Trop. Med. Infect. Dis., Volume 7, Issue 2 (February 2022) – 21 articles

The prevalence of visual impairment (VI) continues to rise, despite efforts to reduce it. The burden of disease negatively impacts the quality of life, education opportunities, and other developments in various communities. Henceforth, this study aimed to determine and quantify the major causes of VI in South Africa, to ensure accurate interventions in addressing them and to reduce the burden of ocular disease in that context. A systematic scoping review was conducted to map evidence on VI and ocular diseases, using the PRISMA-P guidelines. English studies were searched for on PubMed, Google Scholar, and EBSCOhost using various search terms. The eligible articles underwent screening and ultimately data extraction to identify major causes of VI in South Africa. A meta-analysis further resulted in pooled prevalence estimates (PPE) using the Inverse Variance Heterogeneity (IVhet) model. Of the 13,527 studies screened at three levels, 10 studies met the inclusion criteria for the final review; however, 9 studies were eligible for quality assessment performed by two independent reviewers. The quality index for the included studies was 71.1%. The prevalence of VI was 2% for blindness and 12% for moderate and severe visual impairment (MSVI). Pooled prevalence identified uncorrected refractive error (URE) (43%), cataract (28%), glaucoma (7%), and diabetic retinopathy (4%) as major causes of MSVI. The leading causes of blindness were untreated cataracts (54%), glaucoma (17%), and diabetic retinopathy (57%). Ocular diseases causing VI are avoidable and similar to those of low-to-middle income countries. MSVI were caused by URE, cataract, glaucoma, and diabetic retinopathy. Blindness was mainly caused by cataracts, glaucoma, and diabetic retinopathy. A strategic plan to manage these conditions would largely reduce the burden of VI in the country. Early screenings and interventions to maximize care at primary health levels would decrease the burden of avoidable blindness in the country significantly. Full article

Soil-transmitted helminth infections are most prevalent in rural populations. Village health volunteers (VHVs) are the key individuals for Thai primary healthcare. Therefore, this study aimed to investigate the knowledge, attitudes, and practices regarding soil-transmitted helminthiasis in VHVs. A questionnaire survey was conducted among 552 VHVs randomly selected from four subdistricts in a southern province of Thailand. Sociodemographic variables and information regarding the knowledge, attitudes, and practices related to soil-transmitted helminthiasis were collected using a structured questionnaire. The results demonstrated that VHVs had poor knowledge (70.47%) and practices (66.49%); however, 69.57% had good attitudes. Most VHVs had inadequate knowledge and practices regarding soil-transmitted helminthiasis. VHVs who had been trained in parasitic infection control measures were 2.18 times more likely to have good knowledge. VHVs with a monthly family income of more than 307 USD were 1.58 times more likely to have a good attitude. VHVs with good knowledge were more likely to have good practices. In conclusion, the development of training programs and health promotion should be considered to enhance the knowledge, attitudes, and practices related to soil-transmitted helminthiasis in VHVs, who are the key individuals for providing health education to community members. Full article

The order Rickettsiales includes species that cause a range of human diseases such as human granulocytic anaplasmosis (Anaplasma phagocytophilum), human monocytic ehrlichiosis (Ehrlichia chaffeensis), scrub typhus (Orientia tsutsugamushi), epidemic typhus (Rickettsia prowazekii), murine typhus (R. typhi), Mediterranean spotted fever (R. conorii), or Rocky Mountain spotted fever (R. rickettsii). These diseases are gaining a new momentum given their resurgence patterns and geographical expansion due to the overall rise in temperature and other human-induced pressure, thereby remaining a major public health concern. As obligate intracellular bacteria, Rickettsiales are characterized by their small genome sizes due to reductive evolution. Many pathogens employ moonlighting/multitasking proteins as virulence factors to interfere with multiple cellular processes, in different compartments, at different times during infection, augmenting their virulence. The utilization of this multitasking phenomenon by Rickettsiales as a strategy to maximize the use of their reduced protein repertoire is an emerging theme. Here, we provide an overview of the role of various moonlighting proteins in the pathogenicity of these species. Despite the challenges that lie ahead to determine the multiple potential faces of every single protein in Rickettsiales, the available examples anticipate this multifunctionality as an essential and intrinsic feature of these obligates and should be integrated into available moonlighting repositories. Full article

