It was also construed, according to an article in the BMJ by Donald Whitfield,  that the same stowaway mosquito also transmitted malaria to a woman who rode through the same village on her motor scooter. High minimum temperatures and humidity were thought to have allowed the infected anopheline mosquitoes to enter the country via aircraft and facilitate their survival. Reports of transmission taking place on the aircraft occurred in the UK in 1984 and 1990, the only such reports on aircraft, leading to infection on aircraft being described as a "British speciality". In 2002, one report came from the vicinity of Heathrow airport.In France, most flights at risk arrive at Charles de Gaulle Airport, Paris, and to a much lesser extent at Marseille, Nice, Lyon, Bordeaux and Toulouse. In 1994, airport malaria was identified in and around Charles de Gaulle Airport in six people, of which four were airport workers, and the others lived 7.5 km (4.7 mi) away in Villeparisis. It was thought that the mosquitoes traveled in the cars of airport workers who lived next door to the two people. All were caused by P. falciparum.In 1989, two cases of falciparum malaria were identified in Italy in two people who lived in Geneva. Distance from the nearest airport ruled out airport malaria in one woman who developed malaria in Italy. A local mosquito (Anopheles labranchiae) had bitten a girl with malaria from India and passed it on.
Usually drainage occurs via the periodontal pocket, or else the infection may spread as a cellulitis or a purulent odontogenic infection. Local anatomic factors determine the direction of spread (see fascial spaces of the head and neck). There may be systemic upset, with an onset of pain and fever. Causes
A periodontal abscess most commonly occurs as a complication of advanced periodontal disease (which is normally painless). A periodontal pocket contains dental plaque, bacteria and subgingival calculus. Periodontal pathogens continually find their way into the soft tissues, but normally they are held in check by the immune system. A periodontal abscess represents a change in this balance, related to decreased local or systemic resistance of the host. An inflammatory response occurs when bacteria invade and multiply within the soft tissue of the gingival crevice/periodontal pocket. A pus-filled abscess forms when the immune system responds and attempts to isolate the infection from spreading. Communication with the oral environment is maintained via the opening of the periodontal pocket. However, if the opening of a periodontal pocket becomes obstructed, as may occur if the pocket has become very deep (e.g. with furcation involvement), then plaque and calculus are trapped inside. Food packing may also obstruct a periodontal pocket. Food packing is usually caused by failure to accurately reproduce the contact points when dental restorations are placed on the interproximal surfaces of teeth. Another potential cause occurs when a periodontal pocket is scaled incompletely.