Correction: Community engagement to increase vaccine uptake: Quasi-experimental evidence from Islamabad and Rawalpindi, Pakistan.

[This corrects the article DOI: 10.1371/journal.pone.

Exploring the path to polio eradication: insights from consecutive seroprevalence surveys among Pakistani children.

Introduction: After trivalent oral poliovirus vaccine (tOPV) cessation, Pakistan has maintained immunity to type 2 poliovirus by administering inactivated polio vaccine (IPV) in routine immunization, alongside monovalent OPV type 2 (mOPV2) and IPV in supplementary immunization activities (SIAs). This study assesses the change in poliovirus type 2 immunity after tOPV withdrawal and due to SIAs with mOPV2 and IPV among children aged 6-11 months.

Methods: Three cross-sectional sequential serological surveys were conducted in 12 polio high-risk areas of Pakistan.

Progress Toward Poliomyelitis Eradication - Pakistan, January 2022-June 2023.

Since the establishment of the Global Polio Eradication Initiative in 1988, Pakistan remains one of only two countries (along with Afghanistan) with continued endemic transmission of wild poliovirus (WPV). This report describes Pakistan's progress toward polio eradication during January 2022-June 2023. During 2022, Pakistan reported 20 WPV type 1 (WPV1) cases, all of which occurred within a small geographic area encompassing three districts in south Khyber Pakhtunkhwa.

COVID-19 vaccination acceptance in underserved urban areas of Islamabad and Rawalpindi: results from a cross-sectional survey.

Background: Urban slums are home to a significant number of marginalized individuals and are often excluded from public services. This study explores the determinants of willingness and uptake of COVID-19 vaccines in urban slums in Pakistan.

Methods: The study uses a cross-sectional survey of 1760 respondents from five urban slums in twin cities of Rawalpindi and Islamabad carried out between June 16 and 26, 2021.

Community engagement to increase vaccine uptake: Quasi-experimental evidence from Islamabad and Rawalpindi, Pakistan.

Developing countries have been facing difficulties in reaching out to low-income and underserved communities for COVID-19 vaccination coverage. The rapidity of vaccine development caused a mistrust among certain subgroups of the population, and hence innovative approaches were taken to reach out to such populations. Using a sample of 1760 respondents in five low-income, informal localities of Islamabad and Rawalpindi, Pakistan, we evaluated a set of interventions involving community engagement by addressing demand and access barriers.

Modelling the spread of serotype-2 vaccine derived-poliovirus outbreak in Pakistan and Afghanistan to inform outbreak control strategies in the context of the COVID-19 pandemic.

Background: Since July 2019, Pakistan and Afghanistan have been facing an outbreak of serotype-2 circulating vaccine derived poliovirus (cVDPV2) in addition to continued transmission of serotype-1 wild poliovirus (WPV1) and SARS-CoV-2 in 2020. Understanding the risks of cVDPV2 transmission due to pause of global vaccination efforts and the impact of potential vaccination response strategies in the current context of COVID-19 mitigation measures is critical.

Methods: We developed a stochastic, geographically structured mathematical model of cVDPV2 transmission which captures both mucosal and humoral immunity separately and allows for reversion of serotype-2 oral polio vaccine (OPV2) virus to cVDPV2 following vaccine administration.

Detection of SARs-CoV-2 in wastewater using the existing environmental surveillance network: A potential supplementary system for monitoring COVID-19 transmission.

The ongoing COVID-19 pandemic is caused by SARs-CoV-2. The virus is transmitted from person to person through droplet infections i.e.

Use of public health emergency operations center (PH-EOC) and adaptation of incident management system (IMS) for efficient inter-sectoral coordination and collaboration for effective control of Dengue fever outbreak in Pakistan - 2019.

Public Health Emergency Operations Center (PH-EOC) and Incident Management System (IMS) provides a platform for inter-sectoral coordination, and collaboration to enhance efficiency of response activities and help in effective control of disease outbreaks. Dengue fever (DF) is an emerging serious public health threat with a potential to transform into a public health emergency. Pakistan faced a heavy outbreak of Dengue fever (DF) from August to December 2019.

Quantifying movement patterns and vaccination status of high risk mobile populations in Pakistan and Afghanistan to inform poliovirus risk and vaccination strategy.

Background: Stopping serotype 1 wild poliovirus transmission in Pakistan and Afghanistan requires ensuring all children <5 years of age are repeatedly vaccinated, including the large proportion living in mobile groups. Vaccinating children living in high-risk mobile populations (HRMPs) remains a priority for the polio programme.

Methods: In 2017-2018, group-level censuses were conducted in 43 districts of Pakistan, gathering information for all HRMP children <5 years of age residing in settlements.

Routine immunization coverage in Pakistan: a survey of children under 1 year of age in community-based vaccination areas.

Pakistan is one of two countries in which poliovirus remains endemic. Considering the high number of children born every year, reaching and vaccinating new birth cohorts by improving routine immunization coverage in children <1 year of age is crucial to halting virus transmission. In 2015, a community-based vaccination (CBV) strategy, using local community members to enhance vaccine acceptance and improve routine immunization service delivery, was introduced in areas of Pakistan that have never interrupted poliovirus transmission.

Needle-free injectors for mass administration of fractional dose inactivated poliovirus vaccine in Karachi, Pakistan: A survey of caregiver and vaccinator acceptability.

