Genomic evaluation of novel Kenyan virulent phage isolates infecting carbapenemase-producing Klebsiella pneumoniae and safety determination of their lysates in Balb/c mice.

This study aimed to evaluate the genomic features of novel Kenyan virulent phage isolates infecting carbapenemase-producing Klebsiella pneumoniae and to determine the safety of their lysates using mice model in a preclinical study. The genomics showed that the Klebsiella phages vB_KpM_CPRSA and vB_KpM_CPRSB belonged to the genus Slopekvirus with a similarity index of less than 92% compared to the most closest relative species. Their genomes did not contain antimicrobial resistance and toxin genes. Then endotoxin levels in the Klebsiella phage lysates were statistically significant (p value ˃ 0.05). The serum activities of aspartate aminotransferase, alanine aminotransferase and urea in the group of balb/c mice injected with bacteriophage lysates through the intravenous route were higher compared to that of the intranasal route. Unexpectedly, there was mild congestion of the central veins of kidneys and liver without damage to renal tubules and hepatocytes and a lack of physical discomfort and pain in the mice. Our study isolated and characterised Klebsiella phages against carbapenem-resistant K. pneumoniae, which are promising therapeutic agents for the treatment of respiratory tract infections using the topical mode of administration as the preferred route of bacteriophage delivery.

Evaluation of the detection of staA, viaB and sopE genes in Salmonella spp. using the polymerase chain reaction (PCR).

Typhoid fever is caused by the bacteria Salmonella enterica subspecies enterica serovar Typhi (S. Typhi) and remains a significant health problem in many developing countries. Lack of adequate diagnostic capabilities has contributed greatly in making typhoid fever endemic in these regions. Reliable and inexpensive diagnostic tests are needed to improve the management of this disease burden. We evaluated the ability of staA, viaB and sopE genes to detect and differentiate between the three most prevalent Salmonella spp. in Kenya (S. Typhi, S. Typhimurium and S. Enteritidis) using conventional polymerase chain reaction (PCR). The staA primers and viaB primers were found to be specific only for the different strains of S. Typhi, producing PCR products of 585 bp and 540 bp, respectively. The sopE primers was demonstrated to be specific for all Salmonella spp. producing a 465 bp PCR product with no amplification with E. coli and S. boydii bacterial strains.

Norovirus infections and knowledge, attitudes and practices in food safety among food handlers in an informal urban settlement, Kenya 2017.

INTRODUCTION: A leading cause of acute gastroenteritis, norovirus can be transmitted by infected food handlers but norovirus outbreaks are not routinely investigated in Kenya. We estimated norovirus prevalence and associated factors among food handlers in an informal urban settlement in Nairobi, Kenya. METHODS: We conducted a cross-sectional survey among food handlers using pretested questionnaires and collected stool specimens from food handlers which were analyzed for norovirus by conventional PCR. We observed practices that allow norovirus transmission and surveyed respondents on knowledge, attitudes, and practices in food safety. We calculated odd ratios (OR) with 95% confidence intervals (CI) to identify factors associated with norovirus infection. Variables with p < 0.05 were included in multivariate logistic regression analysis to calculate adjusted OR and 95% CI. RESULTS: Of samples from 283 respondents, 43 (15.2%) tested positive for norovirus. Factors associated with norovirus detection were: reporting diarrhea and vomiting within the previous month (AOR = 5.7, 95% CI = 1.2-27.4), not knowing aerosols from infected persons can contaminate food (AOR = 6.5, 95% CI = 1.1-37.5), not knowing that a dirty chopping board can contaminate food (AOR = 26.1, 95% CI = 1.6-416.7), observing respondents touching food bare-handed (AOR = 3.7, 95% CI = 1.5-11.1), and working in premises without hand washing services (AOR = 20, 95% CI = 3.4-100.0). CONCLUSION: The norovirus infection was prevalent amongst food handlers and factors associated with infection were based on knowledge and practices of food hygiene. We recommend increased hygiene training and introduce more routine inclusion of norovirus testing in outbreaks in Kenya.

Genomic characterization of four novel Staphylococcus myoviruses.

