Association between quantitative varicella-zoster virus antibody levels and zoster reactivation in HIV-infected persons.

BACKGROUND: Varicella-zoster virus (VZV) reactivation is common but difficult to predict in HIV-infected persons. OBJECTIVE: Since qualitative VZV antibodies can determine past VZV disease or vaccination, we evaluated whether quantitative VZV antibody levels over time can predict future zoster. STUDY DESIGN: US Military HIV Natural History (NHS) participants with a zoster diagnosis at least 5 years after HIV diagnosis (n = 100) were included. Zoster-negative controls (n = 200) were matched by age, race, gender, and CD4 count at HIV diagnosis. Repository plasma specimens collected at baseline and prior to zoster diagnosis were evaluated using a quantitative anti-VZV ELISA assay. Differences in quantitative VZV levels were analyzed by Wilcoxon Mann-Whitney and Fisher's exact tests. RESULTS: Median CD4 count at HIV diagnosis was similar for cases and controls (535 [IQR 384-666] vs. 523 [IQR 377-690] cells/µL; p = 0.940), but lower for cases at zoster diagnosis (436 [IQR 277-631] vs. 527 [IQR 367-744] cells/µL; p = 0.007). Antiretroviral therapy (ART) use prior to zoster diagnosis was lower for cases (52.0%) compared to controls (64.5%; p = 0.025). Cases had similar mean VZV antibody levels prior to zoster diagnosis compared to controls [2.25 ± 0.85 vs. 2.44 ± 0.96 index value/optical density (OD) ratio; p = 0.151] with no difference in the change in antibody levels over time (0.08 ± 0.71 vs. 0.01 ± 0.94 index value/OD per year; p = 0.276). CONCLUSION: Quantitative VZV antibody levels are stable in HIV-infected persons and do not predict zoster reactivation. Low CD4 count and lack of ART use appear to be better predictors of future zoster diagnosis.

Characterizing the Association Between Alcohol and HIV Virologic Failure in a Military Cohort on Antiretroviral Therapy.

BACKGROUND: The effects of at-risk drinking on HIV infection remain controversial. We investigated the impact of self-reported alcohol consumption on surrogate markers of HIV progression among individuals initiated on highly active antiretroviral therapy (HAART). METHODS: We analyzed individuals who were surveyed on alcohol use within a year of HAART initiation between 2006 and 2014. At-risk drinking was defined as consumption of at least 3 or 4 drinks/d, or 7 and 14 drinks/wk among women and men, respectively. We performed time-updated generalized estimating equation logistic regression to determine the effect of at-risk drinking on virologic failure (VF) and mixed-effects linear regression on CD4 count reconstitution, controlling for potential confounders. RESULTS: Of 801 individuals initiated on HAART, 752 individuals with alcohol survey data were included in the analysis. Of these, 45% (n = 336) met criteria for at-risk drinking at HAART initiation on at least 1 survey. The rates of VF were 4.30 per 100 person-years (95% CI [2.86, 6.21]) for at-risk drinkers and 2.45 per 100 person-years (95% CI [1.57, 3.65]) for individuals without at-risk drinking. At-risk drinking was not significantly associated with VF (OR 1.73, 95% CI [0.92, 3.25]) (p = 0.087) or CD4 reconstitution (CD4 increase 11.4; 95% CI [-19.8, 42.7]) in univariate analyses; however, in our multivariate model, a statistically significant relationship between VF and at-risk drinking was observed (OR 2.28, 95% CI [ 1.01, 5.15]). CONCLUSIONS: We found a high proportion of at-risk drinking in our military cohort, which was predictive of VF in multivariate analysis. Given alcohol's effect on myriad HIV and non-HIV outcomes, interventions to decrease the prevalence of at-risk drinking among HIV-infected individuals are warranted.

Factors associated with HIV viral load "blips" and the relationship between self-reported adherence and efavirenz blood levels on blip occurrence: a case-control study.

