Impact of COVID-19 on polio vaccination in Pakistan: a concise overview

Demographic and clinical features of dengue fever infection in Pakistan: a cross-sectional epidemiological study

BACKGROUND

Dengue fever caused by dengue virus is a tropical disease and is among the deadliest vector-borne diseases. The humid and hot summers of Pakistan support the probation of the vectors responsible for the transmission of viral and other parasitic diseases.

METHODOLOGY

A retrospective study, from 2012- 2019, of dengue infected individuals from the Punjab province of Pakistan was carried out to analyze epidemiology, clinical and laboratory findings of subjects with dengue virus infection. Data was derived from National Institute of Health (NIH) followed by Dengue control program of Pakistan, covering the incidence rate in 36 districts of Punjab and Islamabad Capital Territory (ICT) respectively. Patients data including the presence of dengue specific antigen or/and antibodies such as NS1 and IgG/IgM were observed. The study also included the analysis of demographic data, geographic data, and the month-wise distribution of dengue cases to examine seasonal trends.

RESULTS

We analyzed 25,682 dengue infected individuals. The statistical analysis revealed a significant association between genders in which male population was more affected by dengue than females. It was also noted that the middle age group was the most affected age group while the highest number of cases were reported in October. Rawalpindi and Lahore were the most affected cities in Punjab province while Islamabad represented the highest number of cases during the recent outbreak in 2019. The IgM and IgG antibodies were highly prevalent among the infected patients.

CONCLUSION

Dengue is endemic in Pakistan, circulating throughout the year. Highest number of cases were observed in the month of October, September and November respectively. Association between climate change and vector-borne diseases need to be investigated in Pakistan as they significantly influence the timing and intensity of dengue and other disease outbreaks. Further exploration of hematological parameters is required to better diagnose and treat the disease. For the effective control of dengue outbreaks, awareness campaigns on sewage management and vector control along with social factors are strongly recommended for better control and eradication of the disease.

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. 25 clusters from each geographical stratum were selected utilizing probability proportional to size.

Results

Seroprevalence of type 2 poliovirus was 49%, with significant variation observed among surveyed areas; <30% in Pishin, >80% in Killa Abdullah, Mardan & Swabi, and Rawalpindi. SIAs with IPV improved immunity from 38 to 57% in Karachi and 60 to 88% in Khyber. SIAs with IPV following mOPV2 improved immunity from 62 to 65% in Killa Abdullah, and combined mOPV2 and IPV SIAs in Pishin improved immunity from 28 to 89%. Results also reflected that immunity rates for serotypes 1 and 3 were consistently above 90% during all three phases and across all geographical areas.

Conclusion

The study findings highlight the importance of implementing effective vaccination strategies to prevent the re-emergence of poliovirus. Moreover, the results provide crucial information for policymakers working toward achieving global polio eradication.

MA, Tovar-Rosero YY, Oñate AA, O'Ryan M. Two centuries of vaccination: historical and conceptual approach and future perspectives

Over the past two centuries, vaccines have been critical for the prevention of infectious diseases and are considered milestones in the medical and public health history. The World Health Organization estimates that vaccination currently prevents approximately 3.5-5 million deaths annually, attributed to diseases such as diphtheria, tetanus, pertussis, influenza, and measles. Vaccination has been instrumental in eradicating important pathogens, including the smallpox virus and wild poliovirus types 2 and 3. This narrative review offers a detailed journey through the history and advancements in vaccinology, tailored for healthcare workers. It traces pivotal milestones, beginning with the variolation practices in the early 17th century, the development of the first smallpox vaccine, and the continuous evolution and innovation in vaccine development up to the present day. We also briefly review immunological principles underlying vaccination, as well as the main vaccine types, with a special mention of the recently introduced mRNA vaccine technology. Additionally, we discuss the broad benefits of vaccines, including their role in reducing morbidity and mortality, and in fostering socioeconomic development in communities. Finally, we address the issue of vaccine hesitancy and discuss effective strategies to promote vaccine acceptance. Research, collaboration, and the widespread acceptance and use of vaccines are imperative for the continued success of vaccination programs in controlling and ultimately eradicating infectious diseases.

