John Njeru

Dr. John Njeru

orcid

Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 August 2016 in BMC Public Health
Verified
Journal Article
Open access
PDF file
JNJohn Njeru
John Njeru
Gamal WarethGamal Wareth
Gamal Wareth
FMFalk Melzer
Falk Melzer
Klaus HenningKlaus Henning
Klaus Henning
Mathias W. PletzMathias W. Pletz
Mathias W. Pletz
HNHeinrich Neubauer
Heinrich Neubauer
Brucellosis is a debilitating zoonotic disease affecting humans and animals. A comprehensive, evidence-based assessment of literature and officially available data on animal and human brucellosis for Kenya are missing. The aim of the current review is to provide frequency estimates of brucellosis in humans, animals and risk factors for human infection, and help to understand the current situation in Kenya. A total of accessible 36 national and international publications on brucellosis from 1916 to 2016 were reviewed to estimate the frequency of brucellosis in humans and animals, and strength of associations between potential risk factors and seropositivity in humans in Kenya. The conducted studies revealed only few and fragmented evidence of the disease spatial and temporal distribution in an epidemiological context. Bacteriological evidence revealed the presence of Brucella (B.) abortus and B. melitensis in cattle and human patients, whilst B. suis was isolated from wild rodents only. Similar evidence for Brucella spp infection in small ruminants and other animal species is unavailable. The early and most recent serological studies revealed that animal brucellosis is widespread in all animal production systems. The animal infection pressure in these systems has remained strong due to mixing of large numbers of animals from different geographical regions, movement of livestock in search of pasture, communal sharing of grazing land, and the concentration of animals around water points. Human cases are more likely seen in groups occupationally or domestically exposed to livestock or practicing risky social-cultural activities such as consumption of raw blood and dairy products, and slaughtering of animals within the homesteads. Many brucellosis patients are misdiagnosed and probably mistreated due to lack of reliable laboratory diagnostic support resulting to adverse health outcomes of the patients and routine disease underreporting. We found no studies of disease incidence estimates or disease control efforts. The risk for re-emergence and transmission of brucellosis is evident as a result of the co-existence of animal husbandry activities and social-cultural activities that promote brucellosis transmission. Well-designed countrywide, evidence-based, and multidisciplinary studies of brucellosis at the human/livestock/wildlife interface are needed. These could help to generate reliable frequency and potential impact estimates, to identify Brucella reservoirs, and to propose control strategies of proven efficacy.

27 January 2017 in Current Clinical Microbiology Reports
Verified
Journal Article
Closed access
PDF file
TJTariq Jamil
Tariq Jamil
FMFalk Melzer
Falk Melzer
JNJohn Njeru
John Njeru
Hosny El-AdawyHosny El-Adawy
Hosny El-Adawy
HNHeinrich Neubauer
Heinrich Neubauer
Gamal WarethGamal Wareth
Gamal Wareth

1 September 2017 in New Microbes and New Infections
Verified
Journal Article
Open access
JNJohn Njeru
John Njeru
HTH. Tomaso
H. Tomaso
Katja Mertens-ScholzKatja Mertens-Scholz
Katja Mertens-Scholz
KHK. Henning
K. Henning
Gamal WarethGamal Wareth
Gamal Wareth
MPM.W. Pletz
M.W. Pletz
Tularaemia is a highly contagious infectious zoonosis caused by the bacterial agent Francisella tularensis. The aim of this study was to investigate the presence of antibodies to F. tularensis in febrile patients in northeastern Kenya. During 2014-2015, 730 patients were screened for anti-F. tularensis antibodies using a combination of ELISA and Western blot. Twenty-seven (3.7%) individuals were positive for F. tularensis. Tularaemia was not suspected by the treating clinicians in any of them. Our results suggest that tularaemia may be present in Kenya but remain unreported, and emphasizes the need for local clinicians to broaden their diagnostic repertoire when evaluating patients with undifferentiated febrile illness.