We report here the annotation of the complete genomes of four novel lytic Staphylococcus phages; Stab20, Stab21, Stab22 and Stab23. These phages have double-stranded DNA genomes ranging between 153,338 and 155,962 bp in size with terminal repeats of 10,814-12,304 bp. The genome analysis suggests that they represent new phage species within the genus Kayvirus in the subfamily Twortvirinae of the family Herelleviridae.

Nonsteroidal anti-inflammatory drugs for assisted reproductive technology.

BACKGROUND: Despite substantial improvements in the success of treatments through assisted reproduction technologies (ART), live birth rates remain constantly low, and practitioners are seeking aetiologic treatments to improve the outcomes.Local inflammatory response is believed to contribute to implantation failure, where prostaglandins may increase uterine contractions and decrease uterine receptivity, decreasing the possibility of an IVF cycle leading to successful embryo transfer. In this context, nonsteroidal anti-inflammatory drugs (NSAIDs) have been employed to inhibit the negative prostaglandin effect. They are often offered in clinical practice to improve ART outcomes, but current robust evidence on their efficacy is lacking. OBJECTIVES: To evaluate the effectiveness and safety of nonsteroidal anti-inflammatory drugs as co-treatments in infertile women undergoing assisted reproduction, in terms of improving live birth and miscarriage rates. SEARCH METHODS: We designed the search using standard Cochrane methods and performed it on databases from their inception to 20 February 2019.We searched the Cochrane Gynaecology and Fertility Group Specialised Register of controlled trials, CENTRAL via the Cochrane Central Register of Studies Online, MEDLINE, Embase, CINAHL, and the trial registers for ongoing and registered trials, grey literature and treatment guidelines. We handsearched reference lists of relevant systematic reviews and RCTs, and PubMed and Google for any recent trials. There were no restrictions by language or country of origin. SELECTION CRITERIA: All RCTs on the use of NSAIDs as co-treatment during an ART cycle compared with no use or the use of placebo or any other similar drug, along with the comparison of any NSAID to another. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures recommended by Cochrane. Our primary outcomes were live birth/ongoing pregnancy and miscarriage. We performed statistical analysis using Review Manager 5. We assessed evidence quality using GRADE methods. MAIN RESULTS: We found 11 RCTs (1884 women) suitable for inclusion in the review. Most studies were at unclear or high risk of bias. The main limitations in the overall quality of the evidence were high risk of bias, unexplained heterogeneity and serious imprecision and indirectness.There were no data on our primary outcome - live birth per woman randomised - in any review comparisons.NSAIDs vs. placebo/no treatmentWe are uncertain of an effect on ongoing pregnancy when NSAIDs were compared to placebo/no treatment (risk ratio (RR) 1.06, 95% confidence interval (CI) 0.71 to 1.59; 4 studies, 1159 participants; I² = 53%; very low quality evidence). Results suggest that if the chance of ongoing pregnancy following placebo or no treatment is assumed to be 15%, the chance following the use of NSAIDs is estimated to be between 12% and 24%. Subgroup analysis according to the type of NSAID yielded similar results.We are also uncertain of an effect on miscarriage rates when NSAIDs were compared to placebo/no treatment (RR 0.62, 95% CI 0.33 to 1.16; 4 studies, 525 participants; I² = 43%; very low quality evidence). Results suggest that if the chance of miscarriage following placebo or no treatment is assumed to be 21%, the chance following the use of NSAIDs is estimated to be between 7% and 27%. The results were similar when two studies were excluded due to high risk of bias.Concerning the secondary outcomes, we are uncertain of an effect on clinical pregnancy rates (RR 1.23, 95% CI 1.00 to 1.52; 6 studies, 1570 participants; I² = 49%; low-quality evidence); on ectopic pregnancy (RR 0.56, 95% CI 0.05 to 5.89; 1 study, 72 participants); on multiple pregnancy (RR 2.00, 95% CI 0.18 to 21.67; 1 study, 180 participants); and on side effects (RR 1.39, 95% CI 0.02 to 119.35; 3 studies, 418 participants; I² = 79%). The evidence suggests that if the chance of clinical pregnancy following placebo or no treatment is assumed to be 30%, the chance following the use of NSAIDs is estimated to be between 31% and 45%. If the chance of ectopic pregnancy following placebo or no treatment is assumed to be 5%, the chance following the use of NSAIDs is estimated to be between 0.3% and 31%. If the chance of multiple pregnancy following placebo or no treatment is assumed to be 1%, the chance following the use of NSAIDs is estimated to be between 0.2 % and 24%.There were no cases of congenital anomalies during antenatal ultrasound screening of the women in one study.NSAID vs. another NSAIDOnly one study compared piroxicam with indomethacin: we are uncertain of an effect on ongoing pregnancy (RR 1.12, 95% CI 0.63 to 2.00; 1 study, 170 participants; very low quality evidence); and on miscarriage (RR 1.00, 95% CI 0.44 to 2.28; 1 study, 170 participants; very low quality evidence). The evidence suggests that if the chance of ongoing pregnancy following indomethacin is assumed to be 20%, the chance following the use of piroxicam is estimated to be between 13% and 40%; while for miscarriage, the evidence suggests that if the chance following indomethacin is assumed to be 12%, the chance following the use of piroxicam is estimated to be between 5% and 27%.Similar results were reported for clinical pregnancy (RR 1.07, 95% CI 0.71 to 1.63; 1 study, 170 participants; very low quality evidence).There were no data for the other outcomes specified in this review.NSAID vs. aspirinNo study reported this comparison. AUTHORS' CONCLUSIONS: Currently we are uncertain of an effect of the routine use of NSAIDs as co-treatments in infertile women undergoing assisted reproduction in order to improve ongoing pregnancy and miscarriage rates. This is based on available data from RCTs, where very low quality evidence showed that there is no single outcome measure demonstrating a benefit with their use. Further large, well-designed randomised placebo-controlled trials reporting on live births are required to clarify the exact role of NSAIDs.