Few data are available on Campylobacter spp. presence in chickens in Ethiopia. Due to its importance for both the poultry sector and public health, a sampling activity was planned to evaluate Campylobacter spp. presence in layer farms in Bishoftu and Mojo, Central Ethiopia. Twenty cloacal pooled samples were collected and tested with molecular assays for detection and Sanger-sequenced for species identification. As a secondary aim, samples were also tested for Salmonella spp. by PCR, and all samples were negative. On the other hand, 70% of cloacal swab pools were positive for Campylobacter spp.: 71.4% of the positive samples belonged to C. jejuni species, 21.4% to C. avium and 7.1% to C. helveticus. Campylobacter spp. was identified in almost all farms regardless of farm and flock size, age and hybrid types of the birds and antimicrobial treatment. Campylobacter jejuni is a common finding in chickens, whereas species such as C. avium and C. helveticus were newly reported in Ethiopia, revealing a variability that needs to be monitored in light of the public health significance of this pathogen. Full article

Background: Reproductive health remains a major health concern in developing countries such as Papua New Guinea (PNG). The prevalence of human immunodeficiency virus (HIV) in PNG is the highest in the Southern Pacific region, with women having a higher risk of contracting the infection. Hence, there have been several policies aimed at mitigating the spread of the disease. One of these policies include the use of mass media as a health promotion tool to educate the population on the risk of the disease. Therefore, this study aimed at investigating the association of mass media to HIV testing among women. Methods: Data were obtained from the PNG Demographic and Health Survey (DHS) of 2019. A total of 15,005 reproductive-age women was included in this analysis. Results: The results showed that women with low (aOR = 1.63, 95% CI: 1.39, 1.90) and high (aOR = 1.53, 95% CI: 1.36, 1.72) media exposure were more likely to undertake HIV testing compared to those with no media exposure. Compared to no education, women with incomplete primary (aOR = 1.22, 95% CI: 1.06, 1.40), complete primary (aOR = 1.56, 95% CI: 1.30, 1.87), incomplete secondary (aOR = 2.18, 95% CI: 1.85, 2.58), complete secondary (aOR= 2.33, 95% CI: 1.77, 3.09) and higher (aOR = 3.38, 95% CI: 2.57, 4.46) education were more likely to undertake HIV testing. Compared to women with the poorest wealth index, women with richer indexes were more likely to undertake HIV testing. Women living in rural areas were less likely to undertake HIV testing (aOR = 0.72, 95% CI: 0.63, 0.82). However, marital status, knowledge of transmission and religion were not associated with HIV testing. Conclusion: In conclusion, this study provides strong evidence that mass media exposure increases the likelihood of HIV testing in women of reproductive age in PNG. Mass media campaigns would serve as a cost-effective health promotion tool against the spread of disease. Full article

The necessity of drug combinations to treat leishmaniasis came to the surface mainly because of the toxicity of current treatments and the emergence of resistant strains. The calpain inhibitor MDL28170 has previously shown anti-Leishmania activity, therefore its use in association with standard drugs could provide a new alternative for the treatment strategy against leishmaniasis. In this study, we analyzed the potential of the combination of MDL28170 and the antileishmanial drug amphotericin B against Leishmania amazonensis and Leishmania chagasi. The compounds were tested in the combination of the ½ × IC₅₀ value of MDL28170 plus the ¼ × IC₅₀ value of amphotericin B, which led to an increment in the anti-promastigote activity when compared to the single drug treatments. This drug association revealed several and severe morphophysiological changes on parasite cells, such as loss of plasma membrane integrity, reduced size of flagellum, and depolarization of mitochondrial membrane potential besides increased reactive oxygen species production. In addition, the combination of both drugs had a deleterious effect on the Leishmania–macrophage interaction, reflecting in a significant anti-amastigote action, which achieved a reduction of 50% in the association index. These results indicate that the combination treatment proposed here may represent a new alternative for leishmaniasis chemotherapy. Full article