BACKGROUND: The uncertain etiology of HIV viral load (VL) blips may lead to increased use of clinical resources. We evaluated the association of self-reported adherence (SRA) and antiretroviral (ART) drug levels on blip occurrence in US Military HIV Natural History Study (NHS) participants who initiated the single-tablet regimen efavirenz/emtricitabine/tenofovir disoproxil fumarate (EFV/FTC/TDF). METHODS: ART-naïve NHS participants started on EFV/FTC/TDF between 2006 and 2013 who achieved VL suppression (<50 copies/mL) within 12 months and had available SRA and stored plasma samples were included. Participants with viral blips were compared with those who maintained VL suppression without blips. Untimed EFV plasma levels were evaluated on consecutive blip and non-blip dates by high performance liquid chromatography, with a level ≥1 mcg/mL considered therapeutic. SRA was categorized as ≥85 or <85 %. Descriptive statistics were performed for baseline characteristics and univariate and multivariate Cox proportional hazard models were used to assess the relationship between covariates and blip occurrence. RESULTS: A total of 772 individuals met inclusion criteria, including 99 (13 %) blip and 673 (87 %) control participants. African-American was the predominant ethnicity and the mean age was 29 years for both groups. SRA ≥ 85 % was associated with therapeutic EFV levels at both blip and non-blip time points (P = 0.0026); however no association was observed between blips and SRA or EFV levels among cases. On univariate analysis of cases versus controls, blips were associated with higher mean pre-treatment VL (HR 1.45, 95 % CI 1.11-1.89) and pre-treatment CD4 count <350 cells/µL (68.1 vs 49.7 %). Multivariate analysis also showed that blips were associated with a higher mean VL (HR 1.42, 95 % CI 1.08-1.88; P = 0.0123) and lower CD4 count at ART initiation, with CD4 ≥500 cells/µL having a protective effect (HR 0.45, 95 % CI 0.22-0.95; P = 0.0365). No association was observed for demographic characteristics or SRA. CONCLUSION: Blips are commonly encountered in the clinical management of HIV-infected patients. Although blip occurrence was not associated with SRA or EFV blood levels in our study, blips were associated with HIV-related factors of pre-ART high VL and low CD4 count. Additional studies are needed to determine the etiology of blips in HIV-infected patients.

A single dose of benzathine penicillin G is as effective as multiple doses of benzathine penicillin G for the treatment of HIV-infected persons with early syphilis.

BACKGROUND: Treatment guidelines recommend the use of a single dose of benzathine penicillin G (BPG) for treating early syphilis in human immunodeficiency virus (HIV)-infected persons. However, data supporting this recommendation are limited. We examined the efficacy of single-dose BPG in the US Military HIV Natural History Study. METHODS: Subjects were included if they met serologic criteria for syphilis (ie, a positive nontreponemal test [NTr] confirmed by treponemal testing). Response to treatment was assessed at 13 months and was defined by a ≥4-fold decline in NTr titer. Multivariate Cox proportional hazard regression models were utilized to examine factors associated with treatment response. RESULTS: Three hundred fifty subjects (99% male) contributed 478 cases. Three hundred ninety-three cases were treated exclusively with BPG (141 with 1 dose of BPG). Treatment response was the same among those receiving 1 or >1 dose of BPG (92%). In a multivariate analysis, older age (hazard ratio [HR], 0.82 per 10-year increase; 95% confidence interval [CI], .73-.93) was associated with delayed response to treatment. Higher pretreatment titers (reference NTr titer <1:64; HR, 1.94 [95% CI, 1.58-2.39]) and CD4 counts (HR, 1.07 for every 100-cell increase [95% CI, 1.01-1.12]) were associated with a faster response to treatment. Response was not affected by the number of BPG doses received (reference, 1 dose of BPG; HR, 1.11 [95% CI, .89-1.4]). CONCLUSIONS: In this cohort, additional BPG doses did not affect treatment response. Our data support the current recommendations for the use of a single dose of BPG to treat HIV-infected persons with early syphilis.

Seroprevalence and seroincidence of herpes simplex virus (2006-2010), syphilis (2006-2010), and vaccine-preventable human papillomavirus subtypes (2000-2010) among US military personnel.

