NTDs in the age of urbanization, climate change, and conflict: Karachi, Pakistan as a case study

Vaccines in a time of global boiling and megacities

Neglected tropical diseases are accelerating because of climate change and urbanization to create new clusters of vast urban areas beset by poverty and environmental degradation. These hot and contaminated megacities could enable the rise of parasitic and other tropical infections. A new generation of antiparasitic vaccines will be needed.

Insights to Design New Drugs against Human African Trypanosomiasis Targeting Rhodesain using Covalent Docking, Molecular Dynamics Simulations, and MM-PBSA Calculations

BACKGROUND

Neglected tropical diseases (NTDs) are parasitic and bacterial diseases that affect approximately 149 countries, mainly the poor population without basic sanitation. Among these, Human African Trypanosomiasis (HAT), known as sleeping sickness, shows alarming data, with treatment based on suramin and pentamidine in the initial phase and melarsoprol and eflornithine in the chronic phase. Thus, to discover new drugs, several studies point to rhodesain as a promising drug target due to the function of protein degradation and intracellular transport of proteins between the insect and host cells and is present in all cycle phases of the parasite.

METHODS

Here, based on the previous studies by Nascimento et al. (2021) [5], that show the main rhodesain inhibitors development in the last decade, molecular docking and dynamics were applied in these inhibitors datasets to reveal crucial information that can be into drug design.

RESULTS

Also, our findings using MD simulations and MM-PBSA calculations confirmed Gly19, Gly23, Gly65, Asp161, and Trp184, showing high binding energy (ΔGbind between -72.782 to -124.477 kJ.mol-1). In addition, Van der Waals interactions have a better contribution (-140,930 to -96,988 kJ.mol-1) than electrostatic forces (-43,270 to -6,854 kJ.mol-1), indicating Van der Waals interactions are the leading forces in forming and maintaining ligand-rhodesain complexes. Thus, conventional and covalent docking was employed and highlighted the presence of Michael acceptors in the ligands in a peptidomimetics scaffold, and interaction with Gly19, Gly23, Gly65, Asp161, and Trp184 is essential to the inhibiting activity. Furthermore, the Dynamic Cross-Correlation Maps (DCCM) show more correlated movements for all complexes than the free rhodesain and strong interactions in the regions of the aforementioned residues. Principal Component Analysis (PCA) demonstrates complex stability corroborating with RMSF and RMSD.

CONCLUSION

This study can provide valuable insights that can guide researchers worldwide to discover a new promising drug against HAT.

"Dengue fever is not just urban or rural: Reframing its spatial categorization."

Infectious diseases exploit niches that are often spatially defined as urban and/or rural. Yet spatial research on infectious diseases often fails to define "urban" and "rural" and how these contexts might influence their epidemiology. We use dengue fever, thought to be mostly an urban disease with rural foci, as a device to explore local definitions of urban and rural spaces and the impact of these spaces on dengue risk in the province of Esmeraldas, Ecuador. Ecuador, like many countries, only uses population size and administrative function to define urban and rural locales. Interviews conducted from 2019 to 2021 with 71 residents and 23 health personnel found that they identified the availability of basic services, extent of their control over their environment, and presence of underbrush and weeds (known in Ecuador as monte and maleza and conceptualized in this paper as natural disorder) as important links to their conceptions of space and dengue risk. This broader conceptualization of space articulated by local residents and professionals reflects a more sophisticated approach to characterizing dengue risk than using categories of urban and rural employed by the national census and government. Rather than this dichotomous category of space, dengue fever can be better framed for health interventions in terms of specific environmental features and assemblages of high-risk spaces. An understanding of how community members perceive risk enhances our ability to collaborate with them to develop optimal mitigation strategies.

Cross-cultural adaptation and validation of an Urdu version of the Vaccine Attitudes Examination (VAX-U) scale

BACKGROUND

Martin and Petrie developed the Vaccine Attitudes Examination (VAX) scale with an aim to document general vaccination attitudes. Vaccine acceptance plays an important role in curbing COVID-19 infections. Thus, it was important to assess vaccination attitudes of Pakistani people towards novel COVID-19 vaccines. The VAX scale was not available in Urdu language for Pakistani population.

AIM

The study aimed to carry out cross-cultural adaptation and validation of an Urdu version of the Vaccine Attitude Examination (VAX) scale in a selected population sample from Pakistan.

