Effectiveness of a low-cost UVGI chamber for decontaminating filtering facepiece respirators to extend reuse.

In emergencies like the COVID-19 pandemic, the reuse or reprocessing of filtering facepiece respirators (FFRs) may be required to mitigate exposure risk. Research gap: Only a few studies evaluated decontamination effectiveness against SARS-CoV-2 that are practical for low-resource settings. This study aimed to determine the effectiveness of a relatively inexpensive ultraviolet germicidal irradiation chamber to decontaminate FFRs contaminated with SARS-CoV-2. A custom-designed UVGI chamber was constructed to determine the ability to decontaminate seven FFR models including N95s, KN95, and FFP2s inoculated with SARS-CoV-2. Vflex was excluded due to design folds/pleats and UVGI shadowing inside the chamber. Structural and functional integrity tolerated by each FFR model on repeated decontamination cycles was assessed. Twenty-seven participants were fit-tested over 30 cycles for each model and passed if the fit factor was ≥100. Of the FFR models included for testing, only the KN95 model failed filtration. The 3M™ 3M 1860 and Halyard™ duckbill 46727 (formerly Kimberly Clark) models performed better on fit testing than other models for both pre-and-post decontaminations. Fewer participants (0.3 and 0.7%, respectively) passed fit testing for Makrite 9500 N95 and Greenline 5200 FFP2 and only two for the KN95 model post decontamination. Fit testing appeared to be more affected by donning & doffing, as some passed with adjustment and repeat fit testing. A ≥ 3 log reduction of SARS-CoV-2 was achieved for worn-in FFRs namely Greenline 5200 FFP2. Conclusion: The study showed that not all FFRs tested could withstand 30 cycles of UVGI decontamination without diminishing filtration efficiency or facial fit. In addition, SARS-CoV-2 log reduction varied across the FFRs, implying that the decontamination efficacy largely depends on the decontamination protocol and selection of FFRs. We demonstrated the effectiveness of a low-cost and scalable decontamination method for SARS-CoV-2 and the effect on fit testing using people instead of manikins. It is recognized that extensive experimental evidence for the reuse of decontaminated FFRs is lacking, and thus this study would be relevant and of interest in crisis-capacity settings, particularly in low-resource facilities.

Risk factors associated with allergic sensitization and asthma phenotypes among poultry farm workers.

BACKGROUND: This study investigated the risk factors for occupational allergic sensitization and various asthma phenotypes in poultry-workers. METHODS: A cross-sectional study of 230 workers used a modified ECRHS questionnaire, spirometry, FeNO, Phadiatop, and sIgE to poultry farming related allergens. RESULTS: Worker's mean age was 37 ± 9 years, 68% male, 43% current-smokers, 34% atopic, and 5% casual-workers. The prevalence of non-atopic asthma (NAA = 7%) was higher than atopic-asthma (AA = 5%) and probable allergic occupational-asthma (OA = 3%). Sensitization to at least one poultry farming related allergen was 24%. Workers sensitized to chicken-specific-allergens were more likely to be atopic (ORunadj = 20.9, 95%CI: 4.7-93.2) or employed as casual-workers (ORunadj = 6.0, 95%CI: 1.1-35.9). Work-related chest symptoms were associated the rearing-department (ORadj = 3.2, 95%CI: 1.2-8.4) and exposure to high gas/dust/fumes (ORadj = 4.8, 95%CI: 2.4-9.5). Airflow reversibility (ORadj = 10.9, 95%CI: 2.0-60.3) was significantly associated with casual-work status. CONCLUSION: Allergic and non-allergic mechanisms play a role in asthma development among poultry-workers with casual workers demonstrating increased risk.

Assessment of Anti-Bacterial Effectiveness of Hand Sanitizers Commonly Used in South Africa.

Hand sanitizers are used as an alternative to hand washing to reduce the number of viable microorganisms when soap and water are not readily available. This study aimed to investigate the anti-bacterial effectiveness of commercially available hand sanitizers and those commonly used in healthcare and community settings. A mapping exercise was done to select and procure different hand sanitizers (n = 18) from retailers. Five microorganisms implicated in hospital-acquired infections were selected and tested against each hand sanitizer: Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus. Twenty-one volunteers were recruited to do a handprint before and after applying the hand sanitizer. Only four out of eighteen hand sanitizers (22%) were effective against all tested bacterial species, and an equal number (22%) were completely ineffective. Seven hand sanitizers with a label claim of 99.99% were only effective against E. coli. Only five hand sanitizers (27%) effectively reduced bacteria on participants' hands. This study showed that only a fifth of hand sanitizers were effective against selected microorganisms. The findings raise a concern about the effectiveness of hand sanitizers and their role in infection, prevention, and control if not well regulated.

Disease Severity and Comorbidities among Healthcare Worker COVID-19 Admissions in South Africa: A Retrospective Analysis.

Healthcare workers (HCWs) are among the most vulnerable in regard to contracting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Comorbidities are reported to increase the risk for more severe COVID-19 outcomes, often requiring hospitalization. However, the evidence on disease severity and comorbidities among South African HCWs is lacking. This retrospective study analyzed the prevalence of comorbidities among HCW hospitalized with COVID-19 and its association with the severity of outcomes. Data from public and private hospitals in nine provinces of South Africa were extracted from the national hospital surveillance database for COVID-19 admissions. A total of 10,149 COVID-19 HCWs admissions were reported from 5 March 2020 to 31 December 2021. The risk of disease severity among HCWs increased with age, with those older (≥60 years) having seven times the odds of disease severity (aOR 7.0; 95% CI 4.2-11.8) compared to HCWs in the younger age (20-29 years) group. The most commonly reported comorbidity was hypertension (36.3%), followed by diabetes (23.3%) and obesity (16.7%). Hypertension (aOR 1.3; 95% CI 1.0-1.6), diabetes (aOR 1.6; 95% CI 1.3-2.0), and HIV (aOR 1.6; 95% CI 1.2-2.1) were significantly associated with disease severity. In conclusion, age, gender, and existing comorbidities were strong predictors of the prognosis of severe COVID-19 among HCWs in South Africa. The information is important in the development of occupational health policies and vulnerability risk assessments for HCWs in light of future COVID-19 waves or similar outbreaks.

