Analysis of Excess Mortality Data at Different Altitudes During the COVID-19 Outbreak in Ecuador

A proposed analytical approach to estimate excess daily mortality rates in Ecuador

Background

The COVID-19 pandemic has proved deadly all over the globe; however, one of the most lethal outbreaks occurred in Ecuador.

Aims

This study aims to highlight the pandemic's impact on the most affected countries worldwide in terms of excess deaths per capita and per day.

Methods

An ecological study of all-cause mortality recorded in Ecuador was performed. To calculate the excess deaths relative to the historical average for the same dates in 2017, 2018, and 2019, we developed a bootstrap method based on the central tendency measure of mean. A Poisson fitting analysis was used to identify trends on officially recorded all-cause deaths and COVID-19 deaths. A bootstrapping technique was used to emulate the sampling distribution of our expected deaths estimator μ ⌢ d e a t h s by simulating the data generation and model fitting processes daily since the first confirmed case.

Results

In Ecuador, during 2020, 115,070 deaths were reported and 42,453 were cataloged as excess mortality when compared to 2017-2019 period. Ecuador is the country with the highest recorded excess mortality in the world within the shortest timespan. In one single day, Ecuador recorded 1,120 deaths (6/100,000), which represents an additional 408% of the expected fatalities.

Conclusion

Adjusting for population size and time, the hardest-hit country due to the COVID-19 pandemic was Ecuador. The mortality excess rate shows that the SARS-CoV-2 virus spread rapidly in Ecuador, especially in the coastal region. Our results and the proposed new methodology could help to address the real situation of the number of deaths during the initial phase of pandemics.

Epidemiological characterization of ischemic heart disease at different altitudes: A nationwide population-based analysis from 2011 to 2021 in Ecuador

BACKGROUND

Cardiovascular diseases, including ischemic heart disease, are the leading cause of premature death and disability worldwide. While traditional risk factors such as smoking, obesity, and diabetes have been thoroughly investigated, non-traditional risk factors like high-altitude exposure remain underexplored. This study aims to examine the incidence and mortality rates of ischemic heart disease over the past decade in Ecuador, a country with a diverse altitude profile spanning from 0 to 4,300 meters.

METHODS

We conducted a geographic distribution analysis of ischemic heart disease in Ecuador, utilizing hospital discharge and mortality data from the National Institute of Census and Statistics for the years 2011-2021. Altitude exposure was categorized according to two distinct classifications: the traditional division into low (< 2,500 m) and high (> 2,500 m) altitudes, as well as the classification proposed by the International Society of Mountain Medicine, which delineates low (< 1,500 m), moderate (1,500-2,500 m), high (2,500-3,500 m), and very high (3,500-5,800 m) altitudes.

FINDINGS

From 2011-2021, we analyzed 49,765 IHD-related hospital admissions and 62,620 deaths. Men had an age-adjusted incidence rate of 55.08/100,000 and a mortality rate of 47.2/100,000, compared to 20.77/100,000 and 34.8/100,000 in women. Incidence and mortality surged in 2020 by 83% in men and 75% in women. Altitudinal stratification revealed higher IHD rates at lower altitudes (<2500 m), averaging 61.65 and 121.8 per 100,000 for incidence and mortality, which declined to 25.9 and 38.5 at elevations >2500 m. Men had more pronounced rates across altitudes, exhibiting 138.7% and 150.0% higher incidence at low and high altitudes respectively, and mortality rates increased by 48.3% at low altitudes and 23.2% at high altitudes relative to women.

CONCLUSION

Ecuador bears a significant burden of ischemic heart disease (IHD), with men being more affected than women in terms of incidence. However, women have a higher percentage of mortality post-hospital admission. Regarding elevation, our analysis, using two different altitude cutoff points, reveals higher mortality rates in low-altitude regions compared to high-altitude areas, suggesting a potential protective effect of high elevation on IHD risk. Nevertheless, a definitive dose-response relationship between high altitude and reduced IHD risk could not be conclusively established.

Poor regulation, desperation, and misinformation, a countrywide analysis of self-medication and prescription patterns in Ecuador during the COVID-19 pandemic

BACKGROUND

The rapid spread of the SARS-CoV-2 virus during the early phase of the pandemic led to an unprecedented global health crisis. Various factors have influenced self-medication practices among the general population and unsubstantiated prescribing practices among healthcare professionals.

