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The reliable and timely detection of poliovirus infection through surveillance for acute flaccid paralysis (AFP), supplemented by environmental surveillance (ES) of sewage samples, is a critical component of the polio eradication programme. Since 1988, the number of polio cases caused by wild poliovirus (WPV) has decreased by >99.9%, and eradication of WPV serotypes 2 and 3 has been certified; only serotype 1 (WPV1) continues to circulate and transmission remains endemic in Afghanistan and Pakistan. In this surveillance update, we evaluated indicators of AFP in surveillance, ES for polioviruses and data on the performance of the Global Polio Laboratory Network (GPLN) provided by 28 priority countries for the programme during 2022-2023. No WPV1 cases have been detected outside those countries since August 2022, when importation into Malawi and Mozambique resulted in an outbreak during 2021-2022. During 2022-2023, 20 of 28 priority countries (71.4%) met national AFP surveillance indicator targets, and the number of ES sites increased. Low national rates of reported AFP cases in priority countries in 2023 might have been due to lags in surveillance reporting; substantial national and subnational AFP surveillance gaps persist. Maintaining high-quality surveillance is critical to achieving the goal of global polio eradication. Monitoring surveillance indicators is important to identifying gaps and guiding surveillance-strengthening activities, particularly in countries at high risk for poliovirus circulation. La detection fiable et rapide de l'infection a poliovirus au moyen de la surveillance de la paralysie flasque aigue (PFA), completee par une surveillance des echantillons d'eaux usees, est un element essentiel du programme d'eradication de la poliomyelite. Depuis 1988, le nombre de cas de poliomyelite dus au poliovirus sauvage (PVS) a diminue de >99,9% et l'eradication des serotypes 2 et 3 du PVS a ete certifiee; seul le serotype 1 du poliovirus sauvage (PVS1) continue de circuler et la transmission demeure endemique en Afghanistan et au Pakistan. Dans ce rapport faisant le point sur la surveillance, nous evaluons les indicateurs de la PFA a des fins de surveillance pour la recherche des poliovirus et les donnees relatives aux performances du Reseau mondial de laboratoires pour la poliomyelite (RMLP) communiquees par les 28 pays prioritaires pour le programme en 2022-2023. Aucun cas du au PVS1 n'a ete detecte en dehors de ces pays depuis aout 2022, apres une flambee epidemique en 2021-2022 due a l'importation du virus au Malawi et au Mozambique. En 2022-2023, 20 des 28 pays prioritaires (71,4 %) ont atteint les cibles des indicateurs de surveillance de la PFA, et le nombre de sites de surveillance environnementale a augmente. Le faible nombre de cas de PFA signales dans les pays prioritaires en 2023 pourrait etre du a des retards dans la communication des donnees issues de la surveillance; d'importantes lacunes en matiere de surveillance de la PFA a l'echelle nationale et infranationale persistent. Il est essentiel de maintenir une surveillance de qualite afin d'atteindre l'eradication de la poliomyelite a l'echelle mondiale. Un suivi des indicateurs de surveillance est egalement important pour identifier les lacunes et orienter les activites de surveillance, particulierement dans les pays oU il existe un risque eleve de circulation du poliovirus., Introduction Since the Global Polio Eradication Initiative (GPEI) was established in 1988, the number of WPV cases has decreased by >99.9%, and WPV serotypes 2 and 3 have been declared [...]

Since the Global Polio Eradication Initiative was established in 1988, the number of cases due to wild poliovirus (WPV) has decreased by >99.9%, and WPV serotypes 2 and 3 have [...]

Since the World Health Assembly established the Global Polio Eradication Initiative (GPEI) in 1988, 2 of the 3 wild poliovirus (WPV) serotypes (types 2 and 3) have been eradicated, and [...]

In 1988, the World Health Assembly established the Global Polio Eradication Initiative (GPEI). Since then, wild poliovirus (WPV) cases have decreased approximately 99.99%, and WPV types 2 and 3 have [...]

