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    6. Infectious Disease
    (2026-12-31)
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    6. Infectious Disease
    (2026-12-31)
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    A Bayesian modelling framework with model comparison for epidemics with super-spreading
    (2025-12) Craddock, Hannah; Spencer, Simon E.F.; Didelot, Xavier
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    A Case of Spinal Epidural Abscess and Paraplegia After Group A Streptococcal Pharyngitis
    (2026-7-4) McKinley Blake J.; Seby Rob M.; Chase Robert C.; Gavrancic Tatjana; Collado Jeremy; Rueda Prada Libardo
    Background: Spinal epidural abscesses (SEA) are rare, occurring 2.5–3 times per 10,000 hospital admissions. While streptococcus species comprise 7% of reported SEAs, Group A Streptococcus (GAS) has been described only once in the medical literature to our knowledge. Case presentation: We present a case of GAS pharyngitis with subsequent paraplegia from a GAS SEA. A 33-year-old female presented to the emergency department (ED) and was initially diagnosed with GAS pharyngitis and a suspected strained lower back. Following treatment with amoxicillin, she returned with worsened back pain, radiculopathy, and leukocytosis, for which she was treated with cyclobenzaprine. On her third presentation, she had new bilateral lower extremity weakness with decreased sensation, bilateral ankle clonus, and hyperreflexia. MRI of the thoracic and lumbar spine revealed a multiloculated SEA at T5-T10 requiring laminectomy and abscess evacuation. Intraoperative cultures grew Streptococcus pyogenes. Despite surgery, medical management, and physical therapy, she remained paraplegic. Conclusions: To our knowledge, this is the first report of SEA preceded by GAS pharyngitis. This case exposes the critical association between a recent infection, progression of back pain, eventual neurologic symptoms, and inflammatory markers that should trigger concern for SEA and early evaluation with MRI.
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    A challenging case of refractory infection following fish fin injury: Successful treatment through combined therapy
    (2025-11) Chen, Yanqing; Mo, Shifu; Li, Jianjian; Zhong, Huiting; Chao, Chikit; Liu, Ting; Ma, Han
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    A cluster randomized trial of routine HIV-1 viral load monitoring in Zambia: study design, implementation, and baseline cohort characteristics.
    (2010-Mar-12) Koethe, John R.; Westfall, Andrew O.; Luhanga, Dora K.; Clark, Gina M.; Goldman, Jason D.; Mulenga, Priscilla L.; Cantrell, Ronald A.; Chi, Benjamin H.; Zulu, Isaac; Saag, Michael S.; Stringer, Jeffrey S.
    BACKGROUND: The benefit of routine HIV-1 viral load (VL) monitoring of patients on antiretroviral therapy (ART) in resource-constrained settings is uncertain because of the high costs associated with the test and the limited treatment options. We designed a cluster randomized controlled trial to compare the use of routine VL testing at ART-initiation and at 3, 6, 12, and 18 months, versus our local standard of care (which uses immunological and clinical criteria to diagnose treatment failure, with discretionary VL testing when the two do not agree). METHODOLOGY: Dedicated study personnel were integrated into public-sector ART clinics. We collected participant information in a dedicated research database. Twelve ART clinics in Lusaka, Zambia constituted the units of randomization. Study clinics were stratified into pairs according to matching criteria (historical mortality rate, size, and duration of operation) to limit the effect of clustering, and independently randomized to the intervention and control arms. The study was powered to detect a 36% reduction in mortality at 18 months. PRINCIPAL FINDINGS: From December 2006 to May 2008, we completed enrollment of 1973 participants. Measured baseline characteristics did not differ significantly between the study arms. Enrollment was staggered by clinic pair and truncated at two matched sites. CONCLUSIONS: A large clinical trial of routing VL monitoring was successfully implemented in a dynamic and rapidly growing national ART program. Close collaboration with local health authorities and adequate reserve staff were critical to success. Randomized controlled trials such as this will likely prove valuable in determining long-term outcomes in resource-constrained settings. TRIAL REGISTRATION: Clinicaltrials.gov NCT00929604.
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    A Co-Designed Framework for a Self-Reporting Surveillance Tool for Infectious Disease Outbreaks (Preprint)
    Peters Ezinne
    BACKGROUND

    Infectious diseases are a continuing challenge to global health, and supporting surveillance is critical. Digital self-reporting tools can support infectious disease surveillance, but their effectiveness depends on credibility, usefulness, and cultural appropriateness.

