Zika virus has been on our radar since 1947 when it was first isolated from a type of monkey called a rhesus macaque. Less than ten years later, in 1954, the virus was isolated from a human in Nigeria. Most of us are familiar with Zika due to the 2015/2016 outbreak in Brazil during the Summer Olympics. While there have been several research studies focused on how Zika virus infection impacts health (check out the previous PLoSibilities post entitled “Zika virus: the children of the outbreak” for more information), there have not been as many studies focused on how the virus spreads. As such, we still don’t understand how the virus spreads and is maintained outside an urban environment.
Viruses and many other microorganisms that jump between hosts and infect humans have two modes of spread (see figure). The first is called the sylvatic (jungle) cycle. This cycle exists between a wild carrier, like a mosquito, and a non-human primate host, like a monkey. Humans can be infected in a sylvatic cycle, but the primary mode of transmission is between the carrier (mosquito) and host (monkey). The second, and newer, cycle is called the urban cycle, whereby the virus moves strictly between a carrier, like a mosquito, and humans. Malmlov et al. studied the potential role of bats in the sylvatic cycle of Zika viruses. To do so, the researchers inoculated the Jamaican fruit bat (the most abundant bats of the Caribbean, Central America and Mexico) with Zika virus. Following inoculation, they monitored viral replication and effects on bat immune and inflammatory responses. They detected virus in several organs, but it was not found in high quantities in the blood or urine. Moreover, no bats showed any symptoms of disease.
This study helped us understand how Zika virus infects the Jamaican fruit bat, which will aid future ecological studies to track how the virus moves between hosts in sylvatic and urban cycles of transmission.
Summary written by: Emma Finlayson-Trick
To read the full article, please click the following link:
