagues (but not commercially or systematically, e.g., via an e-mail list or list server)
- post a pre-print version of the article on Internet websites including electronic pre-print servers, and to retain indefinitely such version on such servers or sites
- post a revised personal version of the final text of the article (to reflect changes made in the peer review and editing process) on your personal or institutional website or server, with a link to the journal homepage (on http://www.elsevier.com)
- present the article at a meeting or conference and to distribute copies of the article to the delegates attending such a meeting
- for your employer, if the article is a 'work for hire', made within the scope of your employment, your employer may use all or part of the information in the article for other intra-company use (e.g., training)
- retain patent and trademark rights and rights to any processes or procedure described in the article
- include the article in full or in part in a thesis or dissertation (provided that this is not to be published commercially)
- use the article or any part thereof in a printed compilation of your works, such as collected writings or lecture notes (subsequent to publication of your article in the journal)
- prepare other derivative works, to extend the article into book-length form, or to otherwise re-use portions or excerpts in other works, with full acknowledgement of its original publication in the journal

Should Authors be requested by the Editor to revise the text, the revised version should be submitted within six months. After this period, the article will be regarded as a new submission.

Online submission to the journal prior to acceptance

Submission to this journal proceeds totally online. Use the following guidelines to prepare your article. Via the home page of this journal ( http://www.elsevier.com/journals) you will be guided stepwise through the creation and uploading of the various files. The system automatically converts source files to a single Adobe Acrobat PDF version of the article, which is used in the peer-review process. Please note that even though manuscript source files are converted to PDF at submission for the review process, these source files are needed for further processing after acceptance. All correspondence, including notification of the Editor's decision and requests for revision, takes place by e-mail and via the Author's homepage, removing the need for a hard-copy paper trail.

The above represents a very brief outline of this form of submission. It can be advantageous to print this "Guide for Authors" section from the site for reference in the subsequent stages of article preparation.

Electronic format requirements

General points

We accept most wordprocessing formats, but Word or WordPerfect is preferred. Always keep a backup copy of the electronic file for reference and safety. Save your files using the default extension of the program used.

Wordprocessor documents
It is important that the file be saved in the native format of the wordprocessor used. The text should be in single-column format. Keep the layout of the text as simple as possible. Most formatting codes will be removed and replaced on processing the article. In particular, do not use the wordprocessor's options to justify text or to hyphenate words. However, do use bold face, italics, subscripts, superscripts etc. Do not embed "graphically designed" equations or tables, but prepare these using the wordprocessor's facility. When preparing tables, if you are using a table grid, use only one grid for each individual table and not a grid for each row. If no grid is used, use tabs, not spaces, to align columns. The electronic text should be prepared in a way very similar to that of conventional manuscripts (see also the Guide to Publishing with Elsevier: http://www.elsevier.com). Do not import the figures into the text file but, instead, indicate their approximate locations directly in the electronic text and on the manuscript. See also the section on Preparation of electronic illustrations.

To avoid unnecessary errors you are strongly advised to use the "spellchecker" function of your wordprocessor.

Please do not split the article into separate files (titlepage as one file, text as another, etc.). Ensure that the letter "l" and digit "1" (also letter 'O' and digit '0') have been used properly, and structure your article (tabs, indents, etc.)consistently. Characters not available on your wordprocessor (Greek letters, mathematical symbols, etc.) should not be left open but indicated by a unique code (e.g., gralpha, @, #, etc.,for the Greek letter ). Such codes should be used consistently throughout the entire text. Please make a list of such codes and provide a key. Do not allow your wordprocessor to introduce word splits and do not use a "justified" layout. Please adhere strictly to the general instructions on style/arrangement and, in particular, the reference style of the journal.
Presentation of manuscript

Please write your text in good English (American or British usage is accepted, but not a mixture of these). Italics are not to be used for expressions of Latin origin, for example, in vivo, et al., per se. Use decimal points (not commas); use a space for thousands (10 000 and above).

It is essential that authors whose first language is not English should arrange, for the sake of clarity and in their own interest, for manuscripts to be written in idiomatic English before submission. The pronouns "we" and "our" should not be used in a scientific communication. Split-infinitives should be avoided. Do not use acronyms excessively and unusual abbreviations must not be used.

