Challenges of design, implementation, acceptability, and potential for, biomedical technologies in the Peruvian Amazon.

BACKGROUND: Biomedical technologies have the potential to be advantageous in remote communities. However, information about barriers faced by users of technology in general and in remote Indigenous communities is scarce. The purpose of this study was to characterize the leading challenges faced by researchers who have used biomedical technologies in the Peruvian Amazon. METHODS: This exploratory, qualitative study with a phenomenological approach depicts the lived experience of participants who were researchers with experience working with biomedical technologies in the Peruvian Amazon in the past five years. Analysis was based on three core themes: design, implementation, and acceptability. Sub-themes included environment, community, and culture. Of the 24 potential participants identified and contacted, 14 agreed to participate, and 13 met inclusion criteria and completed semi-structured interviews. Results were sent to each participant with the opportunity to provide feedback and partake in a 30-minute validation meeting. Five participants consented to a follow-up meeting to validate the results and provide further understanding. RESULTS: Participants recognized significant challenges, including technologies designed out-of-context, difficulty transporting the technologies through the Amazon, the impact of the physical environment (e.g., humidity, flooding), and limited existing infrastructure, such as electricity and appropriately trained health personnel. Participants also identified cultural factors, including the need to address past experiences with technology and health interventions, understand and appropriately communicate community benefits, and understand the effect of demographics (e.g., age, education) on the acceptance and uptake of technology. Complementary challenges, such as corruption in authority and waste disposal, and recommendations for technological and health interventions such as co-design were also identified. CONCLUSIONS: This study proposes that technological and health interventions without efforts to respect local cultures and health priorities, or understand and anticipate contextual challenges, will not meet its goal of improving access to healthcare in remote Amazon communities. Furthermore, the implications of corruption on health services, and improper waste disposal on the environment may lead to more detrimental health inequities.

Guaroa Virus and Plasmodium vivax Co-Infections, Peruvian Amazon.

During April-June 2014 in a malaria-endemic rural community close to the city of Iquitos in Peru, we detected evidence of Guaroa virus (GROV) infection in 14 febrile persons, of whom 6 also had evidence of Plasmodium vivax malaria. Cases were discovered through a long-term febrile illness surveillance network at local participating health facilities. GROV cases were identified by using a combination of seroconversion and virus isolation, and malaria was diagnosed by thick smear and PCR. GROV mono-infections manifested as nonspecific febrile illness and were clinically indistinguishable from GROV and P. vivax co-infections. This cluster of cases highlights the potential for GROV transmission in the rural Peruvian Amazon, particularly in areas where malaria is endemic. Further study of similar areas of the Amazon may provide insights into the extent of GROV transmission in the Amazon basin.

Heterogeneity of Dengue Illness in Community-Based Prospective Study, Iquitos, Peru.

Measuring heterogeneity of dengue illness is necessary to define suitable endpoints in dengue vaccine and therapeutic trials and will help clarify behavioral responses to illness. To quantify heterogeneity in dengue illness, including milder cases, we developed the Dengue Illness Perceptions Response (IPR) survey, which captured detailed symptom data, including intensity, duration, and character, and change in routine activities caused by illness. During 2016-2019, we collected IPR data daily during the acute phase of illness for 79 persons with a positive reverse transcription PCR result for dengue virus RNA. Most participants had mild ambulatory disease. However, we measured substantial heterogeneity in illness experience, symptom duration, and maximum reported intensity of individual symptoms. Symptom intensity was a more valuable predicter of major activity change during dengue illness than symptom presence or absence alone. These data suggest that the IPR measures clinically useful heterogeneity in dengue illness experience and its relation to altered human behavior.

Diffuse Multibacillary Leprosy of Lucio and Latapí with Lucio's Phenomenon, Peru.

Diffuse multibacillary leprosy of Lucio and Latapí is mainly reported in Mexico and Central America. We report a case in a 65-year-old man in Peru. He also had Lucio's phenomenon, characterized by vascular thrombosis and invasion of blood vessel walls by leprosy bacilli, causing extensive skin ulcers.

Time-varying, serotype-specific force of infection of dengue virus.

