United States Centers for Disease Control and Prevention. MMWR. 3 May 2013. 62(17):335–338.
Available at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6217a4.htm
Excerpt. In May 2012, the World Health Assembly of the World Health Organization (WHO) declared the completion of polio eradication a programmatic emergency. Since the launch of the Global Polio Eradication Initiative (GPEI) in 1988, the number of annual polio cases has decreased by >99%. As of March 2013, circulation of indigenous wild poliovirus (WPV) continued in only three countries: Afghanistan, Nigeria, and Pakistan (the last case in India had onset in January 2011). This report provides an update on progress toward global polio eradication during January 2011–March 2013, using data reported as of April 23, 2013. The number of WPV cases reported globally decreased 66%, from 650 in 2011 to 223 in 2012; WPV cases decreased 53% (from 80 to 37) in Afghanistan and 71% (from 198 to 58) in Pakistan, but increased 97% (from 62 to 122) in Nigeria. The number of imported WPV cases in previously polio-free countries decreased from 309 in 12 countries in 2011 to six in two countries in 2012. During January–March 2013, a total of 22 WPV cases were reported worldwide, compared with 48 cases during the same period in 2012. An estimated 2.05 billion doses of oral poliovirus vaccine (OPV) were administered in 2012 to approximately 448 million persons, primarily children aged <5 years, in supplemental immunization activities (SIAs) conducted in 46 countries. SIAs were temporarily suspended in areas of Pakistan and Nigeria after attacks against health workers occurred in December 2012 and the first quarter of 2013. The number of confirmed WPV cases has decreased to the lowest level ever, but security concerns continue to threaten the overall goal of global eradication.
Wild poliovirus has been found in samples taken from sewage in Al Haggana (Nasr City) and Al Salam district in Cairo. The wild poliovirus is related to the wild poliovirus type 1, from north Sindh, Pakistan, which was reported in September 2012.
This is the first documented importation of wild poliovirus from Pakistan, after Egypt was declared polio free, with its last case in May 2004. At this stage, there are no cases (children) of paralysis associated with this importation.
These poliovirus strains have been detected through ongoing environmental surveillance in Egypt, which involves regular testing of sewage water from multiple sites (total in the country 34, in Cairo 5).
Emergency response and coordination efforts are ongoing between the Ministry of Health and Population, the Government of Egypt and the Global Polio Eradication Initiative partners, WHO and UNICEF. Teams have been sent to each of the areas in which the virus was detected in environmental sampling and a field investigation and active search for cases is ongoing. The frequency of environmental sampling has been increased; environmental samples will be collected fortnightly instead of monthly from the five sites located in Cairo.
Supplementary immunization activities are being planned for a large-scale Cairo-wide campaign for children under 5 years of age, targeting approximately 3 million children. The campaign is planned during the coming month; dates have not yet been finalized. Immediate response vaccination in these two areas has been strongly recommended to the Ministry of Health and Population.
Meanwhile, in a joint statement, WHO, UNICEF and the Polio Monitoring Cell in Pakistan have announced this situation as critical and alarming for the polio programme in Pakistan. The statement further adds that children under the age of five departing Pakistan will be given polio drops at special counters at the airports.
Lai FY, Thoon KC, Ang LW, et al. Vaccine. 1 April 2012. doi:10.1016/j.vaccine.2012.03.059.
Available at http://www.sciencedirect.com/science/article/pii/S0264410X12004513
Background. We assessed the seroepidemiology of pertussis, diphtheria and poliovirus antibodies in a cohort of highly immunized children, together with the burden of these diseases in Singapore.
Methods. Hospital residual sera collected between August 2008 and July 2010 from 1200 children aged 1–17 years were tested for the prevalence of IgG antibodies against Bordetella pertussis, diphtheria toxoid, and all three poliovirus types by enzyme-linked immunosorbent assays.
Results. We found an overall seroprevalence of 99.4% (95% CI 98.8–99.7%) for diphtheria, and 92.3% (95% CI 90.6–93.6%) for poliomyelitis, along with no indigenous cases of these diseases since 1993. However, the seroprevalence for pertussis was 60.8% (95% CI 58.0–63.5%) only. Among the subjects who had completed three doses of pertussis vaccination by the age of 2 years (n=1092), the pertussis seroprevalence was 85.0% (95% CI 79.7–89.2%) in those who received the last vaccination within a year before the study, and it decreased to 75.0% (95% CI 64.5–83.2%) and 63.1% (95% CI 50.9–73.8%) in those who had the last vaccination 1 year and 2 years before the study, respectively. The seroprevalence remained at about 50% for those whose last pertussis vaccination was administered 4 years and longer before the study.
Conclusions. The high seroprevalence for poliomyelitis and diphtheria confer solid herd immunity to eliminate these diseases in Singapore. In contrast, immunity against pertussis waned considerably over time, and routine boosters should be given to adolescents to ensure sustained immunity against pertussis.