    OBJECTIVE

    To co-design a context specific framework for a self-reporting surveillance tool for infectious disease outbreaks in Nigeria

    METHODS

    We conducted a qualitative co-design study involving stakeholders involved in infectious disease surveillance and response in Abuja, Nigeria. During a two-day workshop, stakeholders, which included individuals engaged in surveillance, community advocacy, digital technology, and policy in Nigeria, worked in groups undertaking activities including brainstorming, card sorting, scenario walkthroughs and then refinement of the framework. Data sources included audio records of the workshops, and co-design artefacts. We used reflexive thematic analysis to synthesize outputs

    RESULTS

    A framework was developed including 10 components of a self-reporting surveillance tool: the landing page, menu/navigation, biodata, location, epidemiological information, medical information, comorbidities, feedback, frequently asked questions and other features (including multimodal access and offline options). Cross-cutting priorities included clarity, trust, multilingual access, inclusiveness, linkage to the health system, equity, and usability in low-connectivity settings.

    CONCLUSIONS

    Our co-designed framework offers an empirical basis for designing a self-reporting surveillance tool to support infectious disease surveillance in Nigeria. We designed it to be culturally sensitive, trustworthy, and easy to use across languages, with multiple ways to access it, including Unstructured Supplementary Service Data (USSD), offline use, and SMS, so it continues to work even in settings with poor internet connectivity.