BACKGROUND: Sexually transmitted infections have historically been burdensome in military populations. We describe the seroprevalence and seroincidence of vaccine-preventable human papillomavirus (VP-HPV) subtypes in a sample of 200 servicemen, along with the seroprevalence and seroincidence of herpes simplex virus (HSV-1/2) and syphilis in a sample of 200 men and 200 women. METHODS: Sera from 200 men, along with associated demographic data, were obtained and tested for HPV serotypes at service entry and 10 years later. Similarly, 200 active-duty men and 200 active-duty women were tested for HSV-1/2 at entry to service and 4 years later. RESULTS: The baseline prevalence of VP-HPV subtypes was 14.5%, and cumulative seroincidence of new infection was 34% over a 10-year period (n = 68). Of these, 63% (n = 43) represented HPV-6, HPV-11, or both; 18% of new infections were either HPV-16 or HPV-18, and 19% (n = 13) were a mixture of all 4 strains. At entry to military service, 33.5% of men were seropositive for HSV-1 and 1.5% were positive for HSV-2; seroincidence was 3.4 and 1.1 per 100 person-years, respectively. Among women, 39% were seropositive for HSV-1 and 4.0% for HSV-2; seroincidence was 5.5 and 3.3 per 100 person-years, respectively. There were 2 prevalent and 3 incident cases of syphilis. CONCLUSIONS: Sexually transmitted infections in military populations are highly prevalent, incident, and epidemiologically distinct. Our data show the rates of HPV and HSV-1/2 acquisition that are higher than those seen in the general public, again highlighting the need for continued preventive efforts. Consideration of universal HPV vaccination among men is warranted.

Association between hepatitis B vaccine antibody response and CD4 reconstitution after initiation of combination antiretroviral therapy in HIV-infected persons.

BACKGROUND: Hepatitis B virus (HBV) vaccine antibody response has been associated with reduced risk of AIDS or death. However, it is unknown whether HBV vaccine responsiveness is associated with improved immune reconstitution during treatment with combination antiretroviral therapy (cART). We evaluated the relationship between HBV vaccine response status and CD4 reconstitution on cART in the U.S Military HIV Natural History Study. METHODS: Participants with viral load <400 copies/mL within 1 year on initial cART and documented HBV vaccination and surface antibody (anti-HBs) prior to cART were included. Participants were characterized as HBV vaccine responders (anti-HBs ≥10 IU/L) or non-responders (<10 IU/L) and further divided into 2 groups based on vaccine administration before or after HIV diagnosis. Linear mixed regression was used to model CD4 reconstitution during the first year of cART. RESULTS: Of the 307 and 169 participants vaccinated before or after HIV diagnosis, HBV vaccine response occurred in 288 (94%) and 74 (44%), respectively. For those vaccinated before HIV diagnosis, CD4 counts increased by a median 190 [IQR 99-310] cells/mm(3) for responders and 186 [IQR 116-366] cells/mm(3) for non-responders during the first year (P = 0.684). Participants vaccinated after HIV diagnosis had median increases of 185 [IQR 76-270] and 143 [IQR 47-238] cells/mm(3) for responders and non-responders, respectively (P = 0.134). In contrast to those with CD4 > 350 cells/mm(3) at cART initiation, participants with CD4 < 200 and 200-350 cells/mm(3) had significantly reduced CD4 gains in both groups by longitudinal mixed models, but there was no difference in CD4 recovery according to HBV vaccine seroresponse. CONCLUSIONS: Although HBV vaccine responsiveness is associated with a reduction in HIV disease progression, HBV vaccine responders do not achieve greater CD4 gains during the first year of cART. Additional clinical markers are needed to predict the magnitude of post-cART immune recovery.

A cross-sectional study of low HIV testing frequency and high-risk behaviour among men who have sex with men and transgender women in Lima, Peru.

BACKGROUND: Increased HIV testing frequency among high-risk populations such as men who have sex with men (MSM) and male-to-female transgender women (TW) can lead to earlier treatment and potentially reduce HIV transmission. METHODS: We analyzed baseline survey data from 718 high-risk, young (median age 29 [interquartile range 23-35]) MSM/TW enrolled in a community-based HIV prevention trial between 2008-2009. Participants were recruited from 24 neighborhoods in and around Lima, Peru. We assessed HIV testing frequency, testing behaviour, and motivations and barriers to testing. Multivariate analysis identified correlates to prior HIV testing. RESULTS: Overall, 79.6% reported HIV testing within their lifetimes, however, only 6.2% reported an average of two tests per year, as per Peruvian Ministry of Health guidelines. The most commonly reported motivators for testing were to check one's health (23.3%), lack of condom use (19.7%), and availability of free testing (14.0%), while low self-perceived risk for HIV (46.9%), fear of a positive result (42.0%), and lack of access to testing services (35.7%) were the most frequently reported barriers. In multivariate analysis, factors independently associated with HIV testing included age [adjusted prevalence ratio (APR) 1.00, 95% CI (1.00-1.01)], transgender-identification vs. gay-identification [APR 1.11, 95% CI (1.03-1.20)], history of transactional sex [APR 1.16, 95% CI (1.07-1.27)], and prior sexually transmitted infection diagnosis [APR 1.15, 95% CI (1.07-1.24)]. CONCLUSIONS: An overwhelming majority of participants did not meet the standard-of-care for testing frequency. The reported motivations and barriers to testing highlight issues of risk perception and accessibility. Our findings suggest utilizing non-traditional outreach methods and promoting HIV testing as a routine part of healthcare in Peru to encourage testing and knowledge of HIV serostatus.

