A case report of Japanese encephalitis in Paracelis, Mountain Province, the Philippines.

On 12 September 2022, a 10-year-old female in Paracelis municipality, Mountain Province, the Philippines, without travel history outside the municipality, experienced acute onset of fever and a change in mental status with disorientation, an altered level of consciousness and new onset of seizures. She was hospitalized at the district hospital from 1 to 3 October 2022, before being transferred to the regional hospital. As diphtheria was originally suspected, the investigation team reviewed records and reports and interviewed key informants to gather additional information and organize case finding and contact tracing. The patient's condition was laboratory-confirmed for Japanese encephalitis virus infection. An environmental survey was carried out at the patient's residence to check for the presence of vectors and contributing factors. Exemplifying inadequate vaccination coverage for Japanese encephalitis virus in Mountain Province, the patient had not been vaccinated against the disease. It is recommended that vaccination campaigns be immediately implemented in the affected area and the surveillance system be strengthened for early detection and prompt response to the emergence of cases and outbreaks. Overall, the investigation highlighted the importance of strong surveillance and response systems for early detection and control of diseases, such as Japanese encephalitis virus. It also underscores the need for comprehensive vaccination programmes to prevent outbreaks and protect vulnerable populations.

Establishing an early warning surveillance system in jails in Calabarzon, the Philippines, 2021.

The Philippines' Republic Act 11332 (2020) mandates prisons, jails and detention centres to participate in disease surveillance, but currently no surveillance system exists in these facilities. This report aims to describe the piloting of an early warning disease surveillance system in 21 selected jails in Calabarzon from July to September 2021. Sites were selected based on congestion, proximity to health facilities and logistical capacity. Data sources, collection mechanisms and reporting tools were determined and health personnel were trained in the operation of the system. During the implementation period, the system detected 10 health events, with influenza-like illness and foodborne illness being the most common. Nine of these events were reported within 24 hours. The local health unit provided medications for clinical management and instructed jail nurses on infection prevention and control measures, including active case finding, the isolation of cases and the inspection of food handling. Twelve sites reported over 8 of the 10 weeks, with all sites reporting zero cases promptly. The challenges identified included insufficient workforce, slow internet speed and multitasking. It was concluded that the jail-based early warning surveillance system is feasible and functional, but the perceived benefits of jail management are crucial to the acceptability and ownership of the system. It is recommended to replicate the surveillance system in other penitentiaries nationwide.

Her village: experiences of drug-involved women in a female-only aftercare program in the Philippines.

PURPOSE: Women are exposed to vulnerabilities that can lead to drug use or hinder recovery. However, there is a dearth of studies on recovery programs for women. This study aims to add to the literature by examining the feasibility of a women-only aftercare program for recovering users in the Philippines. DESIGN/METHODOLOGY/APPROACH: The study used a mixed-method design with pre and post-program surveys used to measure changes in participants' recovery capital. Focused group discussions elicited participants' context, their reactions, perceived outcomes and suggestions on the program. FINDINGS: Women in the program shared narratives of pain, trauma and abuse before treatment. Participants reported significant improvements in personal, community and family recovery capital dimensions. The program enabled personal growth in the form of new knowledge, skills and self-confidence. The women-only program also provided a safe space for women, to receive support from other women, community members and family. However, the women continue to face continuing challenges related to stigma and discrimination and a lack of livelihood opportunities. RESEARCH LIMITATIONS/IMPLICATIONS: A limitation of the study was its small sample size and the lack of a control group. Another limitation was the variability in treatment received by the women, which could have affected overall outcomes. Future studies using a randomized control trial and longitudinal designs may provide more robust conclusions on the effectiveness of the program. PRACTICAL IMPLICATIONS: Given punitive contexts, gender-sensitive and trauma-informed programs and services for women involved in drug use could potentially mitigate the abuse, stigma and vulnerabilities they experience. ORIGINALITY/VALUE: This study contributes to the sparse literature on women-only aftercare, particularly in countries that criminalize drug use.

Major stoma complications in pediatric patients in a tertiary hospital in a low-middle-income country: a retrospective cohort study.

