Children who are not vaccinated by 2 years of age can be vaccinated at later visits. For others at risk, the hepatitis A vaccine series may be started whenever a person wishes to be protected or is at risk of infection.For travelers, it is best to start the vaccine series at least one month before traveling.(Some protection may still result if the vaccine is given on or closer to the travel date.).epatitis A is a serious liver disease caused by the hepatitis A virus (HAV). HAV is found in the stool of people with hepatitis A. It is usually spread by close personal contact and sometimes by eating food or drinking water containing HAV.
Poaching, overgrazing and clearing of the land for crops are the main threats. About 16 percent of tropical grasslands have been converted for agriculture or urban development. Desertification is also a significant threat.nimals. Tropical grassland animals (which do not all occur in the same area) include giraffes, zebras, buffaloes, kangaroos, mice, moles, gophers, ground squirrels, snakes, worms, termites, beetles, lions, leopards, hyenas, and elephants.
Grasslands are areas where the vegetation is dominated by grasses (Poaceae), however sedge (Cyperaceae) and rush (Juncaceae) families can also be found. Grasslands occur naturally on all continents except Antarctica. Grasslands are found in most ecoregions of the Earth.For example, there are five terrestrial ecoregion classifications (subdivisions) of the temperate grasslands, savannas, and shrublands biome (' ecosystem '), which is one of eight terrestrial ecozones of the Earth's surface.otable tropical and subtropical grasslands include the Llanos grasslands of South America. Mid-latitude grasslands, including the Prairie and Pacific Grasslands of North America, the Pampas of Argentina, Brazil and Uruguay, calcareous downland, and the steppes of Europe.