# Presentation: 915782

## World Distribution of Dengue - 2005

**Notes:**
SLIDE 35:  IV-2 - WORLD DISTRIBUTION OF DENGUE, 2005 (map)
Dengue occurs in tropical and subtropical areas in the world. The light blue areas are those at risk for epidemic dengue--that is, those areas infested with Aedes aegypti or other mosquito vectors of dengue. The red areas are those countries with recent dengue activity.

## Dengue in the Americas

- 1980 – 2007 *

- * Data: PAHO (Nov. 30, 2007)

**Notes:**
SLIDE 36:  IV-3 - REPORTED CASES OF DENGUE IN THE AMERICAS, 1980-2007
Dengue epidemics occurred sporadically in the Americas from the 18th to the mid-20th century. Dengue has become an endemic disease since the 1970s. The large bar shown in 1981 is due to a massive dengue hemorrhagic fever epidemic that occurred in Cuba that year. There has been fluctuation in disease incidence from year to year, but 1995 was the worst year since 1981, probably because of the introduction of DEN-3 into Central America in 1994. There is a continuing trend for increasing incidence of disease. 

## Dengue Hemorrhagic Fever in the Americas1980 – 2007 *

- * Data: PAHO (Nov. 30, 2007)

**Notes:**
SLIDE 38:  IV-5 - REPORTED CASES OF DHF IN THE AMERICAS, 1980-2007
First note that the scale here for the Americas is one-tenth that of what occurs in Southeast Asia. Although the absolute numbers are smaller, however, we are seeing the same pattern of increase in the Americas as has been seen in Asia. In the 1980s, the total number of cases was 15,000, and by the mid-1990s, through 1999, there were already about 56,000 cases. 

Change this text:  “DEN-3 has not yet spread to South America or many Caribbean islands. Its arrival in susceptible populations is expected to be followed by large outbreaks, as occurred in Central America in 1995.”

## Presence of DEN-3 in the Americas, 

- 1994 -2007

- SOURCE:  Pan American Health Organization – Nov. 30, 2007

## Recent Dengue in the U.S.A. 

- Dengue epidemics occurred in the USA in the 1800s and the first half of the 1900s
- Recent indigenous transmission
- Texas:
- 1980: 23 cases, first locally acquired since 1945
- 1986: 9 cases, 1995: 7 cases, 1997: 3 cases, 1998: 1 case, 1999: 18 cases, 2005: 25 cases
- Hawaii:
- 2001-2002: 122 cases (first since 1944)

## Seasonal Trends in Dengue Incidence: Puerto Rico

**Notes:**
SLIDE 57:  VI-3 - SEASONAL TRENDS IN DENGUE INCIDENCE
For persons living in dengue-endemic areas, the season of the year is an important consideration. Many areas of the world show seasonal transmission patterns, with peaks in incidence at certain times of year. This information helps determine the likelihood of a patients being infected with dengue.   As an example, this graph shows the curve of seasonality for the disease in Puerto Rico.  It shows that major epidemics occurred in 1994 and 1998, but also that the months of highest transmission in Puerto Rico are from July through January, which is also the warmer, rainier season. In other countries and regions, the time of year with peak transmission varies, but it is usually associated with the rainy season.

## Reinfestation by Aedes aegypti

-  1930s	         1970s                2006

**Notes:**
SLIDE 91:  VIII-3: REINFESTATION BY Aedes aegypti
Unfortunately, the success of the eradication campaign was not sustained. Beginning in the early 1970s, it began to be disbanded, and many countries channeled their limited resources into other areas. Consequently, Aedes aegypti began to reinfest the countries from which it had been eradicated. Comparing the 1970 with the 2006 map, we see the mosquito reestablishing itself throughout Central America and most of South America. As the mosquito has spread, the number and frequency of dengue epidemics have increased, as has dengue hemorrhagic fever activity in the Americas.