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1.
Clin Infect Dis ; 73(3): e569-e579, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-33044509

RESUMO

BACKGROUND: Shigella is a leading cause of childhood diarrhea and target for vaccine development. Microbiologic and clinical case definitions are needed for pediatric field vaccine efficacy trials. METHODS: We compared characteristics of moderate to severe diarrhea (MSD) cases in the Global Enteric Multicenter Study (GEMS) between children with culture positive Shigella to those with culture-negative, quantitative polymerase chain reaction (qPCR)-attributable Shigella (defined by an ipaH gene cycle threshold <27.9). Among Shigella MSD cases, we determined risk factors for death and derived a clinical severity score. RESULTS: Compared to culture-positive Shigella MSD cases (n = 745), culture-negative/qPCR-attributable Shigella cases (n = 852) were more likely to be under 12 months, stunted, have a longer duration of diarrhea, and less likely to have high stool frequency or a fever. There was no difference in dehydration, hospitalization, or severe classification from a modified Vesikari score. Twenty-two (1.8%) Shigella MSD cases died within the 14-days after presentation to health facilities, and 59.1% of these deaths were in culture-negative cases. Age <12 months, diarrhea duration prior to presentation, vomiting, stunting, wasting, and hospitalization were associated with mortality. A model-derived score assigned points for dehydration, hospital admission, and longer diarrhea duration but was not significantly better at predicting 14-day mortality than a modified Vesikari score. CONCLUSIONS: A composite severity score consistent with severe disease or dysentery may be a pragmatic clinical endpoint for severe shigellosis in vaccine trials. Reliance on culture for microbiologic confirmation may miss a substantial number of Shigella cases but is currently required to measure serotype specific immunity.


Assuntos
Disenteria Bacilar , Shigella , Vacinas , Estudos de Casos e Controles , Criança , Diarreia/epidemiologia , Disenteria Bacilar/diagnóstico , Disenteria Bacilar/epidemiologia , Humanos , Lactente , Reação em Cadeia da Polimerase , Shigella/genética
2.
BMC Pregnancy Childbirth ; 19(1): 339, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31533640

RESUMO

BACKGROUND: There is broad agreement that antenatal care (ANC) interventions, skilled attendance at birth and management of complications arising after delivery are key strategies that can tackle the high burden of maternal mortality in sub-Saharan Africa. In Kenya, utilisation rate of these services has remained low despite a government policy on free maternal care. The present study sought to understand what factors are leading to the low healthcare seeking during pregnancy, child birth and postnatal period in Siaya County in Kenya. METHODS: Six Focus Group Discussions were conducted with 50 women attending ANC in 6 public primary healthcare facilities. Participants were drawn from a sample of 200 women who were eligible participants in a Conditional Cash Transfer project aimed at increasing utilization of healthcare services during pregnancy and postnatal period. Interviews were conducted at the health facilities, recorded, transcribed and analysed using thematic analysis. RESULTS: Multiple factors beyond the commonly reported distance to health facility and lack of transportation and finances explained the low utilization of services. Emergent themes included a lack of understanding of the role of ANC beyond the treatment of regular ailments. Women with no complicated pregnancies therefore missed or went in late for the visits. A missed health visit contributed to future missed visits, not just for ANC but also for facility delivery and postnatal care. The underlying cause of this relationship was a fear of reprimand from the health staff and denial of care. The negative attitude of the health workers explained the pervasive fear expressed by the participants, as well as being on its own a reason for not making the visits. The effect was not just on the woman with the negative experience, but spiraled and affected the decision of other women and their social networks. CONCLUSIONS: The complexity of the barriers to healthcare visits implies that narrow focused solutions are unlikely to succeed. Instead, there should broad-based solutions that focus on the entire continuum of maternal care with a special focus on ANC. There is an urgent need to shift the negative attitude of healthcare workers towards their clients.


Assuntos
Parto Obstétrico , Parto Domiciliar/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde , Cuidado Pós-Natal , Cuidado Pré-Natal , Adulto , Atitude do Pessoal de Saúde , Parto Obstétrico/métodos , Parto Obstétrico/estatística & dados numéricos , Feminino , Acessibilidade aos Serviços de Saúde/normas , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Humanos , Quênia/epidemiologia , Mortalidade Materna , Avaliação das Necessidades , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Cuidado Pós-Natal/métodos , Cuidado Pós-Natal/normas , Cuidado Pós-Natal/estatística & dados numéricos , Gravidez , Cuidado Pré-Natal/organização & administração , Cuidado Pré-Natal/normas , Cuidado Pré-Natal/estatística & dados numéricos , Pesquisa Qualitativa , Melhoria de Qualidade
3.
Lancet ; 388(10051): 1291-301, 2016 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-27673470