Characterizing the syphilis epidemic among men who have sex with men in Lima, Peru to identify new treatment and control strategies.

BACKGROUND: Syphilis is an important sexually transmitted infection (STI) with serious public health consequences. Among men who have sex with men (MSM) in Lima, the prevalence and incidence are extraordinarily high. Current syndromic approaches, however, fail to identify asymptomatic cases, and in settings where large proportions of individuals test positive again after treatment, it is frequently difficult to distinguish treatment failure from re-infection. Thus, new approaches are needed to improve treatment strategies and public health control efforts. METHODS/DESIGN: Study participants will undergo baseline testing for syphilis infection along with a behavioral survey covering demographics, sexual behavior, drug and alcohol abuse and health-care seeking behavior. The cohort will be followed for 18 months at three-month intervals. Blood and earlobe scrapings will also be collected for T. pallidum DNA testing, to create molecular markers for subtyping. We will also perform cytokine testing on collected samples in order to create host immunologic profiles associated with recurrence, re-infection, treatment failure and success. DISCUSSION: Advances in social epidemiology, molecular typing and characterization of host immune responses will offer promise in developing new understandings of syphilis management. We will share our findings with the Peruvian Ministry of Health and other public health organizations, to identify new approaches of case detection and successful treatment.

A Novel UHPLC-MS/MS Method for the Quantification of Seven Opioids in Different Human Tissues.

BACKGROUND: Opioids are considered the cornerstone of pain management: they show good efficacy as a first-line therapy for moderate to severe cancer pain. Since pharmacokinetic/pharmacodynamic information about the tissue-specific effect and toxicity of opioids is still scarce, their quantification in post-mortem autoptic specimens could give interesting insights. METHODS: We describe an ultra-high-performance liquid chromatography coupled with tandem mass spectrometry method for the simultaneous quantification of methadone, morphine, oxycodone, hydrocodone, oxymorphone, hydromorphone and fentanyl in several tissues: liver, brain, kidney, abdominal adipose tissue, lung and blood plasma. The presented method has been applied on 28 autoptic samples from different organs obtained from four deceased PLWH who used opioids for palliative care during terminal disease. RESULTS: Sample preparation was based on tissue weighing, disruption, sonication with drug extraction medium and a protein precipitation protocol. The extracts were then dried, reconstituted and injected onto the LX50 QSight 220 (Perkin Elmer, Milan, Italy) system. Separation was obtained by a 7 min gradient run at 40 °C with a Kinetex Biphenyl 2.6 µm, 2.1 × 100 mm. Concerning the analyzed samples, higher opioids concentrations were observed in tissues than in plasma. Particularly, O-MOR and O-COD showed higher concentrations in kidney and liver than other tissues (>15-20 times greater) and blood plasma (>100 times greater). CONCLUSIONS: Results in terms of linearity, accuracy, precision, recovery and matrix effect fitted the recommendations of FDA and EMA guidelines, and the sensitivity was high enough to allow successful application on human autoptic specimens from an ethically approved clinical study, confirming its eligibility for post-mortem pharmacological/toxicological studies.

Comparable Disease Severity by Influenza Virus Subtype in the Acute Respiratory Infection Consortium Natural History Study.

