Invasive group A streptococcal infection outbreaks of typeemm118 in a long-term care facility, and of type emm74 in the homeless population, Montréal, Quebec

Infectious Diseases Among People Experiencing Homelessness: A Systematic Review of the Literature in the United States and Canada, 2003-2022

Homelessness increases the risk of acquiring an infectious disease. We conducted a systematic review of the literature to identify quantitative data related to infectious diseases and homelessness. We searched Google Scholar, PubMed, and SCOPUS for quantitative literature published from January 2003 through December 2022 in English from the United States and Canada. We excluded literature on vaccine-preventable diseases and HIV because these diseases were recently reviewed. Of the 250 articles that met inclusion criteria, more than half were on hepatitis C virus or Mycobacterium tuberculosis. Other articles were on COVID-19, respiratory syncytial virus, Staphylococcus aureus, group A Streptococcus, mpox (formerly monkeypox), 5 sexually transmitted infections, and gastrointestinal or vectorborne pathogens. Most studies showed higher prevalence, incidence, or measures of risk for infectious diseases among people experiencing homelessness as compared with people who are housed or the general population. Although having increased published data that quantify the infectious disease risks of homelessness is encouraging, many pathogens that are known to affect people globally who are not housed have not been evaluated in the United States or Canada. Future studies should focus on additional pathogens and factors leading to a disproportionately high incidence and prevalence of infectious diseases among people experiencing homelessness.

Dermatologic conditions and risk factors in people experiencing homelessness (PEH): systematic review

Limited data is present that characterizes dermatological conditions and their risk factors in people experiencing homelessness (PEH).We conducted a systematic review to investigate the types of dermatological conditions in PEH, their risk factors, and provide solutions when providing dermatological care to this patient population. We searched PubMed, EMBASE and Cochrane for articles written in English from 2012 to 2022. The last search was performed on December 27, 2022. Twelve studies met the inclusion criteria. Fifty-eight percent of the studies took place in the USA (n = 7) and 42% of studies took place in Canada (n = 5). Prevalent dermatological conditions included, skin cancer, cutaneous manifestations of malnutrition, cutaneous diphtheria, Group A Streptococcus infection (iGAS), lice, atopic dermatitis, acne, sexually transmitted infections (STIs), and Staphylococcus aureus infections. Risk factors included substance use disorder, skin trauma, not having access to sunscreen or hats, unstable housing, higher exposure to extreme weather, and higher mobility. Due to studies being conducted in the USA or Canada, results may not be generalizable. This systematic review strongly suggests that many dermatological conditions prevalent in PEH can be contributed to poor skin integrity. Better measures can significantly reduce certain dermatological conditions by improving access to dermatological care.

Incidence and clinical and microbiological features of invasive and probable invasive streptococcal group A infections in children and adults in the Brussels-Capital Region, 2005-2020

Assess the incidence, risk factors, clinical and microbiological features, and outcome of both probable invasive and invasive group A Streptococcus (GAS) infections in children and adults in the BrusselsCapital Region between 2005 and 2020. A retrospective, multicentric study was performed in three university hospitals in Brussels. Patients were identified through the centralized laboratory information system. Epidemiological and clinical data were collected from patients' hospital records. A total of 467 cases were identified. Incidence has increased from 2.1 to 10.9/100,000 inhabitants between 2009 and 2019 in non-homeless adults while it was above 100/100,000 on homeless in years with available denominators. Most of GAS were isolated from blood (43.6%), and the most common clinical presentation was skin and soft tissue infections (42.8%). A third of all the patients needed surgery, a quarter was admitted to the intensive care unit, and 10% of the adult patients died. Wounds and chickenpox disease were the main risk factors for children. Tobacco, alcohol abuse, wounds or chronic skin lesion, being homeless, and diabetes were identified as major predisposing factors for adults. The most common emm clusters were D4, E4, and AC3; 64% of the isolates were theoretically covered by the 30-valent M-protein vaccine. The burden of invasive and probable invasive GAS infections is on the rise in the studied adult population. We identified potential interventions that could contribute to decrease this burden: appropriate care of wounds, specifically among homeless and patients with risk factors such as diabetes and systematic chickenpox vaccination for children.

