sábado, 23 de mayo de 2015

Ofidismo y Escorpionismo en Brazil 2015 Plos NTD

Snakebites and Scorpion Stings in the Brazilian Amazon: Identifying Research Priorities for a Largely Neglected Problem

Envenomings by snakebites and scorpion stings impose a high burden worldwide and result in considerable social and economic impact [1]. It is estimated that snakebite rates are as high as over 1.8 million cases per year, with associated deaths reaching more than 90,000 cases annually [2]. However, snakebites are a neglected condition with no associated WHO programmes for control and prevention. The countries most affected by snakebites are located in the intertropical zone in areas with high rates of field use for agriculture where the main affected populations are adult men working in agricultural activities [1]. Approximately two billion people are living in areas at risk for scorpion stings, with over one million accidents occurring annually worldwide [3]. However, the true burden of snakebites and scorpion stings is probably higher and difficult to estimate since only a few countries have a reliable system for epidemiological surveillance of these events.
In Brazil, the Ministry of Health implemented the National Program for Snakebites Control in 1986, extended to other poisonous animals in 1988. Since then, antivenom (AV) production has been standardized and all the AV production from the three national laboratories (Instituto Butantan, Fundação Ezequiel Dias, and Instituto Vital Brazil) was acquired by the Ministry of Health for distribution free of charge to patients. Five types of snake AVs are currently available: Bothrops AV (main one), Crotalus AV, Bothrops-Crotalus AV, Bothrops-Lachesis AV, and Micrurus AV. For scorpion stings, there are two types of AVs available in Brazil: Tityus scorpion AV and a polyvalent AV against Loxosceles and Phoneutria spiders and the Tityus scorpion. Table 1 summarizes information on snake and scorpion AVs produced in Brazil.
In 2013, 27,181 and 78,091 cases of snakebites and scorpion stings were reported by the Brazilian Ministry of Health, respectively [4]. The highest incidence was in the North region (52.6 cases/100,000 inhabitants) followed by the Midwest (16.4/100,000). These values, expected to be higher in remote areas of the Brazilian Amazon [5], may be underestimated due to considerable underreporting. Fig 1 presents the spatial distribution of snakebites and scorpion stings in the Brazilian Amazon.

lunes, 18 de mayo de 2015

Eliminación de malaria en la Amazonia (Publicación)

Modelling the potential of focal screening and treatment as elimination strategy for Plasmodium falciparum malaria in the Peruvian Amazon Region.

Abstract

BACKGROUND:

Focal screening and treatment (FSAT) of malaria infections has recently been introduced in Peru to overcome the inherent limitations of passive case detection (PCD) and further decrease the malaria burden. Here, we used a relatively straightforward mathematical model to assess the potential of FSAT as elimination strategy for Plasmodium falciparum malaria in the Peruvian Amazon Region.

METHODS:

A baseline model was developed to simulate a scenario with seasonal malaria transmission and the effect of PCD and treatment of symptomatic infections on the P. falciparum malaria transmission in a low endemic area of the Peruvian Amazon. The model was then adjusted to simulate intervention scenarios for predicting the long term additional impact of FSAT on P. falciparum malaria prevalence and incidence. Model parameterization was done using data from a cohort study in a rural Amazonian community as well as published transmission parameters from previous studies in similar areas. The effect of FSAT timing and frequency, using either microscopy or a supposed field PCR, was assessed on both predicted incidence and prevalence rates.

RESULTS:

The intervention model indicated that the addition of FSAT to PCD significantly reduced the predicted P. falciparum incidence and prevalence. The strongest reduction was observed when three consecutive FSAT were implemented at the beginning of the low transmission season, and if malaria diagnosis was done with PCR. Repeated interventions for consecutive years (10 years with microscopy or 5 years with PCR), would allow reaching near to zero incidence and prevalence rates.

CONCLUSIONS:

The addition of FSAT interventions to PCD may enable to reach P. falciparum elimination levels in low endemic areas of the Amazon Region, yet the progression rates to those levels may vary substantially according to the operational criteria used for the intervention.