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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 [...]

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]

Of the 3 wild poliovirus (WPV) serotypes, only type 1 (WPV1) has been detected globally since 2012. Pakistan remains 1 of only 3 countries worldwide (in addition to Afghanistan and [...]

In 1988, the World Health Assembly launched the Global Polio Eradication Initiative. Of the 3 wild poliovirus serotypes, only wild poliovirus type 1 (WPV1) has been detected since 2012. Since [...]

Background: Elimination of poliovirus in Pakistan and Afghanistan is challenged by notions against the role of oral poliovirus vaccine (OPV) in eradicating contemporary wild poliovirus (WPV) strains.Methods: A total of 1055 WPV type 1 (WPV1) strains isolated between 2013 and 2018 were categorized into 68 antigenic groups and tested for neutralization by OPV-derived antibodies. Molecular docking was conducted to determine neutralization efficiency of antibodies against WPV. The clinical significance of WPV1 variants was assessed to ascertain their role in patient outcomes.Results: We found that 88% of WPV1 strains isolated from paralytic children belonged to a single antigenic lineage identical to the WPV1 strain detected in 1993. WPV1 antigenic variants were effectively neutralized by OPV-derived antibodies, with geometric mean titers comparable to the neutralization titers found for 3 strains in OPV (OPV1-3, 7.96-9.149 [95% confidence interval, 6.864-10.171]; WPV1 strains, 7.542-8.786 [6.493-9.869]). Docking examination underscored a strong antigen-antibody interaction despite variations within the viral protein 1 epitopes. There was no significant association (P = .78) with clinical prognosis among patients infected with antigenically diverse WPV1 strains and patient outcomes, including death.Conclusions: Our findings substantiate the robustness of OPV for neutralizing the contemporary WPV1 strains endemic in Pakistan and Afghanistan. Vaccination coverage must be augmented to achieve early eradication. [ABSTRACT FROM AUTHOR]

Using a simple metagenornic approach, we identified a divergent human pareehovirus (HPeV) in the stool of a child in Pakistan. Genomic characterization showed this virus was distinct enough from reported [...]

To the Editor: Crimean-Congo hemorrhagic fever (CCHF) is a tickborne zoonotic disease caused by a member of the virus family Bunyaviridae, genus Nairovirus. This virus (CCHFV) has caused illness throughout [...]

Abstract Background/Aim Efforts have been made to eliminate wild poliovirus transmission since 1988 when the World Health Organization began its global eradication campaign. Since then, the incidence of polio has decreased significantly. However, serotype 1 and serotype 3 still circulate endemically in Pakistan and Afghanistan. Both countries constitute a single epidemiologic block representing one of the three remaining major global reservoirs of poliovirus transmission. In this study we used genetic sequence data to investigate transmission links among viruses from diverse locations during 2005-2007. Methods In order to find the origins and routes of wild type 1 poliovirus circulation, polioviruses were isolated from faecal samples of Acute Flaccid Paralysis (AFP) patients. We used viral cultures, two intratypic differentiation methods PCR, ELISA to characterize as vaccine or wild type 1 and nucleic acid sequencing of entire VP1 region of poliovirus genome to determine the genetic relatedness. Results One hundred eleven wild type 1 poliovirus isolates were subjected to nucleotide sequencing for genetic variation study. Considering the 15% divergence of the sequences from Sabin 1, Phylogenetic analysis by MEGA software revealed that active inter and intra country transmission of many genetically distinct strains of wild poliovirus type 1 belonged to genotype SOAS which is indigenous in this region. By grouping wild type 1 polioviruses according to nucleotide sequence homology, three distinct clusters A, B and C were obtained with multiple chains of transmission together with some silent circulations represented by orphan lineages. Conclusion Our results emphasize that there was a persistent transmission of wild type1 polioviruses in Pakistan and Afghanistan during 2005-2007. The epidemiologic information provided by the sequence data can contribute to the formulation of better strategies for poliomyelitis control to those critical areas, associated with high risk population groups which include migrants, internally displaced people, and refugees. The implication of this study is to maintain high quality mass immunization with oral polio vaccine (OPV) in order to interrupt chains of virus transmission in both countries to endorse substantial progress in Eastern-Mediterranean region.

Abstract Background Eight genotypes of Hepatitis B virus designated A-H, have been known but in Pakistan, no such data is available on the prevalent HBV genotypes. Therefore, the subject study was conducted to determine HBV genotypes in the indigenous Pakistani population. Methods A total of 690 individuals were enrolled for HBV screening with EIA and nested PCR. Positive samples were further analyzed to determine HBV genotypes (A-F) by multiplex-PCR using type specific primers. Results 110 (15.94%) individuals were positive for HBV, including 64% males and 36% females. Out of these, 66 samples (65.34%) were classified into genotype D, 27 (26.73%) were of genotype B while 5(4.95%) had genotype A. In 3 (2.98%) samples, multiple genotypes were detected (genotype A+B; 2(1.99%) and genotypes B+D; 1(0.99%). Nine (8.18%) samples remained untyable. Conclusion In Asia, genotypes B and C are the most prevalent but our study reveals that genotype D is predominant and HBV infection constitutes a significant health problem in Pakistan.