RESUMO

BACKGROUND: Diarrhoea is the second leading cause of mortality in children worldwide, but establishing the cause can be complicated by diverse diagnostic approaches and varying test characteristics. We used quantitative molecular diagnostic methods to reassess causes of diarrhoea in the Global Enteric Multicenter Study (GEMS). METHODS: GEMS was a study of moderate to severe diarrhoea in children younger than 5 years in Africa and Asia. We used quantitative real-time PCR (qPCR) to test for 32 enteropathogens in stool samples from cases and matched asymptomatic controls from GEMS, and compared pathogen-specific attributable incidences with those found with the original GEMS microbiological methods, including culture, EIA, and reverse-transcriptase PCR. We calculated revised pathogen-specific burdens of disease and assessed causes in individual children. FINDINGS: We analysed 5304 sample pairs. For most pathogens, incidence was greater with qPCR than with the original methods, particularly for adenovirus 40/41 (around five times), Shigella spp or enteroinvasive Escherichia coli (EIEC) and Campylobactor jejuni o C coli (around two times), and heat-stable enterotoxin-producing E coli ([ST-ETEC] around 1·5 times). The six most attributable pathogens became, in descending order, Shigella spp, rotavirus, adenovirus 40/41, ST-ETEC, Cryptosporidium spp, and Campylobacter spp. Pathogen-attributable diarrhoeal burden was 89·3% (95% CI 83·2-96·0) at the population level, compared with 51·5% (48·0-55·0) in the original GEMS analysis. The top six pathogens accounted for 77·8% (74·6-80·9) of all attributable diarrhoea. With use of model-derived quantitative cutoffs to assess individual diarrhoeal cases, 2254 (42·5%) of 5304 cases had one diarrhoea-associated pathogen detected and 2063 (38·9%) had two or more, with Shigella spp and rotavirus being the pathogens most strongly associated with diarrhoea in children with mixed infections. INTERPRETATION: A quantitative molecular diagnostic approach improved population-level and case-level characterisation of the causes of diarrhoea and indicated a high burden of disease associated with six pathogens, for which targeted treatment should be prioritised. FUNDING: Bill & Melinda Gates Foundation.


Assuntos
Efeitos Psicossociais da Doença , Diarreia/microbiologia , Diarreia/virologia , Adenoviridae/isolamento & purificação , Adenoviridae/patogenicidade , África/epidemiologia , Ásia/epidemiologia , Bactérias/isolamento & purificação , Bactérias/patogenicidade , Infecções Bacterianas/diagnóstico , Campylobacter/isolamento & purificação , Campylobacter/patogenicidade , Estudos de Casos e Controles , Pré-Escolar , Coinfecção , Cryptosporidium/isolamento & purificação , Cryptosporidium/patogenicidade , Diarreia/epidemiologia , Escherichia coli/isolamento & purificação , Escherichia coli/patogenicidade , Feminino , Humanos , Incidência , Lactente , Masculino , Rotavirus/isolamento & purificação , Rotavirus/patogenicidade , Shigella/isolamento & purificação , Shigella/patogenicidade , Viroses/diagnóstico , Vírus/isolamento & purificação , Vírus/patogenicidade
4.
J Clin Microbiol ; 54(1): 49-58, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26491176

RESUMO

Acute febrile illness (AFI) is associated with substantial morbidity and mortality worldwide, yet an etiologic agent is often not identified. Convalescent-phase serology is impractical, blood culture is slow, and many pathogens are fastidious or impossible to cultivate. We developed a real-time PCR-based TaqMan array card (TAC) that can test six to eight samples within 2.5 h from sample to results and can simultaneously detect 26 AFI-associated organisms, including 15 viruses (chikungunya, Crimean-Congo hemorrhagic fever [CCHF] virus, dengue, Ebola virus, Bundibugyo virus, Sudan virus, hantaviruses [Hantaan and Seoul], hepatitis E, Marburg, Nipah virus, o'nyong-nyong virus, Rift Valley fever virus, West Nile virus, and yellow fever virus), 8 bacteria (Bartonella spp., Brucella spp., Coxiella burnetii, Leptospira spp., Rickettsia spp., Salmonella enterica and Salmonella enterica serovar Typhi, and Yersinia pestis), and 3 protozoa (Leishmania spp., Plasmodium spp., and Trypanosoma brucei). Two extrinsic controls (phocine herpesvirus 1 and bacteriophage MS2) were included to ensure extraction and amplification efficiency. Analytical validation was performed on spiked specimens for linearity, intra-assay precision, interassay precision, limit of detection, and specificity. The performance of the card on clinical specimens was evaluated with 1,050 blood samples by comparison to the individual real-time PCR assays, and the TAC exhibited an overall 88% (278/315; 95% confidence interval [CI], 84% to 92%) sensitivity and a 99% (5,261/5,326, 98% to 99%) specificity. This TaqMan array card can be used in field settings as a rapid screen for outbreak investigation or for the surveillance of pathogens, including Ebola virus.


Assuntos
Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/epidemiologia , Surtos de Doenças , Febre de Causa Desconhecida/diagnóstico , Febre de Causa Desconhecida/epidemiologia , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adulto , Monitoramento Epidemiológico , Humanos , Técnicas de Diagnóstico Molecular/normas , Reação em Cadeia da Polimerase em Tempo Real/normas , Padrões de Referência , Sensibilidade e Especificidade , Fatores de Tempo
5.
J Med Entomol ; 51(1): 269-77, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24605478

RESUMO

Biodiversity and relative abundance of ticks and associated arboviruses in Garissa (northeastern) and Isiolo (eastern) provinces of Kenya were evaluated. Ticks were collected from livestock, identified to species, pooled, and processed for virus isolation. In Garissa, Rhipicephalus pulchellus Gerstacker (57.8%) and Hyalomma truncatum Koch (27.8%) were the most abundant species sampled, whereas R. pulchellus (80.4%) and Amblyomma gemma Donitz (9.6%) were the most abundant in Isiolo. Forty-four virus isolates, comprising Dugbe virus (DUGV; n = 22) and Kupe virus (n = 10; Bunyaviridae: Nirovirus), Dhori virus (DHOV; n = 10; Orthomyxoviridae: Thogotovirus),and Ngari virus (NRIV; n = 2; Bunyaviridae: Orthobunyavirus), were recovered mostly from R. pulchellus sampled in Isiolo. DUGV was mostly recovered from R. pulchellus from sheep and cattle, and DHOV from R. pulchellus from sheep. All Kupe virus isolates were from Isiolo ticks, including R. pulchellus from all the livestock, A. gemma and Amblyomma variegatum F. from cattle, and H. truncatum from goat. NRIV was obtained from R. pulchellus and A. gemma sampled from cattle in Isiolo and Garissa, respectively, while all DHOV and most DUGV (n = 12) were from R. pulchellus sampled from cattle in Garissa. DUGV was also recovered from H. truncatum and Amblyomma hebraeum Koch from cattle and from Rhipicephalus annulatus Say from camel. This surveillance study has demonstrated the circulation of select tick-borne viruses in parts of eastern and northeastern provinces of Kenya, some of which are of public health importance. The isolation of NRIV from ticks is particularly significant because it is usually known to be a mosquito-borne virus affecting humans.


Assuntos
Arbovírus/isolamento & purificação , Vetores Artrópodes/virologia , Carrapatos/virologia , Animais , Camelus/parasitologia , Bovinos , Cabras/parasitologia , Humanos , Quênia , Ovinos/parasitologia
6.
Virol J ; 10: 140, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23663381

RESUMO

BACKGROUND: Increased frequency of arbovirus outbreaks in East Africa necessitated the determination of distribution of risk by entomologic arbovirus surveillance. A systematic vector surveillance programme spanning 5 years and covering 11 sites representing seven of the eight provinces in Kenya and located in diverse ecological zones was carried out. METHODS: Mosquitoes were sampled bi-annually during the wet seasons and screened for arboviruses. Mosquitoes were identified to species, pooled by species, collection date and site and screened for arboviruses by isolation in cell culture and/or RT-PCR screening and sequencing. RESULTS: Over 450,000 mosquitoes in 15,890 pools were screened with 83 viruses being detected/isolated that include members of the alphavirus, flavivirus and orthobunyavirus genera many of which are known to be of significant public health importance in the East African region. These include West Nile, Ndumu, Sindbis, Bunyamwera, Pongola and Usutu viruses detected from diverse sites. Ngari virus, which was associated with hemorrhagic fever in northern Kenya in 1997/98 was isolated from a pool of Anopheles funestus sampled from Tana-delta and from Aedes mcintoshi from Garissa. Insect only flaviviruses previously undescribed in Kenya were also isolated in the coastal site of Rabai. A flavivirus most closely related to the Chaoyang virus, a new virus recently identified in China and two isolates closely related to Quang Binh virus previously unreported in Kenya were also detected. CONCLUSION: Active transmission of arboviruses of public health significance continues in various parts of the country with possible undetermined human impact. Arbovirus activity was highest in the pastoralist dominated semi-arid to arid zones sites of the country where 49% of the viruses were isolated suggesting a role of animals as amplifiers and indicating the need for improved arbovirus disease diagnosis among pastoral communities.


Assuntos
Aedes/virologia , Anopheles/virologia , Arbovírus/isolamento & purificação , Animais , Arbovírus/classificação , Arbovírus/genética , Monitoramento Epidemiológico , Quênia , Prevalência , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Cultura de Vírus
7.
Am J Trop Med Hyg ; 109(1): 22-31, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37253442

