Recorded presentation

Ying Guo¹, Yi Wang¹, and Qing-Tang Li². (1) Center for Disease Control and Prevention, Office of Disease Control & Public Awareness, Yuzhou, 461670, China, 86-0374-8184252, guohealth@yahoo.com, (2) Public Health Bureau, City of Yuzhou, Yuzhou, 461670, China

Background: Our knowledge is limited on outbreak control activities during measles outbreaks in developing countries (Aylward, Clements, and Olive, 1997). How would the use of the different outbreak immunization strategies affect vaccination effectiveness during outbreaks? How would other contextual factors affect vaccination effectiveness in such settings?

Methods: Two independent measles outbreaks in Yuzhou, China were studied. One outbreak occurred in 2001 in a community with low vaccination coverage, while the other outbreak occurred in 2003 in a community with high vaccination coverage. A selective immunization strategy was used in the vaccination campaign during the former outbreak, whereas a non-selective immunization strategy was used during the latter outbreak.

Results: During the first outbreak, measles occurred in 20 of the 249 children during and after the vaccination campaign. The attack rate among unvaccinated children was 8.5% (12 of 141), compared with 7.4% (8 of 108) among those vaccinated. During the second outbreak, no measles occurred in the 783 (0.0%) vaccinated children during and after the vaccination campaign. The results indicate that the use of the non-selective immunization strategy might lead to higher vaccination effectiveness. In addition, children’s previous vaccination history and delays in the notification of measles cases might also play a role in determining vaccination effectiveness.

Conclusions: The study contributes to accumulating the empirical knowledge of outbreak control activities in developing countries. The findings suggest that public health professionals continue to evaluate the effectiveness of different outbreak immunization strategies in such settings and take measures to address various contextual factors.

Learning Objectives: At conclusion of the session, participants will be able to

• Identify major measles outbreak control strategies used in developing countries (e.g., China);
• Assess the impacts of different outbreak control strategies on vaccination effectiveness during outbreaks in such settings; and
• List various contextual factors that may also affect vaccination effectiveness, as well as identify possible solutions to address these factors.

Keywords: Outbreaks, Developing Countries

Presenting author's disclosure statement:
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.

Recorded presentation