Positive Individual Research Articles

Risk factors for SARS-CoV-2 infection and severe COVID-19 in unvaccinated solid organ transplant recipients

The role of immunosuppressive therapy on SARS-CoV-2 infection risk and COVID-19 severity remains unclear in unvaccinated solid organ transplant recipients. We included 1957 organ transplant recipients between July 2020 and April 2021 to analyze whether baseline immunosuppressive therapy and other risk factors are associated with SARS-CoV-2 infection and severe COVID-19. In total, 247 (12.6%) had SARS-CoV-2 (defined as positive nasopharyngeal swab and/or positive antibody titer). Of these, 57 (23.1%) had severe COVID-19, defined as oxygen supplementation, intensive care unit admission or death. Multivariable analysis identified diabetes (hazard ratio (HR) 1.39 (95% confidence interval (CI) 1.05–1.83)), chronic lung disease (HR 1.71 (95% CI 1.13–2.60)) and contact with a COVID-19 positive individual (HR 3.61 (95% CI 2.61–4.99) as independent risk factors for SARS-CoV-2 infection. There was no association between immunosuppressive therapy and infection risk. Severe COVID-19 was multivariably associated with hypertension (OR 5.45 (95% CI 1.66–17.84)), chronic kidney disease (OR 3.55 (95% CI 1.75–7.19)), corticosteroid use (OR 2.93 (95% CI 1.03–2.55)) and having a COVID-19 positive housemate (OR 6.77 (95% CI 2.65–17.28)). In conclusion, baseline corticosteroid use, but no other immunosuppressive agent, is independently associated with severe COVID-19 in unvaccinated SOT recipients after correction for hypertension, chronic kidney disease, housemates affected by COVID-19 and transplant type.

Prevalence and Associated Risk Factors of Tuberculosis among Smear Positive Contact Individuals in Port Sudan

Background: Tuberculosis is a necrotizing granulomatous multisystem infectious disease that caused by mycobacterium, mainly mycobacterium tuberculosis, It is a serious global health problem that represent the commonest infectious cause of death. Many risk factors contribute in spread of tuberculosis, these factors include environmental factors, host factors and factors related to organism. Contact with smear positive patients is a major risk factors as every infectious patient can transmit the organism to ten to fifteen persons; therefore, contact tracing being an important element in DOTS (Direct Observed Therapy Strategy), because early detection and early management of cases prevent complication and improve the outcome. Objectives: This study aims to determine the prevalence and assess risk factors of tuberculosis among TB smear positive contact whose registered in Port Sudan chest hospital TBMU center during third and fourth quarters; June to December 2023. Methodology: This is a descriptive cross sectional community base study, Port Sudan, eastern Sudan, from June 2023 to December 2023. Result: The study shows that prevalence of tuberculosis among smear positive contact individual is 4.6%s. And it shows other associated risk factors has a role in spread of the disease. Conclusion: The prevalence of tuberculosis among smear positive contact individuals in Port Sudan is low comparing to literature and other studies due to strong tuberculosis program and stigma also play a role in this reduction. Tuberculosis spread more among female and elder contact as the spend more time in the home. And immunosuppression, poor ventilation and crowded household play an essential role in spread of tuberculosis.

Prevalence and Associated Risk Factors of Tuberculosis among Smear positive Contact Individuals in Port Sudan

Background: Tuberculosis is a necrotizing granulomatous multisystem infectious disease that caused by mycobacterium, mainly mycobacterium tuberculosis, It is a serious global health problem that represent the commonest infectious cause of death. Many risk factors contribute in spread of tuberculosis, these factors include environmental factors, host factors and factors related to organism. Contact with smear positive patients is a major risk factors as every infectious patient can transmit the organism to ten to fifteen persons; therefore, contact tracing being an important element in DOTS (Direct Observed Therapy Strategy), because early detection and early management of cases prevent complication and improve the outcome. Objectives: This study aims to determine the prevalence and assess risk factors of tuberculosis among TB smear positive contact whose registered in Port Sudan chest hospital TBMU center during third and fourth quarters; June to December 2023. Methodology: This is a descriptive cross sectional community base study, Port Sudan, eastern Sudan, from June 2023 to December 2023. Result: The study shows that prevalence of tuberculosis among smear positive contact individual is 4.6%s. And it shows other associated risk factors has a role in spread of the disease. Conclusion: The prevalence of tuberculosis among smear positive contact individuals in Port Sudan is low comparing to literature and other studies due to strong tuberculosis program and stigma also play a role in this reduction. Tuberculosis spread more among female and elder contact as the spend more time in the home. And immunosuppression, poor ventilation and crowded household play an essential role in spread of tuberculosis.