In 1988, when the Global Polio Eradication Initiative (GPEI) began, polio paralyzed >350 000 children across 125 countries. Today, only 1 of 3 wild poliovirus serotypes, type 1 (WPV1), remains [...]

Since the Global Polio Eradication Initiative (GPEI) was established in 1988, 2 of the 3 wild poliovirus (WPV) serotypes (types 2 and 3) have been eradicated. (1) Transmission of WPV [...]

Circulating vaccine-derived polioviruses (cVDPVs) can emerge in areas with low poliovirus immunity and cause outbreaks (1) of paralytic polio. (2-6) Of the 3 types of wild poliovirus, type 2 was [...]

The reliable and timely detection of poliovirus cases through surveillance for acute flaccid paralysis (AFP), supplemented by environmental surveillance of sewage samples, is a critical component of the polio eradication program. Since 1988, the number of polio cases caused by wild poliovirus (WPV) has declined by >99.9%, and eradication of WPV serotypes 2 and 3 has been certified; only serotype 1 (WPV1) continues to circulate, and transmission remains endemic in Afghanistan and Pakistan. This surveillance update evaluated indicators from AFP surveillance, environmental surveillance for polioviruses, and Global Polio Laboratory Network performance data provided by 28 priority countries for the program during 2022-2023. No WPV1 cases have been detected outside of Afghanistan and Pakistan since August 2022, when an importation into Malawi and Mozambique resulted in an outbreak during 2021-2022. During 2022-2023, among 28 priority countries, 20 (71.4%) met national AFP surveillance indicator targets, and the number of environmental surveillance sites increased. However, low national rates of reported AFP cases in priority countries in 2023 might have resulted from surveillance reporting lags; substantial national and subnational AFP surveillance gaps persist. Maintaining high-quality surveillance is critical to achieving the goal of global polio eradication. Monitoring surveillance indicators is important to identifying gaps and guiding surveillance-strengthening activities, particularly in countries at high risk for poliovirus circulation. [ABSTRACT FROM AUTHOR]

The last cases of poliomyelitis in Papua New Guinea (PNG) were reported in 1996; PNG is one of 37 countries or areas of the WHO Western Pacific Region that was [...]

In 1988, the World Health Assembly (WHA) resolved to eradicate polio worldwide. In 2015, only Afghanistan and Pakistan have reported wild poliovirus (WPV) transmission. (1) Timely steps are needed for [...]

Objective: To investigate and ascertain the source of a nursing home outbreak of gastroenteritis in Melbourne in 1997. Method: A retrospective cohort study. We obtained fecal and food samples and environmental swabs, and reviewed food handling. Results: There were 25 cases, and 21 of these had their meals pureed (liquidised). The relative risk for eating pureed food and becoming ill was 5.8 (95% CI 2.2-15.4). Clostridium perfringens and its enterotoxin was detected in nine fecal samples. Sample of pureed food tested positive for coliforms. Conclusions: This outbreak was cause by C. perfringens contaminating pureed food. Food liquidising provides opportunities for re-contamination of cooked food through the use of contaminated equipment and deficiencies in food handling practices. Pureed foods should be reheated to 70 decrees C after liquidising to inactive pathogens. Implications: Health care facilities need to make specific precautions to manage the special hazards involved in preparing pureed food.