Impact of the Levonorgestrel-Releasing Intrauterine System on the Progression of Chlamydia trachomatis Infection to Pelvic Inflammatory Disease in a Baboon Model.

Background: Understanding the relationship between the levonorgestrel (LNG)-releasing intrauterine system (IUS) and sexually transmitted infections (STIs) is increasingly important as use of the LNG-IUS grows to include women at higher risk for STIs. This study assessed the impact of the LNG-IUS on development of Chlamydia trachomatis pelvic inflammatory disease, using a baboon model. Methods: Baboons with and those without the LNG-IUS were cervically inoculated with C. trachomatis and monitored daily, and cervical and fallopian tube swab specimens were collected weekly for C. trachomatis quantitation by nucleic acid amplification testing and culture. Vaginal swab specimens were collected for cytokine analysis, and serum samples were obtained for detection of C. trachomatis antibodies. Results: The LNG-IUS resulted in an increased C. trachomatis burden in the cervix, with the bacterial burden in the LNG-IUS group diverging from that in the non-LNG-IUS group by 6 weeks after infection. One of 7 baboons in the non-LNG-IUS group and 2 of 6 in the LNG-IUS group developed pelvic inflammatory disease, while 3 animals in each group met criteria suggestive of pelvic inflammatory disease. LNG-IUS increased baseline interleukin 8 levels but failed to further upregulate interleukin 8 during infection. In LNG-IUS recipients, early perturbations in the interleukin 1ß axis corresponded to decreased C. trachomatis clearance and increased T-helper type 2 immune responses. Conclusion: LNG-IUS use results in delayed clearance of C. trachomatis and might alter the reproductive tract immune environment.

Allogeneic ovarian transplantation using immunomodulator preimplantation factor (PIF) as monotherapy restored ovarian function in olive baboon.