Anti-aminoacyl tRNA synthetase antibodies showing the discrepancy between enzyme-linked immunosorbent assay and RNA-immunoprecipitation

Anti-aminoacyl-tRNA synthetase (ARS) antibodies are myositis-specific antibodies associated with anti-synthetase syndrome (ASSD). Some patients are positive for anti-ARS antibodies on enzyme-linked immunosorbent assay (ELISA) but negative on RNA-immunoprecipitation (RNA-IP) (the gold standard method). Whether these patients should be considered truly positive for anti-ARS antibodies remains unclear. Therefore, we investigated the clinical characteristics of these patients and verified the authenticity of their anti-ARS positivity. Patients who were positive for anti-ARS antibodies on ELISA were divided into the non-discrepant (positive on RNA-IP, n = 52) and discrepant (negative on RNA-IP, n = 8) groups. Patient clinical characteristics were compared between the groups. For each positive individual, the authenticity of anti-ARS antibody positivity on ELISA was cross-examined using protein-IP and western blotting. All patients in the discrepant group had lung involvement, including five (63%) with interstitial lung disease. The overall survival time was significantly lower in the discrepant group than in the non-discrepant group (p < 0.05). Validation tests confirmed the presence of anti-ARS antibodies in the sera of the discrepant group but indicated different reactivity from typical anti-ARS antibodies. In conclusion, some anti-ARS antibodies are detected by ELISA but not RNA-IP. Such anti-ARS antibody discrepancies need further elucidation to attain validation of the diagnostic process in ASSD.

Fatal leptospirosis in endangered Barbary macaques (Macaca sylvanus) kept in captivity: Assessing the role of sympatric rodents

Between December 2020 and January 2021, an outbreak of acute mortality in endangered Barbary macaques (Macaca sylvanus) kept in captivity was detected in a zoo in Spain. The main findings observed in the two fatally affected animals at post-mortem evaluation were jaundice, renal tubular necrosis and interstitial nephritis. Leptospira spp. infection was confirmed by real time PCR (qPCR) in different tissues in both individuals. Analyses of secY gene from a positive individual showed 100% homology with a previously published sequence corresponding to Leptospira interrogans serovar Copenhageni. Free-living sympatric brown rats (Rattus norvegicus) from the affected zoo were also analyzed, and showed a prevalence and seroprevalence of Leptospira spp. of 18.2% (4/22; 95% CI: 2.1–34.3) and 41.9% (26/62; 95% CI: 29.7–54.2), respectively. We detected seropositive sera to five different serovars of Leptospira spp. (Copenhageni, Grippotyphosa, Pomona, Canicola and Hardjo) in the rodent population, with L. Copenhageni being the predominant one. This study describes for first time an outbreak of fatal leptospirosis in captive non-human primates in Europe. Our results show that Barbary macaques, an endangered species, are highly susceptible to Leptospira spp. infection, with sympatric wild rodents being the most likely reservoir animals involved in transmission in this outbreak. Our results suggest that rodent control could be an effective measure for minimizing exposure to Leptospira spp. in zoological collections. Given the potential implications for conservation, animal and public health, non-human primates and rodents should be included in surveillance programs for Leptospira spp. in zoos.