Background: The international spread of wild poliomyelitis outbreaks continues to threaten eradication of poliomyelitis and in 2014 a public health emergency of international concern was declared. Here we describe a risk scoring system that has been used to assess country-level risks of wild poliomyelitis outbreaks, to inform prioritisation of mass vaccination planning, and describe the change in risk from 2014 to 2016. The methods were also used to assess the risk of emergence of vaccine-derived poliomyelitis outbreaks.Methods: Potential explanatory variables were tested against the reported outbreaks of wild poliomyelitis since 2003 using multivariable regression analysis. The regression analysis was translated to a risk score and used to classify countries as Low, Medium, Medium High and High risk, based on the predictive ability of the score.Results: Indicators of population immunity, population displacement and diarrhoeal disease were associated with an increased risk of both wild and vaccine-derived outbreaks. High migration from countries with wild cases was associated with wild outbreaks. High birth numbers were associated with an increased risk of vaccine-derived outbreaks.Conclusions: Use of the scoring system is a transparent and rapid approach to assess country risk of wild and vaccine-derived poliomyelitis outbreaks. Since 2008 there has been a steep reduction in the number of wild poliomyelitis outbreaks and the reduction in countries classified as High and Medium High risk has reflected this. The risk of vaccine-derived poliomyelitis outbreaks has varied geographically. These findings highlight that many countries remain susceptible to poliomyelitis outbreaks and maintenance or improvement in routine immunisation is vital. [ABSTRACT FROM AUTHOR]

Concurrent outbreaks of circulating vaccine-derived poliovirus serotypes 1 and 2 (cVDPV1, cVDPV2) were confirmed in the Republic of the Philippines in September 2019 and were subsequently confirmed in Malaysia by early 2020. There is continuous population subgroup movement in specific geographies between the two countries. Outbreak response efforts focused on sequential supplemental immunization activities with monovalent Sabin strain oral poliovirus vaccine type 2 (mOPV2) and bivalent oral poliovirus vaccines (bOPV, containing Sabin strain types 1 and 3) as well as activities to enhance poliovirus surveillance sensitivity to detect virus circulation. A total of six cVDPV1 cases, 13 cVDPV2 cases, and one immunodeficiency-associated vaccine-derived poliovirus type 2 case were detected, and there were 35 cVDPV1 and 31 cVDPV2 isolates from environmental surveillance sewage collection sites. No further cVDPV1 or cVDPV2 have been detected in either country since March 2020. Response efforts in both countries encountered challenges, particularly those caused by the global COVID-19 pandemic. Important lessons were identified and could be useful for other countries that experience outbreaks of concurrent cVDPV serotypes. [ABSTRACT FROM AUTHOR]

The purpose of the present paper was to determine recent patterns of hepatitis C virus (HCV) transmission in Australia through a national system of enhanced surveillance of newly acquired hepatitis C. Demographic, clinical, and risk behavior information on newly acquired hepatitis C cases from 1997 to 2000 was collected. Newly acquired hepatitis C included cases of HCV antibody sero-conversion within a 12 month period and acute clinical hepatitis C cases. Nine hundred and twelve cases of newly acquired hepatitis C were identified, representing 2.8% of all HCV notifications for this period. The majority of cases (72%) were diagnosed in people aged between 20 and 39 years. Injecting drug use was reported in the vast majority of cases (93%), with sexual transmission (2%) and tattooing (2%) reported in small numbers. HCV antibody sero-conversion was the mode of diagnosis in most cases (78%). Injecting drug use is the main route of HCV transmission in Australia. As only a small proportion of HCV infections are detected as newly acquired, enhanced surveillance procedures, including increased regular HCV testing of at-risk populations are required to more effectively monitor recent patterns of transmission. © 2004 Blackwell Publishing Asia Pty Ltd [ABSTRACT FROM AUTHOR]

