Disease Vectors and Pathogens

Duration of exoerythrocytic cyle is 8 days in Plasmodium vivax, while it is 14-15 days in Plasmodium malariae. Incubation period is 12-14 days Plasmodium vivax, while it is 20-24 days in Plasmodium malariae.

Parasites like Trichinella frequently increase the IgE levels, usually polyclonally. This tends to inhibit the protective effect of IgE by diluting out the specific IgE on the mast cell. Inflammation induced by mast cell degranulation leads to influx of IgG, which causes damage to the parasite.

Listeria monocytogenes is able to escape from phagocytic vacuoles and survive in the cytoplasm of phagocytic cells.

Aedes aegypti is the primary mosquito vector responsible for transmitting dengue fever. Unlike Anopheles mosquitoes that transmit malaria, Aedes aegypti is a day-biting mosquito found in tropical and subtropical regions. Plasmodium refers to the malaria parasite, while male Anopheles mosquitoes do not bite humans.

All of the above viral diseases are transmitted by mosquitoes.

Rabies remains as one of the most feared zoonotic diseases in the world. In humans it is a lethal encephalitis. Carnivores, such as the dog, wolf, fox, and skunk, are the principal reservoirs, but the infection extends to bats and to some domesticated animals, such as cattle, goats, and swine. The infectious agent is transmitted to humans through contaminated saliva introduced into the wound of a bite.

The Liliaceae contains 13 genera and about 400 herb species. Many of these plants adorn our gardens and walkways. Tulips are in the genus Tulipa. This family has been split several times. Liliaceae used to be a large family including many Lily-like species. It used to contain many families that were lily-like. They included garlic, onions, asparagus, amaryllis, and agavaes. Today, the family is relatively small.

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Leishmaniasis is caused by Leishmania donovani and is transmitted by sand flies. Leishmaniasis has a wide distribution that extends from the Mediterranean to Middle Asia, to southern Russia and China. It is also known as Kala-azar (black fever) or Assam fever.

Balantidaisis is a form of dysentry. It is caused by the only ciliated protozoan parasite of humans (Balantidium coli). This parasite is found worldwide. There is a slight correlation between the incidence of the disease and the presence of hogs. The balantidaisis organisms feed on epithelium and red blood cells in the colon and can cause ulcers.

Trich is a sexually transmitted disease, and is caused by the single-celled protozoan parasite, Trichomonas vaginalis, producing mechanical stress on host cells and then ingesting cell fragments after cell death. It is primarily an infection of the urogenital tract. The most common site of infection is the urethra and the vagina in women.

Trichomonas vaginalis, a protozoa, causes (the usually sexually transmitted) trichomoniasis. Although asymptomatic most of the times, it needs attention as it is known to facilitate HIV transmission. Symptoms include vaginitis leading to white discharge in women and urethritis leading to burning micturition in men.

Babesiosis is caused by the Babesia parasite, which is carried by ticks. This disease can also be spread through blood transfusions if a donor has a Babesia infection that has not been diagnosed.

Haemogregarina is a genus of hemoprotozoans, parasitic mainly in cold-blooded vertebrates. They are unicellular organisms which are parasitic in the red blood cells.

Cyclosporiasis is an infection with the protozoan Cyclospora cayetanensis, a pathogen transmitted by feces or feces-contaminated fresh produce and water. It is not spread from person to person. It can be a cause of diarrhea for travelers.