CONTROL AND PROTECTION TOOLS FOR INTEGRATED PEST MANAGEMENT OF MOSQUITOES AND FILTH FLIES
Location: Mosquito and Fly Research Unit
Title: Between 500,000 and 600,000 cases [of dengue in Texas]
Submitted to: Wing Beats of the American Mosquito Control Association
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 10, 2008
Publication Date: February 25, 2008
Citation: Clark, G. 2008. Between 500,000 and 600,000 cases [of dengue in Texas]. Wing Beats of the Florida Mosquito Control Association. 18(4):16-19.
Interpretive Summary: Dengue fever and its occurrence in southern Texas and northeastern Mexico are discussed by a USDA, ARS scientist with the Center for Medical and Agricultural Research Service in Gainesville, FL. An historical perspective is presented with known occurrences from 1922 to present and its apparent disappearance between 1950 and 1980. From 1980 to present surveillance in Brownsville, Texas has identified the re-appearance of dengue and dengue hemorrhagic fever. Other factors considered include quality of life issues and the lack of air conditioning that places a number of people at risk especially in northeastern Mexico. The greatest density of cases appears in the Rio Grande Valley.
This article summarizes the occurrence of dengue (a mosquito-borne viral disease of humans) transmission in the continental United States beginning with a report of 500,000 cases in 1922 in Texas. While about 1,400 cases were reported in 1923 and 1924, an average of only 80 or fewer cases was reported annually during the following 25 years. From 1950 through 1980, the number of reported cases dropped even further, when it appeared that dengue transmission had completely stopped in Texas. Since then, with the increasing frequency of dengue epidemics in northern Mexico, dengue transmission increased in the Rio Grande Valley and significant outbreaks occurred in 1995, 1999, and 2005. Serosurveys conducted immediately following the last two outbreaks (in Nuevo Laredo and Brownsville) reflected that 38 percent and 40 percent, respectively, of residents studied were infected with dengue during these outbreaks. This was a much greater number of infections than the number of cases detected by existing surveillance programs. This suggests that many inapparent infections are occurring in this area of the U.S. and may place residents of south Texas at risk of dengue hemorrhagic fever in the future.