Shilpa Hakre

Understanding the level of exposure to Lassa virus (LASV) in at-risk communities allows for the administration of effective preventive interventions to mitigate epidemics of Lassa fever. We assessed the seroprevalence of LASV antibodies in rural and semiurban communities of two cosmopolitan cities in Nigeria with poorly understood Lassa epidemiology. A cross-sectional study was conducted in ten communities located in the Abuja Municipal Area Council (AMAC), Abuja, and Ikorodu Local Government Area (LGA), Lagos, from February 2nd to July 5th, 2022. Serum samples collected from participants were analyzed for IgG and IgM antibodies using a ReLASV® Pan-Lassa NP IgG/IgM enzyme-linked immunosorbent assay (ELISA) kit. A questionnaire administered to participants collected self-reported sociodemographic and LASV exposure information. Seroprevalence of LASV IgG/IgM was estimated overall, and by study site. Univariate and multivariate log-binomial models estimated unadjusted and adjusted prevalence ratios (aPRs) and 95% confidence intervals (CI) for site-specific risk factors for LASV seropositivity. Grouped Least Absolute Shrinkage and Selection Operator (LASSO) was used for variable selection for multivariate analysis. A total of 628 participants with serum samples were included in the study. Most participants were female (434, 69%), married (459, 73%), and had a median age of 38 years (interquartile range 28–50). The overall seroprevalence was 27% (171/628), with a prevalence of 33% (126/376) in Abuja and 18% (45/252) in Lagos. Based on site-specific grouped LASSO selection, enrollment in the dry season (vs. wet; aPR, 95% CI: 1.73, 1.33–2.24), reported inconsistent washing of fruits and vegetables (aPR, 95% CI: 1.45, 1.10–1.92), and a positive malaria rapid test (aPR, 95% CI: 1.48, 1.09-2.00) were independently associated with LASV seropositivity in Abuja, whereas, only a self-reported history of rhinorrhea (PR, 95% CI: 2.21, 1.31–3.72) was independently associated with Lassa seropositivity in Lagos. The LASV seroprevalence was comparable to that in other areas in Nigeria. Our findings corroborate those from other studies on the importance of limiting human exposure to rodents and focusing on behavioral factors such as poor hygiene practices to reduce exposure to LASV.

Mycoplasma genitalium (MG) infection is a public health concern due to antimicrobial resistance (AMR). Data are limited on repeat MG infection and AMR among US Air Force service members with HIV. US Air Force service members seeking HIV care were screened for MG infection during the surveillance period (16 May 2016–16 March 2020). Baseline and repeat MG prevalence rates were estimated. An extended Cox proportional hazards regression model evaluated characteristics associated with repeat MG infection. MG-positive rectal samples were tested for macrolide or fluoroquinolone resistance. Among 299 male patients from a total of 308 patients followed during the surveillance period, baseline prevalence of MG infection was 19.7% (n = 59); among the 101 patients who screened positive for MG at any time during the surveillance period, repeat MG was 35% (n = 36). Characteristics independently associated with increased risk of repeat infection were sexually transmitted infection history vs none (adjusted hazard ratio [aHR], 2.33; 95% CI, 1.26–4.31), a sexually transmitted infection coinfection vs no positive test result in the medical records (aHR, 5.13; 95% CI, 2.78–9.49), and a new HIV diagnosis (<1 vs ≥1 year; aHR, 2.63; 95% CI, 1.45–3.73). AMR in MG-positive rectal specimens was 88% (43/49) indicating macrolide resistance, 18% (10/56) quinolone resistance, and 18% (10/56) both. Macrolide and fluoroquinolone resistance mutations were common. Testing for co-occurring MG infection and AMR mutations may be warranted in guiding treatment for sexually transmitted infections such as chlamydia or gonorrhea detected at HIV diagnosis.

