Development of a bio-inkjet printed LAMP test kit for detecting human African trypanosomiasis.

Human African trypanosomiasis (HAT) is one of the neglected tropical diseases in sub-Saharan Africa. Early diagnosis and treatment prior to disease progression are crucial for the survival of HAT patients. We had previously established a loop-mediated isothermal amplification (LAMP) method for HAT diagnosis in which the reagents were dried for field-use purposes. In this study, we used a semi-automated process to produce the test tubes using a bio-inkjet printer to achieve an accurate production. The performance of the inkjet printer-produced dried LAMP test (CZC-LAMP) was found to be stable after storage for up to 180 days at 30 °C. The diagnostic accuracy of CZC-LAMP HAT was evaluated using DNA samples that were extracted from 116 Trypanosoma brucei gambiense patients and 66 T. b. rhodesiense patients. The sensitivity was 72% for T. b. gambiense (95%CI: 63%-80%) and 80% for T. b. rhodesiense (95%CI: 69%-89%). The specificity determined using DNA from 116 endemic control DNA samples was 95% (95%CI: 89%-98%). The performance of the CZC-LAMP HAT and CZC-LAMP rHAT were also evaluated using 14 crude blood lysate samples obtained from T. b. rhodesiense patients and endemic control samples collected from Rumphi District in Malawi. The sensitivity and specificity were both 100% (95%CI: 77%-100%). As the developed CZC-LAMP test does not require a cold chain or a sophisticated laboratory, it holds promise for use as a routine simple molecular tool for point-of-care HAT diagnosis in endemic areas.

Molecular characterization of Cryptosporidium spp. from patients with diarrhoea in Lusaka, Zambia.

Cryptosporidium is a major etiological agent of diarrhoeal diseases among children and immune-compromised individuals in sub-Saharan African countries. We conducted a study to determine the prevalence and genetic characteristics of Cryptosporidium spp. in stool samples from patients with diarrhoea who presented at the University Teaching Hospital in Lusaka, Zambia. Cryptosporidium species and subtypes from 71 microscopically confirmed cryptosporidiosis stool samples collected between 2017 and 2019 were determined by polymerase chain reaction followed by partial sequencing of the small subunit rRNA and 60-kDa glycoprotein (gp60) gene. Additionally, data for the period between 2014 and 2019 were reviewed and analysed for cryptosporidiosis seasonal and age distribution. Cryptosporidium was more prevalent in the rainy season. The highest number of cases was reported among the 1-4 year age group. By sequence analysis of the 71 positive isolates, Cryptosporidium hominis (n = 42; 59.2%), C. parvum (n = 27; 38%), C. felis (n = 1; 1.4%), and C. meleagridis (n = 1; 1.4%) were identified. Four C. hominis subtype families (Ia, Ib, Id, and Ie) and three C. parvum subtype families (IIc, IIe, and IIs) were identified. The most frequent subtypes were IeA11G3T3 (n = 20; 28.2%), IIcA5G3 (n = 12; 16.9%), IIeA12G1 (n = 11; 15.5%) and IaA30R3 (n = 10; 14.1%). The observed species/subtypes of C. hominis and C. parvum indicated that the infection was mainly transmitted through the anthroponotic route. The identification of C. felis and C. meleagridis suggests that an atypical zoonotic transmission cycle also exists.

TITLE: Caractérisation moléculaire de Cryptosporidium spp. de patients souffrant de diarrhée à Lusaka, Zambie. ABSTRACT: Cryptosporidium est un agent étiologique majeur des maladies diarrhéiques chez les enfants et les personnes immunodéprimées dans les pays d'Afrique subsaharienne. Nous avons mené une étude pour déterminer la prévalence et les caractéristiques génétiques de Cryptosporidium spp. dans des échantillons de selles de patients souffrant de diarrhée qui se sont présentés à l'hôpital universitaire de Lusaka, en Zambie. Les espèces et sous-types de Cryptosporidium provenant de 71 échantillons de selles de cryptosporidiose, confirmés au microscope et prélevés entre 2017 et 2019, ont été déterminés par réaction en chaîne par polymérase suivie d'un séquençage partiel de la petite sous-unité de l'ARNr et du gène de la glycoprotéine de 60 kDa (gp60). De plus, les données pour la période entre 2014 et 2019 ont été examinées et analysées pour la distribution saisonnière et par âge de la cryptosporidiose. Cryptosporidium était plus répandu pendant la saison des pluies. Le plus grand nombre de cas a été signalé dans le groupe d'âge de 1 à 4 ans. Par analyse séquentielle des 71 isolats positifs, Cryptosporidium hominis (n = 42 ; 59,2 %), C. parvum (n = 27 ; 38 %), C. felis (n = 1 ; 1,4 %) et C. meleagridis (n = 1 ; 1,4 %) ont été identifiés. Quatre familles de sous-types de C. hominis (Ia, Ib, Id et Ie) et trois familles de sous-types de C. parvum (IIc, IIe et IIs) ont été identifiées. Les sous-types les plus fréquents étaient A11G3T3 (n = 20 ; 28,2 %), IIcA5G3 (n = 12 ; 16,9 %), IIeA12G1 (n = 11 ; 15,5 %) et IaA30R3 (n = 10 ; 14,1 %). Les espèces/sous-types observés de C. hominis et C. parvum indiquent que l'infection est principalement transmise par voie anthroponotique. L'identification de C. felis et C. meleagridis suggère qu'il existe également un cycle de transmission zoonotique atypique.

Escherichia coli Antimicrobial Susceptibility Reduction amongst HIV-Infected Individuals at the University Teaching Hospital, Lusaka, Zambia.

Increased antimicrobial resistance among Human Immunodeficiency Virus (HIV)-infected individuals to commonly used antibiotics in the treatment of gastroenteritis is a public health concern, especially in resource-limited settings. We set out to compare the antimicrobial susceptibility pattern of Escherichia coli (E. coli) isolates from HIV-infected and HIV-uninfected individuals at a tertiary hospital in Lusaka, Zambia. An analytical cross-sectional study was conducted at the University Teaching Hospital from May 2019 to August 2019. Stool samples were screened, and 79 HIV-infected individuals matched by age and sex with 84 HIV-uninfected individuals that presented with E. coli associated gastroenteritis were studied. Demographics were collected from the Laboratory Information System (LIS) and stool samples were collected in a sterile leak-proof container. Samples were cultured and only those where E. coli was isolated were included in the study and tested for antimicrobial susceptibility by the Kirby-Bauer disk diffusion technique. HIV-positive individuals were 3 times (adjusted odds ratio (AOR) = 3.17; 95% CI (1.51, 6.66); p < 0.001) more likely to be resistant to quinolones compared with their HIV-negative counterparts. Similarly, HIV-positive individuals were almost 4 times (AOR = 3.97, 95% CI (1.37, 11.46); p = 0.011) more likely to have multidrug-resistant E. coli compared with those who were HIV-negative. HIV infection was associated with reduced E. coli susceptibility to commonly used antibiotics, and most cases showed resistance.