Activity of Propolis Nanoparticles against HSV-2: Promising Approach to Inhibiting Infection and Replication.

Herpes simplex type 2 (HSV-2) infection causes a significant life-long disease. Long-term side effects of antiviral drugs can lead to the emergence of drug resistance. Thus, propolis, a natural product derived from beehives, has been proposed to prevent or treat HSV-2 infections. Unfortunately, therapeutic applications of propolis are still limited due its poor solubility. To overcome this, a nanoparticle-based drug delivery system was employed. An ethanolic extract of propolis (EEP) was encapsulated in nanoparticles composed of poly(lactic-co-glycolic acid) and chitosan using a modified oil-in-water single emulsion by using the solvent evaporation method. The produced nanoparticles (EEP-NPs) had a spherical shape with a size of ~450 nm and presented satisfactory physicochemical properties, including positively charged surface (38.05 ± 7.65 mV), high entrapment efficiency (79.89 ± 13.92%), and sustained release profile. Moreover, EEP-NPs were less cytotoxic on Vero cells and exhibited anti-HSV-2 activity. EEP-NPs had a direct effect on the inactivation of viral particles, and also disrupted the virion entry and release from the host cells. A significant decrease in the expression levels of the HSV-2 replication-related genes (ICP4, ICP27, and gB) was also observed. Our study suggests that EEP-NPs provide a strong anti-HSV-2 activity and serve as a promising platform for the treatment of HSV-2 infections.

Antibody response to rabies pre-exposure vaccination among village health volunteers in a northern region of Thailand.

BACKGROUND: Rabies is a lethal, however the disease is preventable through vaccination either before or immediately after an exposure. This study aimed to provide a pre-exposure prophylaxis rabies immunization to village health volunteers (VHV) who provide rabies vaccination for pets and free-roaming dogs in their villages and evaluate the antibody level and adverse effects after vaccination. We also assessed the knowledge related to rabies of these VHVs before field trip for pet vaccination. METHODS: This study was conducted at Mae Kha sub district, San Pa Tong district, Chiangmai, Thailand between January and March 2020. Consenting participants were interviewed using a questionnaire, received an intradermal two-dose, seven-day pre-exposure rabies vaccination, and sera were tested for anti-rabies antibody levels with the cost effective easy competitive enzyme-linked immunosorbent assay (CEE-cELISA) before and after vaccination. RESULTS: A total of 27 VHVs were recruited from 14 villages in Mae Kha sub district. All of them were male and had a median age of 61.5 years (interquartile range: 55-64). After vaccination, seroconversion rate was 92 % (23/25) with a median of 12.4 EU/mL (interquartile range: 8.9-20.1). Two participants who had rabies vaccination one year previously still had adequate levels before receiving a booster dose. All participants did not show any serious adverse reactions after vaccination. CONCLUSION: A regimen of two-dose, seven-day vaccination series in high-risk health volunteers using an intradermal administration provides a high seroconversion rate, efficacy and safe for pre-exposure vaccination schedule. In addition, rabies-related knowledge should be provided to village health volunteers before their fieldwork.

Lack of Association between Adverse Pregnancy Outcomes and Zika Antibodies among Pregnant Women in Thailand between 1997 and 2015.

Data about Zika virus infection and adverse pregnancy outcomes in Southeast Asia are scarce. We conducted an unmatched case-control study of Zika virus (ZIKV) serology in pregnant women enrolled in human immunodeficiency virus (HIV) or hepatitis B virus (HBV) perinatal prevention trials between 1997 and 2015 in Thailand. Case and control groups included women with and without adverse pregnancy outcomes. Plasma samples collected during the last trimester of pregnancy were tested for ZIKV IgG/IgM and Dengue IgG/IgM (Euroimmun, AG, Germany). Case newborn plasma samples were tested for ZIKV IgM and ZIKV RNA (Viasure, Spain). The case group included women with stillbirth (n = 22) or whose infants had microcephaly (n = 4), a head circumference below the first percentile (n = 14), neurological disorders (n = 36), or had died within 10 days after birth (n = 11). No women in the case group were positive for ZIKV IgM, and none of their live-born neonates were positive for ZIKV IgM or ZIKV RNA. The overall ZIKV IgG prevalence was 29%, 24% in the case and 34% in the control groups (Fisher's exact test; p = 0.13), while the dengue IgG seroprevalence was 90%. Neither neonatal ZIKV infections nor ZIKV-related adverse pregnancy outcomes were observed in these women with HIV and/or HBV during the 18-year study period.

Causes of Hypertensive Anterior Uveitis in Thailand.

PURPOSE: To determine the prevalence of viral infections in patients with hypertensive anterior uveitis in Thailand from polymerase chain reaction (PCR) of aqueous humor. METHODS: Thirty-one patients with anterior uveitis with intraocular pressure (IOP) above 25 mmHg were included for PCR analysis for cytomegalovirus (CMV), herpes simplex (HSV), varicella-zoster (VZV), rubella, chikungunya and Zika virus. RESULTS: The prevalence of PCR-positive results was 32%, including 19% for CMV, 10% for HSV, and 3% for VZV; PCR for other tested viruses demonstrated negative results. PCR-positive patients exhibited satisfactory IOP control with antiviral and anti-glaucomatous treatment compared to PCR-negative patients, and more than half of PCR-negative patients required glaucoma surgery within 12 months (P = .01). CONCLUSION: PCR evidence of infection with herpes group viruses was found in one-third of patients with hypertensive anterior uveitis; CMV being the most common pathogen. The PCR-positive group generally responded well to a combination of antiviral and anti-glaucoma treatment.

Genetic analyses of HIV env associated with uveitis in antiretroviral-naive individuals.

OBJECTIVE: To analyze and compare HIV-1 env sequences from the eye to those from the blood of individuals with uveitis attributed to HIV with the goal of gaining insight into the pathogenesis of HIV-associated eye disease. DESIGN: A prospective case series of five HIV-infected antiretroviral-naive individuals with uveitis negative for other pathogens. METHODS: RNA from blood plasma and ocular aqueous humor was reverse transcribed using random hexamers. HIV env C2-V5 (HXB2: 6990-7668) sequences were generated by single-genome amplification using nested polymerase chain reaction followed by bidirectional Sanger sequencing. Sequence analyses by Geneious, Geno2Pheno, N-GLYCOSITE, DIVEIN, and HyPhy evaluated relationships between HIV in plasma and aqueous humor. RESULTS: A median of 20 (range: 13-22) plasma and 15 (range: 9-18) aqueous humor sequences were generated from each individual. The frequencies of sequences with predicted-N-linked-glycosylation sites and C-X-C chemokine receptor type 4 were comparable in aqueous humor and plasma of all five patients. Aqueous humor sequences had lower median genetic diversity compared with plasma across all patients, but similar divergence, in four of five patients. Aqueous humor HIV sequences were compartmentalized from plasma across subjects by Critchlow correlation coefficient, Slatkin and Maddison, nearest-neighbor statistic, and Fixation index. CONCLUSION: Among antiretroviral-naive individuals with uveitis attributed to HIV, the universal compartmentalization and decreased diversity of eye compared with blood sequences suggests time-limited passage of a small subset of variants from each patient's viral population into the eye tissues, followed by limited immune selection despite the inflammatory uveitis.

Clinical manifestations of cytomegalovirus-associated posterior uveitis and panuveitis in patients without human immunodeficiency virus infection.

IMPORTANCE: Little attention has been paid to clinical features of cytomegalovirus (CMV) infections in individuals without human immunodeficiency virus (HIV). OBJECTIVE: To describe the clinical manifestations and comorbidities of patients without HIV infection who have CMV-associated posterior uveitis or panuveitis. DESIGN AND SETTING: Retrospective observational case series in an academic research setting. PARTICIPANTS: The medical records were reviewed of 18 patients (22 affected eyes) diagnosed as having posterior uveitis or panuveitis who had aqueous positive for CMV by polymerase chain reaction techniques. MAIN OUTCOME MEASURES: Demographic data, clinical manifestations, and associated systemic diseases were recorded. RESULTS: Ocular features included focal hemorrhagic retinitis (n = 13) and peripheral retinal necrosis (n = 7). Two eyes had no focal retinal lesions but manifested vasculitis and vitritis. All patients exhibited vitreous inflammation. Inflammatory reactions in anterior segments developed in 14 of 22 eyes (64%). Retinal vasculitis was observed in 16 of 22 eyes (73%) and included mostly arteries (in 13 of 16 eyes [81%]). Eleven of 18 patients were taking immunosuppressive medications (5 for hematologic malignant diseases, 4 for systemic autoimmune diseases, and 2 following organ transplants). One additional patient was diagnosed as having non-Hodgkin lymphoma 3 months after the onset of CMV-associated panuveitis, and another patient had primary immunodeficiency disorder. Of the remaining 5 patients, 2 had diabetes mellitus, and 3 had no associated systemic diseases and exhibited no evidence of immune deficiency. CONCLUSIONS AND RELEVANCE: Cytomegalovirus-associated infections of posterior eye segments can develop in patients without HIV infection who have compromised immune function of variable severity but may occur also in individuals who have no evidence of immune insufficiency. Cytomegalovirus infections located in posterior eye segments in patients without HIV infection caused intraocular inflammatory reaction in all cases and demonstrated more variable clinical presentation than classic CMV retinitis observed in patients with HIV infection.