Authors who require information about language editing and copyediting services pre- and post-submission, please visit http://www.elsevier.com/locate/languagepolising or our customer support site at http://epsupport.elsevier.com. Please note Elsevier neither endorses nor takes responsibility for any products, goods or services offered by outside vendors through our services or in any advertising. For more information please refer to our Terms and Conditions http://www.elsevier.com/termsandconditions.

Provide the following data on the title page (in the order given).

Title.
Concise and informative. Titles are often used in information-retrieval systems. Avoid abbreviations and formulae where possible.

Author names and affiliations.
Where the family name may be ambiguous (e.g., a double name), please indicate this clearly. Present the Authors' affiliation addresses (where the actual work was done) below the names. Indicate all affiliations with a lower-case superscript letter immediately after the Author's name and in front of the appropriate address. Provide the full postal address of each affiliation, including the country name, and, if available, the e-mail address of each Author.

Corresponding Author.
Clearly indicate who is willing to handle correspondence at all stages of refereeing and publication, also post-publication. Ensure that telephone and fax numbers (with country and area code) are provided in addition to the e-mail address and the complete postal address.

Present/permanent address.
If an Author has moved since the work described in the article was done, or was visiting at the time, a "Present address"' (or "Permanent address") may be indicated as a footnote to that Author's name. The address at which the Author actually did the work must be retained as the main, affiliation address. Superscript Arabic numerals are used for such footnotes.

Abstract
A concise and factual abstract is required (maximum length 200 words). The abstract should state briefly the purpose of the research, the principal results and major conclusions. An abstract is often presented separate from the article, so it must be able to stand alone.

References should therefore be avoided, but if essential, they must be cited in full, without reference to the reference list.

The use of abbreviations is discouraged and only a minimum number of acronyms may be included if they are necessary. Non-standard or uncommon abbreviations should be avoided, but if essential they must be defined at their first mention in the abstract itself.

Keywords.
Immediately after the abstract, provide a maximum of 6 keywords, avoiding general and plural terms and multiple concepts (avoid, for example, "and", "of"). Be sparing with abbreviations: only abbreviations firmly established in the field may be eligible. These keywords will be used for indexing purposes.

Abbreviations.
Define abbreviations that are not standard in this field at their first occurrence in the article: in the abstract but also in the main text after it. Ensure consistency of abbreviations throughout the article.

Arrangement of the article

Subdivision of the article.
Divide your article into clearly defined and numbered sections. Subsections should be numbered 1.1 (then 1.1.1, 1.1.2, ?), 1.2, etc. (the abstract is not included in section numbering). Use this numbering also for internal cross-referencing: do not just refer to "the text". Any subsection may be given a brief heading. Each heading should appear on its own separate line.

Introduction.
State the objectives of the work and provide an adequate background, avoiding a detailed literature survey or a summary of the results.

Experimental/Materials and methods.
Provide sufficient detail to allow the work to be reproduced. Methods already published should be indicated by a reference: only relevant modifications should be described.

Results.
Results should be clear and concise.

Discussion.
This should explore the significance of the results of the work, not repeat them.

Conclusions.
The main conclusions of the study may be presented in a short Conclusions section, which may stand alone or form a subsection of a Discussion or Results and Discussion section.

Acknowledgements.
Place acknowledgements, including information on grants received, before the references, in a separate section, and not as a footnote on the title page.

References.
See separate section, below

Figure captions, tables, figures, schemes.
Present these, in this order, at the end of the article. They are described in more detail below. High-resolution graphics files must always be provided separate from the main text file (see Preparation of illustrations).

Footnotes.
Footnotes should be used sparingly. Number them consecutively throughout the article, using superscript Arabic numbers. Many wordprocessors build footnotes into the text, and this feature may be used. Should this not be the case, indicate the position of footnotes in the text and present the footnotes themselves on a separate sheet at the end of the article. Do not include footnotes in the Reference list.

Table footnotes.
Indicate each footnote in a table with a superscript lowercase letter.

