Avian Influenza in Wild Birds, Central Coast of Peru

To determine genotypes of avian influenza virus circulating among wild birds in South America, we collected and tested environmental fecal samples from birds along the coast of Peru, June 2006–December 2007. The 9 isolates recovered represented 4 low-pathogenicity avian influenza strains: subtypes H3N8, H4N5, H10N9, and H13N2

A community-based survey on influenza and vaccination knowledge, perceptions and practices in Peru.

BACKGROUND: Although Peru provides safe and effective influenza vaccines free-of-charge, coverage among vaccine target groups like pregnant women and older adults remains low. To improve risk communication messages and vaccine uptake, we explored knowledge, perceptions and practices about influenza illness and vaccination. METHODS: A cross-sectional, community-based survey with a three-stage cluster sampling design was conducted in three cities in Peru. We included mothers of young children, pregnant women and persons ≥65 years. Participants completed a questionnaire about knowledge, perceptions and practices about influenza illness and vaccination against influenza during the past year. Generalized linear models were used to explore factors associated with vaccination in the past year. RESULTS: 624/645 (97%) mothers, 54/55 (98%) pregnant women and 622/673 (92%) older adults approached provided informed consent and were surveyed. While most mothers, pregnant women and older adults (94%, 96% and 91%, respectively) perceived influenza as a potentially serious illness, few pregnant women (13%) and older adults (34%) self-identified themselves as a target group for influenza vaccination. Only 28% of mothers, 19% pregnant women, and 27% older adults were vaccinated against influenza during the previous year. Among the participants that did not get vaccinated against influenza in the previous year, "being afraid of vaccination and its effects" was the most commonly cited barrier. Knowledge of the recommendation for annual vaccination was significantly associated with vaccination status among pregnant women (p = 0.048) and older adults (p = 0.004). CONCLUSION: Despite a government subsidized vaccine program, vaccine utilization remained low among pregnant women and older adults, who seemed typically unaware of their status as high-risk groups targeted for vaccination. Those aware of the recommendations for annual vaccination were more likely to be vaccinated. Information campaigns addressing fears and highlighting populations at risk for severe influenza illness that are targeted for vaccination might increase vaccine coverage in Peru

Global patterns in monthly activity of influenza virus, respiratory syncytial virus, parainfluenza virus, and metapneumovirus: a systematic analysis

Background: Influenza virus, respiratory syncytial virus, parainfluenza virus, and metapneumovirus are the most common viruses associated with acute lower respiratory infections in young children (<5 years) and older people (≥65 years). A global report of the monthly activity of these viruses is needed to inform public health strategies and programmes for their control. Methods: In this systematic analysis, we compiled data from a systematic literature review of studies published between Jan 1, 2000, and Dec 31, 2017; online datasets; and unpublished research data. Studies were eligible for inclusion if they reported laboratory-confirmed incidence data of human infection of influenza virus, respiratory syncytial virus, parainfluenza virus, or metapneumovirus, or a combination of these, for at least 12 consecutive months (or 52 weeks equivalent); stable testing practice throughout all years reported; virus results among residents in well-defined geographical locations; and aggregated virus results at least on a monthly basis. Data were extracted through a three-stage process, from which we calculated monthly annual average percentage (AAP) as the relative strength of virus activity. We defined duration of epidemics as the minimum number of months to account for 75% of annual positive samples, with each component month defined as an epidemic month. Furthermore, we modelled monthly AAP of influenza virus and respiratory syncytial virus using site-specific temperature and relative humidity for the prediction of local average epidemic months. We also predicted global epidemic months of influenza virus and respiratory syncytial virus on a 5° by 5° grid. The systematic review in this study is registered with PROSPERO, number CRD42018091628. Findings: We initally identified 37 335 eligible studies. Of 21 065 studies remaining after exclusion of duplicates, 1081 full-text articles were assessed for eligibility, of which 185 were identified as eligible. We included 246 sites for influenza virus, 183 sites for respiratory syncytial virus, 83 sites for parainfluenza virus, and 65 sites for metapneumovirus. Influenza virus had clear seasonal epidemics in winter months in most temperate sites but timing of epidemics was more variable and less seasonal with decreasing distance from the equator. Unlike influenza virus, respiratory syncytial virus had clear seasonal epidemics in both temperate and tropical regions, starting in late summer months in the tropics of each hemisphere, reaching most temperate sites in winter months. In most temperate sites, influenza virus epidemics occurred later than respiratory syncytial virus (by 0·3 months [95% CI −0·3 to 0·9]) while no clear temporal order was observed in the tropics. Parainfluenza virus epidemics were found mostly in spring and early summer months in each hemisphere. Metapneumovirus epidemics occurred in late winter and spring in most temperate sites but the timing of epidemics was more diverse in the tropics. Influenza virus epidemics had shorter duration (3·8 months [3·6 to 4·0]) in temperate sites and longer duration (5·2 months [4·9 to 5·5]) in the tropics. Duration of epidemics was similar across all sites for respiratory syncytial virus (4·6 months [4·3 to 4·8]), as it was for metapneumovirus (4·8 months [4·4 to 5·1]). By comparison, parainfluenza virus had longer duration of epidemics (6·3 months [6·0 to 6·7]). Our model had good predictability in the average epidemic months of influenza virus in temperate regions and respiratory syncytial virus in both temperate and tropical regions. Through leave-one-out cross validation, the overall prediction error in the onset of epidemics was within 1 month (influenza virus −0·2 months [−0·6 to 0·1]; respiratory syncytial virus 0·1 months [−0·2 to 0·4]). Interpretation: This study is the first to provide global representations of month-by-month activity of influenza virus, respiratory syncytial virus, parainfluenza virus, and metapneumovirus. Our model is helpful in predicting the local onset month of influenza virus and respiratory syncytial virus epidemics. The seasonality information has important implications for health services planning, the timing of respiratory syncytial virus passive prophylaxis, and the strategy of influenza virus and future respiratory syncytial virus vaccination. Funding: European Union Innovative Medicines Initiative Respiratory Syncytial Virus Consortium in Europe (RESCEU)