INTRODUCTION: Intestinal stomas are one of the most common parts of pediatric surgical care, and complications arising from it have significant impact on overall patient outcomes. However, data on major complications in low-middle-income countries remain limited. This pilot retrospective cohort study aimed to investigate the prevalence, types, and management of major stoma complications in pediatric patients at a tertiary government hospital in the Philippines. METHODS: Medical records of pediatric patients with major stoma complications classified as Clavien-Dindo III-V from June 2018 to June 2023 were reviewed. Patient-related factors (age, sex, diagnosis) and surgery-related factors (stoma type and location, surgeon expertise) were analyzed. Descriptive statistics characterized demographic profiles, while Chi-square and t tests analyzed categorical and continuous variables, respectively. Multivariable logistic regression evaluated independent associations with major stoma complications. RESULTS: Out of 1041 pediatric patients with stomas, 102 cases had major complications, representing a prevalence rate of 9.8%. Mortality directly attributed to stoma complications accounted for 1.3% of the total cases, or 14 deaths in 5 years. Neonates comprised a significant portion, primarily diagnosed with congenital conditions like anorectal malformation and Hirschsprung's disease. Ileostomies exhibited a higher incidence of major complications compared to other stoma types. Stomal prolapse and adhesive bowel obstruction are the most common reported stoma complications requiring surgical intervention while stoma revision is the most frequent corrective procedure. The median time from stoma creation to presentation of major complication was 14 months, with nearly half of the complications occurring within the first year. Only the presence of ileostomy had significant association with the development of major complications among the risk factors analyzed. CONCLUSIONS: This study provides useful insights into stoma complications in pediatric patients in a low-middle income country. Despite the lack of significant associations between the patient-related and surgeon-related factors, and major stoma complications, further investigation into other contributing factors is warranted. Improvements in data collection methods and prospective studies with larger sample sizes are recommended to enhance understanding and optimize care of major stoma complications. Addressing the challenges identified in this study could lead to a comprehensive and tailored approach to pediatric stoma care and their complications.

Pharmaceutical cost dynamics for the treatment of rifampicin-resistant tuberculosis in children and adolescents in South Africa, India, and the Philippines.

Rifampicin-resistant (RR) tuberculosis (TB) in children is a major global health concern but is often neglected in economics research. Accurate cost estimations across the spectrum of paediatric RR-TB treatment regimens are critical inputs for prioritisation and budgeting decisions, and an existing knowledge gap at local and international levels. This normative cost analysis was nested in a Phase I/II pharmacokinetics, safety, tolerability, and acceptability trial of TB medications in children in South Africa, the Philippines and India. It assessed the pharmaceutical costs of 36 childhood RR-TB regimens using combinations from 16 different medicines in 34 oral formulations (adult and child-friendly) in 11 weight bands in children <15 years of age. The analysis used local and Global Drug Facility pricing, and local and international guideline recommendations, including adaptions of BPaL and BPaLM regimens in adults. Costs varied significantly between regimen length, age/weight banding, severity of disease, presence of fluroquinolone resistance, and different country guideline recommendations. WHO recommended regimen costs ranged 12-fold: from US$232 per course (short regimen in non-severe disease) to US$2,761 (long regimen in severe, fluroquinolone-resistant disease). Regimen treating fluoroquinolone-resistant infection cost US$1,090 more than comparable WHO-recommended regimen. Providing child-friendly medicine formulations in <5-year-olds across all WHO-recommended regimens is expected to cost an additional $380 (range $212-$563) per child but is expected to have wider benefits including palatability, acceptability, adherence, tolerability, and dose accuracy. There were substantial differences in regimen affordability between countries when adjusted for purchasing power and domestic spending on health. Appropriate, effective, and affordable treatment options are an important component of the fight against childhood RR-TB. A comprehensive understanding of the cost and affordability dynamics of treatment options will enable national TB programs and global collaborations to make the best use of limited healthcare resources for the care of children with RR-TB.

Digital Adherence Technologies and Differentiated Care for Tuberculosis Treatment and Their Acceptability Among Persons With Tuberculosis, Health Care Workers, and Key Informants in the Philippines: Qualitative Interview Study.