Abattoir workers may contract Q fever by inhalation of Coxiella burnetii bacteria in aerosols generated by slaughtering livestock, or in contaminated dust. We estimated the seroprevalence of C. burnetii and examined the associated factors in a survey of South African abattoir workers. Coxiella burnetii seropositivity was determined by detection of IgG antibodies against C. burnetii phase II antigen. Logistic regression, adjusted for clustering and sampling fraction, was employed to analyze risk factors associated with C. burnetii seropositivity. Among 382 workers from 16 facilities, the overall seroprevalence was 33% (95% confidence interval (CI): 28–38%) and ranged from 8% to 62% at the facility level. Prolonged contact with carcasses or meat products (odds ratio (OR): 4.6, 95% CI: 1.51–14.41) and prior abattoir or butchery work experience (OR: 1.9, 95% CI: 1.13–3.17) were associated with C. burnetii seropositivity. In contrast, increasing age and livestock ownership were inversely associated. Precautions to protect abattoir personnel from Q fever are discussed. Full article

Infectious diseases caused by nontuberculous mycobacteria (NTM) are increasingly common. This retrospective cohort study examined factors associated with outcomes in patients from Shanghai who had NTM pulmonary disease (NTMPD) from January 2014 to December 2018. The causative bacterial species, drug susceptibility test results, treatment outcomes, sputum culture conversion rate, and risk factors associated with treatment failure were determined. The most common species were Mycobacterium avium complex (MAC) (50%), M. abscessus (28%), and M. kansasii (15%). Over five years, the proportions of M. kansasii and M. abscessus increased, and that of MAC decreased. The treatment success rate was significantly greater for patients infected with M. kansasii (89.9%) than MAC (65.0%, p < 0.001) and M. abscessus (36.1%, p < 0.001). Multivariate analysis indicated the risk factors for treatment failure were pathogenic NTM species (M. abscessus: aOR = 9.355, p < 0.001; MAC: aOR = 2.970, p < 0.001), elevated ESR (>60 mm/h: aOR = 2.658, p < 0.001), receipt of retreatment (aOR = 2.074, p < 0.001), and being middle-aged or elderly (>60 years-old: aOR = 1.739, p = 0.021; 45–60 years-old: aOR = 1.661, p = 0.034). The main bacterial species responsible for NTMPD were MAC, M. abscessus, and M. kansasii. Patients who were infected by M. abscessus or MAC, with elevated ESR, received retreatment, and were middle-aged or elderly had an increased risk of treatment failure. Full article

Pediatric patients with untreated tuberculosis infection (TBI), also called latent TBI, are at risk of progression to active TB disease. The primary aim of this study was to identify factors associated with higher rates of missed appointments and failure to complete therapy for pediatric patients with TBI. A secondary aim was to determine the impact of the COVID-19 pandemic and the rise of telehealth on TBI missed appointment rates. We first performed a retrospective chart review of 129 pediatric patients referred to the free Yale Pediatric Winchester Chest Tuberculosis Clinic from 2016–2019. Associations between demographic/clinical variables and missed appointments/failure to complete therapy were analyzed using univariate and bivariate chi-square tests. Language, lack of primary provider, and distance to clinic were the main contributors to missed appointments and poor treatment adherence. There was an association between the number of missed appointments and failure to complete treatment (p = 0.050). A second cohort of 29 patients was analyzed from January–December 2021 when telehealth was offered for follow-up appointments. Of these follow-up visits, 54% were conducted via telehealth, and the clinic’s missed appointment rate dropped significantly from 16.9% to 5.8% during this time frame (p = 0.037). These data demonstrate that telehealth is accepted as an alternative by patients for follow-up TBI visits. Full article

