Growing evidence does suggest that infections are behind many chronic diseases once thought to be caused by genetic, environmental, or lifestyle factors, including peptic ulcers and cervical, liver, and gastric cancers.

Today there are more antiviral drugs available for HIV than for any other viral disease, transforming an infection that was once considered a death sentence into a manageable chronic condition.

Today there are more antiviral drugs available for HIV than for any other viral disease, transforming an infection that was once considered a death sentence into a manageable chronic condition.

Today there are more antiviral drugs available for HIV than for any other viral disease, transforming an infection that was once considered a death sentence into a manageable chronic condition.

Because strep throat is caused by a bacterium called Streptococcus pyogenes, it is treatable with antibiotics but not antivirals. Currently there is no vaccine available to prevent strep throat.

Because strep throat is caused by a bacterium called Streptococcus pyogenes, it is treatable with antibiotics but not antivirals. Currently there is no vaccine available to prevent strep throat.

Because strep throat is caused by a bacterium called Streptococcus pyogenes, it is treatable with antibiotics but not antivirals. Currently there is no vaccine available to prevent strep throat.

Strep throat is a bacterial infection. Hookworm is caused by a parasite and chickenpox and influenza are both caused by viruses.

Strep throat is a bacterial infection. Hookworm is caused by a parasite and chickenpox and influenza are both caused by viruses.

Strep throat is a bacterial infection. Hookworm is caused by a parasite and chickenpox and influenza are both caused by viruses.

The expanded use of cell phones does not have an impact on the spread of infectious disease. Climate change, ecosystem disturbances, war, poverty, migration, and global trade all contribute to the spread of infectious disease.

The expanded use of cell phones does not have an impact on the spread of infectious disease. Climate change, ecosystem disturbances, war, poverty, migration, and global trade all contribute to the spread of infectious disease.

The expanded use of cell phones does not have an impact on the spread of infectious disease. Climate change, ecosystem disturbances, war, poverty, migration, and global trade all contribute to the spread of infectious disease.

Scientists believe that hot weather may speed up both the breeding cycle of mosquitoes and replication of the virus in insects’ guts.

The clearing and settlement of tropical rainforests has exposed woodcutters, farmers, and ecotourists to new vector-borne diseases.

The 1918 influenza pandemic is estimated to have killed between 50 million and 100 million people worldwide. Many of those deaths were due to the effects of pneumococcal pneumonia, a secondary complication of flu for which no antibiotics existed in 1918.

The 1918 influenza pandemic is estimated to have killed between 50 million and 100 million people worldwide. Many of those deaths were due to the effects of pneumococcal pneumonia, a secondary complication of flu for which no antibiotics existed in 1918.

Someone in the world is newly infected with tuberculosis (TB) every second. In 2008 there were an estimated 9.4 million new cases of tuberculosis and 1.8 million deaths.The vast majority of TB deaths are in the developing world, and more than half of all deaths occur in Asia.

Someone in the world is newly infected with tuberculosis (TB) every second. In 2008 there were an estimated 9.4 million new cases of tuberculosis and 1.8 million deaths.The vast majority of TB deaths are in the developing world, and more than half of all deaths occur in Asia.