Abstract Background The epidemiological significance of Hepatitis B virus genotypes has been well established and becoming an essential concern day by day however, much little is known about the mixed infection with more than one Hepatitis B virus genotypes and their clinical relevance. Methods Intravenous drug abusers are considered as a major risk group for the acquisition and transmission of blood borne infections like hepatitis B, however, in Pakistan, no such data has ever been reported about the epidemiology of HBV and its genotypes in Injecting Drug Users. 250 individuals were analyzed for hepatitis B virus genotypes after prior screening with serological assay for the detection of HBsAg. Results 56 (22.4%) individuals were found positive on ELSIA for HBsAg. The genotype distribution was found to be as: genotype D, 62.5%; genotype A, 8.92% while 28.57% individuals were found to be infected with a mixture of genotype A and D. Conclusion There is an urgent need of the time to develop public health care policies with special emphasis towards the control of HBV transmission through high risk groups especially Injecting Drug Users.

Abstract Background The infection rate of hepatitis B virus is continuously increasing in Pakistan. Therefore, a comprehensive study of epidemiological data is the need of time. Methods A total of 1300 individuals were screened for HBV infection markers including HBsAg, anti-HBsAg, HBeAg and anti-HBcAg. The association of these disease indicators was compared with patients' epidemiological characteristics like age, socio-economic status and residential area to analyze and find out the possible correlation among these variables and the patients disease status. Results 52 (4%) individuals were found positive for HBsAg with mean age 23.5 ± 3.7 years. 9.30%, 33.47% and 12% individuals had HBeAg, antibodies for HBsAg, and antibodies for HBcAg respectively. HBsAg seropositivity rate was significantly associated (p = 0.03) with the residing locality indicating high infection in rural areas. Antibodies titer against HBsAg decreased with the increasing age reflecting an inverse correlation. Conclusion Our results indicate high prevalence rate of Hepatitis B virus infection and nationwide vaccination campaigns along with public awareness and educational programs are needed to be practiced urgently.

Abstract Background Enteroviruses are among the most common viruses infecting humans worldwide and they are associated with diverse clinical syndromes. Acute flaccid paralysis (AFP) is a clinical manifestation of enteroviral neuropathy, transverse myelitis, Guillian-Barre Syndrome, Traumatic neuritis and many other nervous system disorders. The objective of this study was to understand the role of Non-Polio Enteroviruses (NPEV) towards this crippling disorder. Methods Stool specimens of 1775 children, aged less than 15 years, suffering from acute flaccid paralysis were collected after informed consent within 14 days of onset of symptoms during January 2003 to September 2003. The specimens were inoculated on RD and L20B cells using conventional tube cell culture while micro-neutralization test was used to identify the non-polio enterovirus (NPEV) serotypes. Detailed clinical information and 60-days follow-up reports were analyzed for NPEV-associated AFP cases. Results NPEV were isolated from 474 samples. The male to female ratio was 1.4:1. The isolation of NPEV decreased significantly with the increase in age. Cases associated with fever at the onset of NPEV-associated AFP were found to be 62%. The paralysis was found asymmetrical in 67% cases, the progression of paralysis to peak within 4 days was found in 72% cases and residual paralysis after 60 days of paralysis onset was observed in 39% cases associated with NPEV. A clinical diagnosis of Guillian-Barre syndrome was made in 32% cases. On Microneutralization assay, echo-6 (13%) and coxsackievirus B (13%) were the most commonly isolated serotypes of NPEV along with E-7, E-13, E-11, E-4 and E-30. The isolates (n = 181) found untypable by the antiserum pools were confirmed as NPEV by PCR using Pan-Enterovirus primers. Conclusion The present study suggests that NPEV are a dominant cause of AFP and different serotypes of NPEV are randomly distributed in Pakistan. The untypable isolates need further characterization and analysis in order to determine their association with clinical presentation of a case.

Background Pakistan is among 3 countries endemic for wild poliovirus type 1 (WPV1) circulation that are still struggling for eradication of poliomyelitis. Active clinical and environmental surveillance with meticulous laboratory investigations provide insights into poliovirus transmission patterns and genomic diversity to inform decisions for strategic operations required to achieve eradication. Methods We analyzed epidemiological and virological data to comprehend the current epidemiological status of WPV1 in Pakistan during 2015–2017. Stool specimens of patients with acute flaccid paralysis (AFP) and sewage samples collected from 60 environmental sites were tested. Viral culturing, intratypic differentiation by real-time polymerase chain reaction, and nucleic acid sequencing of the VP1 region of the poliovirus genome to determine genetic relatedness among WPV1 strains were applied. Results Poliovirus isolates were grouped into 11 distinct clusters, which had ≥95% nucleotide homology in the VP1 coding region. Most of the poliovirus burden was shared by 3 major reservoirs: Karachi, Peshawar, and Quetta block (64.2% in 2015, 75.4% in 2016, and 76.7% in 2017). Conclusions Environmental surveillance reveals importations and pockets of unimmunized children that dictate intensive target mop-up campaigns to contain poliovirus transmission. A decrease in the number of orphan isolates reflects effective combination of AFP and environmental surveillance in Pakistan. The genetic data reflect sustained transmission within reservoir areas, further expanded by periodic importations to areas of high immunity reflected by immediate termination of imported viruses. Improved immunization coverage with high-quality surveillance is vital for global certification of polio eradication. [ABSTRACT FROM AUTHOR]