The global withdrawal of trivalent oral poliovirus vaccine (OPV) (tOPV, containing Sabin poliovirus strains serotypes 1, 2 and 3) from routine immunization, and the introduction of bivalent OPV (bOPV, containing Sabin poliovirus strains serotypes 1 and 3) and trivalent inactivated poliovirus vaccine (IPV) into routine immunization was expected to improve population serologic and mucosal immunity to types 1 and 3 poliovirus, while population mucosal immunity to type 2 poliovirus would decline. However, over the period since tOPV withdrawal, the implementation of preventive bOPV supplementary immunization activities (SIAs) has decreased, while outbreaks of type 2 circulating vaccine derived poliovirus (cVDPV2) have required targeted use of monovalent type 2 OPV (mOPV2). We develop a dynamic model of OPV-induced immunity to estimate serotype-specific, district-level immunity for countries in priority regions and characterize changes in immunity since 2016. We account for the changes in routine immunization schedules and varying implementation of preventive and outbreak response SIAs, assuming homogenous coverages of 50% and 80% for SIAs. In areas with strong routine immunization, the switch from tOPV to bOPV has likely resulted in gains in population immunity to types 1 and 3 poliovirus. However, we estimate that improved immunogenicity of new schedules has not compensated for declines in preventive SIAs in areas with weak routine immunization. For type 2 poliovirus, without tOPV in routine immunization or SIAs, mucosal immunity has declined nearly everywhere, while use of mOPV2 has created highly heterogeneous population immunity for which it is important to take into account when responding to cVDPV2 outbreaks. The withdrawal of tOPV and declining allocations of resources for preventive bOPV SIAs have resulted in reduced immunity in vulnerable areas to types 1 and 3 poliovirus and generally reduced immunity to type 2 poliovirus in the regions studied, assuming homogeneous coverages of 50% and 80% for SIAs. The very low mucosal immunity to type 2 poliovirus generates substantially greater risk for further spread of cVDPV2 outbreaks. Emerging gaps in immunity to all serotypes will require judicious targeting of limited resources to the most vulnerable populations by the Global Polio Eradication Initiative (GPEI). [ABSTRACT FROM AUTHOR]

Since the Global Polio Eradication Initiative (GPEI) was established in 1988, the number of wild poliovirus (WPV) cases has declined by >99.9%, and WPV serotypes 2 and 3 have been declared eradicated (1). By the end of 2022, WPV type 1 (WPV1) transmission remained endemic only in Afghanistan and Pakistan (2,3). However, during 2021-2022, Malawi and Mozambique reported nine WPV1 cases that were genetically linked to Pakistan (4,5), and circulating vaccine-derived poliovirus (cVDPV) outbreaks were detected in 42 countries (6). cVDPVs are oral poliovirus vaccine-derived viruses that can emerge after prolonged circulation in populations with low immunity allowing reversion to neurovirulence and can cause paralysis. Polioviruses are detected primarily through surveillance for acute flaccid paralysis (AFP), and poliovirus is confirmed through stool specimen testing. Environmental surveillance, the systematic sampling of sewage and testing for the presence of poliovirus, supplements AFP surveillance. Both surveillance systems were affected by the COVID-19 pandemic's effects on public health activities during 2020 (7,8) but improved in 2021 (9). This report updates previous reports (7,9) to describe surveillance performance during 2021-2022 in 34 priority countries.* In 2022, a total of 26 (76.5%) priority countries met the two key AFP surveillance performance indicator targets nationally compared with 24 (70.6%) countries in 2021; however, substantial gaps remain in subnational areas. Environmental surveillance expanded to 725 sites in priority countries, a 31.1% increase from the 553 sites reported in 2021. High-quality surveillance is critical to rapidly detect poliovirus transmission and enable prompt poliovirus outbreak response to stop circulation. Frequent monitoring of surveillance guides improvements to achieve progress toward polio eradication., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.

