Dengue has become a health problem
for tropical areas of Latin America over the last
several decades. But this disease, cause by four types
of virus transmitted by a mosquito, has been known
The viruses -- with the scientific
labels DEN-1, DEN-2, DEN-3 and DEN-4 -- can cause
different manifestations of dengue, the most serious
form being hemorrhagic dengue, which can be mortal.
The Pan-American Health Organization
(PAHO) has deployed intense operations to aid countries
in their battles against the epidemic. On the Internet
is a website that serves as the PAHO's
center of operations, providing information about
the traits of the disease and its presence in the
According to the history
of dengue in the Americas included on the PAHO
site, the disease is believed to have first appeared
in 1635 on Martinique and Guadalupe. In the 18th century,
dengue epidemics were recorded in the United States,
Asia and Africa, and later in Peru.
The resurgence of dengue in recent
times, which has hit Venezuela, Colombia and Brazil,
and more recently El Salvador and Honduras, is directly
related to the proliferation of the virus's
vector of transmission, the Aedes aegypti mosquito.
This mosquito species is at home
in the urban environment and its presence is reinforced
by phenomena like the growth of metropolitan areas
and the deterioration of sanitary conditions. The
campaigns against dengue are focused on eradication
of the Aedes aegypti.
According to figures from the
Health Organization (WHO), the scope of dengue
infection has risen dramatically in recent decades
and is now an endemic disease in more than 100 countries,
endangering some 2.5 billion people.
The Internet holds abundant information
about dengue, such as websites with frequently
asked questions, explanations about symptoms and treatment,
and even lists of health experts dedicated to combating
Health Organization (PAHO): Dengue
History of Dengue in the Americas
Health Organization: Dengue
Centers for Disease Control
view of dengue virus
A Cup of Tea
Tea is a plant of Chinese origin
which gave rise to the most widely consumed beverage
in the world, from the far East to Latin America.
It was first consumed by human beings nearly 5,000
Descriptions of the history of
tea found on the Internet cite the legend of Chinese
Emperor Shen Nung, an herbalist who discovered tea
by chance one day as he sat under a wild tea tree,
leaves from the tree fell into a pot of boiling water,
and he decided to try the brew.
China is considered the birthplace
origin of tea or "cha", which was spread
throughout Asia, and later the world, by merchants
According to a website that provides
answers to frequently
asked questions about tea, there are 3,000 varieties
today, although true tea is always brewed from the
leaves of Camellia sinensis, the scientific name for
There are three basic types of
tea, depending on the degree of fermentation of the
leaves: green, black and oolong. Most of the tea consumed
in the West is black.
Many varieties of tea are known
by their place of origin, and tea-lovers are familiar
with their specific flavors, aromas and characteristics.
The widespread consumption of
tea has led to the cultivation of the plants across
the world. More than 35
nations in Asia, Africa, the Americas and Oceania
are listed as tea producers on a website that reports
their share of the competitive global market, which
has given rise to institutions like the tea
council that links a number of the main exporters.
- home page
in the world
world of tea
asked questions about tea
Mangroves populate the coasts
of many tropical and subtropical areas of the world,
serving as the backbone of an ecosystem that sustains
a great wealth of biodiversity. However, their future
is threatened by deforestation and the degradation
of their habitat.
Mangrove forests grow in areas
where there is abundant water, a mix of fresh and
sea water, an ecosystem
of marshes or swamps.
According to one Internet site
explaining the taxonomy
of this unique tree, there are some 100 species within
the mangrove family, all of which are vascular plants.
Resistant to salinity, mangroves
grow in coastal areas, such as estuaries, and their
wood is highly prized. They normally have extensive
roots, some of which extend from the trunk and are
partially exposed to the air and partially submerged
in its watery environs.
These trees produce nutrients
that allow a great variety of air, land and aquatic
life forms to flourish. The loss of the ecosystem
they create means a reduction in biodiversity, coastal
erosion, and poor water quality, according to organizations
that promote mangrove conservation and sustainable
Some of these groups are leading
intensive campaigns to save the mangrove, such as
Action Plan, which reports that there was a time
when three-quarters of the world's tropical and subtropical
coasts were populated by these trees. Today, just
a portion of that area remains, and at least half
is threatened with destruction.
According to the United Nations
Food and Agriculture Organization (FAO),
mangrove forests cover a total of 181,000 square km
in different parts of the world.
Art by Kids
and rainforests: Mangroves
Information on Mangroves