The parasite’s eggs are shed in cat faeces, which can then pass on the infection to any warm-blooded animal including birds, sheep, goats, and marine mammals like the endangered Hector’s and Māui dolphins.
Infection of humans can occur through ingesting the parasite’s eggs directly from the environment, such as through unwashed vegetables, or from tissue cysts in improperly cooked meat from an animal that has previously been infected.
Faulkner’s farm is located next to the Tapawera Wastewater Treatment Pond.
Only 37 of Lloyd Faulkner's 146 ewes have lambs, a loss that is expected to cost him at least $14,000. Photo / Max Frethey / Waimea Weekly
He suspected that toxoplasmosis may have spread from flushed contaminated cat litter, which spread through his property by the ducks that swim on the pond’s surface.
But Faulker said the infection could also have come from feral cats in the countryside that are common in the area.
Tasman is estimated to have at least 28,000 feral cats.
Faulkner said he wanted Tasman District Council to publicise the effects of toxoplasmosis and discourage people from flushing cat litter down the toilet.
He also wanted tougher cat control.
“Get the bloody cats chipped and do something about the number of cats,” he said.
“It’s going to cause a hell of a rumpus, but it’s got to be done.”
Elected members were told during the council’s Environment and Regulatory Committee meeting on October 19 that its cat management bylaw, currently in development, will likely require microchipping but not desexing.
“We want to take the community with us in a safe and agreed away,” said environmental information manager Rob Smith.
“The first step in a long path would be microchipping. Once you get to desexing, the cost goes up and you risk alienating a lot more people.”
Farmer Lloyd Faulkner wonders if the ducks that swim on the wastewater treatment pond next to his farm carried toxoplasmosis onto his property. Photo / Max Frethey / Waimea Weekly
The Tasman council, in conjunction with Nelson City Council, is also working towards including feral cats on its joint pest management plan, though feral cat control would be limited to specific, high-value sites.
SPCA scientific officer Christine Sumner said that reducing the number of cats that defecate near food and water supplies for farmed animals may reduce the risk of toxoplasmosis transmission.
“One cat can shed many toxoplasmosis eggs which are hardy and can remain infectious for well over a year after being shed. Therefore, long-term efforts to manage the risk of transmission are needed.”
While desexing companion cats can help reduce the number of unplanned litters and therefore limit the potential numbers of stray cats, the SPCA advocates for a comprehensive approach to cat management.
Sumner also said that cat litter should not be flushed and instead, be placed in a bag and put in the rubbish for disposal through landfill.
Tasman District Council did not plan to test for toxoplasmosis in the wastewater treatment pond by Faulkner’s property as there was no standard test for the disease in wastewater that could produce a validated result.
- Public Interest Journalism funded through NZ On Air