OBJECTIVE

This study aimed to describe trends in the purchase and sale of medicines during the COVID-19 pandemic period (2020-2022) in Ecuador, by comparing them with pre-pandemic periods.

METHODS

In this study, a cross-sectional design was employed to conduct a comprehensive analysis of 28 pharmacological groups, categorized according to the Anatomical Therapeutic Chemical Classification (ATC). Utilizing an integrated drug consumption database, the study examined physician prescribing data, medicine usage, and spending levels in Ecuador during the COVID-19 pandemic. The analysis involved computing absolute differences in monthly resolution, calculating excessive expenditure in comparison to previous yearly averages, and using Defined Daily Dose (DDD) methodology for internationally comparable results. Furthermore, a correlation analysis was performed to investigate potential associations between prescribed and consumed medicines and the number of new cases and deaths.

RESULTS

In Ecuador, the average yearly expenditure among these groups prior to the pandemic (2017-2019) amounted to $150,646,206 USD, whereas during 2020 and 2021, the same groups represented a total expenditure of $228,327,210, reflecting a significant increase. The excess expenditure during this period reached 51.4%, equivalent to $77,681,004 USD. Notably, 13% of this expenditure consisted of Over the Counter (OTC) Medicines. The study also identified a remarkable surge in sales of ivermectin, which increased by 2,057%, and hydroxychloroquine, which increased by 171%, as measured by DDD.

CONCLUSIONS

This study highlights the substantial consumption of medicines by the population in Ecuador during the pandemic. It is concerning that many medications were sold without proven therapeutic indications, indicating that misinformation and desperation may have led to improper prescribing by physicians and patients resorting to ineffective drugs. Moreover, since the sale of these therapeutic drugs requires a prescription, poor regulation, and a lack of control within pharmacies likely contributed to such practices.

Receiver operating characteristic (ROC) to determine cut-off points of clinical and biomolecular markers to discriminate mortality in severe COVID-19 living at high altitude

BACKGROUND

In 2020, Ecuador had one of the highest death rates because of COVID-19. The role of clinical and biomolecular markers in COVID disease prognosis, is still not well supported by available data. In order for these markers to have practical application in clinical decision-making regarding patient treatment and prognosis, it is necessary to know an optimal cut-off point, taking into consideration ethnic differences and geographic conditions.

AIM

To determine the value of clinical and biomolecular markers, to predict mortality of patients with severe COVID-19 living at high altitude.

METHODS

In this study, receiver operating characteristic (ROC) curves, area under the curve (AUC) of ROC, sensitivity, specificity and likelihood ratios were calculated to determine levels of clinical and biomolecular markers that best differentiate survivors versus non-survivors in severe COVID subjects that live at a high altitude setting.

RESULTS

Selected cut-off values for ferritin (≥ 1225 ng/dl, p = 0.026), IL-6 (≥ 11 pg/ml, p = 0.005) and NLR (≥ 22, p = 0.008) at 24 h, as well as PaFiO2 (≤ 164 mmHg, p = 0.015), NLR (≥ 16, p = p = 0.013) and SOFA (≥ 6, p = 0.031) at 72 h, appear to have good discriminating power to differentiate survivors versus non-survivors. Additionally, odds ratios for ferritin (OR = 3.38); IL-6 (OR = 17.07); PaFiO2 (OR = 4.61); NLR 24 h (OR = 4.95); NLR 72 h (OR = 4.46), and SOFA (OR = 3.77) indicate increased risk of mortality when cut-off points were taken into consideration.

CONCLUSIONS

We proposed a straightforward and understandable method to identify dichotomized levels of clinical and biomolecular markers that can discriminate between survivors and non-survivors patients with severe COVID-19 living at high altitudes.

