ABSTRACT
In October 2000,The ministries of health of the Dominican Republic and Haiti notified two cases of acute flaccid paralysis(AFP)in rural cases,one of them in a 9 year old female,respectively.Stool samples that were obtained from these cases,with ocured in July and August 2000,after a 9 year interruption of wild polivirus circulation in the western Hemisphere,revealed the presence of type 1 poliovirus.Genetic sequencing,wich was later performed at the centers for disease control and prevention,in Atlanta,Georgia,United States of America,revealed and atypical descendant of the virus used in the manufacture of the oral polio vaccine(OPV)but with 3 per cent genetic divergence with respect to the parent strain,Normally,viral isolates that derive from vaccine components show 99,5 per cent genetic agreement with the parent strain,in wild poliviruses,on the othe hand,this agreement is usually less tha 82,0 per cent.Thus,thw 3 per cent genetic divergence detected in this study suggests thar,in areas with low vaccine coveragemthe virus used in the vaccine remained in circulation for at least two years,during wich it recovered the neurovirulence and communicability of wild polivirus type 1.This report describes the characteristics and results of the active search for cases of AFP thar spaeked by the detection of the two indez cases.It also looks at the public health implications of this outbreak for the entire region of the Americas
Subject(s)
Humans , Female , Child, Preschool , Poliovirus Vaccine, Oral , PediatricsABSTRACT
In some countries, the invasive disease caused by Haemophilus influenzae type b (Hib) has been practically eliminated thanks to vaccination. However, in much of the developing world, meningitides and pneumonias caused by these bacteria continue to be a major cause of childhood morbidity and mortality, as well as high hospitalization costs. Because safe and effective conjugate vaccines are now available, the Special Program for Vaccines and Immunization of the Pan American Health Organization has recommended introducting them into the regular vaccination regimen of as many countries as possible. This has been done in Chile and Uruguay, where the Hib vaccine now forms part of the regular vaccination routine. When the vaccine was being introduced, both countries had difficulties they could have avoided if they had known of the experiences of other nations. Therefore, these two countries now offer the lessons they learned to other nations considering introducing the vaccine into their immunization programs. The most important lessons were to: strengthen the epidemiological surveillance system sufficiently in advance of introducing the vaccine; with the support of scientific societies, present the technical information that justifies introducing the vaccine; seek community baking and acceptance; precisely establish in advance the presentation and dosage of the vaccine that is most appropriate for the country; and be certain to have the political and legal decisions needed to ensure the continuity of Hib vaccination in the future