PURPOSE: Allogeneic ovarian transplantation may be an alternative in the future to oocyte donation in women with premature ovarian failure. The objectives of this study were to (a) evaluate allotransplantation feasibility for restoration of ovarian function and (b) assess efficacy of synthetic preimplantation factor (PIF) monotherapy as sole immune-acceptance regimen. METHODS: This is an experimental animal study using non-human primates (Papio anubis). Allogeneic orthotopic ovarian tissue transplantation was performed in two female olive baboons. PIF was administered as a monotherapy to prevent immune rejection and achieve transplant maintenance and function. Subjects underwent bilateral oophorectomy followed by cross-transplantation of prepared ovarian cortex. Postoperatively, subjects were monitored for clinical and biochemical signs of graft rejection and return of function. Weekly blood samples were obtained to monitor graft acceptance and endocrine function restoration. RESULTS: Postoperatively, there were no clinical signs of rejection. Laboratory parameters (alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), creatinine) did not indicate organ rejection at any stage of the experiment. Initially, significant loss of follicles was noticed after grafting and serum follicle-stimulating hormone (FSH) and E2 levels were consistent with ovarian failure. Seven months after transplantation, one animal exhibited recurrence of ovarian endocrine function (perineal swelling, E2 rise, FSH decrease, and return of menstruation). CONCLUSIONS: Organ rejection after allogeneic ovarian transplantation was prevented using PIF as monotherapy for the first time and no side effects were recorded. The study suggests the clinical feasibility of ovarian allotransplantation to obtain ovarian function.

Prevalence and geographical distribution of Papio hamadryas papillomavirus 1 (PhPV1) in Kenyan baboons.

Papio hamadryas papillomavirus (PhPV) 1, 2, and 3, are Alphapapillomaviruses that have been detected in Kenyan Olive baboons but the distribution is unknown. Therefore, cervical screening for PhPV1 was performed in baboons from various areas in Kenya using a nested polymerase chain reaction. The prevalence rate was 33%.

Ovarian tissue cryopreservation by vitrification in olive baboons (papio anubis): a pilot study.

BACKGROUND: Ovarian tissue cryopreservation by vitrification is an attractive technique for fertility preservation in women. However, this technique has not been optimized. The aim of this study was to evaluate the baboon as a model for the preclinical study of ovarian tissue cryopreservation by vitrification and thawing. METHODS: Ovarian cortical tissues (1-mm cubes) were obtained surgically from adult female olive baboons (n = 9) maintained in captivity and vitrified using dimethyl sulphoxide and ethylene glycol protocol. The proportion of morphologically intact follicles (primordial, primary and secondary) in paired fresh and cryopreserved (vitrified-thawed) ovarian tissues was compared. RESULTS: Overall, 67.1% of follicles were morphologically normal after vitrification. When compared to fresh ovarian tissue, vitrified-thawed ovarian tissue contained a comparable number of intact primordial follicles (48.9 vs. 52.9%), and a lower number of both primary (14.8 vs. 29.5%; p < 0.05) and secondary (2.0 vs. 0.7%; p < 0.05) follicles. CONCLUSION: After vitrification and thawing, baboon ovarian tissue retains about 67% of morphologically normal follicles, which is comparable to results for human ovarian tissue, and suggests that the olive baboon is a promising animal model for preclinical assessment of ovarian vitrification, thawing and autotransplantation studies.

Short-term effects of high-dose khat on sperm parameters and reproductive hormonal levels in olive baboons (Papio anubis).

The biological effects of khat (Catha edulis) on reproduction and fertility are inadequately investigated and controversial, hence we determined the effects of oral administration of high-dose khat on sperm parameters and male hormonal levels in olive baboons. In this study, 6 male baboons received a high dose of khat (500 g/week) during 1 month. Electroejaculation for sperm studies (concentration, motility and chromatin integrity) and plasma collection for hormonal analysis (testosterone, prolactin and cortisol) were done weekly during 1 month before and 1 month during khat administration as well as 2 weeks after the last dose of khat administration. Administration of khat extract induced a significant reduction in sperm motility (p = 0.008), sperm count (p = 0.041), sperm chromatin integrity (p = 0.0003), testosterone levels (p = 0.035) and prolactin levels (p = 0.0115), but not in cortisol levels and sperm volume (p > 0.05). The results suggest that high-dose khat decreases sperm quality and testosterone and hence may contribute to male infertility.

Living with Endometriosis: A Narrative Analysis of the Experiences of Kenyan Women.