Echocardiographic Parameters, Clinical Profile and Presence of Streptococcus pyogenes Virulent Genes in Pharyngitis and Rheumatic Fever

Streptococcus pyogenes is a gram positive pathogen causing pharyngitis, mild infections to chronic complications (Rheumatic Heart Disease, RHD). In this study, echocardiographic and clinical profile in pharyngitis, rheumatic fever patients were compared with virulent genes emm, spe A, spe B and sof. Nearly 107 subjects were classified into Group I – Pharyngitis (n=30), Group II – Rheumatic Fever (n=30) and Group III – healthy controls (n=47). The isolated S.pyogenes from Group I and Group II patient’s throat swab were subjected to 16S rRNA gene sequence. Multiplex PCR was done for identification of virulent genes. Electrocardiogram and Echocardiography was done for all the groups. For statistical analysis ANOVA and t-test were used. Comparison between groups were done by Tukey’s Multiple Comparison test. Among 107 isolates, 16.7% emm gene were detected in Group I and 23.3% in Group II, 56.67 % of spe B in Group I and 73.33 % in Group II, 36.67% of sof gene in Group I and 40% in Group II. Mitral Regurgitation was most commonly encountered in rheumatic fever. Hemoglobin (<0.001) and RDW (<0.001) was significantly lower in Rheumatic Fever whereas Platelet count (<0.001) and Neutrophil (<0.001) was significantly higher when compared with control subjects by Tukey’s Multiple Comparison test. When we compared the genetic relationship with the Echocardiographic findings, presence of one, two or three genes showed moderate to severe regurgitation in Rheumatic Fever subjects.

Hand hygiene during the COVID-19 pandemic among people experiencing homelessness-Atlanta, Georgia, 2020

People experiencing homelessness are at risk for coronavirus disease 2019 (COVID-19) and may experience barriers to hand hygiene, a primary recommendation for COVID-19 prevention. We conducted in-depth interviews with 51 people experiencing sheltered and unsheltered homelessness in Atlanta, Georgia during May 2020 to August 2020 to (1) describe challenges and opportunities related to hand hygiene and (2) assess hand hygiene communication preferences. The primary hand hygiene barrier reported was limited access to facilities and supplies, which has disproportionately impacted people experiencing unsheltered homelessness. This lack of access has reportedly been exacerbated during COVID-19 by the closure of public facilities and businesses. Increased access to housing and employment were identified as long-term solutions to improving hand hygiene. Overall, participants expressed a preference for access to facilities and supplies over hand hygiene communication materials.

Understanding Dermatologic Concerns Among Persons Experiencing Homelessness: A Scoping Review and Discussion for Improved Delivery of Care

There is a paucity of information surrounding dermatologic care for persons experiencing homelessness (PEH). This scoping review aims to map existing literature and provide a summary of the most common cutaneous manifestations among PEH, risk factors for dermatologic disease, describe any reported interventions, as well as identify research gaps for future studies. Search strategies developed for MEDLINE and hand searching yielded 486 articles. Out of the 486 articles screened, 93 articles met the inclusion criteria. The majority were cohort studies, cross-sectional studies, and case-control studies concentrated in North America and Europe. Excluding the pediatric population, the prevalence of dermatologic conditions ranged from 16.6% to 53.5%. Common skin conditions described in PEH were: acne, psoriasis, seborrheic dermatitis, atopic dermatitis, and lichen simplex chronicus. There were no studies comparing the extent or severity of these cutaneous diseases in PEH and the general population. PEH have a higher prevalence of skin infections and non-melanoma skin cancers. This scoping review has direct implications on public health interventions for PEH and highlights the need for evidence-based interventions to provide optimum and safe dermatologic healthcare for PEH. We propose several recommendations for improved care delivery, including addressing upstream factors and comorbidities impacting skin health, providing trauma informed care, reducing barriers to care, preventing and managing skin conditions, as well as including PEH in the planning and implementation of any proposed intervention.

Three sequential outbreaks of Group A Streptococcus over a two-year period at the Canadian Forces Leadership and Recruit School, St. Jean Garrison, Québec

Background

Since December 2016, the basic military training (BMT) facility for the Canadian Armed Forces (CAF) has experienced repeated outbreaks of Group A Streptococcus (GAS). In 2018, a voluntary mass antibiotic prophylaxis (MAP) program was implemented to interrupt GAS transmission among recruits. The objective of this study was to describe the epidemiology of three GAS outbreaks and a period of increased pharyngitis infections at the CAF BMT facility in Québec over a two-year span, and to detail the prevention and control measures implemented to mitigate the risk to recruit health.