Tables.
Number tables consecutively in accordance with their appearance in the text. Place footnotes to tables below the table body and indicate them with superscript lowercase letters. Avoid vertical rules. Be sparing in the use of tables and ensure that the data presented in tables do not duplicate results described elsewhere in the article.

Nomenclature and units.
Follow internationally accepted rules and conventions: use the international system of units (SI). If other quantities are mentioned, give their equivalent in SI.

Virus nomenclature.

Each virus should be identified at least once, preferably in the 'Introduction' or 'Materials and Methods' section, using formal family, genus, and species terms and where possible by using a precise strain designation term as developed by an internationally recognized specialty group or culture collection. Please note that the word type is not used before species designations that include a number. Formal terms used for virus families, genera, and species should be those approved by the International Committee on Taxonomy of Viruses (ICTV):Fauquet, C.M., Mayo, M.A.,Maniloff, J., Desselberger, U., and Ball, L.A.(2005) Virus Taxonomy, Classification and Nomenclature of Viruses. Eighth ICTV Report, Academic Press, an imprint of Elsevier. This volume also includes standard abbreviations for species. Once formal taxonomic names have been given in a paper, vernacular terms may be used.

Formal taxonomic nomenclature
In formal taxonomic usage, the first letters of virus order, family, subfamily, genus and species names are capitalized and the terms are printed in italics. Other words in the species names are not capitalized unless they are proper nouns or parts of nouns, for example West Nile virus. In formal usage, the name of the taxon should precede the term for the taxonomic unit; for example; "the family Paramyxoviridae," "the genus Morbillivirus." The following represent examples of full formal taxonomic terminology:

1. Order Mononegavirales, family Rhabdoviridae, genus Lyssavirus, species Rabies virus.

2. Family Poxviridae, subfamily Chordopoxvirinae, genus Orthopoxvirus, species Vaccinia virus.

3. Family Picornaviridae, genus Enterovirus, species Poliovirus.

4. Family Bunyaviridae, genus Tospovirus, species Tomato spotted wilt virus.

Vernacular Taxonmic Nomenclature

In formal vernacular usage, virus order, family, subfamily, genus and species names are written in lower case Roman script: they are not capitalized, nor are they printed in italics or underlined. In informal usage, the name of the taxon should not include the formal suffix, and the name of the taxon should follow the term for the taxonomic unit; for example "the picornavirus family, the enterovirus genus." One particular source of ambiguity in vernacular nomenclature lies in the common use of the same root terms in formal family, genus or species names. Imprecision stems from not being able to easily identify in vernacular usage which hierarchical level is being cited. For example, the vernacular name "paramyxovirus" might refer to the family Paramyxoviridae, or one species in the genus Respirovirus, such as Human parainfluenza virus 1. The solution in vernacular usage is to avoid "jumping" hierarchical levels and to add taxon identification wherever needed. For example, when citing the taxonomic placement of Human parainfluenza virus 1, taxon identification should always be added: Human Parainfluenza virus 1 is a species in the genus Respirovirus, family Paramyxoviridae. In this example, as is usually the case, adding the information that this virus is also a member of the subfamily Paramyxovirinaeand the order Mononegavirales is unnecessary.

It should be stressed that italics and capital initial letters need be used only if the species name refers to the taxonomic category. When the name refers to viral objects such as virions present in a preparation or seen in an electron micrograph, italics and capital initial letters are not needed and the names are written in lower case Roman script. This also applies when the names are used in adjectival form, for instance tobacco mosaic virus polymerase. The use of italics when referring to the name of a species as a taxonomic entity signals that it has the status of an officially recognized species. The 8th ICTV Report (Fauquet, C.M. et al., 2005, Academic Press, an imprint of Elsevier) should be consulted to ascertain which names have been approved as official species names. When the taxonomic status of a new putative species is uncertain or its position within an established genus has not been clarified, it is considered a tentative species and its name is not written in italics although its initial letter is capitalized.

Origins of bioreagents
The origins of bioreagents should be described adequately, including citation of culture collections, companies, or colleagues from whom the bioreagents were obtained. If viruses were collected from nature, the collecting site and procedure should also be properly described. Bioreagents include but are not necessarily limited to virus strains and species, antibodies, and cell lines.