Routine immunization experience and practices during the COVID-19 pandemic of caregivers attending a tertiary hospital in Cape Town

Introduction

Immunizations are successful, cost-effective interventions for the control of infectious diseases and preventing mortality. Lockdown restrictions during the COVID-19 pandemic had adverse effects on child-health including access to immunizations. Our study aimed to document immunization status, describe caregiver experiences around accessing immunizations during the COVID-19 pandemic and identify any significant factors associated with immunization status.

Methods

Caregivers, with children between the ages of 10 to 33 months, attending Tygerberg Hospital Paediatric Department were invited to complete an anonymous survey from 15th September-15th December 2022. Data was captured using a REDCap questionnaire and analysed using Stata Version 17.

Results

171 caregivers completed the survey. Immunizations were up to date in 81%. Most (155, 88%) agreed it was important to immunize their child. A third of caregivers (55) felt it was unsafe to attend the clinic and 37% (62) agreed it was difficult to attend. Caregivers receiving a social grant (p = 0.023) or who felt safe attending clinic (p = 0.053) were more likely to be up to date with immunizations. Three-quarters (128, 78%) were aware of recommendations to continue immunization. These caregivers were more likely to think it was important to immunize on time (p = 0.003) and to receive family encouragement (p = 0.001). Caregivers were more likely to attend clinic if they felt it was important to vaccinate on time (p < 0.001) or felt safe attending clinic (p = 0.036).

Conclusion

Immunization rates were higher than expected but below global targets. Although caregivers feel immunizations are important, unknowns still instilled fear of attending clinics. Social factors such as family support and social grants improve vaccine seeking behaviour.

Lifting non-pharmaceutical interventions following the COVID-19 pandemic - the quiet before the storm?

INTRODUCTION

In the first months of the novel coronavirus (COVID-19) pandemic that begun in 2020, non-pharmaceutical interventions (NPIs) have been adopted worldwide. However, the effects of NPI implementation go beyond slowing the spread of COVID-19. Here, we review the non-intended effects that may have arisen from prolonged application of NPIs.

AREAS COVERED

NPIs also affected the epidemiology of other infectious diseases, with unprecedentedly low circulation of several respiratory and gastrointestinal viruses being observed worldwide in 2020. While this was a welcome effect for already strained healthcare systems, prolonged low exposure to pathogens may result in an increased pool of individuals susceptible to certain diseases. Out-of-season or unusually intense outbreaks of non-vaccine preventable diseases have already been documented as NPIs were gradually eased. In the context of widespread and important disruptions in national vaccination programs during the early phase of the pandemic, the risk of vaccine-preventable disease resurgence after NPIs are lifted cannot be excluded either.

EXPERT OPINION

Awareness must be raised of the risk of vaccine-preventable disease resurgence, and efforts need to be made to mitigate this risk, where possible, by increasing vaccination coverage. Research and regulatory opportunities brought on by the COVID-19 pandemic should be seized.

Polio amidst COVID-19 in Pakistan: Ongoing efforts, challenges, and recommendations

Poliomyelitis is a crippling viral disease caused by poliovirus, a positive‐stranded RNA virus that is a serotype of Enterovirus C. Pakistan remains one of the countries in the world where poliomyelitis is still prevalent, posing an obstacle to global poliomyelitis eradication. With the commencement of the COVID‐19 pandemic, polio eradication campaigns have proven less feasible, resulting in an increase in polio cases across the country. Pakistan's healthcare system and socio‐economic framework are incapable of dealing with two deadly viruses at the same time. As a result, effective measures for combating the destruction caused by the spread of the poliovirus are required.

Pakistan remains one of the nations in the world where poliomyelitis is still prevalent.

The number of polio cases in Pakistan has increased due to the disruption in vaccination procedures caused by the COVID‐19‐induced lockdown.

Aside from Polio, the COVID‐19 pandemic has resulted in an increase in the number of other infectious diseases.

The country still has the potential to eradicate polio from its soil if effective tactics, mass awareness, and public compliance are implemented.

