Search

Introduction: the Africa region was certified indigenous wild poliovirus-free in August 2020. Countries in East and Southern Africa have, during acute flaccid paralysis (AFP) and environmental surveillance (ES), detected equally concerning vaccine-derived polioviruses (VDPVs) that have not been systematically documented to guide programming in the sub-region. The study documents trends and salient observations of the VDPVs by country of detection, for 11 years from 2010 to 2021., Methods: we conducted secondary data analysis, a descriptive study design, by deploying field and laboratory of AFP and environmental surveillance databases of the 20 East and Southern African countries from 2010 to 2021., Results: a total of 318 VDPVs were reported over the study period. The majority were from AFP cases (58.8%) and the rest equally distributed between healthy community children and environmental surveillance sources. More polioviruses were detected after 2016 than during the period before. We observed that more boys were affected by VDPVs compared to girls. Children under 5 years were more affected than other age groups, with a mean age of 3.6 years. Delay of samples in the field seemed to increase the likelihood of not reporting VDPVs and not mounting timely public health detailed investigations and vaccination responses., Conclusion: the study provides useful evolutional trends of VDPVs for surveillance and vaccination programming. We also noted that the VDPV2s have been increasing after the 2016 tOPV to oral polio vaccine (bOPV) switch. The COVID-19 pandemic emergence in 2020, led to a decline in AFP, ES surveillance, and immunization activities. Our findings point to the need to implement enhanced tailored childhood immunization recovery strategies and to speed up the use of inactivated polio vaccine (IPV) to boost population immunity., Competing Interests: The authors declare no competing interests., (Copyright: Charles Byabamazima et al.)

Introduction: polio eradication initiatives started in 1988, this is almost the past 32 years following the WHA resolution 41.8 of eradicating polio by the year 2000. As of 2019, only 3 countries remained to be polio endemic globally, Afghanistan, Pakistan and Nigeria. The east and southern sub-region countries had shown progressive achievement towards polio eradication and to start with the African regional certification. The availability of sensitive AFP surveillance performance is among important strategies in the achievement of polio eradication. We, therefore, decided to conduct this assessment of AFP performance from 2012 to 2019 in the ESA sub-region have evidence documentation and support the certification process of the WHO AFRO region., Methods: we reviewed all reported acute flaccid paralysis (AFP) cases from 19 countries in the ESA sub region with the date of onset of paralysis from 1 January 2012 to 31 December 2019. The data were run to descriptive analysis based on the personal characteristics and AFP surveillance performance indicators parameters., Results: a total of 46,014 AFP cases were reported from 19 countries in the ESA countries who were paralyzed from 1 January 2012 to 31 December 2019. The most affected age group was children aged 0 to 3 years old where 19,740 children with acute paralysis were reported representing 42.9% of the total reported AFP for the period. The overall assessment of the non-polio AFP rate, there is an increase from a rate of 2.7 in 2012 to 3.5 in 2019 per 100,000 population aged less than 15 years, reflects a significant change with a p-value of 0.040 (95% C.I. ranges from 0.035 to 1.564). Furthermore, the percentage of stool adequacy raised from 86.4% in 2012 to 88.5% in 2019, with an observed 2.1% difference and no significant change over the 8 years., Conclusion: we observed an overall increase in the sensitivity of the AFP surveillance performance for the ESA sub-region countries from 2012 to 2019 using the national performance indicators. The COVID-19 pandemic paused an operational challenge for AFP surveillance performances from 2020. A further subnational surveillance performance analysis is suggested., Competing Interests: The authors declare no competing interests., (© Daudi Manyanga et al.)

Since the 1988 World Health Assembly resolution to eradicate poliomyelitis globally, substantial progress has been made in all World Health Organization (WHO) regions, and three regions (Americas, European, and Western Pacific) are classified as polio-free. The African Region comprises four epidemiologic blocks (Central, Eastern, Southern, and Western). The Southern African block comprises 14 countries--10 on the mainland (Angola, Botswana, Lesotho, Malawi, Mozambique, Namibia, South Africa, Swaziland, Zambia, and Zimbabwe) and four in the Indian Ocean (Comoros, Madagascar, Mauritius, and Seychelles)--with a combined total population in 2002 of approximately 120 million persons. This report summarizes polio eradication efforts in the Southern African block during January 2001-March 2003, which indicate the possible interruption of wild poliovirus (WPV) transmission and underscore the need to sustain polio eradication efforts.

During the 1990s, poliomyelitis transmission in 11 mainland and island nations of southern Africa appeared relatively low. However, the implementation of specific strategies recommended by the World Health Organization for eradicating polio in southern Africa began only in 1994. In 1995, oral poliovirus vaccine coverage (three doses) among infants was > or = 75% in all but 4 countries. National immunization days (NIDs) to control polio outbreaks were carried out in Namibia in 1994 and 1995. Angola, Botswana, and South Africa carried out subnational NIDs in 1995. All countries in southern Africa except Madagascar planned NIDs in 1996. Epidemiologic surveillance of acute flaccid paralysis (AFP) and laboratory surveillance of wild poliovirus was launched after nationwide training workshops in 7 mainland countries and is planned in the remaining countries by the end of 1996. Analysis of recommended performance indicators of AFP surveillance shows that substantial progress was made during 1994-1995, and the prospects for the certification of polio-free status in southern Africa on target appear good.

As part of emergency assistance to the Ministry of Health (MOH), national surveillance data for poliomyelitis and charts of cases at the national rehabilitation hospital were reviewed. Poliomyelitis patients admitted to Angola's main pediatric hospital were examined. A mean of 86 cases of poliomyelitis/year were reported in Angola during 1989-1994. Review of records from non-MOH sources uncovered another 74 cases, primarily from areas outside governmental control. Hospital chart reviews revealed that 80% of the cases were children <3 years of age, mainly unvaccinated. Molecular analyses of isolates from cases in Luanda and at the Angola-Namibia border suggest that these isolates are closely related and that > or = 2 strains of wild poliovirus type 1 are circulating currently in Angola. This investigation confirms that poliomyelitis has remained endemic in Angola since independence in 1975. It affects primarily young and unvaccinated children. Control of poliomyelitis in Angola is essential to expand the polio-free zone in southern Africa.

A key component of the global strategy to eradicate poliomyelitis by the year 2000 is surveillance for all cases of acute flaccid paralysis (AFP), ensuring the detection of cases of paralytic polio. During the 1990s, most of the countries of southern Africa (Table 1) have reported high (i.e., 70%-90%) levels of vaccination coverage among children aged < 1 year with three doses of oral poliovirus vaccine (OPV3). In addition, with the exception of Namibia, all of these countries have reported very low or zero incidence of polio (Table 1, Figure 1). To determine whether the low number of reported polio cases reflects the true incidence or underreporting, during 1992 and 1993 assessments of polio incidence and the quality of surveillance of suspected polio were conducted by teams consisting of national health officials, World Health Organization (WHO) staff and consultants, and representatives from Rotary International, using a standard protocol (1). This report summarizes the findings of assessments in Botswana, Lesotho, Malawi, South Africa, Swaziland, and Zimbabwe.