DNA sequences and GenBank Accession numbers.

Many Elsevier journals cite "gene accession numbers" in their running text and footnotes. Gene accession numbers refer to genes or DNA sequences about which further information can be found in the databases at the National Center for Biotechnical Information (NCBI) at the National Library of Medicine. Elsevier Authors wishing to enable other scientists to use the accession numbers cited in their papers via links to these sources, should type this information in the following manner:

For each and every accession number cited in an article, Authors should type the accession number in bold, underlined text. Letters in the accession number should always be capitalised. (See Example below). This combination of letters and format will enable Elsevier's typesetters to recognise the relevant texts as accession numbers and add the required link to GenBank's sequences.

Example: "GenBank accession nos. AI631510 , AI631511 , AI632198 , and BF223228) , a B-cell tumor from a chronic lymphatic leukemia (GenBank accession no. BE675048) , and a T-cell lymphoma (GenBank accession no. AA361117) ".

Authors are encouraged to check accession numbers used very carefully. An error in a letter or number can result in a dead link. In the final version of the printed article, the accession number text will not appear bold or underlined. In the final version of the electronic copy, the accession number text will be linked to the appropriate source in the NCBI databases enabling readers to go directly to that source from the article.

Preparation of supplementary data.
Elsevier accepts electronic supplementary material to support and enhance your scientific research. Supplementary files offer the Author additional possibilities to publish supporting applications, movies, animation sequences, high-resolution images, background datasets, sound clips and more. Supplementary files supplied will be published online alongside the electronic version of your article in Elsevier Web products, including ScienceDirect: http://www.sciencedirect.com. In order to ensure that your submitted material is directly usable, please ensure that data is provided in one of our recommended file formats. Authors should submit the material in electronic format together with the article and supply a concise and descriptive caption for each file. For more detailed instructions please visit our artwork instruction pages at http://www.elsevier.com/artworkinstructions. Responsibility for the accuracy of bibliographic citations lies entirely with the Authors.

Citations in the text:
Please ensure that every reference cited in the text is also present in the reference list (and vice versa). Any references cited in the abstract must be given in full. Unpublished results and personal communications are not recommended in the reference list, but may be mentioned in the text. If these references are included in the reference list they should follow the standard reference style of the journal and should include a substitution of the publication date with either "Unpublished results" or "Personal communication" Citation of a reference as "in press" implies that the item has been accepted for publication and a copy of the title page of the relevant article must be submitted.

Citing and listing of Web references.
As a minimum, the full URL should be given. Any further information, if known (Author names, dates, reference to a source publication, etc.), should also be given. Web references can be listed separately (e.g., after the reference list) under a different heading if desired, or can be included in the reference list.

Text:
All citations in the text should refer to:
1. Single Author: the Author's name (without initials, unless there is ambiguity) and the year of publication;
2. Two Authors: both Authors' names and the year of publication;
3. Three or more Authors: first Author's name followed by "et al." and the year of publication.
Citations may be made directly (or parenthetically). Groups of references should be listed first alphabetically, then chronologically.
Examples: "as demonstrated (Allan, 1996a, 1996b, 1999; Allan and Jones, 1995). Kramer et al. (2000) have recently shown ...."
List: References should be arranged first alphabetically and then further sorted chronologically if necessary. More than one reference from the same Author(s) in the same year must be identified by the letters "a", "b", "c", etc., placed after the year of publication.
Examples:
Reference to a journal publication:
Van der Geer, J., Hanraads, J.A.J., Lupton, R.A., 2000. The art of writing a scientific article. J. Sci. Commun. 163, 51-59.
Reference to a book:
Strunk Jr., W., White, E.B., 1979. The Elements of Style, third ed. Macmillan, New York.
Reference to a chapter in an edited book:
Mettam, G.R., Adams, L.B., 1999. How to prepare an electronic version of your article, in: Jones, B.S., Smith , R.Z. (Eds.), Introduction to the Electronic Age. E-Publishing Inc., New York, pp. 281-304.