RESUMO

Typhoid fever burden can vary over time. Long-term data can inform prevention strategies; however, such data are lacking in many African settings. We reexamined typhoid fever incidence and antimicrobial resistance (AMR) over a 10-year period in Kibera, a densely populated urban informal settlement where a high burden has been previously described. We used data from the Population Based Infectious Diseases Surveillance platform to estimate crude and adjusted incidence rates and prevalence of AMR in nearly 26,000 individuals of all ages. Demographic and healthcare-seeking information was collected through household visits. Blood cultures were processed for patients with acute fever or lower respiratory infection. Between 2010 and 2019, 16,437 participants were eligible for blood culture and 11,848 (72.1%) had a culture performed. Among 11,417 noncontaminated cultures (96.4%), 237 grew Salmonella enterica serovar Typhi (2.1%). Overall crude and adjusted incidences were 95 and 188 cases per 100,000 person-years of observation (pyo), respectively. Annual crude incidence varied from 144 to 233 between 2010 and 2012 and from 9 to 55 between 2013 and 2018 and reached 130 per 100,000 pyo in 2019. Children 5-9 years old had the highest overall incidence (crude, 208; adjusted, 359 per 100,000 pyo). Among isolates tested, 156 of 217 were multidrug resistant (resistant to chloramphenicol, ampicillin, and trimethoprim/sulfamethoxazole [71.9%]) and 6 of 223 were resistant to ciprofloxacin (2.7%). Typhoid fever incidence resurged in 2019 after a prolonged period of low rates, with the highest incidence among children. Typhoid fever control measures, including vaccines, could reduce morbidity in this setting.


Assuntos
Febre Tifoide , Criança , Humanos , Pré-Escolar , Febre Tifoide/epidemiologia , Incidência , Quênia/epidemiologia , Salmonella typhi , Ciprofloxacina/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
8.
PLoS One ; 18(1): e0277657, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36696882

RESUMO

BACKGROUND: Accurate and timely diagnosis is essential in limiting the spread of SARS-CoV-2 infection. The reference standard, rRT-PCR, requires specialized laboratories, costly reagents, and a long turnaround time. Antigen RDTs provide a feasible alternative to rRT-PCR since they are quick, relatively inexpensive, and do not require a laboratory. The WHO requires that Ag RDTs have a sensitivity ≥80% and specificity ≥97%. METHODS: This evaluation was conducted at 11 health facilities in Kenya between March and July 2021. We enrolled persons of any age with respiratory symptoms and asymptomatic contacts of confirmed COVID-19 cases. We collected demographic and clinical information and two nasopharyngeal specimens from each participant for Ag RDT testing and rRT-PCR. We calculated the diagnostic performance of the Panbio™ Ag RDT against the US Centers for Disease Control and Prevention's (CDC) rRT-PCR test. RESULTS: We evaluated the Ag RDT in 2,245 individuals where 551 (24.5%, 95% CI: 22.8-26.3%) tested positive by rRT-PCR. Overall sensitivity of the Ag RDT was 46.6% (95% CI: 42.4-50.9%), specificity 98.5% (95% CI: 97.8-99.0%), PPV 90.8% (95% CI: 86.8-93.9%) and NPV 85.0% (95% CI: 83.4-86.6%). Among symptomatic individuals, sensitivity was 60.6% (95% CI: 54.3-66.7%) and specificity was 98.1% (95% CI: 96.7-99.0%). Among asymptomatic individuals, sensitivity was 34.7% (95% CI 29.3-40.4%) and specificity was 98.7% (95% CI: 97.8-99.3%). In persons with onset of symptoms <5 days (594/876, 67.8%), sensitivity was 67.1% (95% CI: 59.2-74.3%), and 53.3% (95% CI: 40.0-66.3%) among those with onset of symptoms >7 days (157/876, 17.9%). The highest sensitivity was 87.0% (95% CI: 80.9-91.8%) in symptomatic individuals with cycle threshold (Ct) values ≤30. CONCLUSION: The overall sensitivity and NPV of the Panbio™ Ag RDT were much lower than expected. The specificity of the Ag RDT was high and satisfactory; therefore, a positive result may not require confirmation by rRT-PCR. The kit may be useful as a rapid screening tool only for symptomatic patients in high-risk settings with limited access to rRT-PCR. A negative result should be interpreted based on clinical and epidemiological information and may require retesting by rRT-PCR.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Antígenos Virais , COVID-19/diagnóstico , Teste para COVID-19 , Instalações de Saúde , Quênia/epidemiologia , Reação em Cadeia da Polimerase , SARS-CoV-2/genética , Sensibilidade e Especificidade
9.
Gates Open Res ; 7: 101, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37990692

RESUMO

Background: SARS-CoV-2 has extensively spread in cities and rural communities, and studies are needed to quantify exposure in the population. We report seroprevalence of SARS-CoV-2 in two well-characterized populations in Kenya at two time points. These data inform the design and delivery of public health mitigation measures. Methods: Leveraging on existing population based infectious disease surveillance (PBIDS) in two demographically diverse settings, a rural site in western Kenya in Asembo, Siaya County, and an urban informal settlement in Kibera, Nairobi County, we set up a longitudinal cohort of randomly selected households with serial sampling of all consenting household members in March and June/July 2021. Both sites included 1,794 and 1,638 participants in the March and June/July 2021, respectively. Individual seroprevalence of SARS-CoV-2 antibodies was expressed as a percentage of the seropositive among the individuals tested, accounting for household clustering and weighted by the PBIDS age and sex distribution. Results: Overall weighted individual seroprevalence increased from 56.2% (95%CI: 52.1, 60.2%) in March 2021 to 63.9% (95%CI: 59.5, 68.0%) in June 2021 in Kibera. For Asembo, the seroprevalence almost doubled from 26.0% (95%CI: 22.4, 30.0%) in March 2021 to 48.7% (95%CI: 44.3, 53.2%) in July 2021. Seroprevalence was highly heterogeneous by age and geography in these populations-higher seroprevalence was observed in the urban informal settlement (compared to the rural setting), and children aged <10 years had the lowest seroprevalence in both sites. Only 1.2% and 1.6% of the study participants reported receipt of at least one dose of the COVID-19 vaccine by the second round of serosurvey-none by the first round. Conclusions: In these two populations, SARS-CoV-2 seroprevalence increased in the first 16 months of the COVID-19 pandemic in Kenya. It is important to prioritize additional mitigation measures, such as vaccine distribution, in crowded and low socioeconomic settings.

10.
Microbiol Resour Announc ; 11(4): e0124121, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35343778

RESUMO

An Escherichia coli strain (sequence type 636) was isolated from an adult residing in an urban informal settlement in Nairobi, Kenya, and was sequenced using the Illumina MiSeq platform. The draft genome was 5,075,726 bp, with a Col(BS512) plasmid plus aph(6)-Id, blaTEM-1B, and dfrA7 genes, which encode kanamycin, ampicillin, and trimethoprim resistance proteins, respectively.

11.
Viruses ; 14(8)2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-36016365

RESUMO

The majority of Kenya's > 3 million camels have antibodies against Middle East respiratory syndrome coronavirus (MERS-CoV), although human infection in Africa is rare. We enrolled 243 camels aged 0−24 months from 33 homesteads in Northern Kenya and followed them between April 2018 to March 2020. We collected and tested camel nasal swabs for MERS-CoV RNA by RT-PCR followed by virus isolation and whole genome sequencing of positive samples. We also documented illnesses (respiratory or other) among the camels. Human camel handlers were also swabbed, screened for respiratory signs, and samples were tested for MERS-CoV by RT-PCR. We recorded 68 illnesses among 58 camels, of which 76.5% (52/68) were respiratory signs and the majority of illnesses (73.5% or 50/68) were recorded in 2019. Overall, 124/4692 (2.6%) camel swabs collected from 83 (34.2%) calves in 15 (45.5%) homesteads between April−September 2019 screened positive, while 22 calves (26.5%) recorded reinfections (second positive swab following ≥ 2 consecutive negative tests). Sequencing revealed a distinct Clade C2 virus that lacked the signature ORF4b deletions of other Clade C viruses. Three previously reported human PCR positive cases clustered with the camel infections in time and place, strongly suggesting sporadic transmission to humans during intense camel outbreaks in Northern Kenya.


Assuntos
Infecções por Coronavirus , Coronavírus da Síndrome Respiratória do Oriente Médio , Animais , Anticorpos Antivirais , Camelus , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Surtos de Doenças , Humanos , Quênia/epidemiologia , Zoonoses
12.
PLoS Negl Trop Dis ; 16(8): e0010704, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36007074

RESUMO

A high burden of Salmonella enterica subspecies enterica serovar Typhi (S. Typhi) bacteremia has been reported from urban informal settlements in sub-Saharan Africa, yet little is known about the introduction of these strains to the region. Understanding regional differences in the predominant strains of S. Typhi can provide insight into the genomic epidemiology. We genetically characterized 310 S. Typhi isolates from typhoid fever surveillance conducted over a 12-year period (2007-2019) in Kibera, an urban informal settlement in Nairobi, Kenya, to assess the circulating strains, their antimicrobial resistance attributes, and how they relate to global S. Typhi isolates. Whole genome multi-locus sequence typing (wgMLST) identified 4 clades, with up to 303 pairwise allelic differences. The identified genotypes correlated with wgMLST clades. The predominant clade contained 290 (93.5%) isolates with a median of 14 allele differences (range 0-52) and consisted entirely of genotypes 4.3.1.1 and 4.3.1.2. Resistance determinants were identified exclusively in the predominant clade. Determinants associated with resistance to aminoglycosides were observed in 245 isolates (79.0%), sulphonamide in 243 isolates (78.4%), trimethoprim in 247 isolates (79.7%), tetracycline in 224 isolates (72.3%), chloramphenicol in 247 isolates (79.6%), ß-lactams in 239 isolates (77.1%) and quinolones in 62 isolates (20.0%). Multidrug resistance (MDR) determinants (defined as determinants conferring resistance to ampicillin, chloramphenicol and cotrimoxazole) were found in 235 (75.8%) isolates. The prevalence of MDR associated genes was similar throughout the study period (2007-2012: 203, 76.3% vs 2013-2019: 32, 72.7%; Fisher's Exact Test: P = 0.5478, while the proportion of isolates harboring quinolone resistance determinants increased (2007-2012: 42, 15.8% and 2013-2019: 20, 45.5%; Fisher's Exact Test: P<0.0001) following a decline in S. Typhi in Kibera. Some isolates (49, 15.8%) harbored both MDR and quinolone resistance determinants. There were no determinants associated with resistance to cephalosporins or azithromycin detected among the isolates sequenced in this study. Plasmid markers were only identified in the main clade including IncHI1A and IncHI1B(R27) in 226 (72.9%) isolates, and IncQ1 in 238 (76.8%) isolates. Molecular clock analysis of global typhoid isolates and isolates from Kibera suggests that genotype 4.3.1 has been introduced multiple times in Kibera. Several genomes from Kibera formed a clade with genomes from Kenya, Malawi, South Africa, and Tanzania. The most recent common ancestor (MRCA) for these isolates was from around 1997. Another isolate from Kibera grouped with several isolates from Uganda, sharing a common ancestor from around 2009. In summary, S. Typhi in Kibera belong to four wgMLST clades one of which is frequently associated with MDR genes and this poses a challenge in treatment and control.


Assuntos
Quinolonas , Febre Tifoide , Antibacterianos/farmacologia , Cloranfenicol , Humanos , Quênia/epidemiologia , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Salmonella typhi , Febre Tifoide/epidemiologia
13.
Emerg Infect Dis ; 17(8): 1502-5, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21801635

RESUMO

As part of ongoing arbovirus surveillance, we screened ticks obtained from livestock in northeastern Kenya in 2008 to assess the risk for human exposure to tick-borne viruses. Of 1,144 pools of 8,600 Hyalomma spp. ticks screened for Congo-Crimean hemorrhagic fever virus by reverse transcription PCR, 23 pools were infected, demonstrating a potential for human exposure.


Assuntos
Vetores Aracnídeos/virologia , Vírus da Febre Hemorrágica da Crimeia-Congo/isolamento & purificação , Ixodidae/virologia , Animais , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Febre Hemorrágica da Crimeia/transmissão , Febre Hemorrágica da Crimeia/virologia , Humanos , Quênia , Gado/parasitologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Infestações por Carrapato/parasitologia
14.
F1000Res ; 10: 853, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35528961

RESUMO

Introduction: Urban informal settlements may be disproportionately affected by the COVID-19 pandemic due to overcrowding and other socioeconomic challenges that make adoption and implementation of public health mitigation measures difficult. We conducted a seroprevalence survey in the Kibera informal settlement, Nairobi, Kenya, to determine the extent of SARS-CoV-2 infection. Methods: Members of randomly selected households from an existing population-based infectious disease surveillance (PBIDS) provided blood specimens between 27 th November and 5 th December 2020. The specimens were tested for antibodies to the SARS-CoV-2 spike protein. Seroprevalence estimates were weighted by age and sex distribution of the PBIDS population and accounted for household clustering. Multivariable logistic regression was used to identify risk factors for individual seropositivity.   Results: Consent was obtained from 523 individuals in 175 households, yielding 511 serum specimens that were tested. The overall weighted seroprevalence was 43.3% (95% CI, 37.4 - 49.5%) and did not vary by sex. Of the sampled households, 122(69.7%) had at least one seropositive individual. The individual seroprevalence increased by age from 7.6% (95% CI, 2.4 - 21.3%) among children (<5 years), 32.7% (95% CI, 22.9 - 44.4%) among children 5 - 9 years, 41.8% (95% CI, 33.0 - 51.1%) for those 10-19 years, and 54.9%(46.2 - 63.3%) for adults (≥20 years). Relative to those from medium-sized households (3 and 4 individuals), participants from large (≥5 persons) households had significantly increased odds of being seropositive, aOR, 1.98(95% CI, 1.17 - 1.58), while those from small-sized households (≤2 individuals) had increased odds but not statistically significant, aOR, 2.31 (95% CI, 0.93 - 5.74).  Conclusion: In densely populated urban settings, close to half of the individuals had an infection to SARS-CoV-2 after eight months of the COVID-19 pandemic in Kenya. This highlights the importance to prioritize mitigation measures, including COVID-19 vaccine distribution, in the crowded, low socioeconomic settings.


Assuntos
COVID-19 , Adulto , Anticorpos Antivirais , COVID-19/epidemiologia , Vacinas contra COVID-19 , Criança , Pré-Escolar , Humanos , Quênia/epidemiologia , Pandemias , Fatores de Risco , SARS-CoV-2 , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus
15.
Int J Infect Dis ; 93: 359-366, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32061860