Multidrug-Resistant Infections in the Developing World

Antimicrobials are essential in reducing morbidity and mortality from infectious diseases globally. However, due to the lack of effective surveillance measures and widespread overuse, there is an increasing threat to the effectiveness of antimicrobials. Although there is a global increase in antimicrobial resistance, low- and middle-income countries share a much higher burden. Antimicrobial stewardship efforts such as effective surveillance and reduction in overuse can help combat the increase in antimicrobial resistance.

COVID-19 Impact on Disparity in Childhood Immunization in Low- and Middle-Income Countries Through the Lens of Historical Pandemics

Purpose of Review

The COVID-19 pandemic, since 2020, has affected health care services and access globally. Although the entire impact of COVID-19 pandemic on existing global public health is yet to be fully seen, the impact of COVID-19 pandemic on global childhood immunization programs is of particular importance.

Recent Findings

Disruptions to service delivery due to lockdowns, challenges in vaccination programs, vaccine misinformation and hesitancy, and political and social economic inequalities all posed a threat to existing childhood immunization programs. These potential threats were especially critical in LMIC where childhood immunization programs tend to experience suboptimal implementation.

Summary

This review provides an overview of childhood immunizations and discusses past pandemics particularly in LMIC, factors contributing to disparities in childhood immunizations, and reviews potential lessons to be learned from past pandemics. Vaccine hesitancy, social determinants of health, and best practices to help lessen the pandemic's influence are also further elaborated. To address current challenges that hindered the progress made in prevention of childhood illnesses through vaccination campaigns and increased vaccine availability, lessons learned through best practices explored from past pandemics must be examined to mitigate impact of COVID-19 on childhood immunization and in turn conserve health and improve economic well-being of children especially in LMIC.

Assessing the impact of polio supplementary immunisation activities on routine immunisation and health systems: a systematic review

Introduction

The Global Polio Eradication Initiative uses polio supplementary immunisation activities (SIAs) as a strategy to increase vaccine coverage and cease poliovirus transmission. Impact of polio SIAs on immunisation systems is frequently debated. We reviewed the impact of polio SIAs on routine immunisation and health systems during the modern era of polio eradication.

Methods

We searched nine databases for studies reporting on polio SIAs and immunisation coverage, financial investment, workforce and health services delivery. We conducted a narrative synthesis of evidence. Records prior to 1994, animal, modelling or case studies data were excluded.

Results

20/1637 unique records were included. Data on vaccine coverage were included in 70% (14/20) studies, workforce in 65% (13/20) and health services delivery in 85% (17/20). SIAs positively contributed to vaccination uptake of non-polio vaccines in seven studies, neutral in three and negative in one. Some polio SIAs contributed to workforce strengthening through training and capacity building. Polio SIAs were accompanied with increased social mobilisation and community awareness building confidence in vaccination programmes. Included studies were programmatic in nature and contained variable data, thus could not be justly critically appraised.

Conclusion

Polio SIAs are successful at increasing polio vaccine coverage, but the resources and infrastructures were not always utilised for delivery of non-polio vaccines and integration into routine service delivery. We found a gap in standardised tools to evaluate SIAs, which can then inform service integration. Our study provides data to inform SIAs evaluations, and provides important considerations for COVID-19 vaccine roll-out to strengthen health systems.

PROSPERO registration number

CRD42020152195.

A novel semi-quantitative methodology for national poliovirus reintroduction and outbreak risk assessment

BACKGROUND

Under the International Health Regulations (2005), World Health Organization Member States need to verify certification of polio-free status annually. In 2018, Australia sought to reassess and comprehensively characterise the risk posed by wild-type and vaccine-derived poliovirus introductions to national health security. However formal guidelines for national polio risk assessment were not publicly available.

METHODS

Four risk elements were identified and weighted using an expert-informed modified Delphi method: reintroduction hazard; population susceptibility; detection capability; and response capability. Australian data and qualitative evidence were analysed, documented and scored against risk element indicators to characterise polio risk as a semi-quantitative estimate and qualitative risk category statement.