Use of the Digital Object Identifier (DOI)
The digital object identifier (DOI) may be used to cite and link to electronic documents. The DOI consists of a unique alpha-numeric character string which is assigned to a document by the publisher upon the initial electronic publication. The assigned DOI never changes. Therefore, it is an ideal medium for citing a document, particularly 'Articles in press' because they have not yet received their full bibliographic information. The correct format for citing a DOI is shown as follows (example taken from a document in the journal Physics Letters B):
doi:10.1016/j.physletb.2003.10.071

When you use the DOI to create URL hyperlinks to documents on the web, they are guaranteed never to change.

General points
• Make sure you use uniform lettering and sizing of your original artwork.
• Save text in illustrations as "graphics" or enclose the font.
• Only use the following fonts in your illustrations: Arial, Courier, Helvetica, Times, Symbol.
• Number the illustrations according to their sequence in the text.
• Use a logical naming convention for your artwork files.
• Provide all illustrations as separate files and as hardcopy printouts on separate sheets.
• Provide captions to illustrations separately.
• Produce images near to the desired size of the printed version.

A detailed guide on electronic artwork is available on our website:
http://www.elsevier.com/artworkinstructions

You are urged to visit this site; some excerpts from the detailed information are given here.

Formats
Regardless of the application used, when your electronic artwork is finalised, please "save as" or convert the images to one of the following formats (Note the resolution requirements for line drawings, halftones, and line/halftone combinations given below.):
EPS: Vector drawings. Embed the font or save the text as "graphics".
TIFF: Colour or greyscale photographs (halftones): always use a minimum of 300 dpi.
TIFF: Bitmapped line drawings: use a minimum of 1000 dpi.
TIFF: Combinations bitmapped line/half-tone (colour or greyscale): a minimum of 500 dpi is required.
DOC, XLS or PPT: If your electronic artwork is created in any of these Microsoft Office applications please supply "as is".

Please do not:
• Supply embedded graphics in your wordprocessor (spreadsheet, presentation) document;
• Supply files that are optimised for screen use (like GIF, BMP, PICT, WPG); the resolution is too low;
• Supply files that are too low in resolution;
• Submit graphics that are disproportionately large for the content.

Captions
Ensure that each illustration has a caption. Supply captions separately, not attached to the figure. A caption should comprise a brief title (not on the figure itself) and a description of the illustration. Keep text in the illustrations themselves to a minimum but explain all symbols and abbreviations used.

Line drawings
The lettering and symbols, as well as other details, should have proportionate dimensions, so as not to become illegible or unclear after possible reduction; in general, the figures should be designed for a reduction factor of two to three. The degree of reduction will be determined by the Publisher. Illustrations will not be enlarged. Consider the page format of the journal when designing the illustrations.
Do not use any type of shading on computer-generated illustrations.

Photographs (halftones)
Remove non-essential areas of a photograph. Do not mount photographs unless they form part of a composite figure. Where necessary, insert a scale bar in the illustration (not below it), as opposed to giving a magnification factor in the caption.
Note that photocopies of photographs are not acceptable.

Colour Illustrations
Please make sure that artwork files are in an acceptable format (TIFF, EPS or MS Office files) and with the correct resolution. If, together with your accepted article, you submit usable colour figures then Elsevier will ensure, at no additional charge, that these figures will appear in colour on the Web (e.g., ScienceDirect and other sites) regardless of whether or not these illustrations are reproduced in colour in the printed version. For colour reproduction in print, you will receive information regarding the costs from Elsevier after receipt of your accepted article. Please indicate your preference for colour in print or on the Web only. For further information on the preparation of electronic artwork, please see . Please note: Because of technical complications which can arise by converting colour figures to "grey scale" (for the printed version should you not opt for colour in print) please submit in addition usable black and white versions of all the colour illustrations.


When your manuscript is received by the Publisher it is considered to be in its final form. Proofs are not to be regarded as "drafts".

One set of page proofs in PDF format will be sent by e-mail to the corresponding Author, to be checked for typesetting/editing. No changes in, or additions to, the accepted (and subsequently edited) manuscript will be allowed at this stage. Proofreading is solely your responsibility.