RESUMO

OBJECTIVE: This study aimed at examining the socio-demographic, environmental and behavioural determinants of diarrhoea in children under five years in Kenya. METHODS: The study entailed an analysis of secondary data from the Kenya Demographic Health Survey (DHS) 2014 using STATA Corp 2010. A total of 19,889 children <5 years were in the study, out of whom 2,906 had diarrhoea in the last two weeks prior to the survey. Descriptive analysis of independent variables and logistic regression model was used to analyse risk factors associated with diarrhoea in children <5 years. RESULTS: The most significant risk factors (p < 0.05) associated with diarrhoea morbidity in children <5 years were child age (AOR 2.26 95% CI 1.64, 3.11), low level of caregiver's education (AOR 1.45 95% CI 1.11, 1.90) and unsafe disposal of children's faeces (AOR 1.29 95% CI 1.03, 1.61). Wealthier households (AOR 0.83 95% CI 0.68, 1) were protective for diarrhoea in children <5 years. CONCLUSION: Increasing caregiver education, wealthier households and promoting hygienic behaviours in poor households were associated with reducing diarrhoea. Programmes aimed at reducing diarrhoea may achieve better results in targeting caregivers with children in high risk age cohorts of 6-23 months.


Assuntos
Diarreia Infantil/epidemiologia , Adolescente , Adulto , Cuidadores , Pré-Escolar , Diarreia Infantil/etiologia , Características da Família , Fezes , Feminino , Inquéritos Epidemiológicos , Humanos , Lactente , Quênia/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Morbidade , Fatores de Risco , Adulto Jovem
16.
BMJ Open ; 9(11): e032161, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31699743

RESUMO

INTRODUCTION: A wealth of evidence from a range of country settings indicates that antenatal care, facility delivery and postnatal care can reduce maternal and child mortality and morbidity in high-burden settings. However, the utilisation of these services by pregnant women, particularly in low/middle-income country settings, is well below that recommended by the WHO. The Afya trial aims to assess the impact, cost-effectiveness and scalability of conditional cash transfers to promote increased utilisation of these services in rural Kenya and thus retain women in the continuum of care during pregnancy, birth and the postnatal period. This protocol describes the planned economic evaluation of the Afya trial. METHODS AND ANALYSIS: The economic evaluation will be conducted from the provider perspective as a within-trial analysis to evaluate the incremental costs and health outcomes of the cash transfer programme compared with the status quo. Incremental cost-effectiveness ratios will be presented along with a cost-consequence analysis where the incremental costs and all statistically significant outcomes will be listed separately. Sensitivity analyses will be undertaken to explore uncertainty and to ensure that results are robust. A fiscal space assessment will explore the affordability of the intervention. In addition, an analysis of equity impact of the intervention will be conducted. ETHICS AND DISSEMINATION: The study has received ethics approval from the Maseno University Ethics Review Committee, REF MSU/DRPI/MUERC/00294/16. The results of the economic evaluation will be disseminated in a peer-reviewed journal and presented at a relevant international conference. TRIAL REGISTRATION NUMBER: NCT03021070.


Assuntos
Continuidade da Assistência ao Paciente/economia , Análise Custo-Benefício , Parto Obstétrico , Estudos de Avaliação como Assunto , Cuidado Pós-Natal , Cuidado Pré-Natal , Projetos de Pesquisa , Feminino , Humanos , Quênia , Gravidez , População Rural
17.
Open Forum Infect Dis ; 6(10): ofz421, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31660376

RESUMO

BACKGROUND: The impact of influenza B virus circulation in Sub-Saharan Africa is not well described. METHODS: We analyzed data from acute respiratory illness (ARI) in Kenya. We assessed clinical features and age-specific hospitalization and outpatient visit rates by person-years for influenza B/Victoria and B/Yamagata and the extent to which circulating influenza B lineages in Kenya matched the vaccine strain component of the corresponding season (based on Northern Hemisphere [October-March] and Southern Hemisphere [April-September] vaccine availability). RESULTS: From 2012 to 2016, influenza B represented 31% of all influenza-associated ARIs detected (annual range, 13-61%). Rates of influenza B hospitalization and outpatient visits were higher for <5 vs ≥5 years. Among <5 years, B/Victoria was associated with pneumonia hospitalization (64% vs 44%; P = .010) and in-hospital mortality (6% vs 0%; P = .042) compared with B/Yamagata, although the mean annual hospitalization rate for B/Victoria was comparable to that estimated for B/Yamagata. The 2 lineages co-circulated, and there were mismatches with available trivalent influenza vaccines in 2/9 seasons assessed. CONCLUSIONS: Influenza B causes substantial burden in Kenya, particularly among children aged <5 years, in whom B/Victoria may be associated with increased severity. Our findings suggest a benefit from including both lineages when considering influenza vaccination in Kenya.