20 March 2023 in Antibiotics
Verified
Journal Article
Open access
PDF file
PMPatrick Muinde
Patrick Muinde
JMJohn Ndemi Maina
John Ndemi Maina
KMKelvin Momanyi
Kelvin Momanyi
VYVictor Yamo
Victor Yamo
JNJohn Njeru
John Njeru
JKJohn Kiiru
John Kiiru
There is increasing proof of bacterial resistance to antibiotics all over the world, and this puts the effectiveness of antimicrobials that have been essential in decreasing disease mortality and morbidity at stake. The WHO has labeled some classes of antimicrobials as vitally important to human health. Bacteria from animals are thought to be reservoirs of resistance genes that can be transferred to humans through the food chain. This study aimed to identify the resistance patterns of bacteria from pork and poultry meat samples purchased from leading retail outlets in Kenya. Of the 393 samples collected, 98.4% of pork and 96.6% of poultry were contaminated with high levels of bacteria. Among the 611 bacterial isolates recovered, 38.5% were multi-drug resistant. This resistance was noted for critically essential antimicrobials (according to the WHO) such as rifampicin (96%), ampicillin (35%), cefotaxime (9%), cefepime (6%), and ciprofloxacin (6%). Moreover, there was high resistance to key antimicrobials for veterinary medicine such as tetracycline (39%), sulfamethoxazole (33%), and trimethoprim (30%). It is essential to spread awareness about the judicious use of antibiotics and take preventive measures to reduce disease burden.

DODismas Oketch
Dismas Oketch
RNRuth Wanjiru Njoroge
Ruth Wanjiru Njoroge
INIsaac Ambogo Ngere
Isaac Ambogo Ngere
JGJohn Gachohi
John Gachohi
SWSamuel Waiguru
Samuel Waiguru
EOEric Osoro
Eric Osoro
Brucellosis remains a major zoonotic disease worldwide, with disproportionate burden in low- and middle-income countries where limited veterinary and healthcare infrastructure constrain effective control measures. However, its pathways of transmission are poorly understood. In pastoralist settings, we hypothesize that camels have a high burden of Brucella spp. and play a key role in spreading it to humans and other livestock. This manuscript presents a study protocol to quantify the relative contribution of various livestock species to brucellosis transmission and identify cost-effective control strategies in Kenya. Using probability-proportional-to-size sampling, we aimed to recruit a longitudinal cohort of 170 households and their herds per site in the Marsabit and Kajiado counties. Households rearing at least one livestock species (cattle, camels, goats, sheep) were eligible. Serum, milk, and vaginal swabs (from livestock), and serum (from humans) were collected for testing using Rose Bengal Test, ELISA, qPCR, and culture methods. Concurrently, surveillance for suspected brucellosis was conducted in study health facilities. A qualitative ethnographic study and livestock movement monitoring using GPS-collared animals were nested within the cohort. These data will be used to parameterize a multi-host, multi-species infectious disease model through Approximate Bayesian Computation. Through this One Health approach, our study will identify and optimize potential interventions and help inform the development of a comprehensive cost-effective national control program for brucellosis.

30 May 2025 in Global Health Action
Verified
Journal Article
Open access
IKIsaac Kisiangani
Isaac Kisiangani
ÂBÂngela Jornada Ben
Ângela Jornada Ben
EWElke Wynberg
Elke Wynberg
WWWelcome Wami
Welcome Wami
SISamuel Iddi
Samuel Iddi
CSConstance Schultsz
Constance Schultsz
Evidence on long COVID remains limited in sub-Saharan countries. This study explored the occurrence of COVID-19-related symptoms and factors affecting recovery and long COVID severity in Nairobi, Kenya. A prospective cohort of individuals testing positive for SARS-CoV-2 between February 2022 and February 2023 was followed until June 2023. COVID-19-related symptoms were assessed every three months. Time to recovery was analyzed using survival analysis, while factors affecting recovery factors and long COVID severity using Cox proportional hazard and Poisson regression, respectively. Among 291 participants (median age 34, 59.1% female), 42 (14%) had severe/critical infection. At 6 and 12 months post-positive PCR, 53.1% and 33.5% had ≥ 1 COVID-19-related symptoms, respectively. Fatigue (40.2%), pain (36.8%), sore throat (36.8%), headaches (36.4%), and loss of strength (31.6%) were most common. Median time to recovery was longer for severe/critical cases than mild/moderate (234 vs 206 days, p = 0.016). Participants aged 40-64 years experienced slower recovery than those aged < 40 years (aHR = 0.635 [95%CI, 0.429;0.941]). Participants with tertiary education recovered faster than those with primary education (aHR = 1.869 [95%CI, 1.050;3.327]). Long COVID severity was associated with female sex (aIRR = 1.418 [95%CI; 1.078;1.864]), tertiary education (aIRR, 0.489 [95%CI, 0.415;0.576]), and ≥ 1 comorbidity (aIRR = 2.415 [95%CI, 1.639;3.559]). Six months post-infection, half had lingering symptoms, with a third still affected after a year. Recovery was faster in younger, educated individuals, while severe long COVID was more common in women, those with low education and pre-existing conditions. The burden of long COVID in Kenya requires support for vulnerable groups.