Frequency and diversity of carbapenemase-producing Enterobacterales recovered from untreated wastewater impacted by selective media containing cefotaxime and meropenem in Ohio, USA.

As safe agents of last resort, carbapenems are reserved for the treatment of infections caused by multidrug-resistant organisms. The impact of ß-lactam antibiotics, cefotaxime, and meropenem on the frequency and diversity of carbapenemase-producing organisms recovered from environmental samples has not been fully established. Therefore, this methodological study aimed at determining ß-lactam drugs used in selective enrichment and their impact on the recovery of carbapenemase-producing Enterobacterales (CPE) from untreated wastewater. We used a longitudinal study design where 1L wastewater samples were collected weekly from wastewater treatment plant (WWTP) influent and quarterly from contributing sanitary sewers in Columbus, Ohio USA with 52 total samples collected. Aliquots of 500 mL were passed through membrane filters of decreasing pore sizes to enable all the water to pass through and capture bacteria. For each sample, the resulting filters were placed into two modified MacConkey (MAC) broths, one supplemented with 0.5 µg/mL of meropenem and 70 µg/mL of ZnSO4 and the other supplemented with 2 µg/mL cefotaxime. The inoculated broth was then incubated at 37° C overnight, after which they were streaked onto two types of correspondingly-modified MAC agar plates supplemented with 0.5 µg/mL and 1.0 µg/mL of meropenem and 70 µg/mL of ZnSO4 and incubated at 37°C overnight. The isolates were identified based on morphological and biochemical characteristics. Then, up to four distinct colonies of each isolate's pure culture per sample were tested for carbapenemase production using the Carba-NP test. Matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS) MALDI-TOF MS was used to identify carbapenemase-producing organisms. In total 391 Carba-NP positive isolates were recovered from the 52 wastewater samples: 305 (78%) isolates had blaKPC, 73 (19%) carried blaNDM, and 14 (4%) harbored both blaKPC and blaNDM resistance genes. CPE genes of both blaKPC and blaNDM were recovered in both types of modified MAC broths, with 84 (21%) having a blaKPC gene, 22 (6%) carrying blaNDM and 9 (2%) harbored both a blaKPC and blaNDM of isolates recovered from MAC medium incorporated with 0.5ug/mL meropenem and 70ug/mL ZnSO4. The most prevalent isolates were Klebsiella pneumoniae, Escherichia coli, and Citrobacter spp.

Characteristics of Staphylococcus aureus Isolated from Patients in Busia County Referral Hospital, Kenya.

Staphylococcus aureus is an important pathogen associated with hospital, community, and livestock-acquired infections, with the ability to develop resistance to antibiotics. Nasal carriage by hospital inpatients is a risk for opportunistic infections. Antibiotic susceptibility patterns, virulence genes and genetic population structure of S. aureus nasal isolates, from inpatients at Busia County Referral Hospital (BCRH) were analyzed. A total of 263 inpatients were randomly sampled, from May to July 2015. The majority of inpatients (85.9%) were treated empirically with antimicrobials, including ceftriaxone (65.8%) and metronidazole (49.8%). Thirty S. aureus isolates were cultured from 29 inpatients with a prevalence of 11% (10.3% methicillin-susceptible S. aureus (MSSA), 0.8% methicillin resistant S. aureus (MRSA)). Phenotypic and genotypic resistance was highest to penicillin-G (96.8%), trimethoprim (73.3%), and tetracycline (13.3%) with 20% of isolates classified as multidrug resistant. Virulence genes, Panton-Valentine leukocidin (pvl), toxic shock syndrome toxin-1 (tsst-1), and sasX gene were detected in 16.7%, 23.3% and 3.3% of isolates. Phylogenetic analysis showed 4 predominant clonal complexes CC152, CC8, CC80, and CC508. This study has identified that inpatients of BCRH were carriers of S. aureus harbouring virulence genes and resistance to a range of antibiotics. This may indicate a public health risk to other patients and the community.

Epidemiological study on foot-and-mouth disease in small ruminants: Sero-prevalence and risk factor assessment in Kenya.

