SUMMARY
# Viral Infections and Alzheimer's Disease — causal mechanisms and therapeutic implications
## Background and Rationale
Alzheimer's disease (AD) affects over 50 million people worldwide, yet its etiology remains incompletely understood. Emerging evidence suggests viral infections, particularly herpes simplex virus type 1 (HSV-1) and human herpesvirus 6 (HHV-6), may contribute to AD pathogenesis through neuroinflammation, direct neuronal damage, and acceleration of amyloid-beta and tau pathology.
METHODOLOGY NOTES
Phase 1 (Months 0-6): Recruit 1,200 participants across three cognitive groups through memory clinics and population registries. Obtain informed consent, medical history, and baseline assessments including MMSE, CDR, and neuropsychological battery. Collect blood, saliva, and cerebrospinal fluid samples. Perform HSV-1 and HHV-6 serology (IgG, IgM) using ELISA and chemiluminescence assays. Conduct qPCR for viral DNA detection in plasma and CSF using custom primers. Measure CSF biomarkers (Aβ42, p-tau181, t-tau, NFL) via Lumipulse platform. Perform structural MRI and amyloid PET imaging using standardized protocols. Phase 2 (Months 6-30): Conduct quarterly follow-up visits with cognitive assessments, viral reactivation monitoring through saliva HSV-1 shedding detection, and semi-annual biomarker collection. Implement nested RCT randomizing 400 HSV-positive participants to valacyclovir 1g BID versus placebo. Monitor adherence via pill counts and drug levels. Assess safety through liver fun