Kaposi's Sarcoma Associated-Herpes Virus (KSHV) Seroprevalence in Pregnant Women in South Africa.

BACKGROUND: Factors previously associated with Kaposi's sarcoma-associated herpesvirus (KSHV) transmission in Africa include sexual, familial, and proximity to river water. We measured the seroprevalence of KSHV in relation to HIV, syphilis, and demographic factors among pregnant women attending public antenatal clinics in the Gauteng province of South Africa. METHODS: We tested for antibodies to KSHV lytic K8.1 and latent Orf73 antigens in 1740 pregnant women attending antenatal clinics who contributed blood to the "National HIV and Syphilis Sero-Prevalence Survey - South Africa, 2001". Information on HIV and syphilis serology, age, education, residential area, gravidity, and parity was anonymously linked to evaluate risk factors for KSHV seropositivity. Clinics were grouped by municipality regions and their proximity to the two main river catchments defined. RESULTS: KSHV seropositivity (reactive to either lytic K8.1 and latent Orf73) was nearly twice that of HIV (44.6% vs. 23.1%). HIV and syphilis seropositivity was 12.7% and 14.9% in women without KSHV, and 36.1% and 19.9% respectively in those with KSHV. Women who are KSHV seropositive were 4 times more likely to be HIV positive than those who were KSHV seronegative (AOR 4.1 95%CI: 3.4 - 5.7). Although, women with HIV infection were more likely to be syphilis seropositive (AOR 1.8 95%CI: 1.3 - 2.4), no association between KSHV and syphilis seropositivity was observed. Those with higher levels of education had lower levels of KSHV seropositivity compared to those with lower education levels. KSHV seropositivity showed a heterogeneous pattern of prevalence in some localities. CONCLUSIONS: The association between KSHV and HIV seropositivity and a lack of common association with syphilis, suggests that KSHV transmission may involve geographical and cultural factors other than sexual transmission.

No evidence of sexual transmission of Kaposi's sarcoma herpes virus in a heterosexual South African population.

BACKGROUND: The transmission of Kaposi's sarcoma herpes virus (KSHV) in men who have sex with men is clearly associated with sexual risk factors, but evidence of heterosexual transmission of KSHV is conflicting. METHODS: Sera were obtained from 2103 South African individuals (862 miners, 95 sex workers, 731 female and 415 male township residents; mean age 33.2 years; +/- 10.1). All sera were tested for antibodies to KSHV lytic K8.1 and latent Orf73, HIV, gonococcus, herpes simplex virus type 2 (HSV-2), syphilis and chlamydia. Information on social, demographic and high-risk sexual behavior was linked to laboratory data, to evaluate risk factors, expressed as odds ratios (95% confidence interval) for KSHV. RESULTS: Overall KSHV and HIV prevalences were 47.5 and 40%, respectively (P = 0.43). The risk of HIV infection was highest in sex workers then female residents and miners, compared with male residents (P < 0.001). HSV-2 infection was highly prevalent (66%) and lower, but still substantial, prevalences (6-8%) were observed for other sexually transmitted infections (STI). No significant difference in KSHV infection was observed among the residential groups (P > 0.05). KSHV was not associated with any of the STI or any measures of sexual behavior (P > 0.05). CONCLUSION: The pattern of HIV and STI in sex workers suggests high rates of high-risk sexual behavior in this population. The lack of association with high-risk sexual behavior, particularly in sex workers, and with any markers of STI strongly suggest that the sexual mode does not play a significant role in KSHV transmission in this South African population.

Transmission of Kaposi sarcoma-associated herpesvirus between mothers and children in a South African population.

BACKGROUND: To assess whether Kaposi sarcoma-associated herpesvirus (KSHV) with or without HIV coinfection in South African mothers is associated with higher KSHV seropositivity in their children. METHODS: We tested sera from 1287 South African children and 1179 mothers using assays for KSHV lytic K8.1 and latent ORF73 antigens. We computed odds ratios (ORs) and 95% confidence intervals (CIs) to assess associations between KSHV serostatus and risk factors. RESULTS: KSHV seroprevalence was 15.9% (204 of 1287 subjects) in children and 29.7% (350 of 1179 subjects) in mothers. The risk of KSHV seropositivity was significantly higher in children of KSHV-seropositive mothers compared with those of KSHV-seronegative mothers. The HIV status of mothers was marginally associated with an increased risk of KSHV seropositivity in their children (OR = 1.6, 95% CI: 1.0 to 2.6; P = 0.07). KSHV seroprevalence was significantly higher in HIV-infected subjects (P = 0.0005), and HIV-infected subjects had significantly higher lytic and latent KSHV antibody levels than HIV-negative subjects. CONCLUSIONS: The risk of acquisition of KSHV was higher among children of KSHV-seropositive mothers. Although KSHV seroprevalence was significantly higher in children and mothers who were infected with HIV, the HIV status of the mother was only marginally associated with an increased risk of KSHV seropositivity in the child.