Altitude and COVID-19 in Colombia: An updated analysis accounting for potential confounders

We assessed the relationship between the altitude of municipalities and the incidence, mortality, and fatality from COVID-19 and excess of mortality in Colombia between 2020 and 2022. We conducted an ecologic study including all 1122 municipalities in Colombia and used categories of altitude as main independent variable. We fit multivariable regression models for incidence, mortality, fatality rates, and excess of mortality controlling for several variables at municipality level. There was a higher incidence rate, similar mortality rate and lower case-fatality rate for COVID-19 during 2020-2022 in municipalities in the upper category of altitude (>=2500 masl) compared to the lower category (<1000 masl). The excess of mortality was lower but not statistically different in municipalities in the upper category of altitude, and significantly lower in the intermediate altitude category compared to the lowlands. Our findings provide evidence that municipalities with high altitude had similar mortality rate, and lower case-fatality rate and excess of mortality for COVID-19 compared to lowlands in Colombia.

A U-shaped protection of altitude against mortality and infection of COVID-19 in Peru: an ecological study

BACKGROUND

The COVID-19 pandemic has affected the world in multiple ways and has been a challenge for the health systems of each country. From the beginning, risk factors for the severity and mortality of the disease were considered, as the spread of the virus was related to the living conditions of each population.

METHODS

In this ecological study we have evaluated the role of geography, precisely the altitude above sea level in the incidence and mortality of COVID-19 in Peru. Incidence and mortality data were taken from the open-access database of the government of Peru until March 2021. COVID-19 cases and COVID-19 mortality were treated as cases/density population and 1000 x cases/inhabitants while altitude was treated as continuous and as a categorical variable divided in 7 categories. The relationship between COVID-19 cases or deaths for COVID-19 and altitude as continuous variable was determined using Spearman correlation test. Meanwhile when altitude was considered as a categorical variable, Poisson regression or negative binomial analyses were applied.

RESULTS

A significant inverse correlation was found between COVID-19 cases by population density and altitude (r=-0.37 p < 0.001). By altitude categories, the lowest risk for infection was observed between 3,000 and 3,500 m (IRR 0.08; 95% CI 0.05,0.12). Moreover, we found an inverse correlation between altitude and COVID-19 mortality (r=-0.39 p < 0.001). Also, the lowest risk for mortality was observed between 3,000 and 3,500 m (IRR 0.12; 95%CI 0.08; 0.18). Similar results were found when analyses were adjusted for inhabitants and stratified by sex.

CONCLUSION

This study reports an inverse relationship between COVID-19 incidence and mortality with respect to the altitude of residence, particularly, a u-shaped protection is shown, with a highest benefit between 3000 and 3500 m. The possibility of using hypoxia as an alternative treatment requires more complex studies that should allow knowing the physiological and environmental mechanisms of the protective role.

Solar desalination/purification (solar stills, humidification-dehumidification, solar disinfection) in high altitude during COVID19: Insights of gastrointestinal manifestations and systems' mechanism

From the starting of the pandemic different transmission routes of the pathogen was brought into the spotlight by researchers from different disciplines. This matter in high-altitudes was more boosted as the main parameters were not exactly realized. In this review we are about to highlight the possibility of consuming contaminated water generated form solar water desalination/disinfection systems in highlands. Three systems including solar still, solar disinfection (which experimented by the authors in 2019 in high altitude) and humidification-dehumidification were consider in this context. Ascribe to the risks of pathogens transmission in solar desalination/disinfection systems where the water resources are heavily polluted in every corner of the world, highlighting the risk of consuming water in high-altitude where there are many other parameters associated with spread of pathogen is of great importance. As it was reported, reliability of solar desalination and solar water disinfections systems against contaminated water by the novel coronavirus remained on the question because the virus can be transmitted by vapor in solar stills due to tiny particle size (60-140 nm) and would not be killed by solar disinfections due to low-temperature of operation <40 °C while for HDH contamination of both water and air by sars-cov-2 could be a concern. Although the SARS-CoV-2 is not a waterborne pathogen, its capability to replicate in stomach and infection of gastrointestinal glandular suggested the potential of transmission via fecal-oral. Eventually, it was concluded that using solar-based water treatment as drinking water in high altitude regions should be cautiously consider and recommendations and considerations are presented. Importantly, this critical review not only about the ongoing pandemic, but it aims is to highlight the importance of produced drinking water by systems for future epidemic/pandemic to prevent spread and entering a pathogen particularly in high-altitude regions via a new routes.

