The Pneumonic plague outbreak in Madagascar has claimed 165 lives, with over 2000 people infected. That is according to the latest data from the World Health Organization. Nine countries that neighbor Madagascar remain on high alert although the plague outbreak appears to have slowed down. W.H.O continues to offer support to the country's public health sector, in monitoring and curbing it's spread. The plague is caused by the bacterium Yersinia pestis and is primarily spread through the bite of infected fleas, which are frequently carried by rats, causing bubonic plague.