Disseminating the research findings from the adolescents and adults living with Perinatal HIV (AALPHI) study: an approach from young people living with HIV

BackgroundThe Adolescents and Adults Living with Perinatal HIV (AALPHI) study is one of only three cohort studies worldwide evaluating the impact of HIV on young people living with perinatal HIV (PLHIV) relative to a comparable group of HIV negative young people in close relationship with an HIV positive individual, for example, their mother, sibling or partner. This project aimed to engage young people with the AALPHI study findings, help them take ownership, and decide how they would disseminate the key messages to both study participants and to the wider community.MethodsIn brief, 318 PLHIV and 100 HIV negative adolescents participated in AALPHI, where they each were interviewed twice, around two years apart. They were asked a wide range of psychosocial and risk behaviour questions and their cognitive function was assessed. We invited three AALPHI participants and seven members of the Youth Trials Board at the Children’s HIV Association (CHIVA) to attend up to four workshops. They were provided with the key AALPHI research findings and asked to develop them into a format that was accessible and understandable for young people. Some who had not participated before formed a group in the fourth dissemination workshop that confirmed the most important concepts and results.ResultsThe young people decided to develop a film and a leaflet about the AALPHI findings and co-produced them with a film maker and graphic designer. Challenges included working with the film maker and the venue for the first three dissemination workshops was an office space which was not ideal.ConclusionEngaging young people in the dissemination of the AALPHI findings ensured the results were communicated in a way that was more likely to be relevant, accessible and useful to those affected by the study. This project demonstrates how young people in potentially stigmatised areas of care, such as HIV, can be involved in research dissemination.

Coinfection of HCV among HIV-infected patients: Across-sectional study in rivers State, Nigeria

Background: Hepatitis C virus (HCV) has emerged as the cause of the second major epidemic of viral infection after human immunodeficiency virus (HIV) within the past two decades. HCV is the cause of more than three-quarters of liver-relate deaths in HIV-seropositive individuals and it is remarkable that today approximately one-quarter of HIV-infected individuals Aim: this study aimed at determining the prevalence of coinfection patterns of HCV among HIV infected individual in Rivers State, Nigeria. Materials and methods: A retrospective survey conducted on 350 HIV infected individual attending ART clinic at Rivers State University Teaching Hospital, Port Harcourt, Nigeria. Sociodemographic data were collected based on interviewer-based questionnaire, and clinical history was obtained from participants' medical records. Antibody analyses for HCV were done using ELISA method. Results: The prevalence of hepatitis C virus coinfection among HIV positive individual was 6(4.0%), The prevalence of HCV and HIV positive individual with regards to age was high within the age of 21 -40 5(2.4%). Prevalence based on gender was females 4(1.1%) and males 2(1.4%), prevalence of HIV/HCV co-infection with respect to marital status was high among the single 6(4.9%), prevalence of HIV/HCV co-infection with respect educational status was high with tertiary 3(3.5%) than the secondary 3(1.6%). The prevalence among the different occupational groups, business had the highest co-infection rate (1.1%) followed closely by Working class (0.8%). Higher HIV/HCV co-infection was observed among those with CD4 cell count 350-499 cells/μl (4.6%). Conclusion: However, the low burden of this hepatotropic virus coinfection calls for continued need to screen for HCV among individual infected with HIV before the start of ART.

Leptospira spp. detection in bats from the Peninsula of Yucatán, México

The records of Leptospira spp. in bats from México are scarce. It is known that several species of bats are hosts of pathogenic Leptospira spp.; therefore, they participate in the epidemiological cycle and can generate transmission scenarios to people and animals. The aim was to detect the DNA of Leptospira spp. in bats captured in four sites from the Yucatán Peninsula, México. A kidney fragment was collected from the bats and used to extract genomic DNA. Using a PCR, the DNA of Leptospira spp. was detected. Fifty–four bats of the species Desmodus rotundus, Mimon cozumelae, Pteronotus mesoamericanus, Pteronotus fulvus, Nyctinomops laticaudatus, Peropteryx macrotis, Molossus nigricans, Molossus aztecus, Noctilio leporinus, Saccopteryx bilineata and Mormoops megalophylla were studied. The PCR yielded a total frequency of Leptospira spp. of 44.4% (24/54, 95% CI 36.2–71.7%). Species with at least one positive individual were D. rotundus, M. cozumelae, P. mesoamericanus, N. laticaudatus, P. macrotis, M. nigricans, N. leporinus, M. aztecus, and S. bilineata. A high frequency of Leptospira spp. was found in different species of bats belonging to several trophic guilds. The presence of Leptospira spp. in bats is relevant for Public and Animal Health because the evidence indicates that they can generate zoonotic transmission cycles.

