But what happens when a prawn gets sick? While humans can’t become unwell from these pathogens detected on prawn farms, these diseases can cause losses in prawns or negatively impact their growth cycle.
“Aquaculture has the potential to meet a lot of our food demands and provide food security in the future, but diseases in aquaculture are a very big barrier to the improvement of production, efficiency and sustainability in the industry,” Phoebe says.
“Prawns are extremely challenged by diseases. One reason for this is because they lack the same immune components that vertebrates have,” she says. “Fish, for example, can be vaccinated like a human because they produce antibodies that can be used to fight the infection. Prawns are very different and vaccinating them cannot currently provide any long-term protection against diseases.” Phoebe says that prevention is the best cure when it comes to prawn pathogens, highlighting the importance of biosecurity and ensuring Australia's prawn stocks are healthy and disease-resistant.
“The Australian prawn industry is still relatively reliant on wild-caught prawns to produce seed stock, so we analysed these wild-caught prawns to assess the risk of collecting stock infected with pathogens and how likely this is to introduce pathogens into farm production systems,” she says.
“Our research also investigates the potential for these production prawns to be infected with more than one pathogen (co-infections). Previous research hasn’t always accounted for this, and so it hasn’t been able to show a causal relationship between the presence of a certain pathogen and a disease event in prawns; we know the certain pathogen has been detected, but infection with a pathogen doesn't necessarily lead to disease outbreak. The presence of co-infections can further complicate the interpretations from such studies.
“So, my research is attempting to define these causal relationships, by only challenging (injecting) prawns that are free of other pathogens known to be present in Australian prawns with one purified virus," Phoebe says. "Through this, we can get really robust experimental findings that show the significance of these viruses in production and elucidate the impact of the virus on the health of the prawn without potential confounding effects from co-infections.”