Zika virus spreads through sexual contact and researchers have uncovered how this transmission occurs. The new findings can help develop targeted drugs to fight off Zika virus.
Lead researcher Shee-Mei Lok said, “This is exciting, as our structure will provide important clues to other researchers around the world who are working to find therapeutic agents against the Zika virus.”
For the study, researchers imaged the Zika virus under a cryo-electron microscope. The researchers used thousands images to reconstruct a high-resolution cryo-electron structure of Zika. This reconstructed virus showed that Zika’s overall virus architecture is similar to other flaviviruses, like West Nile or dengue. On the other hand, the researchers also found that Zika is more thermally stable than the dengue virus, and it is more structurally stable even when incubated at 40 degrees, which mimics fever patients.
Surface proteins of Zika virus have tighter interactions, compared to the dengue virus, adding to its stability. This may explain why Zika virus can survive in urine, semen, and saliva. Aside from Zika transmission through a mosquito bite, the virus is particularly resilient thanks to its structural stability, which helps explain how it can be transmitted through sexual intercourse. Other mosquito-borne viruses cannot be transmitted sexually.
The findings imply that possible treatment methods for Zika can work by weakening the structure of the virus, thus helping reduce illness severity and limiting its spread.
“Additionally, we have shown that the Zika virus contains structures that are unique from the viruses in the same family that affect brains, such as the West Nile virus, and also those that cause fever, such as the dengue virus. These structures can be mutated to better understand how they influence the Zika virus infection in humans and can also potentially lead to the development of a safe vaccine that has reduced side effects,” explained Lok.
Professor Lok’s next steps are to test the effectiveness of antibodies on the Zika virus.
The structural differences between Zika virus and dengue could also help explain why Zika virus contributes to birth defects and dengue does not. Researchers have found one large structural difference in Zika, which distinguishes it from other flaviviruses.
In an alternative study carried out by researchers at Purdue University, lead study author Dr Richard Kuhn said, “The structure of the virus provides a map that shows potential regions of the virus that could be targeted by a therapeutic treatment, used to create an effective vaccine or to improve our ability to diagnose and distinguish Zika infection from that of other related viruses.”
“Determining the structure greatly advances our understanding of Zika – a virus about which little is known. It illuminates the most promising areas for further testing and research to combat infection,” he added.
As Zika continues to spread, it is important that additional research continues to advance towards a better understanding of the virus in order to come up with a vaccine or cure.
Zika virus sexual transmission: New safety guidelines
The Centers for Disease Control and Prevention (CDC) has reported that Zika virus can be sexually transmitted from an infected man. In known cases of the sexual transmission, the man has often had the symptoms, which suggests that Zika can be transmitted regardless of the manifestation of the symptoms, as it is known to remain longer in semen compared to blood.
Unfortunately, there is still much unknown about the sexual transmission of Zika virus. It is unclear how long exactly the virus can stay in semen, it is unknown whether the infected men who never manifest the symptoms can transmit the virus and whether a woman can transmit Zika through sex, and it is unclear if Zika virus can be transmitted through oral sex.
When it comes to condom use to prevent the spread of Zika, here are some tips to consider:
Use a condom if the man has been infected or shows symptoms.
Use a condom if the man has travelled to Zika-infected countries or avoid sex for at least eight weeks.
If the man lives in a Zika-infected country but does not show symptoms, still use a condom or abstain from sex for a while.
Zika confirmed to cause birth defects in babies
The Centers for Disease Control and Prevention has now confirmed that Zika virus is linked to cause brain defects in babies. Dr. Tom Frieden from the CDC said in a news statement, “It is now clear. The CDC has concluded that Zika does cause microcephaly. There is still a lot that we don’t know, but there is no longer any doubt that Zika causes microcephaly”. Continue reading…
Autoimmune brain disorder tied to Zika virus
The Zika virus, which is spreading across Brazil and the world, may be linked to an autoimmune brain disorder, according to new findings. The researchers suggest this autoimmune brain disorder is similar to multiple sclerosis. So far, Zika virus is already tied to a birth defect known as microcephaly and Guillain-Barre syndrome. Continue reading…