Diagnosis of Pneumocystis Jirovecii in an HIV positive individual using traditional techniques and molecular biology methods.

Pneumocystis jirovecii (PJ) è un microrganismo ubiquitario (micete) trasmesso per via aerea. &lt;br /&gt;Persone immunocompromesse (individui HIV-positivi con conta linfocitaria CD4+ T &lt;200 cell/micoL, disordini linfoproliferativi, trapianto di cellule staminali, malattia di Cushing) sono a rischio di sviluppare polmonite da PJ. Gli autori presentano un caso di polmonite da PJ, la cui diagnosi è stata confermata sia da lavaggio broncoalveolare (BAL) sia dal plasma del paziente con identificazione microscopica.&lt;br /&gt;Il nostro paziente era un uomo caucasico di 35 anni, ricoverato nel reparto di malattie infettive dell’ospedale Sa Luca di Lucca, dal momento che presentava sintomi caratterizzati da febbre, dispnea, e immagine radiologica (tomografia computerizzata torace) compatibile con polmonite interstiziale bilaterale. L’uomo è stato sottoposto a BAL e prelievo di sangue periferico. I campioni sono stati analizzati con tecniche di biologia molecolare per il rilevamento e la quantificazione del DNA di PJ. Il campione BAL è anche stato analizzato per la ricerca microscopica di PJ. I campioni analizzati sono risultati positivi per PJ, sia in RT-PCR che in microscopia ottica.

SARS-CoV-2 transmission patterns in educational settings during the Alpha wave in Reggio-Emilia, Italy

Different monitoring and control policies have been implemented in schools to minimize the spread of SARS-CoV-2. Transmission in schools has been hard to quantify due to the large proportion of asymptomatic carriers in young individuals. We applied a Bayesian approach to reconstruct the transmission chains between 284 SARS-CoV-2 infections ascertained during 87 school outbreak investigations conducted between March and April 2021 in Italy. Under the policy of reactive quarantines, we found that 42.5% (95%CrI: 29.5–54.3%) of infections among school attendees were caused by school contacts. The mean number of secondary cases infected at school by a positive individual during in-person education was estimated to be 0.33 (95%CrI: 0.23–0.43), with marked heterogeneity across individuals. Specifically, we estimated that only 26.0% (95%CrI: 17.6–34.1%) of students and school personnel who tested positive during in-person education caused at least one secondary infection at school. Positive individuals who attended school for at least 6 days before being isolated or quarantined infected on average 0.49 (95%CrI: 0.14–0.83) secondary cases. Our findings provide quantitative insights on the contribution of school transmission to the spread of SARS-CoV-2 in young individuals. Identifying positive cases within 5 days after exposure to their infector could reduce onward transmission at school by at least 30%.

Assessment of Knowledge on HIV Screening Among Students in Girls' Secondary School Abayi, Aba, Abia State, Nigeria

Background: Voluntary counseling and testing is a vital element of Human Immunodeficiency Virus (HIV) prevention and care strategies worldwide. It is a test carried out to determine the HIV status of a person. HIV screening enables early detection and initiation of treatment which improves the quality, and life expectancy of a HIV positive individual. Adolescents are among the vulnerable groups with an increased risk of exposure to HIV/AIDS and need to embrace HIV/AIDS testing and counseling. Objective: To assess the knowledge on HIV screening amongst adolescents in Girls’ Secondary School Abayi with a view to enlighten them on the importance of HIV screening. Materials and Methods: It was a descriptive cross-sectional study and semi-structured questionnaire was used for data collection. Students within the ages of 10-19 years were selected by systematic sampling methods and 424 students were presented using tables. Association was tested at p-value of 0.05%. Results: There was a non-response rate of 20 (4.7%). Two-hundred and thirty-four (57.9%) of the students had good knowledge of HIV/AIDS screening and 282 (69.8%) knew that HIV screening is a test to determine individual HIV status. Uptake of HIV screening was 57(14.1%) and 178 (44.1%) students believed that the reason for poor HIV screening was lack of proper awareness. Benefits of HIV screening included helping to start early treatment as accepted by 191 (47.3%) students and 332 (82.2%) respondents agreed that the test provided opportunity for proper advice on knowledge of HIV. Association of class of the respondents and knowledge HCT was found to be statistically significant with p-values of 0.006. Conclusion: There was a good knowledge of HIV screening among the students. The major reason for poor screening uptake were lack of awareness on HIV screening and inadequate provision of screening opportunities. HIV screening awareness was recommended.