Background: Mycoplasma genitalium (MG) infection is of public health concern due to antimicrobial resistance (AMR). Data are limited on repeat MG infection and AMR among United States Air Force (USAF) service members (SMs) living with human immunodeficiency virus (HIV). Methods: USAF SMs seeking HIV care were screened for MG infection during the surveillance period (May 16, 2016-March 16, 2020). Baseline and repeat MG prevalence were estimated. An extended Cox proportional hazards regression model evaluated characteristics associated with repeat MG infection. MG-positive rectal samples were tested for macrolide or fluoroquinolone resistance. Results: Among 299 male patients of a total 308 patients followed during the surveillance period, baseline prevalence of MG infection was 19.7% (59/299) and repeat MG was 35% (36/101) among patients who screened positive for MG at any time during the surveillance period. Characteristics independently associated with increased risk of repeat infection were reported prior sexually-transmitted infection (STI) history vs none (adjusted hazards ratio (aHR) 2.21, 95% confidence interval (CI) 1.13-4.35), presence of STI coinfection vs not indicated (aHR 5.13, 95% CI 2.78-9.49), new HIV diagnosis (<1 year vs 1 year or more, aHR 2.63, 95% CI 1.62-4.27). AMR in MG-positive rectal specimens was 88% (43/49) indicating macrolide resistance, 18% (10/56) with quinolone resistance, and 18% (10/56) with both macrolides and fluoroquinolone resistance. Conclusions: Macrolide and fluoroquinolone resistance mutations were common. Testing for co-occurring MG infection and AMR mutations may be warranted in guiding treatment for STIs such as chlamydia or gonorrhea detected at HIV diagnosis.

There have been nearly 1,600 new diagnoses of Human Immunodeficiency Virus (HIV) across the US Armed Forces between 2017 and 2022. While treatment has improved overall survival, self-perception of acquiring HIV may not align with actual risk of acquiring HIV, thus slowing diagnosis and treatment. We aim to evaluate self-perceived risk (SPR) versus calculated risk (CR) of HIV infection in US Air Force (USAF) members with incident HIV diagnosis. All USAF members with new HIV diagnosis evaluated at a specialty care military medical center between January 2015 and March 2020 with case report forms were included (n = 142). SPR was compared to CR using the Denver HIV Risk Score (DHRS). The study was approved by the Army Public Health Center’s Public Health Review Board (#14-311) and the Walter Reed Army Institute of Research Human Subjects Protection Branch (#1861E). Patients were predominantly male (98%), with a median age of 26 (IQR 22-30) years, and the majority (85%) reported same-sex partners. Most patients reported a low SPR (n = 78; 55%). A higher proportion of low SPR patients were married or partnered than high SPR patients (29% versus 14%; P = 0.04). Both groups had median DHRS scores in the highest risk category with similar results by reason for HIV screening. The majority of USAF members with incident HIV infection reported a low SPR despite risk factors and CRs identical to high SPR patients. In order to inform HIV prevention strategies in the military, further efforts are needed to educate the military population and providers about HIV risk perception.

The evidence for an increased incidence of sexually transmitted infections (STIs) among patients utilizing HIV pre-exposure prophylaxis (PrEP) has been inconsistent. We assessed the risk of incident STI while on PrEP compared to periods off PrEP among military service members starting PrEP. Incidence rates of chlamydia, gonorrhea, syphilis, hepatitis C virus, and HIV were determined among military service members without HIV prescribed daily oral tenofovir disoproxil fumarate and emtricitabine for HIV PrEP from February 1, 2014 through June 10, 2016. Hazard ratios for incident STIs were calculated using an Anderson-Gill recurrent event proportional hazard regression model. Among 755 male service members, 477 (63%) were diagnosed with incident STIs (overall incidence 21.4 per 100 person-years). Male service members had a significantly lower risk of any STIs (adjusted hazard ratio (aHR) 0.21, 95% CI 0.11–0.40) while using PrEP compared to periods off PrEP after adjustment for socio-demographic characteristics, reasons for initiating PrEP, surveillance period prior to PrEP initiation, and the effect of PrEP on site and type of infection in multivariate analysis. However, when stratifying for anatomical site and type of infection, the risk of extragenital gonorrhea infection (pharyngeal NG: aHR 1.84, 95% CI 0.82–4.13, p = 0.30; rectal NG: aHR 1.23, 95% CI 0.60–2.51, p = 1.00) and extragenital CT infection (pharyngeal CT: aHR 2.30, 95% CI 0.46–11.46, p = 0.81; rectal CT: aHR 1.36, 95% CI 0.81–2.31, p = 0.66) was greater on PrEP compared to off PrEP although these values did not reach statistical significance. The data suggest entry into PrEP care reduced the overall risk of STIs following adjustment for anatomical site of STI and treatment. Service members engaged in PrEP services also receive more STI prevention counseling, which might contribute to decreases in STI risk while on PrEP.