Since the World Health Assembly established the Global Polio Eradication Initiative (GPEI) in 1988, two of the three wild poliovirus (WPV) serotypes (types 2 and 3) have been eradicated, and global WPV cases have decreased by more than 99.9%. Afghanistan and Pakistan remain the only countries where indigenous WPV type 1 (WPV1) transmission has not been interrupted. This report summarizes progress toward global polio eradication during January 1, 2021-March 31, 2023, and updates previous reports (1,2). In 2022, Afghanistan and Pakistan reported 22 WPV1 cases, compared with five in 2021; as of May 5, 2023, a single WPV1 case was reported in Pakistan in 2023. A WPV1 case was reported on the African continent for the first time since 2016, when officials in Malawi confirmed a WPV1 case in a child with paralysis onset in November 2021; neighboring Mozambique subsequently reported eight genetically linked cases. Outbreaks of polio caused by circulating vaccine-derived polioviruses (cVDPVs) can occur when oral poliovirus vaccine (OPV) strains circulate for a prolonged time in underimmunized populations, allowing reversion to neurovirulence (3). A total of 859 cVDPV cases occurred during 2022, an increase of 23% from 698 cases in 2021. cVDPVs were detected in areas where poliovirus transmission had long been eliminated (including in Canada, Israel, the United Kingdom, and the United States). In addition, cocirculation of multiple poliovirus types occurred in multiple countries globally (including Democratic Republic of the Congo [DRC], Israel, Malawi, Mozambique, Republic of the Congo, and Yemen). The 2022-2026 GPEI strategic plan targeted the goal of detecting the last cases of WPV1 and cVDPV in 2023 (4). The current global epidemiology of poliovirus transmission makes the likelihood of meeting this target date unlikely. The detections of poliovirus (WPV1 and cVDPVs) in areas where it had been previously eliminated underscore the threat of continued poliovirus spread to any area where there is insufficient vaccination to poliovirus (3). Mass vaccination and surveillance should be further enhanced in areas of transmission to interrupt poliovirus transmission and to end the global threat of paralytic polio in children., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.

In 1988, the World Health Assembly established the Global Polio Eradication Initiative (GPEI). Since then, wild poliovirus (WPV) cases have decreased approximately 99.99%, and WPV types 2 and 3 have been declared eradicated. Only Afghanistan and Pakistan have never interrupted WPV type 1 (WPV1) transmission. This report describes global progress toward polio eradication during January 1, 2020-April 30, 2022, and updates previous reports (1,2). This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy.* Five WPV1 cases were reported from Afghanistan and Pakistan in 2021, compared with 140 in 2020. In 2022 (as of May 5), three WPV1 cases had been reported: one from Afghanistan and two from Pakistan. WPV1 genetically linked to virus circulating in Pakistan was identified in Malawi in a child with paralysis onset in November 2021. Circulating vaccine-derived polioviruses (cVDPVs), with neurovirulence and transmissibility similar to that of WPV, emerge in populations with low immunity following prolonged circulation of Sabin strain oral poliovirus vaccine (OPV) (3). During January 2020-April 30, 2022, a total of 1,856 paralytic cVDPV cases were reported globally: 1,113 in 2020 and 688 in 2021, including cases in Afghanistan and Pakistan. In 2022 (as of May 5), 55 cVDPV cases had been reported. Intensified programmatic actions leading to more effective outbreak responses are needed to stop cVDPV transmission. The 2022-2026 GPEI Strategic Plan objective of ending WPV1 transmission by the end of 2023 is attainable (4). However, the risk for children being paralyzed by polio remains until all polioviruses, including WPV and cVDPV, are eradicated., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.

In 1988, when the Global Polio Eradication Initiative (GPEI) began, polio paralyzed >350,000 children across 125 countries. Today, only one of three wild poliovirus serotypes, type 1 (WPV1), remains in circulation in only two countries, Afghanistan and Pakistan. This report summarizes progress toward global polio eradication during January 1, 2019-June 30, 2021 and updates previous reports (1,2). In 2020, 140 cases of WPV1 were reported, including 56 in Afghanistan (a 93% increase from 29 cases in 2019) and 84 in Pakistan (a 43% decrease from 147 cases in 2019). As GPEI focuses on the last endemic WPV reservoirs, poliomyelitis outbreaks caused by circulating vaccine-derived poliovirus (cVDPV) have emerged as a result of attenuated oral poliovirus vaccine (OPV) virus regaining neurovirulence after prolonged circulation in underimmunized populations (3). In 2020, 32 countries reported cVDPV outbreaks (four type 1 [cVDPV1], 26 type 2 [cVDPV2] and two with outbreaks of both); 13 of these countries reported new outbreaks. The updated GPEI Polio Eradication Strategy 2022-2026 (4) includes expanded use of the type 2 novel oral poliovirus vaccine (nOPV2) to avoid new emergences of cVDPV2 during outbreak responses (3). The new strategy deploys other tactics, such as increased national accountability, and focused investments for overcoming the remaining barriers to eradication, including program disruptions and setbacks caused by the COVID-19 pandemic., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.