RESULTS

The semi-quantitative risk characterisation calculated likelihood and impact scores of 0.43 and 0.13, respectively (possible range: 0.02-4.5). The assessment concluded that the risk of poliovirus reintroduction, resultant outbreaks of poliovirus infection, and sustained transmission occurring in Australia is very low.

CONCLUSIONS

Until poliovirus is eradicated, it remains in countries' strategic health security interest to maintain optimal investment in polio prevention, preparedness, surveillance and response capability to manage their level of risk. We present a structured, transparent and reproducible methodology for national or sub-national polio risk characterisation that generates evidence for targeted investment to maintain polio-free status.

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. The model includes geographic heterogeneities in vaccination coverage, population immunity and population movement. The model was fitted to historic cVDPV2 cases in Pakistan and Afghanistan between January 2010-April 2016 and July 2019-March 2020 using iterated particle filtering. The model was used to simulate spread of cVDPV2 infection from July 2019 to explore impact of various proposed vaccination responses on stopping transmission and risk of spread of reverted Sabin-2 under varying assumptions of impacts from COVID-19 lockdown measures on movement patterns as well as declines in vaccination coverage.

Results

Simulated monthly incidence of cVDPV2 from the best-fit model demonstrated general spatio-temporal alignment with observed cVDPV2 cases. The model predicted substantial spread of cVDPV2 infection, with widespread transmission through 2020 in the absence of any vaccination activities. Vaccination responses were predicted to substantially reduce transmission and case burden, with a greater impact from earlier responses and those with larger geographic scope. While the greatest risk of seeding reverted Sabin-2 was predicted in areas targeted with OPV2, subsequent spread was greatest in areas with no or delayed response. The proposed vaccination strategy demonstrated ability to stop the cVDPV2 outbreak (with low risk of reverted Sabin-2 spread) by February 2021.

Conclusion

Outbreak response vaccination campaigns against cVDPV2 will be challenging throughout the COVID-19 pandemic but must be implemented urgently when feasible to stop transmission of cVDPV2.

Evaluation of serum procalcitonin level as a biomarker for disease severity in COVID-19 patients

The pandemic of coronavirus disease 2019 (COVID-19) has infected millions of individuals around the globe. Forecasting the COVID-19 severity is essential, and various biomarkers could be used to evaluate it. The current study was therefore aimed to evaluate the serum pro-calcitonin (PCT) level as a biomarker for bacterial co-infection and disease severity in COVID-19 patients. A total of 430 COVID-19 positive individuals were examined, in which 332 (77.2%) were male individuals while 98 (22.8%) were female individuals. Among the examined samples, 281 were classified as moderate (PCT value 0.07 ± 0.06 ng/mL), 95 were severe (PCT value 0.5 ± 0.4 ng/mL), and 54 were classified as critical (PCT value > 1 ng/mL) individuals. The increase in the total serum level of PCT was observed with the severity of the disease (p < 0.05). The statistical analysis represented no association of PCT value with gender (p 0.9650) while revealed a significant association (p < 0.001) with the age and PCT value in COVID-19 patients. It can be concluded that the serial PCT measurement could determine the prognosis of the disease and the presence of bacterial co-infection in COVID-19 patients. Further exploration of the topic is needed to evaluate the effect of different therapies on the PCT level and to prescribe specific treatment options for coinfection.

The Global Interest in Vaccines and Its Prediction and Perspectives in the Era of COVID-19. Real-Time Surveillance Using Google Trends

Background: The COVID-19 pandemic has globally overwhelmed all sectors of life. The fast development of vaccines against COVID-19 has had a significant impact on the course of the pandemic. Methods: Global data from Google Trends was analyzed for vaccines against flu, BCG, HPV, pneumococcal disease, polio, and COVID-19. The time frame includes the last five-year period starting from 17 April 2016. Multiple training of time series models with back testing, including Holt–Winters forecasting, Exponential Smoothing State Space, Linear model with trend and seasonal components (tlsm), and ARIMA was conducted. Forecasting according to the best fitting model was performed. Results: Correlation analysis did not reveal a decrease in interest in vaccines during the analyzed period. The prediction models provided a short-term forecast of the dynamics of interest for flu, HPV, pneumococcal and polio vaccines with 5–10% growth in interest for the first quarter of 2022 when compared to the same quarter of 2021. Conclusions: Despite the huge interest in the COVID-19 vaccine, there has not been a detectable decline in the overall interest in the five analyzed vaccines.