Francisella is an intracellular, fastidious, Gram-negative bacterium that is difficult to identify using routine microbiological methods in the laboratory. We studied the isolation of Francisella sp. (strain IDAMR664) from the blood of a patient with anti-interferon-γ (IFN-γ) autoantibodies who presented with septicemia and cholestatic hepatitis. Analysis of the strain IDAMR664 genome sequence revealed the isolate was closely related to the strain GA01-2794 that had been isolated from a human in the USA. In addition, it was clustered with F. orientalis, a fish pathogen. The isolate contained several virulence factors and had Francisella pathogenicity island pattern no. 3. Full article

Disseminated Acanthamoeba species infection is likely an underrecognized and underdiagnosed opportunistic infection in patients with advanced human immunodeficiency virus (HIV) disease in South Africa. It presents a unique clinical challenge in that the diagnosis can be difficult to establish and management options are limited in low-resource settings. To our knowledge, there is a paucity of literature to date on the successful use of combination treatment options for patients in low-resource settings without access to miltefosine. We present a case describing the clinical improvement of disseminated Acanthamoeba infection in a patient with advanced HIV using a non-miltefosine-based treatment regimen. The case serves to highlight that Acanthamoeba sp. infection should be considered as a differential diagnosis for nodular and ulcerative cutaneous lesions in patients with advanced HIV in South Africa, and that although there are alternative options for combination treatment in countries without access to miltefosine, efforts should be made to advocate for better access to miltefosine for the treatment of acanthamoebiasis in South Africa. Full article

Micafungin is the empiric antifungal agent of choice for the treatment of invasive candidiasis (IC). Pathophysiologic changes that occur in obese and/or critically ill patients can alter micafungin serum concentrations and the probability of target attainment. Although high doses of micafungin have been shown to be safe, clinical outcomes have not been widely evaluated. We conducted a single-center, retrospective observational study evaluating safety and clinical outcomes among adult patients treated with ≥200 mg of micafungin for ≥3 days for proven IC from 1 September 2013 through 1 September 2021. Twenty-three unique encounters for 21 patients were evaluated. The median BMI and APACHE II scores were 37.1 (IQR 28.8–48.9) and 24 (IQR 17.7–31), respectively. The median average daily dose of micafungin was 300 mg (IQR 275–400). Patients were treated with high-dose (HD) micafungin for the entirety of their echinocandin course in 15 encounters (65.2%). Transaminases remained stable, while a trend towards increased alkaline phosphatase was observed. A total of four deaths occurred (17.4%). Patients that died were predominantly young, Hispanic males who were obese and/or critically ill. Future studies are needed to determine the necessity and appropriate placement of HD micafungin in obese and/or critically ill patients. Full article

Background: The relationship between HIV (human immunodeficiency virus) and COVID-19 clinical outcome is uncertain, with conflicting data and hypotheses. We aimed to assess the prevalence of people living with HIV (PLWH) among COVID-19 cases and whether HIV infection affects the risk of severe COVID-19 or related death at the global and continental level. Methods: Electronic databases were systematically searched in July 2021. In total, 966 studies were screened following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Narratives were synthesised and data pooled for the global and continental prevalence of HIV–SARS-CoV-2 coinfection. The relative risks of severity and mortality in HIV-infected COVID-19 patients were computed using a random-effect model. Risk of bias was assessed using the Newcastle–Ottawa score and Egger’s test, and presented as funnel plots. Results: In total, 43 studies were included involving 692,032 COVID-19 cases, of whom 9097 (1.3%) were PLWH. The global prevalence of PLWH among COVID-19 cases was 2% (95% CI = 1.7–2.3%), with the highest prevalence observed in sub-Saharan Africa. The relative risk (RR) of severe COVID-19 in PLWH was significant only in Africa (RR = 1.14, 95% CI = 1.05–1.24), while the relative risk of mortality was 1.5 (95% CI = 1.45–2.03) globally. The calculated global risk showed that HIV infection may be linked with increased COVID-19 death. The between-study heterogeneity was significantly high, while the risk of publication bias was not significant. Conclusions: Although there is a low prevalence of PLWH among COVID-19 cases, HIV infection may increase the severity of COVID-19 in Africa and increase the risk of death globally. Full article