Biomarkers as predictors of mortality in critically ill obese patients with COVID-19 at high altitude

BACKGROUND

Obesity is a common chronic comorbidity of patients with COVID-19, that has been associated with disease severity and mortality. COVID-19 at high altitude seems to be associated with increased rate of ICU discharge and hospital survival than at sea-level, despite higher immune levels and inflammation. The primary aim of this study was to investigate the survival rate of critically ill obese patients with COVID-19 at altitude in comparison with overweight and normal patients. Secondary aims were to assess the predictive factors for mortality, characteristics of mechanical ventilation setting, extubation rates, and analytical parameters.

METHODS

This is a retrospective cohort study in critically ill patients with COVID-19 admitted to a hospital in Quito-Ecuador (2,850 m) from Apr 1, 2020, to Nov 1, 2021. Patients were cathegorized as normal weight, overweight, and obese, according to body mass index [BMI]).

RESULTS

In the final analysis 340 patients were included, of whom 154 (45%) were obese, of these 35 (22.7%) were hypertensive and 25 (16.2%) were diabetic. Mortality in obese patients (31%) was lower than in the normal weight (48%) and overweight (40%) groups, but not statistically significant (p = 0.076). At multivariable analysis, in the overall population, older age (> 50 years) was independent risk factor for mortality (B = 0.93, Wald = 14.94, OR = 2.54 95%CI = 1.58-4.07, p < 0.001). Ferritin and the neutrophil/lymphocyte ratio were independent predictors of mortality in obese patients. Overweight and obese patients required more positive and-expiratory pressure compared to normal-weight patients. In obese patients, plateau pressure and mechanical power were significantly higher, whereas extubation failure was lower as compared to overweight and normal weight.

CONCLUSIONS

This preliminary study suggests that BMI was not associated with mortality in critically ill patients at high altitude. Age was associated with an increase in mortality independent of the BMI. Biomarkers such as ferritin and neutrophils/lymphocytes ratio were independent predictors of mortality in obese patients with COVID-19 at high altitude.

Analysis of fatality impact and seroprevalence surveys in a community sustaining a SARS-CoV-2 superspreading event

There is an ongoing debate on the COVID-19 infection fatality rate (IFR) and the impact of COVID-19 on overall population mortality. Here, we addressed these issues in a community in Germany with a major superspreader event analyzing deaths over time and auditing death certificates in the community.18 deaths that occurred within the first six months of the pandemic had a positive test for SARS-CoV-2. Six out of 18 deaths had non-COVID-19 related causes of death (COD). Individuals with COVID-19 COD typically died of respiratory failure (75%) and tended to have fewer reported comorbidities (p = 0.029). Duration between first confirmed infection and death was negatively associated with COVID-19 being COD (p = 0.04). Repeated seroprevalence essays in a cross-sectional epidemiological study showed modest increases in seroprevalence over time, and substantial seroreversion (30%). IFR estimates accordingly varied depending on COVID-19 death attribution. Careful ascertainment of COVID-19 deaths is important in understanding the impact of the pandemic.

Factors Associated with COVID-19 Death in a High-Altitude Peruvian Setting during the First 14 Months of the Pandemic: A Retrospective Multicenter Cohort Study in Hospitalized Patients

Risk factors for COVID-19 death in high-altitude populations have been scarcely described. This study aimed to describe risk factors for COVID-19 death in three referral hospitals located at 3399 m in Cusco, Peru, during the first 14 months of the pandemic. A retrospective multicenter cohort study was conducted. A random sample of ~50% (1225/2674) of adult hospitalized patients who died between 1 March 2020 and 30 June 2021 was identified. Of those, 977 individuals met the definition of death by COVID-19. Demographic characteristics, intensive care unit (ICU) admission, invasive respiratory support (IRS), disease severity, comorbidities, and clinical manifestation at hospital admission were assessed as risk factors using Cox proportional-hazard models. In multivariable models adjusted by age, sex, and pandemic periods, critical disease (vs. moderate) was associated with a greater risk of death (aHR: 1.27; 95%CI: 1.14-1.142), whereas ICU admission (aHR: 0.39; 95%CI: 0.27-0.56), IRS (aHR: 0.37; 95%CI: 0.26-0.54), the ratio of oxygen saturation (ROX) index ≥ 5.3 (aHR: 0.87; 95%CI: 0.80-0.94), and the ratio of SatO2/FiO2 ≥ 122.6 (aHR: 0.96; 95%CI: 0.93-0.98) were associated with a lower risk of death. The risk factors described here may be useful in assisting decision making and resource allocation.