Infectious disease models play a key role in public health planning. These models rely on accurate estimates of key transmission parameters such as the force of infection (FoI), which is the per-capita risk of a susceptible person being infected. The FoI captures the fundamental dynamics of transmission and is crucial for gauging control efforts, such as identifying vaccination targets. Dengue virus (DENV) is a mosquito-borne, multiserotype pathogen that currently infects ∼390 million people a year. Existing estimates of the DENV FoI are inaccurate because they rely on the unrealistic assumption that risk is constant over time. Dengue models are thus unreliable for designing vaccine deployment strategies. Here, we present to our knowledge the first time-varying (daily), serotype-specific estimates of DENV FoIs using a spline-based fitting procedure designed to examine a 12-y, longitudinal DENV serological dataset from Iquitos, Peru (11,703 individuals, 38,416 samples, and 22,301 serotype-specific DENV infections from 1999 to 2010). The yearly DENV FoI varied markedly across time and serotypes (0-0.33), as did daily basic reproductive numbers (0.49-4.72). During specific time periods, the FoI fluctuations correlated across serotypes, indicating that different DENV serotypes shared common transmission drivers. The marked variation in transmission intensity that we detected indicates that intervention targets based on one-time estimates of the FoI could underestimate the level of effort needed to prevent disease. Our description of dengue virus transmission dynamics is unprecedented in detail, providing a basis for understanding the persistence of this rapidly emerging pathogen and improving disease prevention programs.

House-to-house human movement drives dengue virus transmission.

Dengue is a mosquito-borne disease of growing global health importance. Prevention efforts focus on mosquito control, with limited success. New insights into the spatiotemporal drivers of dengue dynamics are needed to design improved disease-prevention strategies. Given the restricted range of movement of the primary mosquito vector, Aedes aegypti, local human movements may be an important driver of dengue virus (DENV) amplification and spread. Using contact-site cluster investigations in a case-control design, we demonstrate that, at an individual level, risk for human infection is defined by visits to places where contact with infected mosquitoes is likely, independent of distance from the home. Our data indicate that house-to-house human movements underlie spatial patterns of DENV incidence, causing marked heterogeneity in transmission rates. At a collective level, transmission appears to be shaped by social connections because routine movements among the same places, such as the homes of family and friends, are often similar for the infected individual and their contacts. Thus, routine, house-to-house human movements do play a key role in spread of this vector-borne pathogen at fine spatial scales. This finding has important implications for dengue prevention, challenging the appropriateness of current approaches to vector control. We argue that reexamination of existing paradigms regarding the spatiotemporal dynamics of DENV and other vector-borne pathogens, especially the importance of human movement, will lead to improvements in disease prevention.

Reduced risk of disease during postsecondary dengue virus infections.

BACKGROUND: Antibodies induced by infection with any 1 of 4 dengue virus (DENV) serotypes (DENV-1-4) may influence the clinical outcome of subsequent heterologous infections. To quantify potential cross-protective effects, we estimated disease risk as a function of DENV infection, using data from longitudinal studies performed from September 2006 through February 2011 in Iquitos, Peru, during periods of DENV-3 and DENV-4 transmission. METHODS: DENV infections before and during the study period were determined by analysis of serial serum samples with virus neutralization tests. Third and fourth infections were classified as postsecondary infections. Dengue fever cases were detected by door-to-door surveillance for acute febrile illness. RESULTS: Among susceptible participants, 39% (420/1077) and 53% (1595/2997) seroconverted to DENV-3 and DENV-4, respectively. Disease was detected in 7% of DENV-3 infections and 10% of DENV-4 infections. Disease during postsecondary infections was reduced by 93% for DENV-3 and 64% for DENV-4, compared with primary and secondary infections. Despite lower disease rates, postsecondary infections constituted a significant proportion of apparent infections (14% [for DENV-3 infections], 45% [for DENV-4 infections]). CONCLUSIONS: Preexisting heterotypic antibodies markedly reduced but did not eliminate the risk of disease in this study population. These results improve understanding of how preinfection history can be associated with dengue outcomes and DENV transmission dynamics.

Risk factors associated with dengue complications and death: A cohort study in Peru.