BACKGROUND: Digital adherence technologies (DATs) are being studied to determine their potential to support tuberculosis (TB) treatment and address the shortcomings of directly observed therapy. Previous research has shown inconclusive results on whether DATs can enhance medication adherence among persons with TB. OBJECTIVE: This study aims to understand the acceptability of DATs, namely, medication labels and smart pillboxes, among persons with TB, health care workers (HCWs), and key informants (KIs) in the Philippines. The objective is to gain valuable insights that can inform the design and implementation of DATs in the Southeast Asian region, which meet the needs and preferences of end users. METHODS: Persons with TB, HCWs, and KIs were recruited from intervention facilities to participate in in-depth interviews conducted between March 2022 and January 2023. These interviews were transcribed and translated into English. A thematic analysis was carried out using NVivo software (Lumivero) to identify and analyze themes. Themes were then structured within a modified social-ecological model. RESULTS: A total of 25 persons with drug-sensitive TB and 20 HCWs or KIs were interviewed. Both groups emphasized that users' technology literacy level, financial conditions, and motivation to be cured determined how they interacted with the DAT. They also acknowledged that DATs helped foster their relationship with HCWs and enabled efficient treatment support. Concerning technology, persons with TB found DATs easy to use and able to reduce clinic visits. HCWs mentioned that DATs added to their workload but also allowed them to support users who missed doses. However, both groups experienced technical challenges with DATs. Regarding program implementation, users appreciated the clear explanations and demonstrations provided by HCWs. Yet, some users reported inconsistencies between DAT settings and the information provided. HCWs stressed the importance of comprehensive training and sufficient resources for effective program implementation in the future. At the community level, both groups noted that DATs and program design protected users' privacy and reduced the risk of stigma. Finally, users and HCWs shared various contextual factors that influenced their experience with DAT, including infrastructure challenges and the impact of the COVID-19 pandemic. CONCLUSIONS: In the Philippines, persons with TB and HCWs showed a high level of acceptance and satisfaction with the impact of DAT and program design. They expressed a desire for the continuation of DATs. The challenges encountered underscore the need for ongoing technological development to minimize malfunctions, enhance the capacity of health facilities, and improve infrastructure. DATs have demonstrated their ability to strengthen user-HCW relationships and protect users from stigmatization. Additional efforts are required to scale up the DAT program in the Philippines.

ChemsexPH: The association between chemsex, HIV status and adherence to antiretroviral therapy among men who have sex with men in the Philippines.

INTRODUCTION: Chemsex, the use of psychotropic drugs before or during sexual intercourse, is associated with various HIV risk factors, including condomless sex and reduced adherence to pre-exposure prophylaxis or antiretroviral therapy (ART). In the Philippines, there are still limited studies exploring the associations between chemsex, HIV status and ART adherence. This study aims to compare recent and lifetime chemsex engagement in association with self-reported HIV status among Filipino men who have sex with men (MSM). We further explored the association between chemsex and ART adherence among people living with HIV engaged in chemsex. METHODS: A cross-sectional online survey of 479 Filipino MSM was conducted from 3 August to 1 December 2019. Demographic profiles, sexual behaviours, drug use, history of sexually transmitted infections (STIs), chemsex engagement and HIV status were collected and analysed. Bivariable and multivariable logistic regression were employed to assess the association between self-reported HIV status and chemsex engagement. RESULTS: Among the 479 respondents, Filipino MSM engaged in drug use and chemsex were generally older compared to those not engaged in drug use and chemsex (average age 31-33 vs. 29 years old; p<0.05). Methamphetamine was the most common drug for people who reported using drugs. An HIV-positive status was associated with recent chemsex engagement (aOR = 5.18, p<0.05) and a history of STIs (aOR = 2.09, p<0.05). The subgroup analysis showed that 79% (166/200) of persons living with HIV were adherent to ART. There was no significant association found between chemsex and ART adherence in the logistic regression analyses. CONCLUSIONS: Chemsex behaviour, particularly recent chemsex engagement, is significantly associated with self-reported HIV status. The emerging data on MSM engaged in chemsex require integration of a more person-centred, comprehensive and robust harm reduction programmes into the existing combination prevention strategies in the country. Health education for Filipino MSM engaged in chemsex should prioritize raising awareness about methamphetamine effects and overdose risks, alongside proper medical management.

Local knowledge as the basis of disaster management and humanitarian assistance.