METHODS

A cross sectional study was conducted in September 2021 in an outpatient department of a healthcare facility in Karachi, Pakistan. Adult visitors, eligible for COVID-19 vaccine and spoke Urdu as first language were invited. Convenient sampling was used, and sample size was based on an item response ratio of 1:20. An Urdu version of the VAX scale was developed. The reliability was assessed using Cronbach's alpha (α) and intraclass correlation coefficient (ICC). The model fitness was evaluated using confirmatory factor analysis (CFA) and fit indices namely goodness of fit index (GFI), adjusted goodness of fit index (AGFI), Tucker Lewis index (TLI), comparative fit index (CFI), and root mean square error of approximation (RMSEA). A structural equation model (SEM) was also developed. IBM SPSS and AMOS were used to analyse the data. The study had ethical clearance.

RESULTS

A total of 211 responses were analysed. The reliability (Cronbach's α) was 0.821. The ICC was 0.831 (95% CI: 0.795-0.863). CFA using a 4-factor model revealed the following values for fit indices; GFI = 0.944, AGFI = 0.909, TLI = 0.953, CFI = 0.966, and RMSEA = 0.051. All values reported were in the acceptable range.

CONCLUSION

The VAX Urdu version is a reliable and valid instrument for use in an Urdu speaking population and will enable clinicians to assess the public's attitude towards general vaccination including COVID-19 vaccination. Clinicians can use the VAX-U to document a person's vaccine hesitancy and tailor their counselling to address the issues in vaccine uptake.

Risk of infection with arboviruses in a healthy population in Pakistan based on seroprevalence

Infectious diseases caused by arboviruses are a public health concern in Pakistan. However, studies on data prevalence and threats posed by arboviruses are limited. This study investigated the seroprevalence of arboviruses in a healthy population in Pakistan, including severe fever with thrombocytopenia syndrome virus (SFTSV), Crimean-Congo hemorrhagic fever virus (CCHFV), Tamdy virus (TAMV), and Karshi virus (KSIV) based on a newly established luciferase immunoprecipitation system (LIPS) assays, and Zika virus (ZIKV) by enzyme-linked immunosorbent assays (ELISA). Neutralizing activities against these arboviruses were further examined from the antibody positive samples. The results showed that the seroprevalence of SFTSV, CCHFV, TAMV, KSIV, and ZIKV was 17.37%, 7.58%, 4.41%, 1.10%, and 6.48%, respectively, and neutralizing to SFTSV (1.79%), CCHFV (2.62%), and ZIKV (0.69%) were identified, as well as to the SFTSV-related Guertu virus (GTV, 0.83%). Risk factors associated with the incidence of exposure and levels of antibody response were analyzed. Moreover, co-exposure to different arboviruses was demonstrated, as thirty-seven individuals were having antibodies against multiple viruses and thirteen showed neutralizing activity. Males, individuals aged ≤40 years, and outdoor workers had a high risk of exposure to arboviruses. All these results reveal the substantial risks of infection with arboviruses in Pakistan, and indicate the threat from co-exposure to multiple arboviruses. The findings raise the need for further epidemiologic investigation in expanded regions and populations and the necessity to improve health surveillance in Pakistan.

Geospatial quality assessment of locally available ice for heavy metals and metalloids and their potential risks for human health in Karachi, Pakistan

Extreme hot conditions during summers, high poverty rate and continuous electricity load shedding affect commercial manufacturing and sale of ice in many countries. The vendors prepared ice using untreated piped water, tanker water and ground water. These waters may contain hazardous pollutants and ice made from them will pose a potential human health risk. Thus, it is important to regularly monitor the chemical composition of water sources and the quality of the manufactured ice. A contemporary examination was carried out to evaluate the physico-chemical properties and heavy metals and metalloids in the ice sold in all the districts of Karachi, Pakistan. This pioneering study was an innovative effort to assess the ice quality in relation to potential pollutant hazards to human health; with concomitant geospatial information. The geospatial distribution of ice quality and major constituents were among the measured parameters; carefully associated with further geospatial information, determined using GIS (Geographic Information Systems) and PCA (Principal Component Analysis) techniques. Interestingly, the physico-chemical analyses revealed that the ice quality was marginally adequate and the total mean metal-metalloid contents were in the sequence of Pb > Ni > Zn > Fe > Cr > As. The concentrations of these metals were above the upper allowable limits with reference to the recommended WHO guidelines. We observed that 57.1% and 35.7% ice samples had good physico-chemical properties assessed using the Ice Quality Index (IQI). Conversely, the IQI for metals showed that the ice was unsafe for human consumption. In terms of health risk assessment, the overall mean CDI (Chronic Daily Intake) and HQ (Hazard Quotient) values were in the order of Pb () > Ni (3.2) > Zn (2.3) > Fe (2.1) > Cr (1.6) > As (0.5) and Pb (7.4) > As (1.7) > Cr (0.5) > Ni (0.4 > Zn (0.008) > Fe (0.003), respectively. This study highlighted that routine monitoring of the water supplies available for making ice is required to protect public health.

