Genetics

Omicron genetics and early transmission patterns characterized

The omicron variant of SARS-CoV-2 diverged from previous SARS-CoV-2 variants as a result of adaptive evolution, in which beneficial mutations are passed on to future generations through natural selection, rather than through ...

Diseases, Conditions, Syndromes

Booster shots needed against omicron, CDC studies show

Three studies released Friday offered more evidence that COVID-19 vaccines are standing up to the omicron variant, at least among people who received booster shots.

HIV & AIDS

Men who paid for sex more likely than other men to live with HIV

Twenty years' worth of surveys suggest that nearly one in ten sexually active men in 35 countries in sub-Saharan Africa have been clients of sex workers, and these men are about 50 percent more likely to be living with human ...

Diseases, Conditions, Syndromes

Is omicron infection inevitable?

Omicron, the latest SARS-CoV-2 variant, is spreading like wildfire across the country. Some experts say it is so transmissible that many people, including those who are vaccinated and boosted, are likely to get it. That is ...

Diseases, Conditions, Syndromes

World can end COVID emergency this year: WHO chief

The head of the World Health Organization said on Monday that the planet can end the COVID-19 emergency this year, although the virus last week killed someone every 12 seconds.

Medications

More than 2 dozen drugmakers to make Merck's COVID-19 pill

A U.N.-backed organization announced Thursday that it has signed agreements with more than two dozen generic drug makers to produce versions of Merck's COVID-19 pill to supply 105 developing countries.

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Africa

Africa is the world's second-largest and second most-populous continent, after Asia. At about 30.2 million km² (11.7 million sq mi) including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area. With a billion people (as of 2009, see table) in 61 territories, it accounts for about 14.8% of the World's human population. The continent is surrounded by the Mediterranean Sea to the north, the Suez Canal and the Red Sea to the northeast, the Indian Ocean to the southeast, and the Atlantic Ocean to the west. Not counting the disputed territory of Western Sahara, there are 53 countries, including Madagascar and various island groups, associated with the continent.

Africa, particularly central eastern Africa, is widely regarded within the scientific community to be the origin of humans and the Hominidae tree (great apes), as evidenced by the discovery of the earliest hominids and their ancestors, as well as later ones that have been dated to around seven million years ago – including Sahelanthropus tchadensis, Australopithecus africanus, A. afarensis, Homo erectus, H. habilis and H. ergaster – with the earliest Homo sapiens (human) found in Ethiopia being dated to ca. 200,000 years ago.

Africa straddles the equator and encompasses numerous climate areas; it is the only continent to stretch from the northern temperate to southern temperate zones.

This text uses material from Wikipedia, licensed under CC BY-SA