A form with queries from the copyeditor may accompany your proofs. Please answer all queries and make any corrections or additions required.

The Publisher reserves the right to proceed with publication if corrections are not communicated. Return corrections within 2 days of receipt of the proofs. Should there be no corrections, please confirm this.

Elsevier will do everything possible to get your article corrected and published as quickly and accurately as possible. In order to do this we need your help. When you receive the (PDF) proof of your article for correction, it is important to ensure that all of your corrections are sent back to us in one communication. Subsequent corrections will not be possible, so please ensure your first sending is complete. Note that this does not mean you have any less time to make your corrections, just that only one set of corrections will be accepted.

Offprints
The corresponding author, at no cost, will be provided with a PDF file of the article via e-mail. The PDF file is a watermarked version of the published article and includes a cover sheet with the journal cover image and a disclaimer outlining the terms and conditions of use.

Virology Protocols
Protocols are to be submitted in the same way as regular articles

Organization of a Protocol

Title page:
The title page should contain the following items: (i) complete title (preferably no chemical formulas or arbitrary abbreviations); (ii) full names of all authors; (iii) complete affiliations of all authors; (iv) the number of text pages of the whole manuscript (including figures and tables) and the number of figures and tables; (v) the name and complete address of the corresponding author (including telephone number, facsimile number and electronic mail address); (vi) acknowledgements.

Abstract:
This should provide a concise description of the purpose of the Protocol and should not exceed 200 words.

Keywords:
Please provide 3 - 6 keywords.

Type of research:
In this section, relevant published studies should be described concisely in list form preceded by Roman lower case numeral characters. The published studies should be appropriately cited.

Time required.
An estimation of the time required to run the protocol should be given per separate step and for the whole protocol.

Materials
The materials used should be described in sufficient detail for the protocol to be replicated. Animals used should include information on breed, breeder, sex, age, weight and the maintenance conditions. Furthermore, this section should be divided into two subsections: (i) Special equipment and (ii) Chemicals and reagents. Any special equipment required should be mentioned, including details of model type/number and (international) supplier. The source or supplier of any special equipment should also be stated, in parentheses, after mentioning the equipment for the first time. A listing (preceded by dashes) of chemicals and reagents used in the protocol, should be provided, if applicable. Special chemicals and drugs with their sources or suppliers should be grouped under a separate subheading ("Chemicals" or "Drugs"). For drugs, generic names should be used; trade names may be given in brackets where the drug is first mentioned. In case of new drugs or chemicals, a full chemical description (formula) should be given. The form of the drug used should be indicated.

Detailed procedure.
This section should include an extensive, detailed and stepwise description of the procedures used. The individual steps should be described in list form preceded by Roman lower case numeral characters and correspond with the steps described under Quick procedure. All companies from which chemicals or materials were obtained should be listed with their full address.

Results.
In this section the expected results should be described clearly and concisely, and in logical order without extended discussion of their significance. Results should usually be presented descriptively and be supplemented by photographs or diagrams.

Discussion.
This section should present an assessment of the protocol, problems which may be encountered, and alternative or support protocols.This section should be divided into two parts: (i) Trouble-shooting and (ii) Alternative and Support Protocols. Troubleshooting: Problems that may have been encountered during any of the procedures should be discussed clearly and concisely, and suitable solutions suggested. Alternative methods for replacing certain steps in the protocol should be mentioned in sufficient detail, and clearly indicating at which point in the protocol they should be applied.Alternative and Support Protocols: If applicable, alternative or support protocols should be mentioned, clearly stating the advantages and disadvantages of such protocols and be accompanied by appropriate citation of the literature.

Essential literature references.
This should mention certain essential reading divided into original papers, book chapters and review papers. Do not cite the full reference, but just list the reference number. All references cited in the text should be listed at the end of the manuscript, arranged in alphabetical order of the author's surname.

Quick procedure.
This section should describe the protocol in a concise, stepwise manner. The individual steps should be described in list form preceded by roman lower case numeral characters and correspond with the steps described under Detailed procedure. This section should contain basic, essential information for the protocol to be replicated successfully.

Illustrations.
Follow the standard article guidelines for instructions on illustrations.