INTRODUCTION: Since the influenza A/H1N1 pandemic of 2009 to 2010, numerous studies have described the clinical course and outcome of the different subtypes of influenza (A/H1N1, A/H3N2, and B). A recent systematic literature review concluded that there were no appreciable differences in either clinical presentation or disease severity among these subtypes, but study parameters limit the applicability of these results to military populations. We sought to evaluate differences in disease severity among influenza subtypes in a cohort of healthy, primarily outpatient adult U.S. Department of Defense beneficiaries. MATERIALS AND METHODS: From 2009 to 2014, we enrolled otherwise healthy adults age 18 to 65 years with influenza-like illness in an observational cohort study based in 5 U.S. military medical centers. Serial nasopharyngeal swabs were collected for determination of etiology and viral shedding by polymerase chain reaction. The presence and severity of symptoms was assessed by interview and patient diary. RESULTS: Over a 5-year period, a total of 157 adults with laboratory-confirmed influenza and influenza subtype were enrolled. Of these, 69 (44%) were positive for influenza A(H1N1), 69 (44%) for influenza A(H3N2), and 19 (12%) for influenza B. About 61% were male, 64% were active duty military personnel, and 72% had received influenza vaccine in the past 8 months. Almost 10% were hospitalized with influenza. Seasonal influenza virus distribution among enrollees mirrored that of nationwide trends each year of study. Individuals with A/H1N1 had upper respiratory composite scores that were lower than those with A/H3N2. Multivariate models indicated that individuals with A(H1N1) and B had increased lower respiratory symptom scores when compared to influenza A(H3N2) (A[H1N1]: 1.51 [95% CI 0.47, 2.55]; B: 1.46 [95% CI 0.09, 2.83]), whereas no other differences in symptom severity scores among influenza A(H1N1), influenza A(H3N2), and influenza B infection were observed. Overall, influenza season (maximum in 2012-2013 season) and female sex of the participant were found to be associated with increased influenza symptom severity. CONCLUSIONS: Our study of influenza in a cohort of otherwise healthy, outpatient adult Department of Defense beneficiaries over 5 influenza seasons revealed few differences between influenza A(H1N1), influenza A(H3N2), and influenza B infection with respect to self-reported disease severity or clinical outcomes. This study highlights the importance of routine, active, and laboratory-based surveillance to monitor ongoing trends and severity of influenza in various populations to inform prevention measures.

Tuberculosis and illicit drug use: review and update.

Illicit drug users continue to be a group at high risk for tuberculosis (TB). Here, we present an updated review of the relationship between TB and illicit drug use, and we summarize more than a decade of new research. Drug users, and injection drug users in particular, have driven TB epidemics in a number of countries. The successful identification and treatment of TB among illicit drug users remain important components of a comprehensive TB strategy, but illicit drug users present a unique set of challenges for TB diagnosis and control. New diagnostic modalities, including interferon-gamma-release assays, offer potential for improved diagnosis and surveillance among this group, along with proven treatment strategies that incorporate the use of directly observed therapy with treatment for drug abuse. Special considerations, including coinfection with viral hepatitis and the rifampin-methadone drug interaction, warrant clinical attention and are also updated here.

A Comparison of Pretravel Health Care, Travel-Related Exposures, and Illnesses among Pediatric and Adult U.S. Military Beneficiaries.

We evaluated differences in pretravel care, exposures, and illnesses among pediatric and adult travelers, using a prospective, observational cohort. Eighty-one pediatric travelers were matched 1:1 with adult military dependents by travel region, destination's malaria risk, and travel duration. Pediatric travelers were more likely to have coverage for hepatitis A and B (90% versus 67% of adults; 85% versus 44%), visit friends and relatives (36% versus 16%), report mosquito bites (69% versus 44%), and have close contact with wild or domesticated animals (40% versus 20%) than adults (P < 0.05). Subjects < 10 years of age were less likely to be prescribed antibiotics (28% versus 95%; RR = 0.63; 95% CI: 0.46-0.85) and antidiarrheals (9% versus 100%; RR = 0.10; 95% CI: 0.03-0.29) for travelers' diarrhea (TD) self-treatment than adults. Travel medicine providers should emphasize strategies for vector avoidance, prevention of animal bites and scratches, and TD self-treatment in pediatric pretravel consultations.

Brief Report: Racial Comparison of D-Dimer Levels in US Male Military Personnel Before and After HIV Infection and Viral Suppression.