Substance use (SU) is associated with poor rifampicin-resistant tuberculosis (RR-TB) treatment outcomes. In 2017, a SBIRT (SU screening-brief intervention-referral to treatment) was integrated into routine RR-TB care in Khayelitsha, South Africa. This was a retrospective study of persons with RR-TB who were screened for SU between 1 July 2018 and 30 September 2020 using the ASSIST (Alcohol, Smoking and Substance Involvement Screening Test). Here we describe outcomes from this program. Persons scoring moderate/high risk received a brief intervention and referral to treatment. Overall, 333 persons were initiated on RR-TB treatment; 38% (n = 128) were screened for SU. Of those, 88% (n = 113/128) reported SU; 65% (n = 83/128) had moderate/high risk SU. Eighty percent (n = 103/128) reported alcohol use, of whom 52% (n = 54/103) reported moderate/high risk alcohol use. Seventy-seven persons were screened for SU within ≤2 months of RR-TB treatment initiation, of whom 69%, 12%, and 12% had outcomes of treatment success, loss to follow-up and death, respectively. Outcomes did not differ between persons with no/low risk and moderate/high risk SU or based on the receipt of naltrexone (p > 0.05). SU was common among persons with RR-TB; there is a need for interventions to address this co-morbidity as part of “person-centered care”. Integrated, holistic care is needed at the community level to address unique challenges of persons with RR-TB and SU. Full article

COVID-19 and dengue disease are challenging to tell apart because they have similarities in clinical and laboratory features during the acute phase of infection, leading to misdiagnosis and delayed treatment. The present study evaluated peripheral blood cell count accuracy to distinguish COVID-19 non-critical patients from non-severe dengue cases between the second and eleventh day after symptom onset. A total of 288 patients infected with SARS-CoV-2 (n = 105) or dengue virus (n = 183) were included in this study. Neutrophil, platelet, and lymphocyte counts were used to calculate the neutrophil–lymphocyte ratio (NLR), the platelet–lymphocyte ratio (PLR), and the neutrophil–lymphocyte*platelet ratio (NLPR). The logistic regression and ROC curves analysis revealed that neutrophil and platelet counts, NLR, LPR, and NLPR were higher in COVID-19 than dengue. The multivariate predictive model showed that the neutrophils, platelets, and NLPR were independently associated with COVID-19 with a good fit predictive value (p = 0.1041). The neutrophil (AUC = 0.95, 95% CI = 0.84–0.91), platelet (AUC = 0.89, 95% CI = 0.85–0.93) counts, and NLR (AUC = 0.88, 95% CI = 0.84–0.91) were able to discriminate COVID-19 from dengue with high sensitivity and specificity values (above 80%). Finally, based on predicted probabilities on combining neutrophils and platelets with NLR or NLPR, the adjusted AUC was 0.97 (95% CI = 0.94–0.98) to differentiate COVID-19 from dengue during the acute phase of infection with outstanding accuracy. These findings might suggest that the neutrophil, platelet counts, and NLR or NLPR provide a quick and cost-effective way to distinguish between dengue and COVID-19 in the context of co-epidemics in low-income tropical regions. Full article

Ireland is a country with a low incidence of tuberculosis (TB) (5.6 cases per 100,000 population in 2019) that should be aiming for TB elimination (fewer than 1 case per million of population). To achieve TB elimination in low-incidence countries, programmatic latent tuberculosis infection (LTBI) management is important. This requires high-quality latent tuberculosis infection (LTBI) screening. Aim: To assess the quality of LTBI screening in a tertiary centre in Ireland using a framework. Methods: A retrospective review of the health care records of patients screened for TB in a tertiary centre in Ireland using an interferon-gamma release assay (IGRA) between 2016 and 2018 was performed. Three domains from the Institute of Medicine framework for health care quality, effectiveness, efficiency, and equity, were applied to measure the quality of LTBI screening. Results: Forty patients had LTBI and an indication for treatment, of whom 20% (8/40) were not offered treatment by the health care provider, 2.5% (1/40) did not accept treatment, and 10% (4/40) did not complete treatment. Seventy-five percent (6/8) of patients not offered treatment were non-Irish. The cost of screening per LTBI case identified was EUR 2048. Conclusions: This study evaluated the quality of LTBI screening using a framework and identified that LTBI screening in this tertiary centre needs to be scaled and expanded, and that treatment initiation needs to be improved, particularly among non-Irish nationals. Full article

