Showing: 1 - 4 of 4 RESULTS
Infographics Virus of the Week

West Nile Virus: Virus of the Week

This week on virus of the week is West Nile Virus, another single stranded RNA virus belonging to the flavivirus family! Learn more about other dengue and tick-bourne encephalitis virus!



  • WNV was first isolated from a febrile patient from the West Nile district of Northern Uganda in 1937, (Smithburn et al., 1940).
  • Following naming conventions of the time it was called WNV.

Hosts: What carries WNV?

  • Natural hosts of WNV are mosquitoes and birds, (Jerzak et al., 2005).
  • Culex mosquitoes are particularly important for WNV transmission into humans!
  • Humans are ‘dead end hosts’ – meaning we don’t transmit back to mosquitoes.

Cell Tropism: Which cells can WNV infect?

Vector: What transmits WNV to humans?

  • Culex mosquitoes transmit to humans.
  • This includes: Culex pipiens, C. restuans, C. salinarius, C. quinquefasciatus, C. nigripalpus, C. erraticus and C. tarsalis.

Pathology: What does it do to us?

  • 80 % of infections are asymptomatic.
  • The majority of symptomatic patients experience a weeklong fever.
  • West Nile neuroinvasive disease (WNND) occurs in less than 1 % of infections.

It describes multiple syndromes:

  • West Nile meningitis (WNM)
  • West Nile encephalitis (WNE)
  • West Nile poliomyelitis (WNP)

Did you know?

Men are more likely to experience WNND!


  • Brown, A. N., Kent, K. A., Bennett, C. J., & Bernard, K. A. (2007). Tissue tropism and neuroinvasion of West Nile virus do not differ for two mouse strains with different survival rates. Virology, 368(2),422–430.
  • Byas, A. D., & Ebel, G. D. (2020). Comparative pathology of West Nile Virus in humans and non-human animals. Pathogens, 9(1).
  • Jerzak, G., Bernard, K. A., Kramer, L. D., & Ebel, G. D. (2005). Genetic variation in West Nile virus from naturally infected mosquitoes and birds suggests quasispecies structure and strong purifying selection. The Journal of General Virology, 86(Pt 8), 2175–2183.
  • Kilpatrick, A. M., LaDeau, S. L., & Marra, P. P. (2007). Ecology of West Nile Virus Transmission and Its Impact on Birds in the Western Hemisphere. The Auk, 124(4), 1121–1136.
  • Petersen, L. R., Brault, A. C., & Nasci, R. S. (2013). West Nile virus: review of the literature. JAMA, 310(3), 308–315.
  • Smithburn, K. C., Hughes, T. P., & Burke, A. (1940). A neurotropic virus isolated from the blood of a native of Uganda. The American Journal of Tropical Medicine, 20, 471–497.
Infographics Virus of the Week

Tick-bourne encephalitis virus: Virus of the Week

Today we are introducing you in brief to Tick-bourne encephalitis virus, another flavivirus spread by ticks!


Tick-bourne encephalitis virus (TBEV) is a positive sense single stranded RNA virus, belonging to the flavivirus family. See other flavivirus Dengue here.


The name self-explanatory, a virus which is carried by ticks and causes encephalitis! The first recorded case dates back to the 18th century Scandinavian church records (Lindquist & Vapalahti, 2008).


  • Ixodes spp. a species of tick, transmits the virus to humans, though the cycle includes birds and deer.
  • Nymphs have reduced host specificity – so are the most important for human transmission!

Cell Tropism

  • The brain.
  • Dendritic cells found in the skin.
  • Neutrophils – a type of immune cell.


  • Ixodes spp. are responsible for transmission of TBEV to humans.
  • Habitats range from western Europe to the eastern coast of Japan (Lindquist & Vapalahti, 2008).

Did you know?

Recent studies indicate that the thread of TBEV in europe will escalate with climate change as climate change forces the viruses host northwards. (Nah et al, 2020).


  • Kuno G, Chang GJ, Tsuchiya KR, Karabatsos N, Cropp CB. Phylogeny of the genus Flavivirus. J Virol. 1998 Jan;72(1) 73-83. doi:10.1128/jvi.72.1.73-83.1998. PMID: 9420202; PMCID: PMC109351.
  • Labuda, M., Austyn, J. M., Zuffova, E., Kozuch, O., Fuchsberger, N., Lysy, J., & Nuttall, P. A. (1996). Importance of localized skin infection in tick-borne encephalitis virus transmission. Virology, 219(2), 357–366.
  • Lindquist, L., & Vapalahti, O. (2008). Tick-borne encephalitis. The Lancet, 371(9627), 1861–1871.
  • Nah, K., Bede-Fazekas, Á., Trájer, A.J. et al. The potential impact of climate change on the transmission risk of tick-borne encephalitis in Hungary. BMC Infect Dis 20, 34 (2020).
Infographics Virus of the Week

Dengue Virus: Virus of the Week

This week’s virus of the week is Dengue virus! This virus belongs to the Flavivirus genus and has a positive sense, single stranded RNA genome.

Etymology, where does the name come from?

There are several possibilities:

  • Swahili phrase Ka-dinga pepo (cramp like seizure caused by an evil spirit), which potentially originated from the Spanish word ‘dengue’ meaning careful.
  • Alternatively, posture described resembled a ‘dandy’ in English hence ‘dandy-fever’, (Halstead, 2008) .

What are the Hosts of Dengue Virus?

  • Natural cycles exist between Aedes mosquitoes and non-human primates like gorillas.
  • Rarely, this virus emerges into humans!

Cell tropism of Dengue virus – which cells do they infect?