Foot-and-mouth disease (FMD) is endemic in Kenya affecting cloven-hoofed ruminants. The epidemiology of the disease in small ruminants (SR) in Kenya is not documented. We carried out a cross-sectional study, the first in Kenya, to estimate the sero-prevalence of FMD in SR and the associated risk factors nationally. Selection of animals to be sampled used a multistage cluster sampling approach. Serum samples totaling 7564 were screened for FMD antibodies of non-structural-proteins using ID Screen® NSP Competition ELISA kit. To identify the risk factors, generalized linear mixed effects (GLMM) logistic regression analysis with county and villages as random effect variables was used. The country animal level sero-prevalence was 22.5% (95% CI: 22.3%-24.3%) while herd level sero-prevalence was 77.6% (95% CI: 73.9%-80.9%). The risk factor that was significantly positively associated with FMD sero-positivity in SR was multipurpose production type (OR = 1.307; p = 0.042). The risk factors that were significantly negatively associated with FMD sero-positivity were male sex (OR = 0.796; p = 0.007), young age (OR = 0.470; p = 0.010), and sedentary production zone (OR = 0.324; p<0.001). There were no statistically significant intra class correlations among the random effect variables but interactions between age and sex variables among the studied animals were statistically significant (p = 0.019). This study showed that there may be widespread undetected virus circulation in SR indicated by the near ubiquitous spatial distribution of significant FMD sero-positivity in the country. Strengthening of risk-based FMD surveillance in small ruminants is recommended. Adjustment of husbandry practices to control FMD in SR and in-contact species is suggested. Cross-transmission of FMD and more risk factors need to be researched.

Antimicrobial Resistance Profiles and Genes of Staphylococci Isolated from Mastitic Cow's Milk in Kenya.

Increasing numbers of potentially zoonotic multidrug-resistant (MDR) staphylococci strains, associated with mastitis in dairy cows, are being reported globally and threaten disease management in both animal and human health. However, the prevalence and antimicrobial resistance profiles of these strains, including methicillin-resistant staphylococci (MRS), in Kenya is not well known. This study investigated the drug resistance profiles and genes carried by 183 staphylococci isolates from 142 dairy cows representing 93 farms recovered from mastitis milk of dairy cows in two selected counties in Kenya. Staphylococci isolates were characterized by phenotypic characteristics, polymerase chain reaction (PCR) amplification, partial sequencing and susceptibility testing for 10 antimicrobial drugs. Detection of seven resistance genes to the various antimicrobial drugs was conducted using PCR. Overall, phenotypic resistance among the staphylococci ranged between 66.1% for ampicillin and 3.5% for fluoroquinolones. Twenty-five percent (25%) of S. aureus and 10.8% of the coagulase-negative staphylococci (CoNS) isolates, were methicillin-resistant staphylococci phenotypically (defined as resistance to cefoxitin disk diffusion). The most common genes found in S. aureus and CoNS were blaZ and strB at 44.3% and 26%, and 78% and 50%, respectively. MDR was observed in 29.67% and 16.3% of S. aureus and CoNS, respectively. These findings pose a threat to bovine mastitis treatment and management as well as human health.

Prevalence, Etiology, and Risk Factors of Mastitis in Dairy Cattle in Embu and Kajiado Counties, Kenya.

