Epidemiology of Diptheria

 

 

Whoís at risk?

 

• Unimmunized adults
• Inadequately immunized adults older persons
• Persons of Native American background
• Persons of lower economic strata

 

How many cases per year?

 

• United States:
• From 1980-1999 only 49 cases (average of 3 cases per year)

 

Prevalence of infection

 

ÝÝÝÝÝÝÝÝÝÝÝ Generally worldwide:

…         More prevalent in temperate zones

…         outbreak of diptheria began in 1990 in the Russian Federation

…         by 1994, all 15 Newly Independent States were affected

…         > 50,000 cases and 1,500 deaths in 1995 alone

…         mostly adult were infected

 

ÝÝÝÝÝÝÝÝÝÝÝ United States:

…         in the southeast during the winter time

…         highest incidence rates have been in states with a significant population of Native Americans

…         no geographic concentration of cases s currently observed

 

…         Of the 49 cases of diptheria observed from 1980-1999, 40 cases were reported with known age

ÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ 63% were in persons > 20 years of age

ÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ 38% were in persons > 40 years of age

(most cases occurred in unimmunized or inadequately immunized persons)

 

Trends in the United States

 

ÝÝÝÝÝÝÝÝÝÝÝ In the 1920s, 100,000-200,000 cases of diptheria (140-150 cases per 100,000 population) and 13,000-15000 deaths were reported each year. The number of cases gradually fell to about 19,000 in 1945 (15 cases per 100,000 population). A more rapid decrease began with the introduction and use of toxoid in the late 1940s.

ÝÝÝÝÝÝÝÝÝÝÝ From 1970-1979 an average of 196 cases per year were reported. And from 1980-1999, only 49 cases were reported in the United States (an average of 3 per year).

 

Vaccination schedule

 

I.        Routine DTaP Primary Vaccination Schedule

 

ÝÝÝÝÝÝÝÝÝÝÝ DoseÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ AgeÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ Interval

ÝÝÝÝÝÝÝÝÝÝÝ primary 1ÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ 2moÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ ---------

ÝÝÝÝÝÝÝÝÝÝÝ primary2ÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ 4moÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ 4wks

ÝÝÝÝÝÝÝÝÝÝÝ primary3ÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ 6moÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ 4wks

ÝÝÝÝÝÝÝÝÝÝÝ primary4ÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ 15-18mosÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ 6mos

 

ÝÝÝÝÝÝÝÝÝÝÝ

II.      Routine DTaP Schedule (children <7 yrs of age)

 

…         4-6 years, before entering school

…         11-16 years of age if >5 years since last dose (Td)

…         every 10 years thereafter (Td)

 

 

III.    Routine Td Schedule (persons >7 yrs of age)

 

ÝÝÝÝÝÝÝÝÝÝÝ DoseÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ Interval

ÝÝÝÝÝÝÝÝÝÝÝ primary1ÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ --------

ÝÝÝÝÝÝÝÝÝÝÝ primary2ÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ 4wks

ÝÝÝÝÝÝÝÝÝÝÝ primary3ÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝÝ 6-12mosÝÝÝÝÝÝÝÝÝ

 

…        booster dose every 10 yrs