The first large-scale vaccination campaign using needle-free jet injectors to administer fractional doses of inactivated poliovirus vaccine (fIPV) was conducted in Karachi, Pakistan, in February 2019. Data on acceptability of jet injectors were collected from 610 vaccinators and 4898 caregivers during the first four days of the campaign. Of those with prior needle and syringe experience, both vaccinators and caregivers expressed a strong preference for jet injectors (578/592 [97.

Assessing the sensitivity of the polio environmental surveillance system.

Background: The polio environmental surveillance (ES) system has been an incredible tool for advancing polio eradication efforts because of its ability to highlight the spatial and temporal extent of poliovirus circulation. While ES often outperforms, or is more sensitive than AFP surveillance, the sensitivity of the ES system has not been well characterized. Fundamental uncertainty of ES site sensitivity makes it difficult to interpret results from ES, particularly negative results.

Effect of Inactivated Poliovirus Vaccine Campaigns, Pakistan, 2014-2017.

Pakistan began using inactivated poliovirus vaccine alongside oral vaccine in mass campaigns to accelerate eradication of wild-type poliovirus in 2014. Using case-based and environmental surveillance data for January 2014-October 2017, we found that these campaigns reduced wild-type poliovirus detection more than campaigns that used only oral vaccine.

Population sensitivity of acute flaccid paralysis and environmental surveillance for serotype 1 poliovirus in Pakistan: an observational study.

Background: To support poliomyelitis eradication in Pakistan, environmental surveillance (ES) of wastewater has been expanded alongside surveillance for acute flaccid paralysis (AFP). ES is a relatively new method of surveillance, and the population sensitivity of detecting poliovirus within endemic settings requires estimation.

Methods: Data for wild serotype 1 poliovirus from AFP and ES from January 2011 to September 2015 from 14 districts in Pakistan were analysed using a multi-state model framework.

Routine immunization in Pakistan: comparison of multiple data sources and identification of factors associated with vaccination.

Background: Within Pakistan, estimates of vaccination coverage with the pentavalent vaccine, oral polio vaccine (OPV) and measles vaccine (MV) in 2011 were reported to be 74%, 75% and 53%, respectively. These national estimates may mask regional variation. The reasons for this variation have not been explored.

Fractional-Dose Inactivated Poliovirus Vaccine Campaign - Sindh Province, Pakistan, 2016.

Following the declaration of eradication of wild poliovirus (WPV) type 2 in September 2015, trivalent oral poliovirus vaccine (tOPV) was withdrawn globally to reduce the risk for type 2 vaccine-derived poliovirus (VDPV2) transmission; all countries implemented a synchronized switch to bivalent OPV (type 1 and 3) in April 2016 (1,2). Any isolation of VDPV2 after the switch is to be treated as a potential public health emergency and might indicate the need for supplementary immunization activities (3,4). On August 9, 2016, VDPV2 was isolated from a sewage sample taken from an environmental surveillance site in Hyderabad, Sindh province, Pakistan.

Spatial model for risk prediction and sub-national prioritization to aid poliovirus eradication in Pakistan.

Background: Pakistan is one of only three countries where poliovirus circulation remains endemic. For the Pakistan Polio Eradication Program, identifying high risk districts is essential to target interventions and allocate limited resources.

Methods: Using a hierarchical Bayesian framework we developed a spatial Poisson hurdle model to jointly model the probability of one or more paralytic polio cases, and the number of cases that would be detected in the event of an outbreak.

Risk factors and short-term projections for serotype-1 poliomyelitis incidence in Pakistan: A spatiotemporal analysis.

Background: Pakistan currently provides a substantial challenge to global polio eradication, having contributed to 73% of reported poliomyelitis in 2015 and 54% in 2016. A better understanding of the risk factors and movement patterns that contribute to poliovirus transmission across Pakistan would support evidence-based planning for mass vaccination campaigns.

Methods And Findings: We fit mixed-effects logistic regression models to routine surveillance data recording the presence of poliomyelitis associated with wild-type 1 poliovirus in districts of Pakistan over 6-month intervals between 2010 to 2016.

Progress Toward Poliomyelitis Eradication - Pakistan, January 2015-September 2016.

Pakistan, Afghanistan, and Nigeria remain the only countries where endemic wild poliovirus type 1 (WPV1) transmission continues. This report describes the activities, challenges, and progress toward polio eradication in Pakistan during January 2015-September 2016 and updates previous reports (1,2). In 2015, a total of 54 WPV1 cases were reported in Pakistan, an 82% decrease from 2014.

Population Immunity against Serotype-2 Poliomyelitis Leading up to the Global Withdrawal of the Oral Poliovirus Vaccine: Spatio-temporal Modelling of Surveillance Data.

Background: Global withdrawal of serotype-2 oral poliovirus vaccine (OPV2) took place in April 2016. This marked a milestone in global polio eradication and was a public health intervention of unprecedented scale, affecting 155 countries. Achieving high levels of serotype-2 population immunity before OPV2 withdrawal was critical to avoid subsequent outbreaks of serotype-2 vaccine-derived polioviruses (VDPV2s).

Progress Toward Poliomyelitis Eradication--Pakistan, January 2014-September 2015.

Since Nigeria reported its last case of wild poliovirus type 1 (WPV1) in July 2014, Pakistan and Afghanistan remain the only two countries where WPV transmission has never been interrupted. This report describes actions taken and progress achieved toward polio eradication in Pakistan during January 2014-September 2015 and updates previous reports. A total of 38 WPV1 cases were reported in Pakistan during January-September 2015, compared with 243 during the same period in 2014 (an 84% decline).