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    A color-coded tape for uterine height measurement: a tool to identify preterm pregnancies in low resource settings.
    (2015) Althabe, Fernando; Berrueta, Mabel; Hemingway-Foday, Jennifer; Mazzoni, Agustina; Bonorino, Carolina A.; Gowdak, Andrea; Gibbons, Luz; Bellad, M. B.; Metgud, M. C.; Goudar, Shivaprasad ; Kodkany, Bhalchandra S.; Derman, Richard J.; Saleem, Sarah; Iqbal, Samina; Ala, Syed H.; Goldenberg, Robert L.; Chomba, Elwyn; Manasyan, Albert; Chiwila, Melody; Imenda, Edna; Mbewe, Florence; Tshefu, Antoinette; Lokomba, Victor; Bose, Carl L.; Moore, Janet; Meleth, Sreelatha ; McClure, Elizabeth M.; Koso-Thomas, Marion; Buekens, Pierre; Belizán, Jose M.
    INTRODUCTION: Neonatal mortality associated with preterm birth can be reduced with antenatal corticosteroids (ACS), yet <10% of eligible pregnant women in low-middle income countries. The inability to accurately determine gestational age (GA) leads to under-identification of high-risk women who could receive ACS or other interventions. To facilitate better identification in low-resource settings, we developed a color-coded tape for uterine height (UH) measurement and estimated its accuracy identifying preterm pregnancies. METHODS: We designed a series of colored-coded tapes with segments corresponding to UH measurements for 20-23.6 weeks, 24.0-35.6 weeks, and >36.0 weeks GA. In phase 1, UH measurements were collected prospectively in the Democratic Republic of Congo, India and Pakistan, using distinct tapes to address variation across regions and ethnicities. In phase 2, we tested accuracy in 250 pregnant women with known GA from early ultrasound enrolled at prenatal clinics in Argentina, India, Pakistan and Zambia. Providers masked to the ultrasound GA measured UH. Receiver operating characteristics (ROC) analysis was conducted. RESULTS: 1,029 pregnant women were enrolled. In all countries the tapes were most effective identifying pregnancies between 20.0-35.6 weeks, compared to the other GAs. The ROC areas under the curves and 95% confidence intervals were: Argentina 0.69 (0.63, 0.74); Zambia 0.72 (0.66, 0.78), India 0.84 (0.80, 0.89), and Pakistan 0.83 (0.78, 0.87). The sensitivity and specificity (and 95% confidence intervals) for identifying pregnancies between 20.0-35.6 weeks, respectively, were: Argentina 87% (82%-92%) and 51% (42%-61%); Zambia 91% (86%-95%) and 50% (40%-60%); India 78% (71%-85%) and 89% (83%-94%); Pakistan 63% (55%-70%) and 94% (89%-99%). CONCLUSIONS: We observed moderate-good accuracy identifying pregnancies ≤ 35.6 weeks gestation, with potential usefulness at the community level in low-middle income countries to facilitate the preterm identification and interventions to reduce preterm neonatal mortality. Further research is needed to validate these findings on a population basis.
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    A controlled study to assess the effects of a Fast Track (FT) service delivery model among stable HIV patients in Lusaka Zambia.
    (2022) Bolton-Moore, Carolyn; Pry, Jake M.; Mukumbwa-Mwenechanya, Mpande; Eshun-Wilson, Ingrid; Topp, Stephanie; Mwamba, Chanda; Roy, Monika; Sohn, Hojoon; Dowdy, David W.; Padian, Nancy; Holmes, Charles B.; Geng, Elvin H.; Sikazwe, Izukanji
    Fast Track models-in which patients coming to facility to pick up medications minimize waiting times through foregoing clinical review and collecting pre-packaged medications-present a potential strategy to reduce the burden of treatment. We examine effects of a Fast Track model (FT) in a real-world clinical HIV treatment program on retention to care comparing two clinics initiating FT care to five similar (in size and health care level), standard of care clinics in Zambia. Within each clinic, we selected a systematic sample of patients meeting FT eligibility to follow prospectively for retention using both electronic medical records as well as targeted chart review. We used a variety of methods including Kaplan Meier (KM) stratified by FT, to compare time to first late pick up, exploring late thresholds at >7, >14 and >28 days, Cox proportional hazards to describe associations between FT and late pick up, and linear mixed effects regression to assess the association of FT with medication possession ratio. A total of 905 participants were enrolled with a median age of 40 years (interquartile range [IQR]: 34-46 years), 67.1% were female, median CD4 count was 499 cells/mm3 (IQR: 354-691), and median time on ART was 5 years (IQR: 3-7). During the one-year follow-up period FT participants had a significantly reduced cumulative incidence of being >7 days late for ART pick-up (0.36, 95% confidence interval [CI]: 0.31-0.41) compared to control participants (0.66; 95% CI: 0.57-0.65). This trend held for >28 days late for ART pick-up appointments, at 23% (95% CI: 18%-28%) among intervention participants and 54% (95% CI: 47%-61%) among control participants. FT models significantly improved timely ART pick up among study participants. The apparent synergistic relationship between refill time and other elements of the FT suggest that FT may enhance the effects of extending visit spacing/multi-month scripting alone. ClinicalTrials.gov Identifier: NCT02776254 https://clinicaltrials.gov/ct2/show/NCT02776254.
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    A Cross-Sectional Study on Socio-Ecological and Socio-Anthropological Determinants of COVID-19 in Lusaka Province of Zambia