Recent policy discourse on the localisation of disaster management and humanitarian assistance lacks attention to the culture, history, and traditions of the Global South. This special issue of Disasters argues that it is imperative to recognise the dynamic, interactive, contested, and negotiated nature of local knowledge. Such local knowledge saves lives by enabling responders to situate ad hoc, one-off events such as disasters in the broader and deeper context of community relationships, thereby providing more appropriate and more effective aid. Through the cases of China, Japan, Indonesia, and the Philippines, this special issue examines such dynamic local knowledge using an analytical framework consisting of three manifestations of local knowledge, namely: social capital; contextual historical memories; and adaptation to new ideas. These three manifestations show the ways in which local knowledge creates local capacity, via which local, national, and international disaster respondents can centre their response coordination, and in turn, demonstrate how local capacity reformulates local knowledge.

Integrating Genetic Services in the Philippine Public Health Delivery System: The Value of Networks.

The delivery of genetic services in developing countries is faced with significant challenges, despite medical and technological advances globally. The Philippines, being an archipelago, faces even more challenges, with significant disparities in access to healthcare, and tertiary medical centers and specialists being concentrated in the major cities. The utilization of different networks for the integration of genetic services in the existing public health delivery system has been valuable. Using the well-established network of the national newborn screening program, genetic services have been successfully integrated into the delivery of healthcare, even at the grassroot level. Equitable access to healthcare, including genetic services, was highlighted and supported by the enactment of the Rare Disease Law in 2016. The support of the academe to assure the sustainability of services was evident in the establishment of a genetic counseling program to augment the work of a handful of clinical geneticists. Professional societies and support groups have been instrumental in identifying genetic conditions to be prioritized and lobbying for increased public awareness, leading to national programs and policies. This paper primarily discusses the value of networks in the delivery of genetic services, specifically newborn screening, programs for rare diseases, birth defects, and genetic counseling.

Integrating science-based and local ecological knowledge: a case study of mangrove restoration and rehabilitation projects in the Philippines.

Mangrove forest is an ecosystem-based solution for disaster risk reduction in the Philippines, but its historical deforestation has hampered its capacity to protect coastal communities. With the increasing occurrence of storm surge in the Philippines, mangrove reforestation projects have received renewed attention, but many have failed. Community participation was deemed to be essential in those projects that did well. Hence, this paper examines successful mangrove restoration and rehabilitation projects in the Philippines to find out how community participation contributed to the accomplishments. The study found that while the transfer of science-based ecological knowledge from project managers to the community is an important factor in ensuring successful initial planning and implementation, its integration into existing local ecological knowledge-'localisation' of science-based ecological knowledge or hybrid ecological knowledge formation-helped to facilitate long-term community-based mangrove management beyond project duration by empowering community members and enabling project acceptance and ownership. Still, continuous local institutional support is a necessary anchor for community resilience.

Bayesian phylogenetic analysis of Philippine languages supports a rapid migration of Malayo-Polynesian languages.

The Philippines are central to understanding the expansion of the Austronesian language family from its homeland in Taiwan. It remains unknown to what extent the distribution of Malayo-Polynesian languages has been shaped by back migrations and language leveling events following the initial Out-of-Taiwan expansion. Other aspects of language history, including the effect of language switching from non-Austronesian languages, also remain poorly understood. Here we apply Bayesian phylogenetic methods to a core-vocabulary dataset of Philippine languages. Our analysis strongly supports a sister group relationship between the Sangiric and Minahasan groups of northern Sulawesi on one hand, and the rest of the Philippine languages on the other, which is incompatible with a simple North-to-South dispersal from Taiwan. We find a pervasive geographical signal in our results, suggesting a dominant role for cultural diffusion in the evolution of Philippine languages. However, we do find some support for a later migration of Gorontalo-Mongondow languages to northern Sulawesi from the Philippines. Subsequent diffusion processes between languages in Sulawesi appear to have led to conflicting data and a highly unstable phylogenetic position for Gorontalo-Mongondow. In the Philippines, language switching to Austronesian in 'Negrito' groups appears to have occurred at different time-points throughout the Philippines, and based on our analysis, there is no discernible effect of language switching on the basic vocabulary.

Circulating cell-free RNA in blood as a host response biomarker for detection of tuberculosis.