BACKGROUND: Dengue has emerged as an unprecedented epidemic in Peru, and it is anticipated that this issue will escalate further owing to climate change. This study aimed to determine the risk factors associated with death from dengue in patients treated at Hospital II in Pucallpa, Peru. METHODOLOGY: This retrospective cohort study collected information from the medical records of patients with a diagnosis of dengue treated at Hospital II Pucallpa-Peru between January 2019 and March 2023. The primary outcome was death, and the secondary outcome was death, development of severe dengue, or Intensive Care Unit (ICU) admission. Cox regression models were used to determine risk factors. FINDINGS: The clinical records of 152 patients were evaluated, with a median age of 27.5 years (interquartile range, 11-45). Among all patients, 29 (19.1%) developed severe dengue, 31 (20.4%) were admitted to the ICU, and 13 (8.6%) died during follow-up. In the survival analysis, bilirubin >1.2 mg/dL was associated with a higher risk of death aHR: 11.38 (95% CI: 1.2 106.8). Additionally, factors associated with poor prognosis included having 1 to 3 comorbidities aRR: 1.92 (1.2 to 3.2), AST ≥251 U/L aRR: 6.79 (2.2 to 21.4), history of previous dengue aRR: 1.84 (1.0 to 3.3), and fibrinogen ≥400 mg/dL aRR: 2.23 (1.2 to 4.1). SIGNIFICANCE: Elevated bilirubin was associated with death from dengue, whereas an increase in comorbidities and a history of previous dengue were related to a poor prognosis of the disease. Early identification of severe dengue would be more feasible with improved access to laboratory testing, particularly in tropical areas with a high dengue incidence.

Mayaro virus infection, Amazon Basin region, Peru, 2010-2013.

During 2010-2013, we recruited 16 persons with confirmed Mayaro virus infection in the Peruvian Amazon to prospectively follow clinical symptoms and serologic response over a 12-month period. Mayaro virus infection caused long-term arthralgia in more than half, similar to reports of other arthritogenic alphaviruses.

[Acute gastrointestinal involvement in dengue disease by serotype 4: a case report and literature review]. / Compromiso gastrointestinal agudo en pacientes con dengue por serotipo 4: Comunicación de un caso y revisión de la literatura.

Dengue fever is the world's most important arboviral disease, presenting a wide clinical spectrum. We report for the first time in Peru, a case caused by dengue virus serotype 4 with significant gastrointestinal involvement (acute acalculous cholecystitis and acute hepatitis). In addition we carried out a review of the literature atypical presentation illustrating the importance of the characteristics of abdominal pain (right upper quadrant); presence of Murphy's sign, ultrasound, and liver enzymes levels, for appropriate diagnosis and clinical management.

Pleural empyema by Parvimonas micra in an immunocompetent patient: a case report. / Empiema pleural por Parvimonas micra en un paciente inmunocompetente: reporte de un caso.

We present the case of a young immunocompetent patient, with a history of pulmonary tuberculosis, who attended the hospital with a subacute clinical picture of persistent fever, weight loss, dyspnea and abolition of vesicular murmur. Chest CT scan showed an extensive empyema in the left hemithorax. Samples were taken for detection of common germs. Then, a chest drainage tube was placed and antibiotic therapy started. The MALDI-TOF MS test identified Parvimonas micra, an anaerobic bacterium, commensal to the oral flora, associated with severe periodontitis, but rarely reported in cases of pleural empyema, especially in immunocompetent patients. Gingivitis and pericoronaritis of the third molar were diagnosed during oral evaluation. The patient progressed favorably. Parvimonas micra should be considered as a possible etiological agent in cases of subacute or chronic pleural empyema, in addition to mycobacteria. Tests such as MALDI-TOF MS or 16S rRNA sequencing, chest tube placement, empirical antibiotic coverage and an adequate oral evaluation should be considered in these cases.

Se presenta el caso de un paciente joven inmunocompetente, con antecedente de tuberculosis pulmonar, que acude al hospital por un cuadro clínico subagudo de fiebre persistente, baja de peso, disnea y abolición del murmullo vesicular. La tomografía de tórax mostró un extenso empiema en hemitórax izquierdo. Se le toman muestras para detección de gérmenes comunes y se le colocan un tubo de drenaje torácico y se inicia antibioticoterapia. La prueba de MALDI-TOF MS identificó a Parvimonas micra, una bacteria anaerobia, comensal de la flora oral, asociado a periodontitis severa, escasamente reportado en empiema pleural, especialmente, en personas inmunocompetentes. En la evaluación odontológica se realizó el diagnóstico de gingivitis y pericoronaritis de la tercera molar. El paciente evolucionó favorablemente. Se sugiere que, en casos de empiemas pleurales subagudos o crónicos, se debe considerar, además de las micobacterias, como agente etiológico al Parvimonas micra, y optar por exámenes como MALDI-TOF MS o secuenciamiento del 16S rRNA, colocación de tubo de tórax, cobertura antibiótica empírica y evaluación odontológica.

Feasibility of Training Community Health Workers to Use Smartphone-Attached Microscopy for Point-of-Care Visualization of Soil-Transmitted Helminths in the Peruvian Amazon.

The prevalence of soil-transmitted helminths (STH) is high in communities within the Peruvian Amazon despite repeated mass-drug administration, demanding alternative strategies of control. Smartphone-attached microscopy (SAM) permits visualization of STH from a small portable microscope through a smartphone screen, potentially providing an inexpensive and rapid method of STH visualization in communities where diagnostic laboratories with microscopes are inaccessible. In this study, a total of 45 community health workers who work within the health systems of Loreto, Peru, attended a 1-day training session with lectures and practicums on STH and SAM. Participants received a pre- and post-intervention questionnaire. Post-intervention, participants were significantly more confident using SAM and identifying parasite images, symptoms, transmission, and treatment (P ≤ 0.0045). Post-intervention, participants correctly labeled a median of five of seven SAM apparatus components and five of eight steps of Kato-Katz technique, were less likely to choose taking medicine to prevent parasite infection (P = 0.0075), and were more likely to select Kato-Katz technique as a type of diagnostic test (P < 0.0001). Most participants felt ready to use SAM in their communities and stated that it could help rural communities far from health centers or laboratories (24%); provide faster identification, results, diagnosis (19%); permit at-home or on-the-spot visualization (14%); and save money (14%). Results show that community health workers show a high level of willingness and competency to learn about both STH and SAM and may be a yet-unexplored practical method of augmenting STH visualization, bringing healthcare to communities in Loreto with poor access to diagnostic laboratories and clinics.

Direct mosquito feedings on dengue-2 virus-infected people reveal dynamics of human infectiousness.

Dengue virus (DENV) transmission from humans to mosquitoes is a poorly documented, but critical component of DENV epidemiology. Magnitude of viremia is the primary determinant of successful human-to-mosquito DENV transmission. People with the same level of viremia, however, can vary in their infectiousness to mosquitoes as a function of other factors that remain to be elucidated. Here, we report on a field-based study in the city of Iquitos, Peru, where we conducted direct mosquito feedings on people naturally infected with DENV and that experienced mild illness. We also enrolled people naturally infected with Zika virus (ZIKV) after the introduction of ZIKV in Iquitos during the study period. Of the 54 study participants involved in direct mosquito feedings, 43 were infected with DENV-2, two with DENV-3, and nine with ZIKV. Our analysis excluded participants whose viremia was detectable at enrollment but undetectable at the time of mosquito feeding, which was the case for all participants with DENV-3 and ZIKV infections. We analyzed the probability of onward transmission during 50 feeding events involving 27 participants infected with DENV-2 based on the presence of infectious virus in mosquito saliva 7-16 days post blood meal. Transmission probability was positively associated with the level of viremia and duration of extrinsic incubation in the mosquito. In addition, transmission probability was influenced by the day of illness in a non-monotonic fashion; i.e., transmission probability increased until 2 days after symptom onset and decreased thereafter. We conclude that mildly ill DENV-infected humans with similar levels of viremia during the first two days after symptom onset will be most infectious to mosquitoes on the second day of their illness. Quantifying variation within and between people in their contribution to DENV transmission is essential to better understand the biological determinants of human infectiousness, parametrize epidemiological models, and improve disease surveillance and prevention strategies.