BACKGROUND: D-dimer blood levels in persons with HIV infection are associated with risk of serious non-AIDS conditions and death. Black race has been correlated with higher D-dimer levels in several studies. We examined the effects of race and HIV on D-dimer over time and the impact of viral load suppression by longitudinally comparing changes in levels among healthy young adult male African Americans and whites before HIV seroconversion and before and after initiation of antiretroviral therapy (ART). METHODS: We analyzed D-dimer levels and clinical and laboratory data of 192 participants enrolled in the US Military HIV Natural History Study, a 30-year cohort of military personnel infected with HIV. D-dimer levels were measured on stored sera from each participant at 3 time points: (1) before HIV seroconversion (Pre-SC), (2) ≥6 months after HIV seroconversion but before ART initiation (Post-SC), and (3) ≥6 months after ART with documented viral suppression (Post-ART). Levels were compared at each time point using nonparametric and logistic regression analysis. RESULTS: Compared with whites (n = 106), African Americans (n = 86) had higher D-dimer levels post-SC (P = 0.007), but in the same individuals, pre-SC baseline and post-ART levels were similar (P = 0.40 and P = 0.99, respectively). There were no racial differences in CD4 cell counts, HIV RNA viral load, time from estimated seroconversion to ART initiation, and duration on ART. CONCLUSIONS: Observed longitudinally, racial differences in D-dimer levels were seen only during HIV viremia. Higher levels of D-dimer commonly observed in African Americans are likely due to factors in addition to race.

Hospitalizations among HIV controllers and persons with medically controlled HIV in the U.S. Military HIV Natural History Study.

INTRODUCTION: HIV controllers (HICs) experience relatively low-level viraemia and CD4 preservation without antiretroviral therapy (ART), but also immune activation that may predispose to adverse clinical events such as cardiovascular disease and hospitalization. The objective of this study was to characterize the rates and reasons for hospitalization among HICs and persons with medically controlled HIV. METHODS: Subjects with consistently well-controlled HIV were identified in the U.S. Military HIV Natural History Study. ART prescription and HIV-1 RNA data were used to categorize subjects as HICs or medically controlled as defined by ≥ 3 HIV-1 RNA measurements ≤ 2000 or ≤ 400 copies/mL, respectively, representing the majority of measurements spanning ≥ 12 months. Hospitalizations were tallied and assigned diagnostic categories. All-cause hospitalization rates were compared between groups using negative binomial regression. RESULTS AND DISCUSSION: Of 3106 subjects followed from 2000 to 2013, 221 were HICs, including 33 elite (1.1%) and 188 viraemic (6.0%) controllers, who contributed 882 person-years (PY) of observation time. An additional 870 subjects with medically controlled HIV contributed 4217 PY. Mean hospitalization rates were 9.4/100 PY among HICs and 8.8/100 PY among medically controlled subjects. Non-AIDS-defining infections were the most common reason for hospitalization (2.95/100 PY and 2.70/100 PY, respectively) and rates of cardiovascular hospitalization were similar in both groups (0.45/100 PY and 0.76/100 PY). There was no difference in hospitalization rate for HICs compared with subjects with medically controlled HIV (adjusted incidence rate ratio 1.15 [95% confidence interval 0.80 to 1.65]). CONCLUSIONS: All-cause and cardiovascular hospitalization rates did not differ between HICs and persons with medically controlled HIV. Non-AIDS defining infections were common in this young, healthy, predominantly male cohort of military personnel and beneficiaries.

Prevalence of Staphylococcus aureus Colonization and Risk Factors for Infection Among Military Personnel in a Shipboard Setting.

Staphylococcal skin and soft tissue infections (SSTIs), especially those due to methicillin-resistant Staphylococcus aureus (MRSA) are an important public health issue for the military. Limited data exist regarding the prevalence of S. aureus colonization in the shipboard setting. We conducted a cross-sectional, observational study to determine the point prevalence of S. aureus colonization among military personnel onboard a naval vessel. Asymptomatic active duty personnel completed a survey for risk factors associated with colonization and SSTIs. Culture specimens were obtained from the anterior nares, pharynx, groin, and perirectal regions. MRSA isolates underwent testing for antimicrobial resistance, virulence factors, and pulsed-field type. 400 individuals were enrolled, 198 (49.5%) of whom were colonized with S. aureus, with MRSA identified in 14 participants (3.5%). No significant risk factors were associated with MRSA colonization. USA800 was the most common colonizing MRSA strain in the cohort and was detected in 10 participants (71%). Two participants (14%) were colonized with USA300 MRSA. In this first report of S. aureus epidemiology in a shipboard setting, we observed high rates of S. aureus and MRSA colonization. Longitudinal studies are needed to document the incident rates of S. aureus colonization during shipboard deployment and its impact on SSTI risk.