Rickettsiosis is an important cause of febrile illness among travellers visiting Southeast Asia (SEA). The true incidence of rickettsiosis is underestimated; however, murine typhus and scrub typhus are widely distributed across SEA. Among travellers visiting SEA, scrub typhus was mostly reported from Thailand, whereas murine typhus was frequently found in Indonesia. Although most cases are self-limited or present with mild symptoms, a few cases with severe clinical manifestations have been reported. Doxycycline remains the key treatment of rickettsiosis. Some travellers, such as backpackers, trekkers, or cave explorers, are at a higher risk for rickettsiosis than others. Therefore, in resource-limited conditions, empirical treatment should be considered in these travellers. The coronavirus disease 2019 (COVID-19) pandemic has contributed to difficulty in the diagnosis of rickettsiosis because of the clinical similarities between these diseases. In addition, physical distancing mandated by COVID-19 management guidelines limits accurate physical examination, resulting in misdiagnosis and delayed treatment of rickettsiosis. This review summarises the characteristics of murine typhus and scrub typhus, describes travel-associated rickettsiosis, and discusses the impact of the COVID-19 pandemic on rickettsiosis. Full article

Schistosomiasis is a neglected tropical disease (NTD) found throughout tropical and subtropical Africa. In Madagascar, the condition is widespread and endemic in 74% of all administrative districts in the country. Despite the significant burden of the disease, high-resolution risk maps have yet to be produced to guide national control programs. This study used an ecological niche modeling (ENM) and precision mapping approach to estimate environmental suitability and disease transmission risk. The results show that suitability for schistosomiasis is widespread and covers 264,781 km² (102,232 sq miles). Covariates of significance to the model were the accessibility to cities, distance to water, enhanced vegetation index (EVI), annual mean temperature, land surface temperature (LST), clay content, and annual precipitation. Disease transmission risk is greatest in the central highlands, tropical east coast, arid-southwest, and northwest. An estimated 14.9 million people could be at risk of schistosomiasis; 11.4 million reside in rural areas, while 3.5 million are in urban areas. This study provides valuable insight into the geography of schistosomiasis in Madagascar and its potential risk to human populations. Because of the focal nature of the disease, these maps can inform national surveillance programs while improving understanding of areas in need of medical interventions. Full article

Hepatitis C virus (HCV) is a significant public health problem, and the elimination of its infection by 2031 is a global goal. However, due to insufficient testing, lack of linkage to care (LTC) and treatment, Libya may be far from achieving this goal. This study aimed to explore HCV testing, the care and treatment of infected people, and to assess the burden of the infection among individuals who visited the main Medical Centre in Tobruk region, eastern Libya, for various medical and surgical conditions. A research team interviewed public health officials in Tobruk Medical Center, inspected available equipment, and obtained data available for people who were positive for antibodies to HCV (anti-HCV) as part of their routine pre-invasive procedures and pre-donation screening tests from January 2005 to April 2020. HCV antibody tests were positive for 612 cases out of 368,392 (0.17%). Of those who tested positive for anti-HCV antibodies, no one had followed up by RNA test for identifying individuals with chronic HCV infection, and there are no links to outpatient care and treatment. Our findings highlight the critical need for an up-to-date HCV diagnosis and linkage to care guidelines, which includes a follow-up RNA test for anti-HCV positive patients and early linkage to care for confirmed cases to accelerate the elimination of HCV infection from the community. Full article