The Dengue virus is a mosquito-borne virus that has become a significant public health threat in recent years. Originally confined to Southeast Asia, the Dengue virus has now spread to Southern China, Africa, Indonesia, Australasia, Latin America and the United States.
Each year around 50 million people contract the virus, which causes fever, headache, muscle and joint pains, and a characteristic skin rash. There is no current treatment for the virus, preventively or reactively; around one in every thousand cases is fatal. What’s more, the main reasons for the spread of the virus include: urbanisation, global warming and a lack of mosquito control; all of which are still current issues and will continue to contribute to the geographical spread of the virus.
The prominent theory has been that flaviviruses (the group in which Dengue belongs) enter human cells by endocytosis or by fusing with the cell membrane.
In this study, researchers used electron microscopes to watch the early stages of the infection process, labelling the viruses while they entered cells. The results, published in Virology, showed that rather than using a molecular ‘key’ to enter the cell, these viruses may infect cells by directly penetrating its membrane.
Understanding this process could provide researchers with an opportunity to develop treatments and vaccines, helping to protect the 2.5 billion people that are risk of catching the disease globally.
The article is “Flavivirus infection from mosquitoes in vitro reveals cell entry at the plasma membrane” by Ricardo Vacini, Laura D. Kramer, Mariana Ribeiro, Raquel Hernandez and Dennis Brown (DOI 10.1016/j.virol.2012.10.013) and appears in Virology published by Elsevier.