Despite the high global prevalence of endometriosis, little is known about the experiences of women living with the disease in low- and middle-income contexts, including in Kenya and other countries across sub-Saharan Africa. This study captures the perspectives and recommendations of Kenyan women living with endometriosis through written narratives about the impact of the disease on their daily lives and their journeys through diagnosis and treatment. Thirty-seven women between the ages of 22 and 48 were recruited from an endometriosis support group in Nairobi and Kiambu, Kenya (February-March of 2022) in partnership with the Endo Sisters East Africa Foundation. Narrative data (written anonymous stories submitted through Qualtrics) were analyzed using a deductive thematic analysis methodology. Their stories revealed three themes related to their shared experiences with endometriosis: (1) stigma and disruption to quality of life, (2) barriers to acceptable healthcare, and (3) reliance on self-efficacy and social support to cope with the disease. These findings demonstrate a clear need for improved social awareness of endometriosis in Kenya and the establishment of clear, effective, and supportive pathways, with trained, geographically and financially accessible health care providers, for endometriosis diagnosis and treatment.

Corrigendum: Formulation of phage cocktails and evaluation of their interaction with antibiotics in inhibiting carbapenemase-producing Klebsiella pneumoniae in vitro in Kenya.

[This corrects the article DOI: 10.4102/ajlm.v11i1.1803.].

Sustainable education and training in laboratory animal science and ethics in low- and middle-income countries in Africa - challenges, successes, and the way forward.

Despite the recognised need for education and training in laboratory animal science (LAS) and ethics in Africa, access to such opportunities has historically been limited. To address this, the Pan-African Network for Laboratory Animal Science and Ethics (PAN-LASE) was established to pioneer a support network for the development of education and training in LAS and ethics across the African continent.In the 4.5 years since the establishment of PAN-LASE, 3635 individuals from 28 African countries have participated in our educational activities. Returning to their home institutions, they have both established and strengthened institutional and regional hubs of knowledge and competence across the continent. Additionally, PAN-LASE supported the development of guidelines for establishment of institutional Animal Ethics Committees, a critical step in the implementation of ethical review processes across the continent, and in enhancing animal welfare and scientific research standards.Key challenges and opportunities for PAN-LASE going forward include the formalisation of the network; the sustainability of education and training programmes; implementation of effective hub-and-spoke models of educational provision; strengthening governance frameworks at institutional, national and regional levels; and the availability of Africa-centric open access educational resources.Our activities are enhancing animal welfare and the quality of animal research undertaken across Africa, enabling African researchers to undertake world-leading research to offer solutions to the challenges facing the continent. The challenges, successes and the lessons learnt from PAN-LASE's journey are applicable to other low- and middle-income countries across the world seeking to enhance animal welfare, research ethics and ethical review in their own country or region.

Novel Escherichia coli-Infecting Bacteriophages Isolated from Uganda That Target Human Clinical Isolates.

Background: The antimicrobial resistance catastrophe is a growing global health threat and predicted to be worse in developing countries. Phages for Global Health (PGH) is training scientists in these regions to isolate relevant therapeutic phages for pathogenic bacteria within their locality, and thus contributing to making phage technology universally available. Materials and Methods: During the inaugural PGH workshop in East Africa, samples from Ugandan municipal sewage facilities were collected and two novel Escherichia coli lytic phages were isolated and characterized. Results: The phages, UP19 (capsid diameter ∼100 nm, contractile tail ∼120/20 nm) and UP30 (capsid diameter ∼70 nm, noncontractile tail of ∼170/20 nm), lysed ∼82% and ∼36% of the 11 clinical isolates examined, respectively. The genomes of UP19 (171.402 kb, 282 CDS) and UP30 (49.834 kb, 75 CDS) closely match the genera Dhakavirus and Tunavirus, respectively. Conclusion: The phages isolated have therapeutic potential for further development against E. coli infections.

Baboon spermatology: basic assessment and reproducibility in olive baboons (Papio anubis).

BACKGROUND: Development of a reproducible baboon in vitro fertilization (IVF) system require optimized and reproducible sperm parameters. The objective of this study was to document basic spermatology values and investigate the reproducibility of these variables in the same baboons 1 or 3 months later in a larger number of baboons. METHODS: In this prospective study, sperm quality (semen volume, pH, concentration, motility, morphology and size) was evaluated in 27 sperm samples obtained from 9 baboons electroejaculated three times with a time interval of 1 month (between first and second sample collection) and 3 months (between second and third round sample collection). RESULTS: Baseline sperm values for semen volume (0.5 ± 0.3 ml), pH (7.5 ± 0.3), concentration (54.2 ± 19.3 million/ml), motility (67.3 ± 18.5%) and morphology (89.2 ± 4.8%) were similar to sperm samples obtained after 1 or 3 months (P > 0.05). Head, midpiece and tail abnormalities were rarely observed (0-9%). Sperm dimensions were characterized by a tail length of 69.6 ± 13.9 µm, a head width of 2.41 ± 0.43 µm and a head length of 3.49 ± 0.6 µm. CONCLUSION: Sperm quality was not affected by repeated electroejaculation with time intervals of 1 or 3 months, suggesting that the same baboon can participate multiple times in reproductive research.

