Web marketing innovator Hugh MacLeod’s latest voucher virus has again become contagious amongst British wine lovers.

Last December, a voucher giving 40% off all Thresher wines for 10 days appeared on the web, driving £15m sales for the off-licence after being reproduced by bloggers and website owners and passed around in emails 800,000 times.

Although the voucher was supposedly intended only for the off-licence’s suppliers and for family of staff, it was actually a promotion cooked up with South African vineyard Stormhoek.

Now Stormhoek marketing director MacLeod has released Thresher Virus 2.0 – and the latest voucher, which runs to April1, is again being shared around offices and other workplaces.

Like the original campaign, Stormhoek and Thresher are investing in no direct marketing and are relying on word-of-mouth, though the retailer has listed the voucher on its website.

Stormhoek uses the blogosphere as a key component in its marketing, having previously delivered free bottles of wine to bloggers who agree to write a review. The promotion delivered a five-fold increase in sales, the company said.

“It’ll be kinda interesting to see if this works out,” MacLeod wrote. “On one level, lightning never strikes twice. On another level, hey, it’s 40% off.”