An Unconventional Presentation of Mucormycosis in a 10-Year-Old Child: A Case Report

Since the Coronavirus Disease (COVID-19) pandemic, there have been several unusual presentations of mucormycosis in India, especially amongst immune-competent adults. COVID-19 infection has been found to have profound effects on the patient’s immunity and some patients, though asymptomatic for COVID-19, can be infected by mucormycosis and develops dangerous complications. Skin involvement of the orbital, zygomatic and maxillary areas is a common occurrence in extensive cases of rhinoorbital mucormycosis, however, isolated involvement of the alar skin is an extremely rare occurrence in such patients. Paediatric cutaneous mucormycosis is by itself a rare entity, seen majorly in children with history of allogeneic hematopoietic stem cell transplantations, chemotherapeutic treatment, or patients with human immunodeficiency virus infections, herpes and other lifethreatening viral infections. Patients receiving long-term steroid therapy are also predisposed to invasive fungal infections. This case was about a 10-year-old boy presented with a black crusted lesion over the nose to the otolaryngology outpatient department. The patient had history of contact with a COVID-19 positive individual. Examination revealed a necrotic patch over the palate and Non Contrast CT Scan of (NCCT) the paranasal sinuses showed pansinusitis. A KOH mount showed fungal elements and the patient underwent emergency debridement of nasal skin with endoscopic sinus and palatal debridement. Injectable liposomal Amphotericin-B was started. Over a period of one month, the patient showed significant clinical improvement. Though rare, sinonasal mucormycosis can present in the form of a cutaneous lesion which is an unconventional symptom. A general awareness amongst healthcare professionals, with a multidisciplinary approach, timely diagnosis and specialist intervention can improve outcomes in this sinister disease.

Utilizing student-led contact tracing initiative to alleviate COVID-19 disease burden in central Pennsylvania

Contact tracing elicits probable contacts from COVID-19 cases. Our student-led contact tracing initiative promoted isolation of both confirmed and probable cases and quarantine of contacts to reduce disease in Central Pennsylvania. Close contacts of COVID-19 cases were contacted by tracers, advised to quarantine, and monitored for 14 days for symptoms. Symptomatic contacts were classified as probable cases and advised to isolate. Data was collected from March 24, 2020 to May 26, 2020. Poisson regression and linear regression were utilized to examine the relationships between case and number of contacts and proportion of symptomatic contacts. Study sample comprised of 346 confirmed and 157 probable cases. Our results indicate a significant difference in percent of household contacts who became symptomatic between confirmed and probable cases (22% vs. 3%; adjusted P<.01). Similarly, probable cases had significantly fewer non-household contacts compared to confirmed cases (0.87 vs. 0.55; adjusted P<.01). Timely notification of exposure to a COVID-19 positive individual by student contact tracers allowed for probable cases to quarantine early in the disease process. Our data suggests that early quarantine and/or isolation may have directly contributed to probable cases having fewer non-household contacts and a smaller proportion of symptomatic household-contacts compared to confirmed cases.

Performance and Cost-effectiveness of Pooling COVID-19 Samples Using Real time Polymerase Chain Reaction Test

Rapid detection of Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) by real-time polymerase chain reaction (RT-PCR) is the most reliable method used worldwide. Although the incidence of the disease has increased globally, the limited availability of PCR kits has become the major bottleneck for the diagnosis of COVID positive patients. Random samples were pooled for two months in group of two-five and tested for SARS-CoV-2. If the pool was negative, all individuals in the pool were reported negative. If the pool was positive, then the individual samples were retested to identify the positive individual. The mean cycle threshold (Ct) value of pooled samples was not significantly different with that of individual samples for N, ORF-1ab and E genes. Also, pooling saved more than 60% of reagents, time and effort, workforce and cost. In this study, the positivity rate was around 5% and saving of reagent, cost, time and manpower was more than 60%.