Efficacy of diversely isolated lytic phages against multi-drug resistant Enterobacter cloacae isolates in Kenya.

Background: Enterobacter cloacae causes nosocomial infections in 15% of patients in low- and middle-income countries with emergence of carbapenem resistance. The utilisation of bacteriophages for therapeutic purposes is crucial for eradicating these resistant bacterial strains. Objective: This study evaluated the efficacy of lytic phages on bacterial isolates of E. cloacae and determined their stability in various physicochemical conditions. Methods: Twenty-nine lytic phages were isolated from the waste water of six informal settlements in Nairobi County, Kenya, from July 2019 to December 2020 and cross-reacted with 30 anonymised clinical isolates of E. cloacae. Six phages were then selected for physicochemical property studies. Phages were described as potent upon lysing any bacterial strain in the panel. Results: Selected phages were stable at 4 °C - 50 °C with a 5.1% decrease in titre in four of six phages and a 1.8% increase in titre in two of six phages at 50 °C. The phages were efficient following two weeks incubation at 4 °C with optimal activity at human body temperature (37 °C) and an optimal pH of 7.5. Phages were active at 0.002 M and 0.015 M concentrations of Ca2+ ions. The efficiency of all phages decreased with increased exposure to ultraviolet light. All phages (n = 29) showed cross-reactivity against anonymised clinical isolates of E. cloacae strains (n = 30). The most potent phage lysed 67.0% of bacterial strains; the least potent phage lysed 27.0%. Conclusion: This study reveals the existence of therapeutic phages in Kenya that are potent enough for treatment of multi-drug resistant E. cloacae.

An irreversible inhibitor of 17ß-hydroxysteroid dehydrogenase type 1 inhibits estradiol synthesis in human endometriosis lesions and induces regression of the non-human primate endometriosis.

Endometriosis is a gynecological disorder affecting about 10% of women and can lead to invalidating painful symptoms and infertility. Since there is no current definitive cure for this disease, new therapeutic options are necessary. 17ß-Hydroxysteroid dehydrogenase type 1 (17ß-HSD1) is involved in the production of estradiol (E2), the most potent estrogen in women, and of 5-androstene-3ß,17ß-diol (5-diol), a weaker estrogen than E2, but whose importance increases after menopause. 17ß-HSD1 is therefore a pharmacological target of choice for the treatment of estrogen-dependent diseases such as endometriosis. We developed a targeted-covalent (irreversible) and non-estrogenic inhibitor of 17ß-HSD1, a molecule named PBRM, and herein evaluated its efficiency for the treatment of endometriosis. In a cell-free assay containing estrone (E1), the natural substrate of 17ß-HSD1, PBRM was able to block the formation of E2 in a collection of 50 human endometriosis lesions from a different clinical feature type, location, and phase. When given orally by gavage at 15 mg/kg to baboons, the resulting plasmatic concentration of PBRM was found to be sufficiently high (up to 125 ng/mL) for an efficacy study in a non-human primate (baboon) endometriosis model. After 2 months of treatment, the number of lesions/adhesions decreased in 60% of animals (3/5) in the PBRM-treated group, compared to the placebo group which showed an increase in the number of lesion/adhesions in 60% (3/5) of animals. Indeed, the total number of lesions/adhesions decreased in treated group (-6.5 or -19% when excluding one animal) while it increased in the control group receiving a placebo (+11%). Analysis of specific endometriotic lesions revealed that PBRM decreased the number of red lesions (-67%; 8/12) and white lesions (-35%; 11/31), but not of blue-black lesions. Similarly, PBRM decreased the surface area of dense adhesions and filmy adhesions, as compared to placebo. Also, PBRM treatment did not significantly affect the number of menstrual days. Finally, this targeted covalent inhibitor showed no adverse effects and no apparent toxicity for the duration of the treatment. These data indicate that 17ß-HSD1 inhibitor PBRM is a promising candidate for therapy targeting endometriosis and supports the need of additional efforts toward clinical trials.