Uso del ELISA de captura de antígeno en el monitoreo de porcinos infectados naturalmente con Cysticercus cellulosae y tratados con oxfendazol

La Cisticercosis por Tenia solium es una enfermedad zoonótica común en países en desarrollo y un grave problema de salud pública a nivel mundial. En la actualidad es posible tratarla mediante el uso de cisticidas, pero una vez aplicado el tratamiento el monitoreo de la evolución del animal es limitado por el alto costo de las técnicas de radioimagen. Las pruebas diagnosticas disponibles no son útiles en el monitoreo pues detectan la presencia de anticuerpos contra los C. cellulosae, los cuales se mantienen en circulación aun después de muertos los quistes. Por ello, el objetivo del presente estudio fue demostrar la utilidad del ELISA captura de antígeno en el monitoreo de la persistencia de antígeno parasitario circulante en animales tratados contra cisticercosis. Para este fin, se tomó un grupo de sueros que corresponden al seguimiento pre y post tratamiento de 6 cerdos naturalmente infectados con cisticercosis y tratados con oxfendazol. Se utilizó también el archivo de necropsias y las fichas de evaginación. Se encontró que el tiempo en el que los títulos de antígeno fueron inferiores al punto de corte ocurrió el día 59 post tratamiento y la media de supervivencia fue de 71.5 (59.25 – 83.75) días, también que los animales con escasa carga parasitaria poseen escasa cantidad de antígeno parasitario final. Este resultado demostró que el ELISA – Ag permitiría el monitoreo cuantitativo del comportamiento y persistencia de los antígenos circulantes en animales infectados naturalmente y tratados con una droga cisticida. Finalmente se recomienda el uso de esta prueba en el monitoreo de tratamientos a humanos.-- Taenia solium cysticercosis is a serious public health problem in developing countries. At the present time it is possible to treat this disease using antiparasitic drugs, but once the treatment is administered, monitoring the disease status of animals is limited by the high cost of radiological techniques. Currently available diagnostic assays are not useful in this respect because they detect the presence of antibodies against the C. cellulosae, which are still in circulation after the cysts have died. The objective of the present study was to demonstrate the utility of a monoclonal antibody-based capture ELISA (Ag-ELISA) in the monitoring of the persistence of circulating parasite antigens in animals treated for cysticercosis. Serum samples of six pigs naturally infected with cysticercosis and treated with oxfendazol were evaluated both before and after treatment. Records of necropsies and evagination tests were also used. It was found that the time for antigen titres to fall to less than the cut off ELISA optical density (OD) occurred on day 59 post-treatment and the mean survival time of C. cellulosae antigens as determined by Kaplan Meier analysis was 71.5 (59.25–83.75) days. It was also found that animals with a small number of cysts had small quantities of parasite antigen. This result demonstrated that this Ag–ELISA would allow the quantitative monitoring of the persistence of circulating antigens of C.cellulosae in animals infected naturally and treated with an antiparasitic drug. Finally, the use of this assay is recommended in the monitoring of human cysticercosis treatment.Tesi