Since the Global Polio Eradication Initiative (GPEI) was established in 1988, two of the three wild poliovirus (WPV) serotypes (types 2 and 3) have been eradicated.* Transmission of WPV type 1 (WPV1) remains uninterrupted only in Afghanistan and Pakistan. This report summarizes progress toward global polio eradication during January 1, 2018-March 31, 2020 and updates previous reports (1,2). In 2019, Afghanistan and Pakistan reported the highest number of WPV1 cases (176) since 2014. During January 1-March 31, 2020 (as of June 19), 54 WPV1 cases were reported, an approximate fourfold increase from 12 cases during the corresponding period in 2019. Paralytic poliomyelitis can also be caused by circulating vaccine-derived poliovirus (cVDPV), which emerges when attenuated oral poliovirus vaccine (OPV) virus reverts to neurovirulence following prolonged circulation in underimmunized populations (3). Since the global withdrawal of type 2-containing OPV (OPV2) in April 2016, cVDPV type 2 (cVDPV2) outbreaks have increased in number and geographic extent (4). During January 2018-March 2020, 21 countries reported 547 cVDPV2 cases. Complicating increased poliovirus transmission during 2020, the coronavirus disease 2019 (COVID-19) pandemic and mitigation efforts have resulted in suspension of immunization activities and disruptions to poliovirus surveillance. When the COVID-19 emergency subsides, enhanced support will be needed to resume polio eradication field activities., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.

Circulating vaccine-derived polioviruses (cVDPVs) can emerge in areas with low poliovirus immunity and cause outbreaks* of paralytic polio (1-5). Among the three types of wild poliovirus, type 2 was declared eradicated in 2015 (1,2). The use of trivalent oral poliovirus vaccine (tOPV; types 1, 2, and 3 Sabin strains) ceased in April 2016 via a 1-month-long, global synchronized switch to bivalent OPV (bOPV; types 1 and 3 Sabin strains) in immunization activities (1-4). Monovalent type 2 OPV (mOPV2; type 2 Sabin strain) is available for cVDPV type 2 (cVDPV2) outbreak response immunization (1-5). The number and geographic breadth of post-switch cVDPV2 outbreaks have exceeded forecasts that trended toward zero outbreaks 4 years after the switch and assumed rapid and effective control of any that occurred (4). New cVDPV2 outbreaks have been seeded by mOPV2 use, by both suboptimal mOPV2 coverage within response zones and recently mOPV2-vaccinated children or contacts traveling outside of response zones, where children born after the global switch are fully susceptible to poliovirus type 2 transmission (2-4). In addition, new emergences can develop by inadvertent exposure to Sabin OPV2-containing vaccine (i.e., residual response mOPV2 or tOPV) (4). This report updates the January 2018-June 2019 report with information on global cVDPV outbreaks during July 2019-February 2020 (as of March 25, 2020) † (2). Among 33 cVDPV outbreaks reported during July 2019-February 2020, 31 (94%) were cVDPV2; 18 (58%) of these followed new emergences. In mid-2020, the Global Polio Eradication Initiative (GPEI) plans to introduce a genetically stabilized, novel OPV type 2 (nOPV2) that has a lower risk for generating VDPV2 than does Sabin mOPV2; if nOPV2 is successful in limiting new VDPV2 emergences, GPEI foresees the replacement of Sabin mOPV2 with nOPV2 for cVDPV2 outbreak responses during 2021 (2,4,6)., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.