Tuberculosis (TB) remains a leading cause of death from an infectious disease worldwide, partly due to a lack of effective strategies to screen and triage individuals with potential TB. Whole blood RNA signatures have been tested as biomarkers for TB, but have failed to meet the World Health Organization's (WHO) optimal target product profiles (TPP). Here, we use RNA sequencing and machine-learning to investigate the utility of plasma cell-free RNA (cfRNA) as a host-response biomarker for TB in cohorts from Uganda, Vietnam and Philippines. We report a 6-gene cfRNA signature, which differentiates TB-positive and TB-negative individuals with AUC = 0.95, 0.92, and 0.95 in test, training and validation, respectively. This signature meets WHO TPPs (sensitivity: 97.1% [95% CI: 80.9-100%], specificity: 85.2% [95% CI: 72.4-100%]) regardless of geographic location, sample collection method and HIV status. Overall, our results identify plasma cfRNA as a promising host response biomarker to diagnose TB.

There's an App for That: Exploring the Market for Contraceptive Fertility Tracking Apps in the Philippines.

For generations, women have relied on fertility awareness methods to plan and prevent pregnancy, for over a decade, many have been aided by digital tools to do so. New contraceptive fertility tracking apps (CFTAs)-that are backed by clinical efficacy trials to support their effectiveness as contraception-have the potential to enhance method choice and offer users a unique contraceptive option, but there is little evidence to inform the decisions around expanding access, particularly in low-and middle-income countries. We conducted a mixed methods study with quantitative online surveys (n = 1600) and qualitative interviews (n = 36) to explore the potential appeal of and demand for a hypothetical CFTA in one such market, the Philippines. Interest in using a CFTA was high among our Internet-engaged, urban study population, with 83.9% "definitely" or "probably" interested in using it. Across demographic profiles, respondents perceived the appeal of the method as "natural" and "convenient." A majority were willing to pay for the method, though notably at a price (5.20 USD) below that of currently available CFTAs. We discuss various important factors to be considered before bringing a method like this to new markets, including the potential implications of equity constraints in reaching a wider market and the unexpected prevalence of other period-tracking apps not intended as contraception being used in this market that could complicate any future roll-out. These issues could be explored further with additional research.

Pichia kudriavzevii as feed additive in Nile tilapia (Oreochromis niloticus) diet.

Yeasts are unicellular eukaryotic microorganisms extensively employed in various applications, notably as an alternative source of protein in feeds, owing to their nutritional benefits. Despite their potential, marine and mangrove yeast species used in the aquaculture industry have received little attention in the Philippines. Pichia kudriavzevii (A2B R1 ISO 3), sourced from bark samples, was selected and mass-produced due to its high protein content and amino acid profile. The dried biomass of P. kudriavzevii was incorporated into the diets of Nile tilapia (Oreochromis niloticus) juveniles at varying inclusion levels (0, 1, 2, and 4 g/kg diet) and its effect on their growth performance, body composition, and liver and intestinal morphology was assessed after 40 days of feeding. The groups that received P. kudriavzevii at a concentration of 2 g/kg diet exhibited higher final body weight, percent weight gain, and specific growth rate in comparison to the other treatment groups. Whole body proximate composition did not vary among the dietary groups. Intestinal and liver histopathology also indicated no abnormalities. These findings suggest the potential of ascomycetous P. kudriavzevii as a beneficial feed additive in Nile tilapia diets, warranting further investigation into its long-term effects and broader applications in fish culture.

APPaRENT 3: Asthma Patients' and Physicians' Perspectives on the Burden and Management of Asthma in Seven Countries.

INTRODUCTION: Asthma management is strongly dependent on physician and patient beliefs and perceptions about the disease and its long-term treatment. The APPaRENT 3 study was conducted to explore factors influencing treatment choice and to understand patients' and physicians' attitudes and perspectives on the use of controller inhalers in regular versus flexible dosing for asthma management. METHODS: This cross-sectional survey of patients with asthma and treating physicians was conducted in seven countries: Indonesia, Malaysia, Philippines, Thailand, Vietnam (patient survey only), Saudi Arabia, and the United Arab Emirates. Assessment was carried out through an online/face-to-face questionnaire, where patients' viewpoints were focused on their attitudes and beliefs about asthma and treatment adherence, whereas physicians' viewpoints were gathered on their attitudes and beliefs about asthma management, knowledge of and adherence to asthma treatment guidelines, and asthma treatment regimens. RESULTS: Overall, 1400 patients (mean age, 34 years) and 599 physicians (mean age, 43 years) were included in the survey. Physicians similarly prioritised symptom control (39%) and exacerbation reduction (40%) in moderate asthma, whereas patients prioritised symptom control (41%) over exacerbation reduction (22%). Although both groups (physicians, 86%; patients, 84%) perceived asthma as well-controlled, poor management was evident based on Asthma Control Test (ACT) scores (mean, 15.7; standard deviation, 4.14; 82% had an ACT score < 20) and high symptom burden (39% reported nighttime awakenings or early mornings ≥ 2 nights/week). Most patients (76%) with moderate asthma were prescribed regular dosing, with the most common treatment being inhaled corticosteroid (ICS)/long-acting ß2-agonist (LABA) with as-needed inhaled short-acting ß2-agonist (SABA; 20%). Among patients on maintenance and reliever therapy, 93% of patients received a separate inhaled reliever. CONCLUSIONS: Despite high symptom burden, patients overestimated their level of asthma control. Physicians prioritised controlling symptoms and reducing exacerbations as treatment goals for moderate asthma, often prescribing regular dosing with ICS/LABA with as-needed inhaled SABA.