18.
Trials ; 20(1): 152, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30823886

RESUMO

BACKGROUND: Antenatal care (ANC), facility delivery and postnatal care (PNC) are proven to reduce maternal and child mortality and morbidity in high-burden settings. However, few pregnant rural women use these services sufficiently. This study aims to assess the impact, cost-effectiveness and scalability of conditional cash transfers to promote increased contact between pregnant women or women who have recently given birth and the formal healthcare system in Kenya. METHODS: The intervention tested is a conditional cash transfer to women for ANC health visits, a facility birth and PNC visits until their newborn baby reaches 1 year of age. The study is a cluster randomized controlled trial in Siaya County, Kenya. The trial clusters are 48 randomly selected public primary health facilities, 24 of which are in the intervention arm of the study and 24 in the control arm. The unit of randomization is the health facility. A target sample of 7200 study participants comprises pregnant women identified and recruited at their first ANC visit over a 12-month recruitment period and their subsequent newborns. All pregnant women attending one of the selected trial facilities for their first ANC visit during the recruitment period are eligible for the trial and invited to participate. Enrolled mothers are followed up at all health visits during their pregnancy, at facility delivery and for a number of visits after delivery. They are also contacted at three additional time points after enrolling in the study: 5-10days after enrolment, 6 months after the expected delivery date and 12 27 months after birth. If they have not delivered in a facility, there is an additional follow-up 2 wees after the expected due date. The impact of the conditional cash transfers on maternal healthcare services and utilization will be measured by the trial's primary outcomes: the proportion of all eligible ANC visits made during pregnancy, delivery at a health facility, the proportion of all eligible PNC visits attended, the proportion of referrals attended during the pregnancy and the postnatal period, and the proportion of eligible child immunization appointments attended. Secondary outcomes include; health screening and infection control, live birth, maternal and child survival 48 h after delivery, exclusive breastfeeding, post-partum contraceptive use and maternal and newborn morbidity. Data sources for the measurement of outcomes include routine health records, an electronic card-reader system and telephone surveys and focus group discussions. A full economic evaluation will be conducted to assess the cost of delivery and cost effectiveness of the intervention and the benefit incidence and equity impact of trial activities and outcomes. DISCUSSION: This trial will contribute to evidence on the effectiveness and cost-effectiveness of conditional cash transfers in facilitating health visits and promoting maternal and child health in rural Kenya and in other comparable contexts. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03021070 . Registered on 13 January 2017.


Assuntos
Continuidade da Assistência ao Paciente/economia , Apoio Financeiro , Financiamento Pessoal/economia , Custos de Cuidados de Saúde , Cooperação do Paciente , Assistência Perinatal/economia , Serviços de Saúde Rural/economia , Análise Custo-Benefício , Feminino , Humanos , Lactente , Recém-Nascido , Quênia , Motivação , Assistência Perinatal/métodos , Pobreza/economia , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo
19.
Am J Trop Med Hyg ; 98(2): 625-632, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29280432

RESUMO

The use of fever syndromic surveillance in sub-Saharan Africa is an effective approach to determine the prevalence of both malarial and nonmalarial infectious agents. We collected both blood and naso/oro-pharyngeal (NP/OP) swabs from consecutive consenting patients ≥ 1 year of age, with an axillary temperature ≥ 37.5°C, and symptom onset of ≤ 5 days. Specimens were analyzed using both acute febrile illness (AFI) and respiratory TaqMan array cards (Resp TAC) for multiagent detection of 56 different bloodstream and respiratory agents. In addition, we collected epidemiologic data to further characterize our patient population. We enrolled 205 febrile patients, including 70 children (1 < 15 years of age; 34%) and 135 adults (≥ 15 years of age; 66%). AFI TAC and Resp TAC were performed on 191 whole blood specimens and 115 NP/OP specimens, respectively. We detected nucleic acid for Plasmodium (57%), Leptospira (2%), and dengue virus (1%) among blood specimens. In addition, we detected 17 different respiratory agents, most notably, Haemophilus influenzae (64%), Streptococcus pneumonia (56%), Moraxella catarrhalis (39%), and respiratory syncytial virus (11%) among NP/OP specimens. Overall median cycle threshold was measured at 26.5. This study provides a proof-of-concept for the use of a multiagent diagnostic approach for exploratory research on febrile illness and underscores the utility of quantitative molecular diagnostics in complex epidemiologic settings of sub-Saharan Africa.


Assuntos
Febre/microbiologia , Febre/parasitologia , Febre/virologia , Síndrome , Adolescente , Adulto , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , População Rural/estatística & dados numéricos , Tanzânia/epidemiologia
20.
Sci Data ; 5: 180186, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30226483

RESUMO

The two datasets outlined in this paper contain information related to (a) the local impacts of biofuel feedstock production, and (b) the factors that influence the adoption and/or sustained use of ethanol stoves in southern Africa. The first dataset was generated through extensive household surveys around four operational jatropha and sugarcane production sites in Malawi, Mozambique, and Swaziland. This project aimed to examine the local impacts of the most prominent modes of existing or intended biofuel feedstock production in southern Africa. The resulting dataset contains information about impacts on rural livelihoods, ecosystem services, food security and poverty alleviation. The second dataset is the outcome of research into factors that influence the adoption and sustained use of ethanol stoves. This dataset was collected through a household survey in Maputo city where the only large-scale ethanol stove dissemination programme in Africa has been implemented.


Assuntos
Biocombustíveis , Produção Agrícola , África Austral , Etanol , Características da Família
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