Questões Militares

         Chagas disease, also known as American trypanosomiasis, is a potentially life-threatening illness caused by the protozoan parasite Trypanosoma cruzi. About 6-7 million people worldwide are estimated to be infected with T. cruzi. The disease is found mainly in endemic areas of 21 continental Latin American countries, where it has been mostly transmitted to humans and other mammals by contact with feces or urine of triatomine bugs (vector-borne), known as kissing bugs, among many other popular names, depending on the geographical area.

        Chagas disease is named after Carlos Ribeiro Justiniano Chagas, a Brazilian physician and researcher who discovered the disease in 1909. Chagas disease was once entirely confined to continental rural areas of the Region of the Americas (excluding the Caribbean islands). Due to increased population mobility over previous decades, most infected people now live in urban settings and the infection has been increasingly detected in the United States of America, Canada, and many European and some African, Eastern Mediterranean and Western Pacific countries.

           Chagas disease’s transmission is caused by T. cruzi parasites, which are mainly transmitted by contact with feces/urine of infected blood-sucking triatomine bugs. Normally they hide during the day and become active at night when they feed on animal blood, including human blood. They usually bite an exposed area of skin such as the face (hence its common name, kissing bug), and the bug defecates or urinates close to the bite. The parasites enter the body when the person instinctively smears the bug’s feces or urine into the bite, other skin breaks, the eyes, or the mouth. T. cruzi can also be transmitted by consumption of food or beverages contaminated with T. cruzi through, for example, contact with feces or urine of infected triatomine bugs or common opossums. This kind of transmission typically causes outbreaks with more severe cases and mortality; passage from an infected mother to her newborn during pregnancy or childbirth; blood or blood product transfusion from infected donors; some organ transplants using organs from infected donors; and laboratory accidents.

Internet: <who.int>  (adapted). 

           In 2020, the state of California experienced its worst wildfire season on record, with the Bay Area fire becoming one of the largest wildfires in American history. By the end of the year, the state recorded more than 8,600 blazes that burned down over 4 million acres of land, accounting for more than 4% of the state’s total land area.

         California is known for its wildfire seasons, which usually take place between late summer and early autumn, though they have been getting significantly more intense, destructive, and longer in the past two decades. At least one-third of the worst wildfires in USA (United States of America) history occurred in California. But what causes California such susceptibility to wildfires in the first place and what is causing the exacerbation of it?

          Wildfires can occur naturally and as a result of human activity, but three elements must be present for a wildfire to start. Fuel: Any flammable material surrounding a fire, which can come in the form of live or dead trees, dry vegetation, and other organic matter; Air: An abundance of oxygen supply. Heat sources: to ignite and burn the fuel. This could take the form of lightning strikes or human sources such as campfires or cigarettes.

          Natural wildfires, which are classified as natural disasters by the Environmental Protection Agency, can start during low precipitation, dry weather and droughts. During these conditions, dry vegetation becomes the perfect fuel for wildfires and when lightning strikes, it ignites a fire that can spread rapidly with the aid of strong winds and elevated temperatures.

Internet: <earth.org> (adapted).

    No one enjoys a delayed flight, but as our weather gets warmer, we can expect more of them.

   That's according to experts, who say that the heat of the summer might cause more delays.

    Bloomberg looked at US data for flight delays at airports in Chicago and New York from June to August in 2022 and from January to March in 2023. It found that there were more delayed flights in the summer months at both airports.

    When the temperature rises above 39 degrees Celsius, things get very difficult for airlines, Bijan Vasigh, a professor at Embry-Riddle Aeronautical University in the US, told Bloomberg.

    The air is thinner when it gets hot and that makes it harder for planes to take off. In thinner air there is not as much lift, so more power is needed.

     When they need more power, it helps to have a lighter airplane.

    That might mean pilots have to make last-minute decisions to reduce the weight on board by dumping fuel, passengers or baggage — meaning the plane will probably be delayed.

    The problem gets worse at airports that are at a higher altitude where the air is already thinner, and at airports with short runways, since planes need more space to get up to a high speed.

   But thin air is not the only problem. Smoke from wildfires — that have been happening all around the world in the summer of 2023 —can also cause flights to be delayed and canceled.

    Of course, the summer is also a busy time when millions of people fly, and weather is not the only cause of delays — but our hotter climate doesn't seem to be helping.

Internet: Engoo