Objective: Validate the performance characteristics of two analyte specific, laboratory developed tests (LDTs) for the quantification of SARS-CoV-2 subgenomic RNA (sgRNA) and viral load on the Hologic Panther Fusion^® using the Open Access functionality. Methods: Custom-designed primers/probe sets targeting the SARS-CoV-2 Envelope gene (E) and subgenomic E were optimized. A 20-day performance validation following laboratory developed test requirements was conducted to assess assay precision, accuracy, analytical sensitivity/specificity, lower limit of detection and reportable range. Results: Quantitative SARS-CoV-2 sgRNA (LDT-Quant sgRNA) assay, which measures intermediates of replication, and viral load (LDT-Quant VLCoV) assay demonstrated acceptable performance. Both assays were linear with an R² and slope equal to 0.99 and 1.00, respectively. Assay precision was evaluated between 4–6 Log10 with a maximum CV of 2.6% and 2.5% for LDT-Quant sgRNA and LDT-Quant VLCoV respectively. Using negative or positive SARS-CoV-2 human nasopharyngeal swab samples, both assays were accurate (kappa coefficient of 1.00 and 0.92). Common respiratory flora and other viral pathogens were not detected and did not interfere with the detection or quantification by either assay. Based on 95% detection, the assay LLODs were 729 and 1206 Copies/mL for the sgRNA and VL load LDTs, respectively. Conclusion: The LDT-Quant sgRNA and LDT-Quant VLCoV demonstrated good analytical performance. These assays could be further investigated as alternative monitoring assays for viral replication; and thus, medical management in clinical settings which could inform isolation/quarantine requirements.

In 2020, preventive measures were implemented to mitigate the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among 600–700 recruits arriving weekly at a basic combat training (BCT) facility in the southern United States. Trainees were sorted into companies and platoons (cocoons) at arrival, tested, quarantined for 14 days with daily temperature and respiratory-symptom monitoring and retested before release into larger groups for training where symptomatic testing was conducted. Nonpharmaceutical measures, such as masking, and social distancing, were maintained throughout quarantine and BCT. We assessed for SARS-CoV-2 transmission in the quarantine milieu. Nasopharyngeal (NP) swabs were collected at arrival and at the end of quarantine and blood specimens at both timepoints and at the end of BCT. Epidemiological characteristics were analyzed for transmission clusters identified from whole-genome sequencing of NP samples. Among 1403 trainees enrolled from 25 August to 7 October 2020, epidemiological analysis identified three transmission clusters (n = 20 SARS-CoV-2 genomes) during quarantine, which spanned five different cocoons. However, SARS-CoV-2 incidence decreased from 2.7% during quarantine to 1.5% at the end of BCT; prevalence at arrival was 3.3%. These findings suggest layered SARS-CoV-2 mitigation measures implemented during quarantine minimized the risk of further transmission in BCT.

Like other congregate living settings, military basic training has been subject to outbreaks of COVID-19. We sought to identify improved strategies for preventing outbreaks in this setting using an agent-based model of a hypothetical cohort of trainees on a U.S. Army post. Our analysis revealed unique aspects of basic training that require customized approaches to outbreak prevention, which draws attention to the possibility that customized approaches may be necessary in other settings, too. In particular, we showed that introductions by trainers and support staff may be a major vulnerability, given that those individuals remain at risk of community exposure throughout the training period. We also found that increased testing of trainees upon arrival could actually increase the risk of outbreaks, given the potential for false-positive test results to lead to susceptible individuals becoming infected in group isolation and seeding outbreaks in training units upon release. Until an effective transmission-blocking vaccine is adopted at high coverage by individuals involved with basic training, need will persist for non-pharmaceutical interventions to prevent outbreaks in military basic training. Ongoing uncertainties about virus variants and breakthrough infections necessitate continued vigilance in this setting, even as vaccination coverage increases.