Infectious causes of posterior uveitis and panuveitis in Thailand.

PURPOSE: To determine the infectious causes of posterior uveitis (PU) and panuveitis (panU) in Thailand. METHODS: We investigated the infectious causes of uveitis involving the posterior segment of the eye by using real-time polymerase chain reaction (PCR) for cytomegalovirus (CMV), herpes simplex virus (HSV-1, HSV-2), varicella zoster virus and Toxoplasma gondii (T. gondii) DNA in intraocular samples of 80 human immunodeficiency virus (HIV)-negative patients. Additionally, in 61 patients, we performed Goldmann-Witmer coefficient (GWC) analysis for T. gondii. RESULTS: Twenty-four (30 %) patients with PU and/or panU had a positive PCR result. Overall, CMV was the most frequently identified organism. While CMV was the most common cause of uveitis in the patients on immunosuppressive medications for nonocular disorders, HSV was the most common cause of posterior and panuveitis in the patients not receiving such medication. In 38 PU patients, CMV was the most common detected pathogen. In 42 panU patients, CMV and HSV-2 were the most frequently identified pathogens. Out of 61 paired samples analyzed for T. gondii by GWC analysis, only 1 revealed a positive result. There was no difference in PCR results between aqueous humor and vitreous samples. CONCLUSIONS: CMV was the most frequently identified infectious organism in posterior and panuveitis of HIV-1-negative Thai patients. Aqueous humor and vitreous samples showed similar diagnostic values in PCR analysis.

The diagnostic value of intraocular fluid analysis by polymerase chain reaction in Thai patients with uveitis.

Uveitis is a major cause of severe visual impairment throughout the world and can be initiated by various infectious and non-infectious causes. Early recognition of specific infections is important as the treatment with antimicrobial agents might stop the progression or even cure the eye disease. To determine the infectious causes of uveitis in Thailand, intraocular fluid samples of 100 HIV-negative patients and 47 HIV-positive patients with uveitis were examined using real-time PCR analysis for herpes simplex virus, varicella zoster virus, cytomegalovirus and Toxoplasma gondii. Positive PCR results were found in 33/100 (33%) HIV-negative patients and in 33/47 (70%) HIV-positive patients with uveitis. In Thailand, cytomegalovirus was identified as the most frequent cause of infectious uveitis in both HIV-negative and HIV-positive patients (49 and 91%, respectively). PCR analysis of intraocular samples in uveitis was a valuable diagnostic assay. The pattern of uveitis observed in the Far East differs from that found in the West.

Intraocular and plasma HIV-1 RNA loads and HIV uveitis.

OBJECTIVE: The objective of this study was to analyze human immunodeficiency virus (HIV) dynamics across the blood-retinal barrier and to determine whether the high levels of HIV in the eye are associated with any ocular disorders in HIV-infected patients. DESIGN: This study included a prospective case series of 40 HIV-positive patients with uveitis. INTERVENTION: Clinical and laboratory examinations included plasma and intraocular HIV-1 RNA loads as well as the clinical manifestations of uveitis. RESULTS: Intraocular HIV-1 RNA was detected in 32% (13/40) of HIV-positive patients with uveitis. Intraocular HIV-1 RNA loads were associated with high HIV-1 RNA plasma loads (P < 0.001) and not being on HAART therapy (P = 0.005). In addition, detectable intraocular HIV-1 RNA levels were higher in patients with the absence of retinal lesions (P = 0.008). In three patients, the HIV load in the eye largely exceeded that of plasma. These three patients had all bilateral anterior uveitis and/or vitritis without retinal lesions and exhibited no evidence of other intraocular infectious agents causing uveitis than HIV itself. CONCLUSION: The eye can form a sanctuary where HIV might replicate and cause an inflammatory reaction.

Infectious uveitis in Thailand: serologic analyses and clinical features.

PURPOSE: To determine the seroprevalence of various infectious agents in Thai patients with uveitis. METHODS: Prospective study of 101 consecutive patients with uveitis, 100 HIV-infected retinitis patients, and 100 nonuveitis controls. RESULTS: Antibodies against T. gondii were detected in 31/101 non-HIV patients, mostly with posterior uveitis and focal retinitis, and were significantly higher than in other groups examined. Antibodies for T. pallidum and Leptospira were observed more frequently in patients with HIV-infected retinitis. Active tuberculosis in non-HIV patients was not found. CONCLUSIONS: Seroprevalence of T. gondii antibodies in patients with non-HIV posterior uveitis was higher than in nonuveitis controls and HIV patients with retinitis.