<Tr> <Td_colspan="6"> Note: Other causes of death include maternal and perinatal conditions (5.2%), nutritional deficiencies (0.9%), noncommunicable conditions (58.8%), and injuries (9.1%). </Td> </Tr> <P> The top three single agent / disease killers are HIV / AIDS, TB and malaria . While the number of deaths due to nearly every disease have decreased, deaths due to HIV / AIDS have increased fourfold . Childhood diseases include pertussis, poliomyelitis, diphtheria, measles and tetanus . Children also make up a large percentage of lower respiratory and diarrheal deaths . In 2012, approximately 3.1 million people have died due to lower respiratory infections, making it the number 4 leading cause of death in the world . </P> <P> A pandemic (or global epidemic) is a disease that affects people over an extensive geographical area . </P> <Ul> <Li> Plague of Justinian, from 541 to 542, killed between 50% and 60% of Europe's population . </Li> <Li> The Black Death of 1347 to 1352 killed 25 million in Europe over 5 years . The plague reduced the old world population from an estimated 450 million to between 350 and 375 million in the 14th century . </Li> <Li> The introduction of smallpox, measles, and typhus to the areas of Central and South America by European explorers during the 15th and 16th centuries caused pandemics among the native inhabitants . Between 1518 and 1568 disease pandemics are said to have caused the population of Mexico to fall from 20 million to 3 million . </Li> <Li> The first European influenza epidemic occurred between 1556 and 1560, with an estimated mortality rate of 20% . </Li> <Li> Smallpox killed an estimated 60 million Europeans during the 18th century (approximately 400,000 per year). Up to 30% of those infected, including 80% of the children under 5 years of age, died from the disease, and one - third of the survivors went blind . </Li> <Li> In the 19th century, tuberculosis killed an estimated one - quarter of the adult population of Europe; by 1918 one in six deaths in France were still caused by TB . </Li> <Li> The Influenza Pandemic of 1918 (or the Spanish Flu) killed 25--50 million people (about 2% of world population of 1.7 billion). Today Influenza kills about 250,000 to 500,000 worldwide each year . </Li> </Ul>

Name six parts of the chain of infection