  • Cutaenous Langerhans Dendritic cells – which are found in the skin.
  • Various immune cells! Including Monocytes, macrophages, as well as B-cells and T-cells.
  • Cells in the brain
  • Endothelial cells, which can be found in blood vessels for example.


  • Aedes mosquitoes are responsible for Dengue transmission.
  • The most prolific mosquito being Aedes aegypti.


There are actually three phases to the Dengue virus infection

Phase 1:

Also known as the febrile phase, where an infected person will have a fever and flu-like symptoms, and potentially a rash. This can last between 3-7 days, and most patients recover after this period.

Phase 2:

Also known as the critical phase, which occurs mainly in children and younger adults. This phase is associated with a vascular leakage syndrome causing low protein and high cell-debris in the blood with fluid around the lungs.

Phase 3:

The recovery phase which can sometimes be associated with another rash.

A second Dengue virus infection is often more severe than the first infection, this is due to a phenomenon known as antibody-dependent enhancement (ADE).

Did you know?

The first suspected cases of Dengue are found in Chinese Medical Textbooks which date back to 992.


  • Balsitis, S. J., Coloma, J., Castro, G., Alava, A., Flores,D., McKerrow, J. H., Beatty, P. R., & Harris, E. (2009). Tropism of dengue virus in mice and humans defined by viral nonstructural protein  3-specific immunostaining. The American Journal of Tropical Medicine and Hygiene, 80(3), 416–424.
  • Blackley, S., Kou, Z., Chen, H., Quinn, M., Rose, R. C., Schlesinger, J. J., Coppage, M., & Jin, X. (2007). Primary human splenic macrophages, but not T or B cells, are the principal target  cells for dengue virus infection in vitro. Journal of Virology, 81(24), 13325–13334.
  • Halstead, S. B. (2008). Dengue (Vol. 5). Imperial College Press. Holmes, E. C., & Twiddy, S. S. (2003). The origin, emergence and evolutionary genetics of dengue virus. Infection, Genetics and Evolution, 3(1), 19–28.
  • Jessie, K., Fong, M. Y., Devi, S., Lam, S. K., & Wong, K. T. (2004). Localization of dengue virus in naturally infected human tissues, by  immunohistochemistry and in situ hybridization. The Journal of Infectious Diseases, 189(8), 1411–1418.
  • King, A. D., Nisalak, A., Kalayanrooj, S., Myint, K. S., Pattanapanyasat, K., Nimmannitya, S., & Innis, B. L. (1999). B cells are the principal circulating mononuclear cells infected by dengue virus. The Southeast Asian Journal of Tropical Medicine and Public Health, 30(4), 718–728.
  • Martins, S. de T., Silveira, G. F., Alves, L. R., Duarte dos Santos, C. N., & Bordignon, J. (2012). Dendritic cell apoptosis and the pathogenesis of dengue. Viruses, 4(11), 2736–2753.
  • Mota, J., & Rico-Hesse, R. (2011). Dengue virus tropism in humanized mice recapitulates human dengue fever. PloS One, 6(6), e20762.
  • Scott, T. W., & Morrison, A. C. (2010). Vector Dynamics and Transmission of Dengue Virus: Implications for Dengue Surveillance and Prevention Strategies BT  – Dengue Virus (A. L. Rothman (ed.); pp. 115–128). Springer Berlin Heidelberg.
  • Weaver, S. C., Charlier, C., Vasilakis, N., & Lecuit, M. (2018). Zika, Chikungunya, and Other Emerging Vector-Borne Viral Diseases. Annual Review of Medicine, 69, 395–408.

Blog Virology Virus of the Week

Introducing: Virus of the Week

Did you know that there are over 1031 viruses on this earth…? That’s ten nonillion?!

You didn’t?

This is Virus of the Week:

The Science Social has made it their mission to introduce a virus each week to help raise general understanding of virology. We don’t think we will get through all the viruses through this series, just a select few.

Here are some of the things that you will learn about each virus that we chose to present to you each week:

  • Taxonomy
  • Etymology
  • Hosts
  • Cell tropism
  • Transmission
  • Pathology
  • “Did you know…?”
  • And of course, a reference list from peer reviewed articles so you can be assured, we are not making it up!

But wait… I don’t know what any of that means…


Taxonomy is a tool used by scientists to classify all living things. Think of it as a bit like a really big, detailed family tree which shows you how closely related each living thing is. This was developed by a Swedish botanist named Carolus Linnaeus back in the 18th century. In short, all living things are grouped into 7 Kingdoms of life; e.g. Animalia, Plantae, Fungi, Chromista, Protozoa, Archaea and Bacteria. Each Kingdom of life are then split further into Phylum > Class > Phylum > Order > Family > Genus > Species.

The scientific classification of a human is:

Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Hominidae
Genus: Homo
Species: sapiens

I’m sure you are all familiar with Homo sapiens, well this is how we, as humans, fit into the taxonomy hierarchy.

Live Science give a good overview of taxonomy here!

The Taxonomy of Viruses though?!

The International Committee on Taxonomy of Viruses (ICTV) are responsible for developing, refining and maintaining a universal virus taxonomy. You can find more out about them here.


This one literally means, where did the name come from.


We will be discussing what hosts the virus of the week can replicate in. We will be looking at viruses where the humans are the main host, but also others too.

Cell tropism:

This is a fancy scientific way of saying, which cells in the body (or organism) the virus is “attracted” too. For example, this virus infects mainly these cells.


How is the virus transmitted?! Through the air? A vector (for example a mosquito or a tick…?), contaminated food or water?


What does the infection of this particularly look like in the form of disease?

Did you know?:

We thought we would throw in a fun fact… just to attempt at making this interesting.

Remember we have a virology section on our blog which you can find here!

We hope you enjoy virus of the week – we are really excited to share this with you!