Methods

Descriptive data were collected on invasive and severe GAS cases along with laboratory data including genotyping of throat swabs from recruits presenting with pharyngitis. A laboratory-based acute respiratory infection surveillance system was used to aid in monitoring and decision-making. Close contacts of recruits were assessed for asymptomatic GAS carriage and MAP adverse events surveillance was conducted.

Results

Three distinct GAS outbreaks occurred at the Canadian Forces Leadership and Recruit School totaling eight invasive (iGAS) and 13 severe (sGAS) cases over two years. All iGAS/sGAS cases, apart from one instructor, were among recruits. The predominant strain in all three outbreaks was type emm6.4. A total of 11,293 recruits received MAP (penicillin G benzathine or azithromycin) between March 7, 2018 and November 18, 2019. There were eight reported serious adverse events related to penicillin administration.

Conclusion

The CAF BMT facility experienced three GAS outbreaks over the course of two years, and despite the use of enhanced hygiene measures, only MAP has been effective in quelling these outbreaks.

Risk factors associated with group A Streptococcus acquisition in a large, urban homeless shelter outbreak

OBJECTIVE

Group A Streptococcus (GAS) is a frequent cause of outbreaks in healthcare institutions, yet outbreak reports in the literature from homeless shelters are less common, despite an increased risk of severe GAS infection in homeless populations. In 2016, we conducted a case-control study to identify significant risk factors associated with GAS acquisition in a protracted, 19-month outbreak of GAS in a large, urban men's homeless shelter in Ontario, Canada.

METHODS

Cases (individuals with either clinical GAS emm74 infection or asymptomatic carriers of GAS emm74) and controls were identified from shelter residents from February to September 2016. Information on demographics, clinical presentation, pre-existing health conditions, and risk factors for GAS transmission were collected for all study participants from a variety of sources, including the public health notifiable disease information system, electronic health records, the shelter electronic information system, and interviews with client services workers.

RESULTS

From the multivariable logistic regression model, younger individuals (OR 9.1; 95% CI 1.57-52.9), those with previous skin conditions (OR 56.2; 95% CI 2.73-1160), and those with recent wounds (with wound care: OR 51.5, 95% CI 8.86-299, and without wound care: OR 77.4, 95% CI 7.38-812) were found to be at increased risk of acquiring GAS in this outbreak.

CONCLUSION

The outbreak investigation clearly demonstrated the need for improved wound care and infection prevention and control practices, for early screening and detection of skin and soft tissue infections, and for a comprehensive, integrated electronic information system in homeless shelters.

Evaluation of Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry and ClinPro Tools as a Rapid Tool for Typing Streptococcus pyogenes

Background

Timely strain typing of group A Streptococci (GAS) is necessary to guide outbreak recognition and investigation. We evaluated the use of (matrix-assisted laser desorption ionization time-of-flight mass spectrometry) combined with cluster analysis software to rapidly distinguish between related and unrelated GAS isolates in real-time.

Methods

We developed and validated a typing model using 177 GAS isolates with known emm types. The typing model was created using 43 isolates, which included 8 different emm types, and then validated using 134 GAS isolates of known emm types that were not included in model generation.

Results

Twelve spectra were generated from each isolate during validation. The overall accuracy of the model was 74% at a cutoff value of 80%. The model performed well with emm types 4, 59, and 74 but showed poor accuracy for emm types 1, 3, 12, 28, and 101. To evaluate the ability of this tool to perform typing in an outbreak situation, we evaluated a virtual outbreak model using a “virtual outbreak strain; emm74” compared with a non-outbreak group or an “outgroup “ of other emm types. External validation of this model showed an accuracy of 91.4%.

Conclusions

This approach has the potential to provide meaningful information that can be used in real time to identify and manage GAS outbreaks. Choosing isolates characterized by whole genome sequencing rather than emm typing for model generation should improve the accuracy of this approach in rapidly identifying related and unrelated GAS strains.