A comparison of compliance rates with anti-vectorial protective measures during travel to regions with dengue or chikungunya activity, and regions endemic for Plasmodium falciparum malaria.

BACKGROUND: There is limited information on compliance rates with anti-vectorial protective measures (AVPMs) during travel to countries with risk of dengue and chikungunya. We evaluated differences in mosquito exposures, and factors associated with AVPM compliance in travellers going to countries where the principal mosquito-borne infectious disease threat is falciparum malaria and those where risk of dengue or chikungunya predominates. METHODS: Department of Defence beneficiaries with planned travel to regions where the predominant mosquito-borne infection is falciparum malaria, and those with predominantly dengue or chikungunya risk, were included. Regions were divided into three groups: 'high-risk falciparum malaria', 'low-risk falciparum malaria' and 'chikungunya/dengue risk'. Demographics, trip characteristics, arthropod exposure and AVPM compliance were captured using pre- and post-travel surveys. Skin repellent compliance was defined as self-reported use, categorized as 'often/every day'. A logistic regression model was used to estimate factors associated with AVPM compliance. RESULTS: 183 (9%), 185 (9%) and 149 (7%) travelled to high and low falciparum malaria risk regions, and chikungunya/dengue risk regions, respectively. Overall, 53% (95% CI: 48-57%) and 16% (95% CI: 12-19%) were compliant with repellent use on skin and clothing, respectively. Daytime bites were reported more frequently in chikungunya/dengue risk regions than high malaria risk regions (37% vs. 10%), while night time bites were frequently in high malaria risk regions (53% vs 20%; P < 0.001). Compliance with skin repellents was associated with female gender [RR: 1.54 (95% CI: 1.05-2.28)], observing mosquitoes during travel [RR: 2.77 (95% CI: 1.76-4.36)] and travel during the rainy season [RR: 2.45 (95% CI: 1.66-3.71)]). CONCLUSIONS: Poor AVPM compliance was observed in the overall cohort. Compliance with skin repellent use was associated with female gender, observing mosquitoes and travelling during the rainy season, and was not associated with the risk of malaria or chikungunya/dengue at the travel destination.

Epidemiology and self-treatment of travelers' diarrhea in a large, prospective cohort of department of defense beneficiaries.

BACKGROUND: Infectious diarrhea is a common problem among travelers. Expert guidelines recommend the prompt use of antibiotics for self-treatment of moderate or severe travelers' diarrhea (TD). There is limited data on whether travelers follow these self-treatment guidelines. We evaluated the risk factors associated with TD, the use of TD self-treatment, and the risk of irritable bowel syndrome (IBS) during travel. METHODS: Department of Defense beneficiaries traveling outside the United States for ≤6.5 months were enrolled in a prospective cohort study. Participants received pre- and post-travel surveys, and could opt into a travel illness diary and follow-up surveys for symptoms of IBS. Standard definitions were used to assess for TD and IBS. Suboptimal self-treatment was defined as the use of antibiotics (with or without antidiarrheal agents) for mild TD, or the use of antidiarrheals alone or no self-treatment in cases of moderate or severe TD. RESULTS: Twenty-four percent of participants (270/1,120) met the criteria for TD. The highest incidence was recorded in Africa [8.6 cases/100 person-weeks, 95% confidence interval (CI): 6.7-10.5]. Two hundred and twelve participants with TD provided information regarding severity and self-treatment: 89 (42%) had mild TD and 123 (58%) had moderate or severe TD. Moderate or severe TD was independently associated with suboptimal self-treatment [OR 10.4 (95% CI: 4.92-22.0)]. Time to last unformed stool did not differ between optimal and suboptimal self-treatment. IBS occurred in 4.5% (7/154) of TD cases and in 3.1% (16/516) of cases without TD (p = 0.39). Among TD cases, a lower incidence of IBS was noted in participants who took antibiotics [4.8% (5/105) vs 2.2% (1/46)] in those who did not, but the difference did not reach statistical significance (p = 0.60). CONCLUSIONS: Our results suggest the underutilization of antibiotics in travelers with moderate or severe TD. Further studies are needed to systematically evaluate pre-travel instruction and traveler adherence to self-treatment guidelines, and the impact of suboptimal self-treatment on outcomes.

