Infectious: The Return of Days Gone By?
While medical science has made tremendous strides in recent years, some diseases and viruses are re-emerging and creating new challenges for public health professionals.
Published January 1, 2001
By Allison L. C. de Cerreño
Academy Contributor

With winter’s arrival in New York, much of the concern over the West Nile Virus has disappeared – at least among the general population. However, new infectious diseases have emerged in recent years, and there is concern that we may be entering a period in which such diseases, thought to be a bane of the past, may come back to haunt us again.
Annually, infectious diseases kill 13 million people, and together are the leading cause of global fatalities. During the past 20 years, 30 new infectious diseases have been identified. Among these are Hantavirus pulmonary syndrome which was identified in the United States in 1993, with an associated fatality rate of 50%; and Nipah virus which, in 1999, led to fatalities as a result of severe encephalitis in 40% of those infected in Malaysia.
If one were to extend the timeline back two more decades the deadly Marburg virus could be added to the list, having made its first appearance in Germany in 1967. Ten years later, the Ebola virus, an even more virulent cousin, appeared in what is now the Democratic Republic of the Congo. Also in 1977, Legionnaires’ disease was identified in the United States.
Is this New?
So, is this really something new? Some of the emerging diseases of recent years are not really “new,” but better described, more prevalent, or occurring in previously unaffected locales. AIDS, for instance, was practically unheard of worldwide until the early 1980s, but it existed in Africa for many years prior. Similarly, West Nile virus was isolated in Uganda in 1937 but made its appearance in the United States only last year. Others, like Escherichia coli O157:H7, which made its deadly debut in 1982, or the virulent strain of cholera (vibrio cholerae) that struck India in 1992 are new forms of previously well-known disease agents.
However, something is happening that is leading to emerging diseases and to reemerging diseases, either in different forms or in new locations, and human behavior patterns are an important factor. An increase in global travel, for example, has created new and more rapid pathways of exposure. In the case of Lyme disease (1982), economic development has led to loss of natural habitat, placing humans near an ever-increasing population of deer and the ticks that carry the disease. And, increased use and misuse of antibiotics has led to drug resistant strains of tuberculosis, gonorrhea, and meningitis, to name a few.
What can be done? Public health efforts can be stepped up around the world and more attention paid to these human factors. Certainly, more research is needed to understand these diseases and search for vaccines and cures. However, we should keep in mind that only in very recent history and only in some countries have infectious diseases been less prevalent over the past half century. We should be thankful for this respite even as we brace for a possible return of days gone by.
Also read: Unraveling the Mystery in the DRC’s Disease Outbreak—Is It Disease X?