Bovine mastitis continues to be a leading cause of heavy economic losses in the dairy industry and a public health hazard globally. This cross-sectional study investigated the prevalence, etiologies of clinical and subclinical mastitis, and associated predisposing factors in Embu and Kajiado counties in Kenya. A semistructured questionnaire was administered to 154 smallholder dairy farmers to collect data on management practices, animal factors, and disease history. A total of 395 dairy cows were initially screened for subclinical mastitis using the California mastitis test (CMT), and milk samples were aseptically collected. Both CMT positive and CMT negative samples were analyzed using conventional bacteriological isolation and identification procedures. In the present study, the overall prevalence of mastitis based on CMT and clinical examination was 80% (316/395), out of which 6.8% (27/395) was clinical mastitis, while 73.1% (289/395) was subclinical mastitis. Based on culture, the overall prevalence of clinical and subclinical mastitis was 51.6% (815/1580), 74.4% (294/395), and 76.6% (118/154) at the quarter, cow, and farm level, respectively. From the 1574 milk samples analyzed by cultured, 1016 bacteria were yielded. The predominant bacteria were coagulase-negative Staphylococcus (CNS), 42.8% (435/1016), and in decreasing order, Streptococcus species, 22.2% (226/1016), Staphylococcus aureus, 15.7% (160/1016), and Pseudomonas aeruginosa, 5.1% (52/1016), and the least was Enterobacter species, 0.7% (7/1016), while 23.7% of the sample yielded no bacterial growth. Risk factor analysis revealed that milking mastitic cows last (p=0.002), using a clean udder drying towel for each cow (p=0.033) and previous history of mastitis (p=0.046) were significantly associated with presence of mastitis. The current study has shown a relatively high prevalence of subclinical mastitis with CNS as predominant bacteria. Therefore, control measures are urgently warranted. Management factors such as milking mastitic cows last, using a clean towel for udder drying for each cow, and culling mastitic cows should be considered and included in the Kenyan mastitis control programs.

Seroprevalence and Risk Factors for Hepatitis B Virus Infection in Adolescent Blood Donors within Selected Counties of Western Kenya.

Hepatitis B virus is a widespread public health menace approximated to have infected 257 million people chronically by 2015. Data on the prevalence of HBV is important in formulating public health policies on HBV control like safe blood transfusion. Adolescents aged 15 to 24 years, known to engage in risky activities associated with HBV spread, constitute major blood donors in Kenya. Notwithstanding current blood donation safety measures, HBV still remain hazardous transfusion-transmissible infections in donated blood. This study therefore was to determine the prevalence of HBsAg and related risk factors among this donor group. A cross-sectional study was conducted from April 2019 to August 2019 in Siaya, Kisumu, and Homa Bay counties. One thousand (1000) voluntary blood donors 18 to 25 years old were recruited. A predonation questionnaire was used to record their sociodemographic features and prior risk exposures. Blood samples were initially tested for HBsAg using Murex HBsAg Version 3 (DiaSorin, UK) and positives confirmed using ARCHITECT HBsAg Qualitative Confirmatory assay (Abbott Ireland) as per the manufacturer's instructions. A result was considered positive if the first and confirmatory tests were all reactive. Generally, the prevalence of HBV was 3.4%, with no significant association between various sociodemographic variables and HBsAg positivity. Nevertheless, scarification and risky sexual behavior were significantly linked to HBV infections (odds ratio (OR) = 8.533, 95%confidence interval (CI) = 3.128-23.275, p value of 0.001 and OR = 5.471, 95%CI = 1.925-15.547, p value of 0.002, respectively). This study revealed a prevalence of 3.4% HBsAg among adolescent blood donors, with perilous sexual behaviors being the most significant risk factor, evidence that sexual contact still plays a major role in transmission of HBV among this donor group despite blood transfusion safety measures put in place. These study findings should therefore be put into consideration while framing health policies to mitigate effects of HBV infection on safe blood transfusion.

Prevalence of bovine and avian tuberculosis in camel herds and associated public health risk factors in Isiolo County, Kenya.

A cross-sectional study was conducted among 308 lactating camels selected from 15 herds from three different camel milk clusters in Isiolo County, Kenya, to determine prevalence of bovine and avian tuberculosis using Single Comparative Intradermal Tuberculin Skin test. Seventy-five (75) questionnaires were administered to pastoralists/herders, and focus group discussions were conducted among 3-5 pastoralists/herders selected from each camel herd to collect information on camel husbandry and health management practices and knowledge on tuberculosis in livestock and wildlife. An overall prevalence of bovine and avian reactors was 3.57 and 18.18%, respectively, with bovine and avian reactors for different clusters being 2.38, 3.82, and 4.48% and 25, 17.2, and 11.94%, respectively. There was significant difference (p < 0.05) in prevalence of bovine and avian reactors between different clusters. There was a negative correction (r = -0.1399) between herd size and bovine reactors, while there was a positive correlation (r = 0.0445) between herd size and avian reactors. The respondents indicated that camel herds are exposed to several risk factors like close contact with other herds or livestock or wildlife during grazing and at watering points. Pastoralists have poor knowledge on mode of infection and transmission of bovine or avian tuberculosis. The high prevalence of bovine and avian reactors and pastoralists' poor knowledge on mode of transmission signify potential risk to public health.