Vaccine-associated reduction in symptom severity among patients with influenza A/H3N2 disease.

BACKGROUND: The moderate level of protection conferred by influenza vaccines is well-known, but the vaccine's ability to attenuate symptom severity among vaccinated individuals (i.e., vaccine failures) has not been established. METHODS: We enrolled otherwise healthy adults who presented with influenza-like illness (ILI) at five US military hospitals between 2009 and 2014. Influenza was diagnosed and subtyped by PCR. Individual and composite severity scores were compared between those who had vs. had not received the seasonal influenza vaccine >14 days prior to enrollment. RESULTS: A total of 155 cases of influenza (A/H1N1, n=69; A/H3N2, n=66; A/untyped, n=3; B, n=17) were identified, of whom 111 (72%; A/H1N1, n=44; A/H3N2, n=52; A/untyped, n=3; B, n=12) had been vaccinated. Women were significantly less likely to be vaccinated than men (49% vs. 89%; p<0.01). In multivariate analysis, vaccinated individuals were significantly less likely to report a fever >101°F (OR 0.24; 95% CI [0.10, 0.62]) and more likely to report myalgias (OR 3.31; 95% CI [1.22, 8.97]) than vaccinated individuals. Among patients with A/H3N2 infection, upper respiratory and total symptom severity scores were significantly lower for vaccinated patients during the first 2 days of illness, and differences in total symptom severity persisted over 7 days (p<0.05 for all comparisons). Differences across additional symptom categories (lower respiratory and systemic) were also observed throughout 7 days of illness in bivariate analyses. Differences in symptom severity were not observed between vaccinated and unvaccinated participants with A/H1N1 infection. CONCLUSIONS: Among patients with A/H3N2 infection, receipt of seasonal influenza vaccine was associated with reduced symptom severity. Patient-centered discussion about the benefits of influenza vaccination should be expanded to include the possibility that the vaccine could attenuate symptoms.

Hepatitis B vaccine responsiveness and clinical outcomes in HIV controllers.

BACKGROUND: Hepatitis B virus (HBV) vaccine responsiveness is associated with reduced risk of AIDS or death in HIV-infected individuals. Although HIV controllers (HIC) typically have favorable immunologic and clinical characteristics compared to non-controllers, vaccine responsiveness has not been studied. METHODS AND FINDINGS: In the U.S. Military HIV Natural History Study, HBV vaccine response was defined as antibody to hepatitis B surface antigen (anti-HBs) ≥ 10 IU/L after last vaccination. For determination of vaccine responsiveness, HIC (n = 44) and treatment-naïve non-controllers (n = 476) were not on highly active antiretroviral therapy (HAART) when vaccinated while treated non-controllers (n = 284) received all HBV vaccine doses during viral load (VL)-suppressive HAART. Progression to AIDS or death was also compared for all HIC (n = 143) and non-controllers (n = 1566) with documented anti-HBs regardless of the timing of HBV vaccination. Positive vaccine responses were more common in HIC (65.9%) compared to HAART-naïve non-controllers (36.6%; P<0.001), but similar to non-controllers on HAART (59.9%; P = 0.549). Factors associated with vaccine response for HIC compared to HAART-naïve non-controllers include HIC status (OR 2.65, 95% CI 1.23-5.89; P = 0.014), CD4 count at last vaccination (OR 1.28, 1.15-1.45 for every 100 cells/uL; P<0.001), and number of vaccine doses administered (OR 0.56, 0.35-0.88; P = 0.011). When HIC were compared to non-controllers on HAART, only CD4 count at last vaccination was significant (OR 1.23, 1.1-1.38 for every 100 cells/uL; P<0.001). The rate of AIDS or death per 100 person/years for HIC compared to non-controllers was 0.14 (95% CI 0-0.76) versus 0.98 (95% CI 0.74-1.28) for vaccine responders and 0 (95% CI 0-2.22) versus 4.11 (95% CI 3.38-4.96) for non-responders, respectively. CONCLUSIONS: HIC have improved HBV vaccine responsiveness compared to treatment-naïve non-controllers, but similar to those on VL-suppressive HAART. Progression to AIDS or death can be predicted by HBV vaccine responder status for non-controllers, however these events are rarely observed in HIC.