The Enterics for Global Health (EFGH) Shigella Surveillance Study in Pakistan

Background

The Enterics for Global Health (EFGH) Shigella surveillance study is a longitudinal multicountry study that aims to estimate incidence rates and document consequences of Shigella diarrhea within 7 countries in Africa, Asia, and Latin America. In addition to a high incidence of childhood diarrhea, Pakistan is facing a problem of antimicrobial resistance in urban and peri-urban areas of Karachi.

Methods

In Pakistan, EFGH will be conducted in Karachi, which is one of the metropolitan cities bordering the Arabian Sea and has a diverse population of 1.6 million according to the 2017 population census. The study aims to enroll 1400 children aged 6-35 months over 2 years (2022-2024) from 6 health care facilities (Abbasi Shaheed Hospital, Khidmat-e-Alam Medical Centre, Sindh Government Hospital Korangi 5, Sindh Government Hospital Ibrahim Hyderi, Ali Akbar Shah VPT Center, and Bhains Colony VPT Center) situated in Nazimabad and Bin-Qasim town. Moreover, population enumeration and health care utilization surveys from a defined catchment area of health facilities will be conducted to estimate the Shigella diarrhea incidence rates.

Conclusions

The study will provide critical data to policy-makers about the burden of Shigella and antimicrobial resistance, which is essential for planning Shigella vaccine trials.

Spatio-temporal analysis of land use land cover change and its impact on land surface temperature of Sialkot City, Pakistan

The dynamic interplay between urbanization and its impacts on climate is a subject of recent concern, particularly in rapidly urbanizing cities of Pakistan. This research investigated the spatio-temporal effects of urban growth in terms of Land Use Land Cover changes on the thermal environment (Land Surface Temperature) of the Sialkot city, Pakistan using satellite data spanning four distinct time periods (1989, 2000, 2009 and 2020) and predicted changes for year 2030 by employing Cellular Automata Markov Chain Model. Satellite imagery (Landsat 5, 7 and 8) was processed, and maximum likelihood supervised classification was done to generate LULC maps for each of the aforementioned years. In addition to LULC classification, thermal bands of satellite data (for summer and winter) were processed to compute Land Surface Temperature (LST) of the city. The prediction of LULC changes and LST was done for year 2030 using Cellular Automata Markov Chain Model. The accuracy of classified and prediction maps was checked using Kappa Index. The LULC analysis revealed 4.14% increase in the built-up area and 3.43% decrease in vegetation cover of the city during 1989 to 2020. Both land covers are expected to change in the future (year 2030) by + 1.31% (built-up) and - 1.1% (vegetation). Furthermore, a declining trend in the barren land and water bodies was also observed over time. These LULC changes were found affecting the LST of study area. The transformation of vegetation cover into built-up area resulted in an increase in LST over time. A notable rise of 4.5 °C (summer) and 5.7 °C (winter) in the mean LST of Sialkot was observed during 1989 to 2020 and further increases are anticipated in year 2030. This study calls for attention of the policy makers to reduce human impact on the local climate of the city. The study will also help city developers in analyzing the urban population growth trend, finding suitable location to built new infrastructure by governmental authorities and how the rising temperature can affect energy demand and agriculture production of the city in future.

Traffic Signal Timing Optimization Model Based on Video Surveillance Data and Snake Optimization Algorithm

With the continued rapid growth of urban areas, problems such as traffic congestion and environmental pollution have become increasingly common. Alleviating these problems involves addressing signal timing optimization and control, which are critical components of urban traffic management. In this paper, a VISSIM simulation-based traffic signal timing optimization model is proposed with the aim of addressing these urban traffic congestion issues. The proposed model uses the YOLO-X model to obtain road information from video surveillance data and predicts future traffic flow using the long short-term memory (LSTM) model. The model was optimized using the snake optimization (SO) algorithm. The effectiveness of the model was verified by applying this method through an empirical example, which shows that the model can provide an improved signal timing scheme compared to the fixed timing scheme, with a decrease of 23.34% in the current period. This study provides a feasible approach for the research of signal timing optimization processes.