Managing asthma depends a lot on what doctors and patients think about the illness and its long-term treatment. This study looked into what influences treatment decisions and what patients and doctors think about using inhalers regularly or on an as-needed basis to manage asthma across seven countries (Indonesia, Malaysia, Philippines, Thailand, Vietnam [patient survey only], Saudi Arabia, and the United Arab Emirates). In this study, patients with asthma and doctors managing asthma completed an online/face-to-face questionnaire. The study aimed to understand what patients think about asthma and their treatment plan. Meanwhile, the doctors were asked what they think about managing asthma and how much they apply clinical guidelines for treating patients with asthma. Doctors believed it is equally important to control symptoms and prevent worsening of symptoms in patients with moderate asthma, while patients cared more about controlling symptoms than preventing worsening of symptoms. While doctors and patients both regarded asthma as well-controlled, many patients had low Asthma Control Test scores and experienced a lot of symptoms, suggesting that they are poor perceivers of asthma control. Most patients with moderate asthma were given regular treatment, usually with inhaled corticosteroid combined with long-acting ß₂-agonist along with as-needed short-acting ß₂-agonist as a reliever. Most patients who were prescribed the same inhaler for regular use and as a reliever also had a separate inhaler for quick relief of symptoms. This study shows the need for patients and doctors to have better conversations about asthma, its treatments, and what to expect from them.

Identification of environmental, socioeconomic, water, sanitation, and hygiene (WaSH) factors associated with COVID-19 incidence in the Philippines: A nationwide modelling study.

Despite the implementation of non-pharmaceutical interventions, the threat of coronavirus disease 2019 (COVID-19) remains significant on a global scale. Identifying external factors contributing to its spread is crucial, especially given the World Health Organization's recommendation emphasizing access to water, sanitation, and hygiene as essential in curbing COVID-19. There is a notable discrepancy in access to sanitation facilities, particularly evident in low- and middle-income countries. However, there is a lack of quantitative assessments regarding these factors. This study examines various environmental, socioeconomic, water, sanitation, and hygiene factors and their associations with COVID-19 incidence. All regions in the Philippines were categorized into clusters based on socioeconomic factors. A conceptual structural equation model (SEM) was developed using domain knowledge. The best-fitting SEM for each cluster was determined, and associations between factors and COVID-19 incidence were estimated. The correlation analysis revealed that rainfall, minimum temperature, and relative humidity were positively correlated with weekly COVID-19 incidence in urban regions. Maximum temperature, mean temperature, wind speed, and wind direction were negatively correlated with weekly COVID-19 incidence in rural regions, with time lags of 0, 3, and 7 weeks. In urban regions (Cluster 1), factors such as urbanization rate (1.00), area (-0.93), and population (0.54) were found to be associated with weekly COVID-19 incidence. Conversely, in rural regions (Cluster 2), factors including area (0.17), basic sanitation (0.84), and wind direction (0.83) showed associations with weekly COVID-19 incidence. These factors were causally associated with a latent variable reflecting the hidden confounders associated with COVID-19 incidence. It is important to note that sanitation factors were associated only in rural regions. Improving access to sanitation facilities in rural regions of the Philippines is imperative to effectively mitigate disease transmission in future pandemics. Identification of the causal effect of unobserved confounders with COVID-19 incidence is recommended for future research.