Evaluation of hematological parameters as an indicator of disease severity in Covid-19 patients: Pakistan's experience

BACKGROUND

The severity of COVID-19 could be evaluated by examining several blood parameters mainly white blood cell (WBC) count, granulocytes, platelet, and novel hemocytometric markers neutrophils to lymphocyte ratio (NLR), platelet-to-lymphocyte (PLR), and lymphocyte to monocyte ratio (LMR). The current study was conducted to investigate alteration in blood parameters and their association with the severity and mortality of COVID-19 patients.

METHODOLOGY

An observational cross-sectional study was conducted retrospectively, a total of 101 COVID-19 positive patients were examined: 52 were mild, 24 were moderate, 09 were severe, and 16 were critically diseased patients. We also recorded 16 deaths associated with the critical group. The overall mean age observed in our study was 48.94 years, where the mean age for critical individuals was 62.12 ± 14.35 years.

RESULTS

A significant association between the disease severity and elevation in blood parameters were observed. The WBC's and granulocyte count were significantly increased (p value <0.001) while the mean platelet count (165.0 × 109 /L) and red blood cell volume distribution width (RDW) were decreased in the critical group (57.86%) compared to mild group's patients (177.3%) (p = 0.83). The lymphocytes count was decreased in critical patients (1.40 × 109 /L) compared to mild patients (1.92 × 109 /L) (p = 0.28). A significant association was observed in platelet-lymphocyte ratio (p < 0.001), Neutrophil-Lymphocyte ratio (p = <0.001), and Lymphocyte-Monocyte ratio (0.011).

CONCLUSION

These blood parameters could be used as a suitable biomarker for the prognosis and severity of COVID-19. Evaluating novel hemograms NLR, PLR, and LMR can aid clinicians to identify potentially severe cases at early stages, initiate effective management in time, and conduct early triage which may reduce the overall mortality of COVID-19 patients.

A short review on key role of plants and their extracts in boosting up immune response to combat COVID-19

In the wake of the recent global pandemic of COVID-19, there has been an increasing concern among the general public to improve their immune system. The causative agent of COVID-19 is SARS CoV-2, similar to its relative viruses SARS Cov-1 and MERS. Up till now, no vaccine has been developed against this disease and the only way one can stay safe is via prevention and developing one's immune system. Plants have been used since ancient times in herbal medicines and many chemicals and extracts in them are found to boost the immune system. Therefore, a consciously maintained diet consisting of plant-based immunity boosters is the need of the hour. Plants are known to provide many chemicals, natural therapeutics and vitamins which naturally enhance our immune system. Recently, vaccination research is also being carried out in transgenic plants. In this review, we have focused on highlighting some of the main players within the Kingdom Plantae which, when taken up in regular diet, can significantly boost our immune system capacity and thus provide the best possible measure to combat this pandemic.

Eradicating polio in Pakistan: a systematic review of programs and policies

Introduction: Established in 1994, Pakistan's polio program demonstrated early success. However, despite over 120 supplementary immunization activities in the last decade, polio eradication efforts in Pakistan have been unable to achieve their objective of halting polio transmission. Variable governance, and inconsistent leadership and accountability have hindered the success of the polio program and the quality of the campaigns. Insecurity and terrorism has interrupted polio activities, and community fears and misbeliefs about polio vaccinations continue to persist.Areas covered: The article consists of a systematic review of the barriers and facilitators associated with the delivery of polio eradication activities in Pakistan. We also provide a comprehensive review of the policy and programmatic decisions made by the Pakistan Polio Programme since 1994. Searches were conducted on Embase and Medline databases and 25 gray literature sources.Expert opinion: Polio eradication efforts must be integrated with other preventive health services, particularly immunization services. Addressing the underlying causes of polio refusals including underdevelopment and social exclusion will help counteract resistance to polio vaccination. Achieving polio eradication will require building health systems that provide comprehensive community-centered care, and improving governance and systems of accountability.