Vector-Borne and Tropical Diseases

We have the tools to help you develop new assays

• Vector-borne diseases account for more than 17% of all infectious diseases, causing more than 700,000 deaths annually.¹

• More than 3.9 billion people in over 128 countries are at risk of contracting dengue, with 96 million cases estimated per year.¹

• Malaria causes more than 400,000 deaths every year globally, most of them children under 5 years of age.¹

• Other diseases such as Chagas disease, leishmaniasis and schistosomiasis affect hundreds of millions of people worldwide.¹

• Alphavirus	• Japanese Encephalitis Virus	• Nipah Virus
• Borrelia burgdorferi (Lyme disease)	• Leishmania	• Tick-borne Encephalitis virus
• Borrelia garinii	• Leptospirosis	• West Nile Virus
• Chagas	• Malaria	• Yellow Fever Virus
• Chikungunya	• Marburg Virus	• Zika Virus
• Dengue	• Mayaro Virus
• Ebola	• Newcastle Disease

Vector-Borne and tropical diseases occur principally in the tropics with the term ‘tropical disease’ relating to those that thrive in hot, humid conditions such as leishmania, Chagas, Ebola, Marburg virus and many more. Vector-Borne diseases are further categorised by the fact that they’re transmitted between Humans by a vector that is typically a blood-sucking arthropod such as a mosquito, tick or flea. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.

Mosquito. A vector for tropical diseases such as Dengue and malaria.

Deer tick (Ixodes scapularis) a vector for Lyme disease.

In practise, these diseases are most prevalent in some of the poorest regions of the world in peoples who live in remote, rural areas, urban slums or conflict zones. The geographical location of these diseases makes it further difficult to treat and control outbreaks of these diseases, manage the underlying infection route and vaccinate, where possible. It is therefore essential that we can develop low-cost, sensitive, means of diagnosis with low-cross reactivity to other infectious diseases so early diagnosis is possible and treatment most effective.

To assist in this endeavour, Biorbyt offer a wide range of antigens and antibodies to assist researchers in the development of tests such as solid-phase, dip-sticks (ELISA), particle agglutination and lateral flow.

Validated, Matched antibody pairs

Disease	Capture	Detection
Dengue Virus NS1	orb55887	orb55886
	orb55887	orb107981
	orb107981	orb107978
	orb107981	orb107979
	orb107981	orb107980
Ebola NP	orb421067	orb421068
Japanese Encephalitis Virus NS1 (JEV NS1)	orb525776	orb52577
	orb525776	orb525778
	orb525776	orb525779
	orb544441	orb52577
	orb544441	orb525778
	orb544441	orb525779
Malaria HRP-2	orb316676	orb316675
Malaria pLDH	orb316685	orb316686
	orb316684	orb316686
Malaria (Specific P. falciparum HRP-2)	orb23592	orb23594
	orb23592	orb23593
	orb316687	orb316688
Nipah Virus G protein	orb421078	orb421077

Disease	Capture	Detection
Yellow Fever NS1	orb55885	orb55880
	orb55885	orb55881
	orb55885	orb55884
	orb55885	orb55883
	orb55885	orb402858
	orb55880	orb55884
	orb55880	orb55881
	orb55880	orb402858
	orb55880	orb55883
	orb402858	orb55884
	orb402858	orb55883
	orb402858	orb55881
	orb55881	orb55884
	orb55881	orb55883
	orb55883	orb55884
Zika Virus NS1	orb371979	orb371980
	orb378455	orb378456
	orb378456	orb378456
	orb378455	orb383474
	orb378456	orb383475
	orb383474	orb378456

Developing your own assay

Tested in ELISA, IFA, LF, often WB or IHC-P, we have antibodies and antigens that you can test together to optimise your own immunoassay to these devastating diseases. Search our website, or ask us at to find the right products for your work:

Antibodies	Antigens
Alphavirus
Borrelia burgdorgeri	Borrelia afzelii, burgdorferi and garinii
Chikungunya Virus and Envelope protein	Chagas (Trypanosoma cruxi)
Dengue Virus and NS1	Chikungunya Virus
Ebola Virus	Dengue Virus Type 1, Type 2, Type 3 & Type 4
Japanese Encephalitis Virus (JEV) and NSA	Ebola Virus
Leptospira biflexa	Leishmania
Malaria, plus Plasmodium falciparum and	Japanese Encephalitis Virus
Plasmodium vivax	Mayaro Virus
Marburg Virus	Nipah Virus
Newcastle Disease Virus	Malaria (Plasmodium falciparum and vivax)
Nipah Virus G protein	Tick-borne Encephalitis Virus
West Nile Virus, Envelope protein	West nile Virus
Yellow Fever Virus NS1	Yellow Fever
Zika virus, NS1 and Envelope protein	Zika Virus

Tips and tricks for working with Flaviviruses in EIA assays

Many Vector borne diseases are caused by viruses from the genus Flavivirus of the family Flaviviridae. This family comprises over 70 viruses including dengue (DEN) viruses, Japanese encephalitis (JE) virus, St. Louis encephalitis (SLE) virus, and yellow fever (YF) virus many of which are important human pathogens. ²

As all Flaviviruses are antigenically related to various degrees, it is essential that when developing an immunoassay, the antibodies used are specific to the disease of interest. High genetic homology between the different Virus species means that development of antibodies with no cross-reactivity to other flavivirus caused diseases is difficult.

Zika virus

EIA assay

Flaviviruses are simple enveloped viruses containing single-stranded RNA associated with a capsid protein. All share symmetry, appearance and their genomes encode a single, large polyprotein that is proteolytically processed to yield structural domains - E (Envelope), prM (precursor of membrane(M)) and Capsid protein. They also contain several non-structural proteins (NS) such as NS1, NS2, NS2b, NS3, NS4a, NS4b and NS5.3

It is important to note that the dominant protein is the Envelope protein (E), which is present on the surface of the viron. It contains highly conserved regions and so antibodies to Envelope proteins are often cross-reactive to other serotypes and diseases. The NS1 protein is a glycosylated, membrane-bound secreted glycoprotein that has replicative and evasive functions. NS1 antigens can be detected early on in infection and are an excellent target for early diagnostic tests. NS1 is serotype-specific and so detection of NS1 antigens can enable virus serotyping by ELISA.

In order to improve the specificity of an assay, it is vital to remove cross-reacting antibodies that can lead to false positives by binding the antigen non-specifically. This can be achieved via defined epitope blocking ELISA’s that permit differentiation of flaviviral infections by targeting epitopes on NS1 or E proteins. If low concentrations of unconjugated antigens from the potentially cross-reactive serotypes are included in the assay, these will block binding of the cross-reactive antibodies to the target antigen, thereby increasing assay specificity.

References

1. Vector-borne diseases. Available at: https://www.who.int/news-room/fact-sheets/detail/vector-borne-diseases. (Accessed: 25th January 2019)

2. Kuno, Goro, Chang, G.-J. J., K. Richard, T., Nick, K. & C. Bruce, C. Phylogeny of the Genus Flavivirus. J. Virol. 72, 73–83 (1998).

3. Heinz, F. X. & Stiasny, K. The Antigenic Structure of Zika Virus and Its Relation to Other Flaviviruses: Implications for Infection and Immunoprophylaxis. Microbiol. Mol. Biol. Rev. 81, e00055-16 (2017).