    (2022-9-28) Fonchin, Alyce F.; Mumba, Chisoni; Basikolo, Linda; Kallu, Simegnew A.; Kainga, Henson; Mwiinde, Jezreel; Benhard, Vistorina; Muma, John B.; Munyeme, Musso
    The COVID-19 disease constitutes a pandemic that has created an international public health emergency. Besides the significant health challenges, the impact of the COVID-19 disease has been the restriction of movements that have heavily affected the global economy. The first case of COVID-19 in Zambia was identified on March 18th, 2020. By the end of November 2020, the number of districts reporting COVID-19 infections had increased from 68 to 96, with reports of the highest transmission in the capital city, Lusaka, the Copperbelt, and Ndola districts. As COVID-19 spread across the nation of Zambia, several factors are responsible for the spread of the virus. Despite the extensive collection of research done on determinants of COVID-19 disease, the spatial distribution of the disease along socio-demographical and socio-ecological domains remains speculative and infectious diseases have been less looked into in the areas of anthropological dynamics. This study used a cross-sectional design to investigate the ecological and anthropological determinants of COVID-19 disease in four compounds in the Lusaka district of Zambia. A guided questionnaire was used to collect data from 301 participants. A descriptive analysis of all independent variables was done. Analysis for associations of dependent and independent variables and multivariate analysis of the independent variables significant at the bi-variate level was conducted to investigate the association between the dependent variable (Knowledge of anyone infected with COVID-19 virus) and the independent variables. The bi-variate analysis results showed that 14 independent variables with odds ratios greater than one were significantly associated with the spread of COVID-19. Two variables were found to be highly significant in the multivariable logistic regression analysis model. These included beliefs about COVID-19 (odds = 3.0; p = 0.003; CI 1.2-3.3), and participants area of residence (odds = 2.6; p = 0.003; CI = 1.2-5.5). Other significant multivariate variables were ecological variable; climate and anthropological variables; hand hygienic practices. The current research provides further insight into the potential role ecology and anthropology contribute to the spread of communicable diseases. The study recommends awareness of the population to enhance preparedness and response to reduce the spread of COVID-19.
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    A Deterministic Risk Assessment of the Human Exposure to Cadmium, Lead and Chromium Through the Consumption of Well and Bottled Water in Lusaka District, Zambia
    (2023-2-28) Banda, Mkuzi; Muma, John B.; Bumbangi, Flavien N.; M'kandawire, Ethel; Mukuma, Mercy; Munyeme, Musso; Musawa, Grace; Ndaki, Enock M; Benhard, Vistorina; Mumba, Chisoni
    The United Nations Sustainable Development Goal number six is to ‘Ensure availability and sustainable management of water and sanitation for all, which is an essential component for human survival. Access to safe drinking water is essential for health, a basic human right and a component of effective policy for health protection. Safe drinking water implies that the water does not represent any significant risk to health over a lifetime of consumption, including different sensitivities that may occur between life stages. However, water is prone to contamination with heavy metals through natural and anthropogenic sources, making it unsuitable for human consumption due to the cumulative potential risks associated with the presence of heavy metals. This study was conducted to assess the non-carcinogenic and carcinogenic risk of human exposure to cadmium, lead and chromium through the consumption of well and bottled water in Lusaka district of Zambia. Secondary data was used to determine the mean concentrations of heavy metals in well and bottled water in Lusaka district as well as to calculate the hazard index (non-carcinogenic risk) and cancer risk for the metals under study. The results revealed that a hazard index for cadmium, lead and chromium in both well and bottled water was higher than 1, indicating adverse effects on human health over a lifetime of consumption. Similarly, the total cancer risk through exposure to cadmium and chromium in well and bottled water was 1.2 x 10-1 and 2.25 x 10-1, respectively, higher than the safe threshold limit set by the United States Environmental Protection Agency (USEPA) of 1 × 10−4. The study concludes that there is a possible non-carcinogenic risk of exposure to cadmium, lead and chromium through the consumption of well and bottled water in Lusaka district. Further, the study concludes that there is a possible carcinogenic risk of exposure to cadmium and chromium through the consumption of both well and bottled water. Owing to the proportion of both well and bottled water samples that exceeded the Zambia Bureau of Standards threshold limit, cadmium poses the greatest concern and requires intervention to reduce exposure. Therefore, it is recommended that heavy metal concentrations in drinking water should be periodically monitored to minimize health risks to consumers.
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