Defining Key Performance Indicators for the California COVID-19 Exposure Notification System (CA Notify).

Toward common methods for system monitoring and evaluation, we proposed a key performance indicator framework and discussed lessons learned while implementing a statewide exposure notification (EN) system in California during the COVID-19 epidemic. California deployed the Google Apple Exposure Notification framework, branded CA Notify, on December 10, 2020, to supplement traditional COVID-19 contact tracing programs. For system evaluation, we defined 6 key performance indicators: adoption, retention, sharing of unique codes, identification of potential contacts, behavior change, and impact. We aggregated and analyzed data from December 10, 2020, to July 1, 2021, in compliance with the CA Notify privacy policy. We estimated CA Notify adoption at nearly 11 million smartphone activations during the study period. Among 1 654 201 CA Notify users who received a positive test result for SARS-CoV-2, 446 634 (27%) shared their unique code, leading to ENs for other CA Notify users who were in close proximity to the SARS-CoV-2-positive individual. We identified at least 122 970 CA Notify users as contacts through this process. Contact identification occurred a median of 4 days after symptom onset or specimen collection date of the user who received a positive test result for SARS-CoV-2. Smartphone-based EN systems are promising new tools to supplement traditional contact tracing and public health interventions, particularly when efficient scaling is not feasible for other approaches. Methods to collect and interpret appropriate measures of system performance must be refined while maintaining trust and privacy.

Co-Infection Status of Enterovirus among Hepatitis (A, B, and C) Positive Individual Living within Abuja Internally Displaced Persons Camps

The Enterovirus (EV-71) co-infection among Hepatitis A, B and C virus has become a global co-mortality. This research determined enteroviruses (EV-71) co-infection profile among HAV, HBV and HCV positive individuals within internally displaced persons camps Abuja, Nigeria. A descriptive cross sectional research design was adopted where blood samples from 450 respondents were collected within the three camps and screened for the presence of Hepatitis A, B and C. Positive samples were further assayed for co-infection with Enterovirus-71 using Rapid Strip RT-PCR Amplification of 16sRNA for Enterovirus 71(EV71). The data were analyzed using the SPSS Version 22.1 Software. The results revealed that out of the 450 studied subjects 11 (2.4%) were HAV positive, 42 (9.3%) were HBV positive and 33 (7.3%) were HCV positive. Only 1 (0.2%) subject was found to be co-infected with HAV/EV-71. The prevalence of hepatitis among the studied subjects was found to differ significantly among males and females (P=0.001), among various age groups (P=0.001) and among various occupation (P=0.001). The study reports low rate of Enterovirus-71 among hepatitis (A, B, and C) positive individuals living within Abuja internally displaced persons camps. The study recommends routine screening of internally displaced individuals for the presence of hepatitis virus and EV-71 for early diagnosis and possible adoption of management and control measures that may include vaccination of infected individuals.

Cost-analysis of COVID-19 sample collection, diagnosis, and contact tracing in low resource setting: The case of Addis Ababa, Ethiopia.

