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vaccination

(Encyclopedia)vaccination, means of producing immunity against pathogens, such as viruses and bacteria, by the introduction of an killed or weakened microorganism, a harmless piece of a microorganism, or the like t...

anise

(Encyclopedia)anise ănˈĭs [key], annual plant (Pimpinella anisum) of the family Umbelliferae (parsley family), native to the Mediterranean region but long cultivated elsewhere for its aromatic and medicinal qual...

ehrlichiosis

(Encyclopedia)ehrlichiosis ârlĭkēōˈsĭs [key], any of several diseases caused by rickettsia of the genera Ehrlichia and Anaplasma. Ehrlichiosis is transmitted by ticks. Both human forms tend to develop about n...

communicable diseases

(Encyclopedia)communicable diseases, illnesses caused by microorganisms and transmitted from an infected person or animal to another person or animal. Some diseases are passed on by direct or indirect contact with ...

epidemic

(Encyclopedia)epidemic, outbreak of disease that affects a much greater number of people than is usual for the locality or that spreads to regions where it is ordinarily not present. A disease that tends to be rest...

antiviral drug

(Encyclopedia)antiviral drug, any of several drugs used to treat viral infections. The drugs act by interfering with a virus's ability to enter a host cell and replicate itself with the host cell's DNA. Some drugs ...

meningitis

(Encyclopedia)meningitis sĕrˌəbrōspīˈnəl [key], acute inflammation of the meninges, the membranes that cover and protect the brain and spinal cord. It can be caused by bacteria, viruses, fungi, or other orga...

virus

(Encyclopedia)CE5 Structure of a tobacco mosaic virus, an RNA-containing virus virus, parasite with a noncellular structure composed mainly of nucleic acid within a protein coat. Most viruses are too small (100...

Natives, North American

(Encyclopedia)Natives, North American, peoples who occupied North America before the arrival of the Europeans in the 15th cent. They have long been known as Indians because of the belief prevalent at the time of Co...

Austria

(Encyclopedia)CE5 Austria ôˈstrēə [key], Ger. Österreich [eastern march], officially Republic of Austria, federal republic (2020 est. pop. 8,917,000), 32,374 sq mi (83,849 sq km...

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