The past can teach us important lessons if we are observant. This is especially true for infectious diseases and the power of immunizations. Vaccines have turned diseases of epidemic proportion into distant memories; it is critical to remember these past events and to use their lessons to guide us as we face new health challenges today.

I invite you to travel back in time. It is the winter of 1964, and Philadelphia and New York are the epicenters of a worldwide viral epidemic that has swept into America from Europe. Transmitted like the common cold, the viral infection is typically not severe. Those afflicted experience a sore throat, watery eyes, and a faint rash, followed by complete recovery. However, if the infection occurs early in pregnancy, the consequences for the developing baby are potentially catastrophic. One percent of infants born to mothers who acquire the infection during the first few months of pregnancy are born with severe birth defects; most of the affected babies experience deafness, heart defects, and cataracts, but virtually every organ of the developing infant can be affected. Twenty thousand babies are born with these abnormalities, and eleven thousand die.  This is the story of the Rubella Virus.

Fast forward to present day, Miami. A viral epidemic is sweeping into the United States from South America. While this virus is transmitted by a mosquito, it also produces mild symptoms: a sore throat, sore joints, and a faint rash.  Many people are not even aware they have been infected. And yet, like the Rubella Virus, an infection that occurs early in pregnancy can be devastating. One percent of infants born to mothers who acquire the infection early in their pregnancy will give birth to babies with severe birth defects, most commonly microcephaly.

The epidemic is happening now and the future is unclear. This is the unfolding story of the Zika Virus.

The epidemic that swept America in 1964 is uncanny in its similarity to what is happening today. Will twenty thousand newborns be born with severe birth defects, as in 1964?

Let’s travel back in time again. Returning to Philadelphia, it is 1969 and a vaccine has been developed. Due to vaccination efforts, by 2004 the Rubella Virus that spread into America from Europe has been completely eradicated from The United States. And just last year, in 2015, the virus was declared eradicated from the Americas.  This is the happy ending to the story of Rubella, and a testimony to the power of vaccines.

As of today, 2016, there is no vaccine for the Zika Virus that is spreading into the northern hemisphere from the south. We need a vaccine, as it will be the ultimate cure. And yet, in the present day United States there are individuals who are skeptical about the benefits of vaccines.

The past is a powerful teacher. As Zika knocks at our door, one only needs to pause and remember the story of Rubella. The benefits of vaccines become crystal clear.