USO DEL ELISA DE CAPTURA DE ANTÍGENO EN EL MONITOREO DE PORCINOS INFECTADOS NATURALMENTE CON Cysticercus cellulosae Y TRATADOS CON OXFENDAZOL

Taenia solium cysticercosis is a serious public health problem in developing countries around the world. At the present time, treatment with anthelmintic drugs is possible, but once applied the treatment the monitoring of the animal is limited by the high cost of the radiological techniques. Moreover, the available immunodiagnostic assays are not useful for monitoring because they detect the presence of antibodies against C. cellulosae, which remain in circulation after cysts are dead. The objective of the present study was to demonstrate the usefulness of a monoclonal antibody-based capture ELISA (AgELISA) in the monitoring of the persistence of circulating parasite antigens in animals treated against cysticercosis. For this purpose, serum samples corresponding to the monitoring of pre and post treatment of 6 pigs, naturally infected with cysticercosis and treated with oxfendazol, were evaluated. Necropsy data and evagination records were also used. It was found that the time in which the antigen titles were lower to the cut off OD values occurred on day 59 post treatment and that the mean survival time was 71.5 (59.3-83.8) days. These results seem to demonstrate that the Ag-ELISA would allow the quantitative monitoring of the behavior and persistence of circulating antigens in naturally infected animals that are treated with an antiparasitic drug. However, the monitoring of additional treated pigs are required to obtain conclusive results.La cisticercosis por Taenia solium es una enfermedad zoonótica común en países en desarrollo y un grave problema de salud pública a nivel mundial. En la actualidad es posible tratarla mediante el uso de cisticidas, pero una vez aplicado el tratamiento, el monitoreo de la evolución del animal es limitado por el alto costo de las técnicas de radioimagen. Además, las pruebas inmunodiagnósticas disponibles no son útiles en el monitoreo pues detectan la presencia de anticuerpos contra los C. cellulosae, los cuales se mantienen en circulación, aún después de la muerte de los quistes. Por ello, el objetivo del presente estudio fue demostrar la utilidad del ELISA captura de antígeno en el monitoreo de la persistencia de antígeno parasitario circulante en animales tratados contra cisticer-cosis. Para este fin, se tomó un grupo de sueros que corresponden al seguimiento pre y post tratamiento de 6 cerdos naturalmente infectados con cisticercosis y tratados con oxfendazol. Se utilizó también el archivo de necropsias y las fichas de evaginación. Se encontró que el tiempo en el que los títulos de antígeno fueron inferiores al punto de corte ocurrió en el día 59 post tratamiento y que la media de supervivencia fue de 71.5 días (59.3-83.8). Los resultados parecen evidenciar que el ELISA-Ag permitiría el monitoreo cuantitativo del comportamiento y persistencia de los antígenos circulantes en animales naturalmente infectados y tratados con una droga cisticida. Sin embargo, se requiere monitorear mayor cantidad de cerdos para obtener resultados concluyentes

Nested PCR for Specific Diagnosis of Taenia solium Taeniasis▿

Taeniasis due to Taenia solium is a disease with important public health consequences, since the larval stage is not exclusive to the animal intermediate, the pig, but also infects humans, causing neurocysticercosis. Early diagnosis and treatment of T. solium tapeworm carriers is important to prevent human cysticercosis. Current diagnosis based on microscopic observation of eggs lacks both sensitivity and specificity. In the present study, a nested-PCR assay targeting the Tso31 gene was developed for the specific diagnosis of taeniasis due to T. solium. Initial specificity and sensitivity testing was performed using stored known T. solium-positive and -negative samples. The assay was further analyzed under field conditions by conducting a case-control study of pretreatment stool samples collected from a population in an area of endemicity. Using the archived samples, the assay showed 97% (31/32) sensitivity and 100% (123/123) specificity. Under field conditions, the assay had 100% sensitivity and specificity using microscopy/enzyme-linked immunosorbent assay coproantigen testing as the gold standards. The Tso31 nested PCR described here might be a useful tool for the early diagnosis and prevention of taeniasis/cysticercosis