Disparities in COVID-19 incidence and fatality rates at high-altitude

Background

SARS-CoV-2 has affected every demography disproportionately, including even the native highland populations. Hypobaric-hypoxic settings at high-altitude (HA, >2,500 masl) present an extreme environment that impacts the survival of permanent residents, possibly including SARS-CoV-2. Conflicting hypotheses have been presented for COVID-19 incidence and fatality at HA.

Objectives

To evaluate protection or risk against COVID-19 incidence and fatality in humans under hypobaric-hypoxic environment of high-altitude (>2,501 masl).

Methods

Global COVID-19 data of March 2020-21, employed from official websites of the Indian Government, John Hopkins University, and Worldometer were clustered into 6 altitude categories. Clinical cofactors and comorbidities data were evaluated with COVID-19 incidence and fatality. Extensive comparisons and correlations using several statistical tools estimated the risk and protection.

Results

Of relevance, data analyses revealed four distinct responses, namely, partial risk, total risk, partial protection, and total protection from COVID-19 at high-altitude indicating a mixed baggage and complexity of the infection. Surprisingly, it included the countries within the same geographic region. Moreover, body mass index, hypertension, and diabetes correlated significantly with COVID-19 incidence and fatality rate (P ≤ 0.05).

Conclusions

Varied patterns of protection and risk against COVID-19 incidence and fatality were observed among the high-altitude populations. It is though premature to generalize COVID-19 effects on any particular demography without further extensive studies.

Severe Chagas disease in Ecuador: a countrywide geodemographic epidemiological analysis from 2011 to 2021

Background

Chagas disease is a neglected and often forgotten tropical disease caused by the Trypanosoma cruzi. This parasite can be transmitted through the direct contact of human skin with feces and urine of the triatomine insect. According to the World Health Organization (WHO), an estimated 6-7 million people are infected worldwide, killing at least 14,000 every year. The disease has been reported in 20 of the 24 provinces of Ecuador, with El Oro, Guayas, and Loja being the most affected.

Methodology

We analyzed the morbidity and mortality rates of severe Chagas disease in Ecuador on a nationwide, population-based level. Hospitalization cases and deaths were also examined based on altitude, including low (< 2,500 m) and high (> 2,500 m) altitudes, according to the International Society. Data was retrieved from the National Institute of Statistics and Census hospital admissions and in-hospital mortality databases from 2011 to 2021.

Results

A total of 118 patients have been hospitalized in Ecuador since 2011 due to Chagas disease. The overall in-hospital mortality rate was 69.4% (N = 82). Men have a higher incidence rate (4.8/1,000,000) than women, although women have a significantly higher mortality rate than men (6.9/1,000,000).

Conclusion

Chagas disease is a severe parasitic condition that primarily affects rural and poorer areas of Ecuador. Men are more likely to be infected due to differences in work and sociocultural activities. Using average elevation data, we conducted a geodemographic analysis to assess incidence rates by altitude. Our findings indicate that the disease is more common at low and moderate altitudes, but recent increases in cases at higher altitudes suggest that environmental changes, such as global warming, could be driving the proliferation of disease-carrying vectors in previously unaffected areas.

The deadly impact of COVID-19 among children from Latin America: The case of Ecuador

Background

The SARS-CoV-2 pandemic remains a critical global health concern, with older adults being the most vulnerable group. Nonetheless, it is crucial to recognize that COVID-19 has caused numerous deaths in children worldwide. Emerging evidence indicates that infants and breastfeeding children, particularly those aged below one year, face a greater risk of hospitalization and mortality than older children with COVID-19.

Objective

This study aimed to describe the epidemiology of COVID-19 among children during the early phase of the pandemic in Ecuador.

Methods

We conducted a country-wide population-based analysis of the epidemiology of COVID-19, using incidence and mortality data reported from Ecuador between February 15, 2020 and May 14 2021. Measurements of frequency, central tendency, dispersion, and absolute differences were calculated for all categorical and continuous variables.

