New Zealand Outbreak has MPI Scrambling for Answers

A recent outbreak of Yersinia Pseudotuberculosis in New Zealand has the Ministry for Primary Studies stumped
October 18, 2014

A recent outbreak of Yersinia Pseudotuberculosis in New Zealand has the Ministry for Primary Industries (MPI) stumped. 
The Canterbury District Health Board publicly directed the blame towards bagged carrots and lettuces, but others disagree. 

The rare illness has now reached 124 confirmed cases and 6 suspected cases – affecting mainly those ranging in age from 20 to 50 years – but officials are still unsure of the original cause of the outbreak. The Ministry senior communications adviser stated that the source could be anywhere on a broad spectrum from fruits and vegetables to contaminated water and animal contact. Because of its uncommon nature, there is just no way of pinpointing the exact source of the bacteria at this point.

Luckily, while the source remains unclear, officials believe the sudden outbreak is related to a single batch of infected food, and that once it has been processed, the illness will phase out. In the meantime, health officials are urging citizens to take extra care in maintaining personal hygiene, especially during food preparation.

Recognising Yersinia Pseudotuberculosis

Yersinia Pseudotuberculosis is an uncommon bacteria usually hosted in animals and birds, but sometimes it incidentally finds its way into a human host through consumption of contaminated food or water. Although Yersinia originates as a foodborne illness, after contraction, it can also be spread human-to-human. This places extra importance on maintaining clean hands and adhering to food safety practices.

Contrary to the pattern in New Zealand, Yersinia is found most commonly in younger patients (19 and below) and those with weakened immune systems, who are at greater risk of contracting a severe case of the disease.

The symptoms of Yersinia Pseudotuberculosis include fever and pain on the right side of the abdomen, making it easy to confuse with appendicitis. These symptoms differ slightly in young children, and families with young children should be on the lookout for fever, any abdominal pain, and bloody diarrhoea. Severe cases can result in skin rashes, joint pain, and blood infection.

Symptoms usually present themselves four to seven days after contact and will last for one to three weeks. In severe cases, symptoms may persist for three weeks or more.

Preventing the Spread of Bacteria

In order to prevent the spread of Yersinia Pseudotuberculosis, it is necessary for families to take extra food safety precautions during meal preparation. Because the exact source of the bacteria is unknown, extra care should be taken in preparing both meats (particularly pork products) and fruits and vegetables. Ensure that meat is cooked through entirely, reaching an inner temperature of 60°C or above, and that fruits and vegetables are cleansed thoroughly before consumption. Using a mixture of vinegar and water to rinse vegetables has been shown to help stop the spread of bacteria.

Food-serving establishments should also take this opportunity to tighten food safety practices and ensure that the highest food safety standards are being met.