The Prospective Effects of Climate Change on Neglected Tropical Diseases in the Eastern Mediterranean Region: a Review

An increase in the annual daily temperature is documented and predicted to occur in the coming decades. Climate change has a direct effect and adverse impact on human health, as well as on multiple ecosystems and their species. The purpose of this paper is to review the effect of climate change on neglected tropical diseases including leishmaniasis, schistosomiasis, and lymphatic filariasis in the Eastern Mediterranean Region (EMR). A list of engine web searches was done; 280 full-text records were assessed for eligibility. Only 48 original records were included within the final selection for the review study. Most research results show an alteration of neglected diseases related to climate change influencing specifically the Eastern Mediterranean Region, in addition to the expectation of more effects at the level of vectors and reservoir whether its vector transmission route or its egg hatching and replication or even the survival of adult worms in the coming years. At the same time, not all articles related to the region interpret the direct or indirect effect of climate variations on these specific diseases. Although few studies were found describing some of climate change effects on neglected tropical diseases in the region, still, the region lacks research funding, technical, and mathematical model expertise regarding the direct effect of climate change on the ecosystems of these neglected tropical diseases.

Association between Dietary Diversity and Food Insecurity in Urban Households: A Cross-Sectional Survey of Various Ethnic Populations of Karachi, Pakistan

Background and Purpose

The world is experiencing a nutritional transition, yet some regions of South East Asia are still living under the shadows of catastrophic nutritional indicators. Pakistan bears a high dual burden of both communicable and chronic diseases. However, a major contributing factor of both is poor diet and nutrition. The causal pathway of stunting, underweight, wasting, and micronutrient deficiencies has beginnings in less dietary diversity and food insecurity. Current literature on Pakistan and other South Asian countries regarding food insecurity and dietary diversity largely focus on women and children aged less than 5 years; however, ethnic and cultural dynamics of the populace concerning their food and dietary practices in Pakistan have not been well explored. It is essential to have a clear insight into the factors involving malnutrition in different clusters, especially different cultures and ethnicities to target specific areas of interventional strategies versus a uniform approach for all. This study aimed to explore the level of food insecurity and dietary diversity in all major ethnic groups of Karachi, the largest city of Pakistan.

Methods

Using the multistage random sampling, 535 households from five major ethnic groups residing in Karachi were included in the study. To measure food insecurity and dietary diversity (primary and secondary outcome, respectively), we used a FAO standardized questionnaire (version 3, 2007) that was translated first into local languages, piloted, and employed to collect information.

Results

Severe food insecurity levels had an inverse relationship with the household dietary diversity, which persisted even after adjusting for other variables (β=−0.31, 95% CI=−0.65, −0.07). There was no statistically significant association of age, marital status, or education level on food diversity. The most food secure cultural people were those whose ancestors had migrated from India and were Urdu speaking communities, while Sindhi speakers were the least food secure community.

Conclusion

It is imperative to investigate more on the cultural causal factors leading to food insecurity to address the root causes of malnutrition and design new cultural-specific interventions that should be employed in large urban centers where different communities reside together.

Exploring willingness to pay for health insurance and preferences for a benefits package from the perspective of women from low-income households of Karachi, Pakistan

Background

Achieving universal health coverage (UHC) and reduction in out of pocket (OOP) expenditures on health, is a critical target of the Sustainable Development Goals (SDG). In low-middle income countries, micro-health insurance (MHI) schemes have emerged as a useful financing tool for laying grounds for Universal Health Coverage. The aim of this study was to provide evidence for designing a feasible health insurance scheme targeted at urban poor, by exploring preferences for an insurance benefits package and co-payments among women from low-income households in Karachi, Pakistan.

Methods

This was a descriptive cross-sectional study, conducted using household surveys between July–August 2015. A total of 167 female beneficiaries of Benazir Income Support Programme (BISP), a large-scale cash transfer scheme targeted at low-income households, were recruited in Karachi through a mix of convenience and snowball sampling. Hypothetical insurance benefits packages for a prospective health insurance scheme were formulated to capture respondents’ preferences for health insurance benefits package and co-payments. All data was analyzed using Stata (version 13).

Results

Respondents reporting expenditure on OPD and hospitalization in the last 2 weeks were 93.4 and 11.9% respectively. The highest median expenditure was incurred on medicines. Out of the proposed benefits package, a majority (53%) of the study participants opted for the comprehensive benefits package that provided coverage for emergency care, hospitalization, OPD consultation, diagnostic tests and transportation. For the co-payment plan, 38.9% participants preferred no co-payments that is 100% insurance coverage of medicines followed by hospitalization (25.9%). Nearly half of the respondents (49.4%) chose outpatient consultation for 50% co-payment. A majority of the participants (65.3%) agreed to 100% co-payment for the transportation cost.

Conclusion

Health insurance schemes can be introduced in urban areas, against collection of micro-payments, to prevent low-income households from facing financial catastrophe. A comprehensive benefits package covering emergency care, hospitalization, OPD consultation, diagnostic tests and transportation, is the most preferred among low-income beneficiaries.