[Brain abscess due to Nocardia sp. In an immunocompetent patient in Peru: a case report]. / Absceso cerebral por Nocardia sp. En un paciente inmunocompetente en el Perú: reporte de caso.

Cerebral nocardia infections is a rare entity, which has been mainly reported in immunosuppressed patients. Currently, there are no clinical guidelines for first-line treatment. Our case refers to an older immunocompetent adult, with encephalopathy and left hemiparesis, associated with lesions compatible with multiple brain abscess and suggestive of infectious etiology. He initially received treatment for tuberculosis, bacterial abscess, and toxoplasmosis, without a favorable clinical response. An empirical treatment for nocardiosis started, by using meropenem and trimethoprim / sulfamethoxazole, and clinical and imaging improvement was achieved. The occurrence of adverse events forces the temporary use of alternative medications. We highlight some criteria for including nocardiosis in the differential diagnosis in cases of multiple brain abscess and mention laboratory diagnostic methods and drugs to initiate empirical treatment.

La nocardiosis cerebral es una entidad rara que ha sido reportada principalmente en inmunosuprimidos, y en la actualidad no se dispone de guías clínicas que recomienden un tratamiento de primera línea. Presentamos el caso de un adulto mayor, inmunocompetente, con cuadro de encefalopatía y hemiparesia izquierda, asociado a lesiones compatibles con absceso cerebral múltiple y sugerente de etiología infecciosa. Recibió, inicialmente, tratamiento para la tuberculosis, absceso bacteriano y toxoplasmosis, sin respuesta clínica favorable. Se inició un tratamiento empírico para la nocardiosis con meropenem y trimetoprim/sulfametoxazol, y se logró mejoría clínica e imagenológica. La ocurrencia de eventos adversos obliga el uso temporal de medicamentos alternativos. Se resaltan algunos criterios a considerar para incluir la nocardiosis en el diagnóstico diferencial en los casos de absceso cerebral múltiple y se mencionan los métodos diagnósticos de laboratorio y los fármacos para iniciar un tratamiento empírico.

Serological Responses in Patients Infected with Mayaro Virus and Evaluation of Cross-Protective Responses against Chikungunya Virus.

Mayaro virus (MAYV) is an alphavirus endemic to both Latin America and the Caribbean. Recent reports have questioned the ability of MAYV and its close relative, Chikungunya virus (CHIKV), to generate cross-reactive, neutralizing antibodies to one another. Since CHIKV was introduced to South America in 2013, discerning whether individuals have cross-reactive antibodies or whether they have had exposures to both viruses previously has been difficult. Using samples obtained from people infected with MAYV prior to the introduction of CHIKV in the Americas, we performed neutralizing assays and observed no discernable neutralization of CHIKV by sera from patients previously infected with MAYV. These data suggest that a positive CHIKV neutralization test cannot be attributed to prior exposure to MAYV and that previous exposure to MAYV may not be protective against a subsequent CHIKV infection.

Venezuelan equine encephalitis and 2 human deaths, Peru.

Studies have suggested that enzootic strains of Venezuelan equine encephalitis (VEE) subtype ID in the Amazon region, Peru, may be less pathogenic to humans than are epizootic variants. Deaths of 2 persons with evidence of acute VEE virus infection indicate that fatal VEEV infection in Peru is likely. Cases may remain underreported.

Venezuelan equine encephalitis and upper gastrointestinal bleeding in child.

Venezuelan equine encephalitis (VEE) is reemerging in Peru. VEE virus subtype ID in Peru has not been previously associated with severe disease manifestations. In 2006, VEE virus subtype ID was isolated from a boy with severe febrile disease and gastrointestinal bleeding; the strain contained 2 mutations within the PE2 region.

Dengue virus serotype 4, northeastern Peru, 2008.

In 2008, dengue virus serotype 4 (DENV-4) emerged in northeastern Peru, causing a large outbreak and displacing DENV-3, which had predominated for the previous 6 years. Phylogenetic analysis of 2008 and 2009 isolates support their inclusion into DENV-4 genotype II, forming a lineage distinct from strains that had previously circulated in the region.