Sero-epidemiology of Peste des petits ruminants virus infection in Turkana County, Kenya.

BACKGROUND: Peste des petits ruminants (PPR) is a contagious viral disease of small ruminants. Serum samples from sheep (n = 431) and goats (n = 538) of all ages were collected in a cross-sectional study in Turkana County, Kenya. The objective was to estimate the sero-prevalence of PPR virus (PPRV) infection and associated risk factors in both species. PPRV competitive enzyme-linked immuno-sorbent assay (c-ELISA) analysed the presence of antibodies in the samples. All analyses were conducted for each species separately. Multivariable logistic regression models were fitted to the data to assess the relationship between the risk factors and PPRV sero-positivity. Mixed-effect models using an administrative sub-location as a random effect were also fitted to adjust for possible clustering of PPRV sero-positivity. Intra-cluster correlation coefficients (ρ) that described the degree of similarity among sero-positive responses for each species in each of the six administrative divisions were estimated. RESULTS: Goats had a significantly higher sero-prevalence of 40% [95% confidence interval (CI): 36%, 44%] compared to sheep with 32% [95% CI: 27%, 36%] (P = 0.008). Combined sero-prevalence estimates were heterogeneous across administrative divisions (n = 6) (range 22% to 65%) and even more across sub-locations (n = 46) (range 0% to 78%). Assuming that PPRV antibodies are protective of infection, a large pool of PPRV susceptible middle age group (>6 months and < 24 months) in both species was estimated. This was based on the low sero-prevalence in this group in goats (14% [95% CI: 10%, 20%]) and in sheep (18% [95% CI: 13%, 25%]). Regression analysis returned significant risk factors across species: in sheep - vaccination status, age and administrative division; in goats - sex, age, administrative division and sex*age interaction. The intra-sub-location correlation coefficients varied widely across divisions (range <0.001 to 0.42) and across species within divisions. CONCLUSIONS: Biological, spatial and socio-ecological factors are hypothesized as possible explanations for variation in PPRV sero-positivity in the Turkana pastoral ecosystem.

First Complete Genome Sequence of a Lineage III Peste des Petits Ruminants Virus.

We report the first complete genome sequence of a lineage III peste des petits ruminants virus (KN5/2011) using RNA extracted from goat lung tissue collected in Kenya in 2011. The genome shows the highest nucleotide sequence identity with lineage II peste des petits ruminants viruses (PPRVs) (86.1 to 87.2%) and the lowest with lineage IV PPRVs (82.5 to 83.8%).

Epidemiological investigation into the introduction and factors for spread of Peste des Petits Ruminants, southern Tanzania.

A study was carried out to confirm and identify sources and elucidate factors associated with the introduction of Peste des Petits Ruminants (PPR) in southern Tanzania. This study was conducted in Tandahimba and Newala districts of Mtwara region following suspected outbreak of PPR in the area. Qualitative data were collected using semi-structured questionnaires and in-depth interviews of key informants who included goat and sheep owners with suspected cases of PPR and animal health service providers as well as local administrative authority. Additionally, 216 serum samples and 28 swabs were collected for serological and virological laboratory disease confirmation. The results show that PPR was first introduced in Likuna village of Newala district in February 2009 through newly purchased goats from the Pugu livestock market located about 700 km in the outskirts of Dar es Salaam city. Factors which contributed to spread of PPR included communal grazing and the cheap prices of sick animals bought by livestock keepers for slaughtering in other villages. Laboratory findings confirmed presence of PPR in the area by RT-PCR and serological analysis revealed that seroprevalence was 31%. These findings have confirmed, for the first time, introduction of PPR in southern Tanzania. The presence of PPR poses high risk of southward spread of the disease to other southern African countries in the SADC region thus calling for concerted and collaborative efforts in prevention and control of the disease to avoid losses. Further elaborate studies on the spread, prevalence and risk factors associated with the disease should urgently be investigated.