Cases of dengue fever have surged in Hawaii and around the world in recent weeks. There is no specific medicine to treat illness caused by the four types of the mosquito-borne dengue virus and, until approval of one live virus vaccine in Mexico this month, no vaccine has been available to the millions of people at risk of infection each year.
A possible new key to preventing the deadly disease within the genes and proteins of infected mosquitoes has been discovered by a team of 12 experts from around the world – including a Central Michigan University researcher – through research funded by the National Institutes for Public Health.
Transmitted by a bite from infected Aedes mosquitoes, the dengue virus can cause dengue fever, hemorrhagic fever and septic shock symptoms. Not only is access to the current vaccine limited, it also varies in its effectiveness to prevent all types of the dengue virus, particularly among children nine years old or younger.
"We will likely be in a position where we are dealing with regular occurrences, as we now are with the West Nile Virus," CMU College of Medicine Assistant Professor Michael Conway said. "We need to think about the future and how we plan to control the disease, even in large cities."
Conway and his colleagues found a key protein in mosquito saliva. When administered to a human in a vaccine, it may block transmission of all four types of the dengue virus by transmitting antibodies to the mosquitoes that bite vaccinated humans.
Dengue virus is not new to the United States. Dengue-related illness has been documented in Florida and Texas, where the virus is now endemic, in recent years. Possible cases also have been found as far back as the 1800s in cities like Philadelphia. Experts believe the risk of dengue-related illnesses will only grow in the coming years due to re-emergence of the virus, the lack of vaccines or medical treatments, and the ease of modern travel. Visitors to a region where dengue is endemic may not always show symptoms, but could carry the virus home and infect a local population of mosquitoes.
This latest research is a significant step forward in preventing dengue virus, but more research must be done to develop a viable vaccine.
"We will hear more about dengue virus until we have an effective vaccine and treatment for all ages and all types of the virus," Conway said. "The scientific community is doing a good job of coming together on research, but we must continue to move forward."