Ministry Issues Warning After Black Widow Spider Found

23 August 2001

The Ministry of Health has today issued a warning to food retailers and consumers, after a black widow spider was found in grapes from California.

The female spider was found while the grapes were in a storage warehouse in Feilding.

Chief Advisor Safety and Regulation, Dr Bob Boyd said other black widow spiders may have arrived in New Zealand undetected, and retailers and consumers should remain vigilant.

"Although the black widow spider is not normally aggressive, it will bite to defend itself or its eggs. The spider is venomous and its bite contains a toxin. The effect of the bite may result in abdominal pain, breathing difficulties, nausea and vomiting. Full recovery may take up to 10 days."

Dr Boyd said it was highly unlikely that a healthy person would die as a result of a black widow spider bite, however very young, very elderly or debilitated people were at greater risk.

The symptoms of a bite may include sharp pain at the site, followed by development of cramping pain through the body over a period of about one hour. Abdominal pain maybe severe, and other symptoms include nausea, vomiting, headaches, sweating and salivation with restlessness.

The male spider has an elongated black shiny body, with white and red markings on its side. The female's abdomen is almost spherical, usually with a red hourglass mark on its back or two red marks on its back. It may grow up to the size of about a 20 cent coin.

Dr Boyd said there is a native New Zealand spider that has a similar appearance, but the distinctive feature about the black widow was the markings on its back.

If anyone finds what may be a black widow spider, they should approach with caution. People should avoid physical contact. Fly spray could be used to stun the spider to allow it to be killed and/or placed into a sealed jar.

Dr Boyd said anyone who suspects they may have been bitten by a black widow spider should place ice on the bite, and seek urgent medical attention. The injury is treated symptomatically. If the spider can be captured without endangering anybody, it should be caught to confirm its identification and the local public health service advised.

To date, the Ministry of Health is not aware of any incidents where people have been bitten by black widow spiders in New Zealand.

As far as the Ministry of Health is aware, this is only the third occasion in the past decade that an episode of this nature has occurred. MAF has advised that the risk of black widow spiders becoming established in New Zealand is considered extremely low.

MAF has also advised the Ministry of Health it has suspended any importation of product from a Californian warehouse pending further investigation.

For further information about health aspects contact: Selina Gentry, Media Adviser, ph: 04-496-2483 or 025-277-5411 Internet address: http://www.moh.govt.nz/media.html

For further information about MAF issues contact:

Gita Parsot, Communications Adviser

Contact MPI

for general enquiries phone

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