Ethiopia has been responding to the COVID-19 pandemic through a combination of interventions, including non-pharmaceutical interventions, quarantine, testing, isolation, contact tracing, and clinical management. Estimating the resources consumed for COVID-19 prevention and control could inform efficient decision-making for epidemic/pandemic-prone diseases in the future. This study aims to estimate the unit cost of COVID-19 sample collection, laboratory diagnosis, and contact tracing in Addis Ababa, Ethiopia. Primary and secondary data were collected to estimate the costs of COVID-19 sample collection, diagnosis, and contact tracing. A healthcare system perspective was used. We used a combination of micro-costing (bottom-up) and top-down approaches to estimate resources consumed and the unit costs of the interventions. We used available cost and outcome data between May and December 2020. The costs were classified into capital and recurrent inputs to estimate unit and total costs. We identified the cost drivers of the interventions. We reported the cost for the following outcome measures: (1) cost per sample collected, (2) cost per laboratory diagnosis, (3) cost per sample collected and laboratory diagnosis, (4) cost per contact traced, and (5) cost per COVID-19 positive test identified. We conducted one-way sensitivity analysis by varying the input parameters. All costs were reported in US dollars (USD). The unit cost per sample collected was USD 1.33. The unit cost of tracing a contact of an index case was USD 0.66. The unit cost of COVID-19 diagnosis, excluding the cost for sample collection was USD 3.91. The unit cost of sample collection per COVID-19 positive individual was USD 11.63. The unit cost for COVID-19 positive test through contact tracing was USD 54.00. The unit cost COVID-19 DNA PCR diagnosis for identifying COVID-19 positive individuals, excluding the sample collection and transport cost, was USD 37.70. The cost per COVID-19 positive case identified was USD 49.33 including both sample collection and laboratory diagnosis costs. Among the cost drivers, personnel cost (salary and food cost) takes the highest share for all interventions, ranging from 51-76% of the total cost. The costs of sample collection, diagnosis, and contact tracing for COVID-19 were high given the low per capita health expenditure in Ethiopia and other low-income settings. Since the personnel cost accounts for the highest cost, decision-makers should focus on minimizing this cost when faced with pandemic-prone diseases by strengthening the health system and using digital platforms. The findings of this study can help decision-makers prioritize and allocate resources for effective public health emergency response.

SARS-CoV-2 Distribution in Residential Housing Suggests Contact Deposition and Correlates with Rothia sp.

ABSTRACTMonitoring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on surfaces is emerging as an important tool for identifying past exposure to individuals shedding viral RNA. Our past work demonstrated that SARS-CoV-2 reverse transcription-quantitative PCR (RT-qPCR) signals from surfaces can identify when infected individuals have touched surfaces and when they have been present in hospital rooms or schools. However, the sensitivity and specificity of surface sampling as a method for detecting the presence of a SARS-CoV-2 positive individual, as well as guidance about where to sample, has not been established. To address these questions and to test whether our past observations linking SARS-CoV-2 abundance to Rothia sp. in hospitals also hold in a residential setting, we performed a detailed spatial sampling of three isolation housing units, assessing each sample for SARS-CoV-2 abundance by RT-qPCR, linking the results to 16S rRNA gene amplicon sequences (to assess the bacterial community at each location), and to the Cq value of the contemporaneous clinical test. Our results showed that the highest SARS-CoV-2 load in this setting is on touched surfaces, such as light switches and faucets, but a detectable signal was present in many untouched surfaces (e.g., floors) that may be more relevant in settings, such as schools where mask-wearing is enforced. As in past studies, the bacterial community predicts which samples are positive for SARS-CoV-2, with Rothia sp. showing a positive association.IMPORTANCE Surface sampling for detecting SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), is increasingly being used to locate infected individuals. We tested which indoor surfaces had high versus low viral loads by collecting 381 samples from three residential units where infected individuals resided, and interpreted the results in terms of whether SARS-CoV-2 was likely transmitted directly (e.g., touching a light switch) or indirectly (e.g., by droplets or aerosols settling). We found the highest loads where the subject touched the surface directly, although enough virus was detected on indirectly contacted surfaces to make such locations useful for sampling (e.g., in schools, where students did not touch the light switches and also wore masks such that they had no opportunity to touch their face and then the object). We also documented links between the bacteria present in a sample and the SARS-CoV-2 virus, consistent with earlier studies.

MO194: A Rare Case of Secondary Haemolytic Uremic Syndrome after ANTI-SARS-COV-2 Vaccination

