Shigella, causing dysentery and diarrhea, and Escherichia coli, causing urogenital and intestinal infections, are widespread enteric diseases. Lyme disease. This disease is caused by an arachnid, the deer tick, which carries a bacterium called Borrelia bugdorferi.
When a person or warm-blooded mammal is bitten, the bacterium enters the bloodstream, and Lyme disease may occur. The disease was first described in New England and the mid-Atlantic states, but is now known from all of the Northern Hemisphere. Sleeping Sickness.
This disease is also known as African Trypanosomiasis. The disease is transmitted by the Tsetse Fly, in the genus Glossina. The causative agent of African trypanosomiasis is Trypanosoma brucei two forms. The disease is known to have a high mortality rate, not only among people, but among cattle, which was one of the reasons that parts of Africa could not be settled.
Wholesale destruction of habitat and reservoir hosts has had some positive impact on the distribution of the disease. American Trypanosomiasis. This disease is also known as Chagas' Disease. Trvpanosoma cruzi, a protozoan and causative agent of Chagas' Disease, invades the muscle cells of the digestive tract and heart, and sometimes also the skeletal muscle.
They are commonly found around the waist, knees, and elbows. The bite of fleas is very itchy, and it may also lead to infection. A dangerous insect that has different species in the world. Once disturbed, they would sting the intruder repeatedly. A white pustule caused by fire ant sting will last for weeks.
Their venom also would cause several skin problems which may result in an allergic reaction. An aggressive insect that grows up by sucking the blood of vertebrates. Kissing bugs named after their habit of biting the lip of the human while they sleep. Every year up to 40 deaths are recorded by the sting of Japanese Hornet.
The venom of Japanese Hornet would cause an allergic reaction and dissolve tissues within a short time. The repeated stinging from the group of Hornets could also result in death. The deadliest biting insects native to Africa.
They mainly feed on the blood of vertebrates. About half a million people lost their life by the attack of tsetse flies in Africa. At the primary stage, the venom of tsetse flies would make sleeping sickness on the victim. But it may lead to fatality without proper treatment. Also known as Africanized honey bees. They attack the group and made repetitive stinging on the face and eyes of humans. Their toxin is not so dangerous.
Harmful insect pests include caterpillars, grasshoppers and locusts, which eat the leaves, seeds and fruits of crops. At times, locusts can form massive plagues of several million, which can cause widespread damage to crops and lead to famine events. Other insects, including aphids, thrips and weevils, suck the sap from plants, which can affect plant growth and development and make plants more susceptible to disease.
The harmful effects of pests also include carrying and spreading plant diseases that impact agricultural crops. Options for the control of insect pests include spraying pesticides, using smoke, applying irritating chemicals such as capsicum and encouraging biological control by natural predators.
Climate change can increase the amount of damage caused by insects. One example is the European pine beetle, which was introduced to North America and has caused significant damage to pine trees. Many harmful insects can cause painful bites and stings. This can be simply irritating if a single bite or sting occurs, but stinging insects that live in colonies can cause significant injury and even death.
Two examples include the fire ant and the African honeybee, both of which are extremely aggressive when their nests are disturbed. Diseases from insects can cause serious illness and death in humans and other animals. The most deadly animal on Earth is the mosquito, due to its role in the spread of malaria and other diseases.
But if the cow steps on any, a chemical signal in the venom gland, an alarm pheromone, is released that mobilizes the colony for group attack. Known in the southwestern United States since the s, red fire ants have been on a northern expansion which is projected to reach Maryland someday.
When the USDA tried to kill them in Florida flooding with fire hoses, the ants made a watertight ball with the queen in the middle, and it floated on the water. Patients were dying and nurses and nursing assistants were accused of murdering patients.
Some were even serving time in prison by the time the real cause was identified. And they are relentless.
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