Enhanced health facility surveys to support malaria control and elimination across different transmission settings in the Philippines

Following substantial progress in malaria control in the Philippines, new surveillance approaches are needed to identify and target residual malaria transmission. This study evaluated an enhanced surveillance approach using rolling cross-sectional surveys of all health facility attendees augmented with molecular diagnostics and geolocation. Facility surveys were carried out in three sites representing different transmission intensities: Morong, Bataan (pre-elimination), Abra de Ilog, Occidental Mindoro (stable medium risk), and Rizal, Palawan (high risk, control). Only one rapid diagnostic test (RDT)–positive infection and no PCR confirmed infections were found in Bataan and Occidental Mindoro, suggesting the absence of transmission. In Palawan, the inclusion of all health facility attendees, regardless of symptoms, and use of molecular diagnostics identified 313 infected individuals in addition to 300 cases identified by routine screening of febrile patients with the RDT or microscopy. Of these, the majority (313/613) were subpatent infections and only detected using molecular methods. Simultaneous collection of GPS coordinates on tablet-based applications allowed real-time mapping of malaria infections. Risk factor analysis showed higher risks in children and indigenous groups, with bed net use having a protective effect. Subpatent infections were more common in men and older age-groups. Overall, malaria risks were not associated with participants’ classification, and some of the non-patient clinic attendees reported febrile illnesses (1.9%, 26/1,369), despite not seeking treatment, highlighting the widespread distribution of infection in communities. Together, these data illustrate the utility of health facility–based surveys to augment surveillance data to increase the probability of detecting infections in the wider community

Enhanced health facility surveys to support malaria control and elimination across different transmission settings in The Philippines

Abstract Following substantial progress in malaria control in the Philippines, new surveillance approaches are needed to identify and target residual malaria transmission. This study evaluated an enhanced surveillance approach using rolling cross-sectional surveys of all health facility attendees augmented with molecular diagnostics and geolocation. Facility surveys were carried out in 3 sites representing different transmission intensities: Morong, Bataan (pre-elimination), Abra de Ilog, Occidental Mindoro (stable-medium risk) and Rizal, Palawan (high risk, control). Only 1 RDT positive infection and no PCR confirmed infections were found in Bataan and Occidental Mindoro suggesting the absence of transmission. In Rizal, inclusion of all health facility attendees, regardless of symptoms, and use of molecular diagnostics identified an additional 313 infected individuals in addition to 300 cases identified by routine screening of febrile patients with RDT or microscopy. Of these, the majority (313/613) were subpatent infections and only detected using molecular methods. Simultaneous collection of GPS coordinates on tablet-based applications allowed real-time mapping of malaria infections. Risk factor analysis showed higher risks in children and indigenous groups, with bednet use having a protective effect. Subpatent infections were more common in men and older age groups. Overall, malaria risks were not associated with patient status and some of non-patient clinic attendees reported febrile illnesses (1.9%, 26/1369) despite not seeking treatment highlighting the widespread distribution of infection in communities. Together, these data illustrate the utility of health-facility based surveys to augment surveillance data to increase the probability of detecting infections in the wider community

VTPin: Practical VTable hijacking protection for binaries

VTable hijacking has lately been promoted to the de facto technique for exploiting C++ applications, and in particular web browsers. VTables, however, can be manipulated without necessarily corrupting memory, simply by leveraging use-after-free bugs. In fact, in the recent Pwn2Own competitions all major web browsers were compromised with exploits that employed (among others) use-afterfree vulnerabilities and VTable hijacking. In this paper, we propose VTPin: a system to protect against VTable hijacking, via use-after-free vulnerabilities, in large C++ binaries that cannot be re-compiled or re-written. The main idea behind VTPin is to pin all the freed VTable pointers on a safe VTable under VTPin's control. Specifically, for every object deallocation, VTPin deallocates all space allocated, but preserves and updates the VTable pointer with the address of the safe VTable. Hence, any dereferenced dangling pointer can only invoke a method provided by VTPin's safe object. Subsequently, all virtual-method calls due to dangling pointers are not simply neutralized, but they can be logged, tracked, and patched. Compared to other solutions that defend against VTable hijacking, VTPin exhibits certain characteristics that make it suitable for practical and instant deployment in production software. First, VTPin protects binaries, directly and transparently, without requiring source compilation or binary rewriting. Second, VTPin is not an allocator replacement, and thus it does not interfere with the allocation strategies and policies of the protected program; it intervenes in the deallocation process only when a virtual object is to be freed for preserving the VTable pointer. Third, VTPin is fast; Mozilla Firefox, protected with VTPin, experiences an average overhead of 1%-4.1% when running popular browser benchmarks