Abstract BACKGROUND AND AIMS Haemolytic uremic syndrome (HUS) is a rare disease characterized by macroangiopathic haemolytic anaemia, thrombocytopaenia and severe AKI, belonging to the thrombotic microangiopathies (TMAs). It is divided into typical and atypical HUS: the first one occurs most frequently in children within the first 5 years of life and it is associated with Shiga-like toxin producing Escherichiacoli infection; the second one (aHUS) is less common (10%) and it is due to complement abnormalities with coexisting disease or trigger such as autoimmunity, transplantation, cancer, infection, certain cytotoxic drugs or pregnancy. There is an increasing interest in SARS-CoV-2 infection as new trigger for complement activation. Nine cases of aHUS were recently associated with COVID-19, most of them occurring within 1 month from the infection. Available data suggest that SARS-CoV-2 is a potential trigger for aHUS: it can induce an over inflammatory state and to activate coagulation and complement pathway. Likewise, mRNA-based vaccines against COVID-19 inducing the expression of SARS-CoV-2 spike protein to stimulate immune recognition and antibody response could be a suitable trigger for HUS. METHOD We report the case of a 17-year-old woman, who presented at our emergency department with fever, dyspnoea, acute kidney injury AKI III with anuria, hypertension, severe anaemia, no diarrhoea, severe thrombocytopaenia and myocarditis, about 2 weeks after the first administration of SARS-CoV-2 vaccine (Comirnaty) and recent exposition to SARS-CoV-2 positive individual. SARS-CoV-2 nasal PCR swab was negative (as well as successive ones) and she was immediately admitted to paediatric intensive care unit and treated with transfusions and haemodialysis. Laboratory exams suggested a thrombotic microangiopathy with normal ADAMTS-13 activity and no E. coli infection. She underwent a renal biopsy that confirmed our hypothesis of aHUS: wrinkled capillaries, subendothelial expansion, mesangiolysis and rare thrombi in capillaries lumen. Arterioles had intimal proliferation with mucoid oedema who gave rise to onionskin like lesion that obliterates lumens. One glomerulus showed extracapillary proliferation (crescent), and there was interstitial lymphomonocytic inflammatory infiltration in the nearby. Also signs of acute tubular injury and atrophy were reported. Positive stain to fibrinogen in the arterioles at immunohistology was noted. She immediately performed genetic exams for aHUS-related complement mutations and she started immunosuppression with corticosteroids and eculizumab infusions. After 2 months of eculizumab, she was still oliguric, requiring renal replacement therapy. Genetic analysis showed no mutations. Therefore, she was examined for other genetic causes of thrombotic microangiopathies. RESULTS Finally, came to light that she had high levels of homocysteine, and she was diagnosed with secondary HUS associated with cobalamin C deficiency, which manifests with methylmalonic aciduria and homocystinuria due to a recessive mutation in the MMACHC gene, causing a cobalamin C type deficiency, which is the common functional variant of vitamin B12. After metabolic therapy with hydroxocobalamin, she gradually recovered diuresis and partially renal function without need for replacement therapy. CONCLUSION Reports from immunization programs show as myocarditis and thrombotic thrombocytopaenia are considered among main serious complications caused by COVID-19 vaccines, representing 12.6 cases per million doses and 0.73 cases per 100 000, respectively. This interesting case probably supports data about the role of mRNA-based anti-SARS-CoV-2 vaccines like a precipitant factor for TMAs. Moreover, our patient turned out to be an extremely rare case of HUS secondary to cobalamin C deficiency, that is generally diagnosed in early infancy and show typically neurological symptoms (absent in our case). Probably, the mRNA-based vaccine acted like ‘a second hit’, but existing predisposition should always be investigated including also the less frequent forms.

Speech as a Biomarker for COVID-19 Detection Using Machine Learning.

The use of speech as a biomedical signal for diagnosing COVID-19 is investigated using statistical analysis of speech spectral features and classification algorithms based on machine learning. It is established that spectral features of speech, obtained by computing the short-time Fourier Transform (STFT), get altered in a statistical sense as a result of physiological changes. These spectral features are then used as input features to machine learning-based classification algorithms to classify them as coming from a COVID-19 positive individual or not. Speech samples from healthy as well as “asymptomatic” COVID-19 positive individuals have been used in this study. It is shown that the RMS error of statistical distribution fitting is higher in the case of speech samples of COVID-19 positive speech samples as compared to the speech samples of healthy individuals. Five state-of-the-art machine learning classification algorithms have also been analyzed, and the performance evaluation metrics of these algorithms are also presented. The tuning of machine learning model parameters is done so as to minimize the misclassification of COVID-19 positive individuals as being COVID-19 negative since the cost associated with this misclassification is higher than the opposite misclassification. The best performance in terms of the “recall” metric is observed for the Decision Forest algorithm which gives a recall value of 0.7892.