Results

At least 34,001 cases (23,587 confirmed cases, 5,315 probable and 5,099 suspected) and 258 COVID-19 related deaths have been reported among children in Ecuador during the first 16 months of the pandemic. The overall incidence rate was 612 cases per 100,000 children, the mortality rate was 3 per 100,000, while the case fatality rate was 0.76%. The highest risk group for infection was children and adolescents between 15 and 19 years of age; however, the highest mortality rate occurred in children under one year of age. The largest provinces, such as Pichincha, Guavas and Manabí, were the ones that reported the highest number of cases, 27%, 12.1% and 10.8%, respectively.

Conclusions

This study is the first to report on COVID-19 epidemics among children in Ecuador. Our findings reveal that younger children have a lower risk of SARS-CoV-2 infection, but a higher risk of mortality compared to older children and adolescents. Additionally, we observed significant disparities in infection rates and outcomes among children living in rural areas, those with comorbidities, and those from indigenous ethnic groups.

Health Benefits of Residence at Moderate Altitude Do Not Reduce COVID-19 Mortality

Moderate altitude (1000−2000 m above sea level) residence is emerging as a protective factor from the mortality of various causes, including of cardiovascular diseases. Conversely, mortality from certain respiratory diseases is higher at these altitudes than in lowlands. These divergent outcomes could indicate either beneficial or detrimental effects of altitude on the mortality of COVID-19 that primarily infects the respiratory tract but results in multi-organ damage. Previous epidemiological data indeed suggest divergent outcomes of moderate to high altitude residence in various countries. Confounding factors, such as variations in the access to clinical facilities or selection biases of investigated populations, may contribute to the equivocation of these observations. We interrogated a dataset of the complete population of an Alpine country in the center of Europe with relatively similar testing and clinical support conditions across altitude-levels of residence (up to around 2000 m) to assess altitude-dependent mortality from COVID-19 throughout 2020. While a reduced all-cause mortality was confirmed for people living higher than 1000 m, no differences in the mortality from COVID-19 between the lowest and the highest altitude regions were observed for the overall population and the population older than 60 years as well. Conversely, COVID-19 mortality seems to have been reduced in the very old (>85 years) women at moderate altitudes.

High rates of SARS-CoV-2 infection in funeral home workers in Ecuador: Is it an occupational risk for COVID-19?

Aim

The COVID-19 outbreak has already caused more than 6.5 million deaths, overwhelming health systems worldwide. The unusual demand for funeral home services could make these workers a potential risk group for occupational exposure to SARS-CoV-2 associated with corpses management for COVID-19 patients.

Methodology

This is a cross-sectional study aimed to describe the infection rate of SARS-CoV-2 in funeral home staff by testing them with RT-qPCR in Quito, Ecuador. A total of 232 funeral home workers, representing more than 40% of funeral home personnel in Quito, were included in the study, in June 2020, immediately after the population lockdown was lifted in Ecuador.

Results

A total of 48 individuals tested positive for SARS-CoV-2, yielding an infection rate of 20.7%. The SARS-CoV-2 infection rate was 18.1 and 20.0% among personnel managing corpses or not managing corpses, respectively. Among the SARS-CoV-2 positive patients, 81.3% reported no symptoms related to COVID-19, and 3 individuals had high viral loads over 108 copies/ml.

Conclusion

The high SARS-CoV-2 infection rate in funeral home staff suggested a potential occupational risk for COVID-19 but not related to corpses management. Public health guidelines for safe corpses management for COVID-19 victims and safe funeral services should be reinforced.

Long COVID at Different Altitudes: A Countrywide Epidemiological Analysis

BACKGROUND

Several reports from around the world have reported that some patients who have recovered from COVID-19 have experienced a range of persistent or new clinical symptoms after a SARS-CoV-2 infection. These symptoms can last from weeks to months, impacting everyday functioning to a significant number of patients.

METHODS

A cross-sectional analysis based on an online, self-reporting questionnaire was conducted in Ecuador from April to July 2022. Participants were invited by social media, radio, and TV to voluntarily participate in our study. A total of 2103 surveys were included in this study. We compared socio-demographic variables and long-term persisting symptoms at low (<2500 m) and high altitude (>2500 m).