Formulation of phage cocktails and evaluation of their interaction with antibiotics in inhibiting carbapenemase-producing Klebsiella pneumoniae in vitro in Kenya.

Background: The development of alternative control measures, such as phage therapy or adjunctive therapy, is urgently needed to manage the dissemination of carbapenemase-producing Klebsiella pneumoniae. Objective: This study aimed to evaluate the therapeutic potential of formulated phage cocktails and their interaction with select antibiotics in inhibiting the growth of carbapenemase-producing K. pneumoniae clinical isolate in vitro in Kenya. Methods: The study was conducted from February 2021 to October 2021 at the Institute of Primate Research, Nairobi, Kenya. Phage cocktails were formulated based on the morphology and biological properties of precipitated Klebsiella phages. The efficacy of individual bacteriophages and phage cocktails as well as their combination with antibiotics were determined for their inhibitory activity on carbapenemase-producing K. pneumoniae (KP20). Results: The precipitated bacteriophages were members of Myoviridae, Siphoviridae and Podoviridae. Regarding the evaluation of the phage cocktails, the absorbances at 600 nm of the bacterial culture treated with the two-phage cocktail (2φ MA) ranged from 0.173 to 0.246 at 16 h and 20 h whereas it peaked from 2.116 to 2.190 for the positive control. Moreover, the results of the adjunctive therapy showed that the optical density at 600 nm of the bacterial culture treated with 2φ MA was 0.186 at 24 h post-incubation time while it was 0.099 with the bacterial culture treated with imipenem in combination with 2φ MA. Conclusion: This study demonstrated that the two-phage cocktail in combination with imipenem was able to synergistically delay the increase in carbapenemase-producing K. pneumoniae growth in vitro.

Cyclospora papionis, Cryptosporidium hominis, and human-pathogenic Enterocytozoon bieneusi in captive baboons in Kenya.

Cyclospora papionis, Cryptosporidium hominis, and Enterocytozoon bieneusi were detected in 42 (17.9%), 6 (2.6%), and 29 (12.3%) of 235 newly captured baboons in Kenya, respectively. Most C. hominis subtypes and E. bieneusi genotypes found have been detected in humans in the area, suggesting that cross-species transmission of cryptosporidiosis and microsporidiosis is possible.

Successful experimental infant baboon model for childhood cryptosporidiosis studies.

BACKGROUND: Cryptosporidiosis causes high morbidity and mortality in children under 2 years of age globally. The lack of an appropriate animal model that mimics the pathogenesis of disease in humans has hampered the development and testing of potential therapeutic options. This study aimed to develop and validate an infant baboon infection model of cryptosporidiosis. METHODS: Eighteen immunocompetent weaned infant baboons aged 12 to 16 months were used. The animals were n = 3 controls and three experimental groups of n = 5 animals each inoculated with Cryptosporidium parvum oocysts as follows: group 1: 2 × 104, group 2: 2 × 105, group 3: 2 × 106 followed by daily fecal sampling for oocyst evaluation. Blood sampling for immunological assay was done on the day of infection and weekly thereafter until the end of the experiment, followed by necropsy and histopathology. Statistical analysis was performed using R, SPSS, and GraphPad Prism software. Analysis of variance (ANOVA) and Bonferroni post hoc tests were used for comparison of the means, with p < 0.05 considered as a significant difference. Correlation coefficient and probit analysis were also performed. RESULTS: In all experimental animals but not controls, the onset of oocyst shedding occurred between days 2 and 4, with the highest oocyst shedding occurring between days 6 and 28. Histological analysis revealed parasite establishment only in infected animals. Levels of cytokines (TNF-α, IFN-γ, and IL-10) increased significantly in experimental groups compared to controls. CONCLUSION: For developing a reproducible infant baboon model, 2 × 104 oocysts were an effective minimum quantifiable experimental infection dose.