BackgroundDisease caused by the dengue virus (DENV) is a significant cause of morbidity throughout the world. Although prior research has focused on the association of specific DENV serotypes (DENV-1, DENV-2, DENV-3, and DENV-4) with the development of severe outcomes such as dengue hemorrhagic fever and dengue shock syndrome, relatively little work has correlated other clinical manifestations with a particular DENV serotype. The goal of this study was to estimate and compare the prevalence of non-hemorrhagic clinical manifestations of DENV infection by serotype.Methodology and Principal FindingsBetween the years 2005–2010, individuals with febrile disease from Peru, Bolivia, Ecuador, and Paraguay were enrolled in an outpatient passive surveillance study. Detailed information regarding clinical signs and symptoms, as well as demographic information, was collected. DENV infection was confirmed in patient sera with polyclonal antibodies in a culture-based immunofluorescence assay, and the infecting serotype was determined by serotype-specific monoclonal antibodies. Differences in the prevalence of individual and organ-system manifestations were compared across DENV serotypes. One thousand seven hundred and sixteen individuals were identified as being infected with DENV-1 (39.8%), DENV-2 (4.3%), DENV-3 (41.5%), or DENV-4 (14.4%). When all four DENV serotypes were compared with each other, individuals infected with DENV-3 had a higher prevalence of musculoskeletal and gastrointestinal manifestations, and individuals infected with DENV-4 had a higher prevalence of respiratory and cutaneous manifestations.Conclusions/SignificanceSpecific clinical manifestations, as well as groups of clinical manifestations, are often overrepresented by an individual DENV serotype.

BackgroundHighly refined surveillance data on the 2009 A/H1N1 influenza pandemic are crucial to quantify the spatial and temporal characteristics of the pandemic. There is little information about the spatial-temporal dynamics of pandemic influenza in South America. Here we provide a quantitative description of the age-specific morbidity pandemic patterns across administrative areas of Peru.MethodsWe used daily cases of influenza-like-illness, tests for A/H1N1 influenza virus infections, and laboratory-confirmed A/H1N1 influenza cases reported to the epidemiological surveillance system of Peru's Ministry of Health from May 1 to December 31, 2009. We analyzed the geographic spread of the pandemic waves and their association with the winter school vacation period, demographic factors, and absolute humidity. We also estimated the reproduction number and quantified the association between the winter school vacation period and the age distribution of cases.ResultsThe national pandemic curve revealed a bimodal winter pandemic wave, with the first peak limited to school age children in the Lima metropolitan area, and the second peak more geographically widespread. The reproduction number was estimated at 1.6–2.2 for the Lima metropolitan area and 1.3–1.5 in the rest of Peru. We found a significant association between the timing of the school vacation period and changes in the age distribution of cases, while earlier pandemic onset was correlated with large population size. By contrast there was no association between pandemic dynamics and absolute humidity.ConclusionsOur results indicate substantial spatial variation in pandemic patterns across Peru, with two pandemic waves of varying timing and impact by age and region. Moreover, the Peru data suggest a hierarchical transmission pattern of pandemic influenza A/H1N1 driven by large population centers. The higher reproduction number of the first pandemic wave could be explained by high contact rates among school-age children, the age group most affected during this early wave.

SimposioCitar como: Cabezas C, Fiestas V, García-Mendoza M, Palomino M, Mamani E, Donaires F. Dengue en el Perú: a un cuarto de siglo de su reemergencia. Rev Peru Med Exp Salud Publica. 2015;32(1):146-56. RESUMENUn problema sanitario cada vez más frecuente y disperso en áreas tropicales y subtropicales del mundo, incluido el Perú donde ingresó en 1990, es el dengue. Es producido por el virus del dengue con cuatro serotipos y transmitido por el Aedes aegypti, vector que convive con los humanos y cuya presencia es favorecida por deficientes condiciones sanitarias, sociales y económicas. Manifestaciones de formas severas de la enfermedad como el choque y sangrado, están relacionadas con la frecuente cocirculación de los cuatro serotipos y la aparición de nuevos genotipos como el americano/asiático del serotipo 2. La nueva clasificación de la enfermedad por la OMS como dengue con o sin signos de alarma y dengue grave, está contribuyendo a un diagnóstico y tratamiento más oportunos, permitiendo reducir la letalidad. Debe destacarse la necesidad de la vigilancia del síndrome febril y los índices aédicos que contribuyan a un diagnóstico oportuno y orienten las medidas de control vectorial mediante educación sanitaria y manejo ambiental con participación comunitaria e intersectorial, de manera creativa según los nichos ecológicos. Una alternativa de prevención complementaria sería la vacunación utilizando vacunas tetravalentes cuya seguridad y eficacia deben estar garantizadas antes de su uso poblacional en el marco de estrategias integrales. Palabras clave: Dengue; Aedes aegypti; Enfermedades transmisibles emergentes (fuente: DeCS BIREME). ABSTRACTA health problem each time more frequent and dispersed in tropical and subtropical areas of the world, including Peru where it entered in 1990, is dengue. It is produced by the dengue virus with four serotypes and transmitted by Aedes aegypti, a vector that coexists with humans and whose presence is favored by deficient sanitary, social and economic conditions. Manifestations of severe forms of the disease such as shock and bleeding, are related to the frequent co-circulation of the four serotypes and the emergence of new genotypes such as American / Asian serotype 2. The new classification of the disease by WHO as dengue with or without warning signs and severe dengue, is contributing to more timely diagnosis and treatment, enabling reductions in mortality. Of note is the need to highlight the surveillance of acute febrile illness and Aedes indices that contribute to a timely diagnosis and guide vector control measures through sanitary education and environmental management with community and intersectoral participation, in a creative manner according to ecological niches. An alternative for complementary prevention would be vaccination using tetravalent vaccines whose safety and efficacy must be guaranteed before its use in the population under the framework of comprehensive strategies.

High levels of Plasmodium falciparum resistance to both chloroquine (CQ) and sulfadoxine-pyrimethamine (SP) have been documented throughout the Amazon Basin of South America. Because of reports about the persistent efficacy of both of these drugs in the northwestern Peruvian Amazon region, we carried out an evaluation of the therapeutic efficacy of chloroquine (25 mg/kg) and SP (25 mg/kg of the sulfadoxine component) for the treatment of uncomplicated P. falciparum infections at two sites: Ullpayacu and Pampa Hermoza/Alianza. A total of 111 patients were enrolled. Only 5 (14.3%) of the 35 patients who received CQ had an adequate clinical and parasitologic response (ACPR). Six subjects (17%) had early treatment failure, 1 (2.9%) had late clinical failure, and 23 (65.7%) had late parasitologic failure (LPF). Of the subjects treated with SP, 92.3% had ACPR and 7.7% had LPF. Based on these findings, it is clear that there are at least limited areas within the Peruvian Amazon region where P. falciparum strains continue to be sensitive to SP.