RESULTS

Overall, 1100 (52.3%) responders claimed to have Long-COVID symptoms after SARS-CoV-2 infection. Most of these were reported by women (64.0%); the most affected group was young adults between 21 to 40 years (68.5%), and most long-haulers were mestizos (91.6%). We found that high altitude residents were more likely to report persisting symptoms (71.7%) versus those living at lower altitudes (29.3%). The most common symptoms were fatigue or tiredness (8.4%), hair loss (5.1%) and difficulty concentrating (5.0%). The highest proportion of symptoms was observed in the group that received less than 2 doses.

CONCLUSIONS

This is the first study describing post-COVID symptoms' persistence in low and high-altitude residents. Our findings demonstrate that women, especially those aging between 21-40, are more likely to describe Long-COVID. We also found that living at a high altitude was associated with higher reports of mood changes, tachycardia, decreased libido, insomnia, and palpitations compared to lowlanders. Finally, we found a greater risk to report Long-COVID symptoms among women, those with previous comorbidities and those who had a severer acute SARS-CoV-2 infection.

A comparative analysis of SARS-CoV-2 viral load across different altitudes

SARS-CoV-2 has spread throughout the world, including areas located at high or very high altitudes. There is a debate about the role of high altitude hypoxia on viral transmission, incidence, and COVID-19 related mortality. This is the first comparison of SARS-CoV-2 viral load across elevations ranging from 0 to 4300 m. To describe the SARS-CoV-2 viral load across samples coming from 62 cities located at low, moderate, high, and very high altitudes in Ecuador. An observational analysis of viral loads among nasopharyngeal swap samples coming from a cohort of 4929 patients with a RT-qPCR test positive for SARS-CoV-2. The relationship between high and low altitude only considering our sample of 4929 persons is equal in both cases and not significative (p-value 0.19). In the case of low altitude, adding the sex variable to the analysis, it was possible to find a significative difference between men and women (p-value < 0.05). Considering initially sex and then altitude, it was possible to find a significative difference between high and low altitude for men (p-value 0.05). There is not enough evidence to state that viral load is affected directly by altitude range but adding a new variable as sex in the analysis shows that the presence of new variables influences the relationship of altitude range and viral load. There is no evidence that viral loads (Ct and copies/ml) differ at low or high altitude. Using sex as a co-factor, we found that men have higher viral loads than women at low and moderate altitude locations, while living at high altitude, no differences were found. When Ct values were aggregated by low, moderate, and high viral load, we found no significant differences when sex was excluded from the analysis. We conclude that viral load is not directly affected by altitude, but COVID-19 incidence and mortality are rather affected by socio-demographic and idiosyncratic dynamics.

High-altitude is associated with better short-term survival in critically ill COVID-19 patients admitted to the ICU

BACKGROUND

Multiple studies have attempted to elucidate the relationship between chronic hypoxia and SARS-CoV-2 infection. It seems that high-altitude is associated with lower COVID-19 related mortality and incidence rates; nevertheless, all the data came from observational studies, being this the first one looking into prospectively collected clinical data from severely ill patients residing at two significantly different altitudes.

METHODS

A prospective cohort, a two-center study among COVID-19 confirmed adult patients admitted to a low (sea level) and high-altitude (2,850 m) ICU unit in Ecuador was conducted. Two hundred and thirty confirmed patients were enrolled from March 15th to July 15th, 2020.

RESULTS

From 230 patients, 149 were men (64.8%) and 81 women (35.2%). The median age of all the patients was 60 years, and at least 105 (45.7%) of patients had at least one underlying comorbidity, including hypertension (33.5%), diabetes (16.5%), and chronic kidney failure (5.7%). The APACHE II scale (Score that estimates ICU mortality) at 72 hours was especially higher in the low altitude group with a median of 18 points (IQR: 9.5-24.0), compared to 9 points (IQR: 5.0-22.0) obtained in the high-altitude group. There is evidence of a difference in survival in favor of the high-altitude group (p = 0.006), the median survival being 39 days, compared to 21 days in the low altitude group.

CONCLUSION

There has been a substantial improvement in survival amongst people admitted to the high-altitude ICU. Residing at high-altitudes was associated with improved survival, especially among patients with no comorbidities. COVID-19 patients admitted to the high-altitude ICU unit have improved severity-of-disease classification system scores at 72 hours.