BACKGROUND: WHO recommends screening for TB and evaluation for isoniazid preventive therapy (IPT) based on evidence that they reduce TB-related morbidity and mortality among HIV-infected persons. In Vietnam, an IPT pilot was implemented in two provinces; TB screening, treatment and outcomes were evaluated to inform the adoption and scale-up of IPT. METHODS: During April 2008 to March 2010, eligible HIV-infected persons aged >15 years, with no previous or current TB treatment, alcohol abuse or liver disease were screened for TB. If TB disease was ruled out based on symptoms, chest x-rays and sputum smears, isoniazid was administered for 9 months. RESULTS: Among 1281 HIV-infected persons who received initial eligibility screening, 520 were referred to and evaluated at district TB clinics for TB disease or IPT eligibility. Active TB was diagnosed in 17 patients and all were started on treatment. Of 520 patients evaluated, 416 (80.0%) initiated IPT: 382 (91.8%) completed IPT, 17 (4.1%) stopped treatment, 8 (1.9%) died, 3 (0.7%) developed TB during IPT and 6 (1.4%) had unknown outcomes. No severe adverse events were reported. CONCLUSIONS: IPT treatment completion was high; no serious complications occurred. Improving and expanding intensified case-finding and IPT should be considered in Vietnam.

OBJECTIVE: Use of tuberculin skin tests (TSTs) and interferon gamma release assays (IGRAs) as part of tuberculosis (TB) screening among immigrants from high TB-burden countries has not been fully evaluated. METHODS: Prevalence of Mycobacterium tuberculosis infection (MTBI) based on TST, or the QuantiFERON-TB Gold test (QFT-G), was determined among immigrant applicants in Vietnam bound for the United States (US); factors associated with test results and discordance were assessed; predictive values of TST and QFT-G for identifying chest radiographs (CXRs) consistent with TB were calculated. RESULTS: Of 1,246 immigrant visa applicants studied, 57.9% were TST positive, 28.3% were QFT-G positive, and test agreement was 59.4%. Increasing age was associated with positive TST results, positive QFT-G results, TST-positive but QFT-G-negative discordance, and abnormal CXRs consistent with TB. Positive predictive values of TST and QFT-G for an abnormal CXR were 25.9% and 25.6%, respectively. CONCLUSION: The estimated prevalence of MTBI among US-bound visa applicants in Vietnam based on TST was twice that based on QFT-G, and 14 times higher than a TST-based estimate of MTBI prevalence reported for the general US population in 2000. QFT-G was not better than TST at predicting abnormal CXRs consistent with TB.

RATIONALE: Each year 1 million persons acquire permanent U.S. residency visas after tuberculosis (TB) screening. Most applicants undergo a 2-stage screening with tuberculin skin test (TST) followed by CXR only if TST-positive at > 5 mm. Due to cross reaction with bacillus Calmette-Guerin (BCG), TST may yield false positive results in BCG-vaccinated persons. Interferon gamma release assays exclude antigens found in BCG. In Vietnam, like most high TB-prevalence countries, there is universal BCG vaccination at birth. OBJECTIVES: 1. Compare the sensitivity of QuantiFERON (R)-TB Gold In-Tube Assay (QFT) and TST for culture-positive pulmonary TB. 2. Compare the age-specific and overall prevalence of positive TST and QFT among applicants with normal and abnormal CXR. METHODS: We obtained TST and QFT results on 996 applicants with abnormal CXR, of whom 132 had TB, and 479 with normal CXR. RESULTS: The sensitivity for tuberculosis was 86.4% for QFT; 89.4%, 81.1%, and 52.3% for TST at 5, 10, and 15 mm. The estimated prevalence of positive results at age 15-19 years was 22% and 42% for QFT and TST at 10 mm, respectively. The prevalence increased thereafter by 0.7% year of age for TST and 2.1% for QFT, the latter being more consistent with the increase in TB among applicants. CONCLUSIONS: During 2-stage screening, QFT is as sensitive as TST in detecting TB with fewer requiring CXR and being diagnosed with LTBI. These data support the use of QFT over TST in this population.

BACKGROUND: An estimated 120,000 HIV-associated cryptococcal meningitis (CM) cases occur each year in South and Southeast Asia; early treatment may improve outcomes. The World Health Organization (WHO) recently recommended screening HIV-infected adults with CD4<100 cells/mm(3) for serum cryptococcal antigen (CrAg), a marker of early cryptococcal infection, in areas of high CrAg prevalence. We evaluated CrAg prevalence and cost-effectiveness of this screening strategy in HIV-infected adults in northern and southern Vietnam. METHODS: Serum samples were collected and stored during 2009-2012 in Hanoi and Ho Chi Minh City, Vietnam, from HIV-infected, ART-naive patients presenting to care in 12 clinics. All specimens from patients with CD4<100 cells/mm(3) were tested using the CrAg lateral flow assay. We obtained cost estimates from laboratory staff, clinicians and hospital administrators in Vietnam, and evaluated cost-effectiveness using WHO guidelines. RESULTS: Sera from 226 patients [104 (46%) from North Vietnam and 122 (54%) from the South] with CD4<100 cells/mm(3) were available for CrAg testing. Median CD4 count was 40 (range 0-99) cells/mm(3). Nine (4%; 95% CI 2-7%) specimens were CrAg-positive. CrAg prevalence was higher in South Vietnam (6%; 95% CI 3-11%) than in North Vietnam (2%; 95% CI 0-6%) (p = 0.18). Cost per life-year gained under a screening scenario was $190, $137, and $119 at CrAg prevalences of 2%, 4% and 6%, respectively. CONCLUSION: CrAg prevalence was higher in southern compared with northern Vietnam; however, CrAg screening would be considered cost-effective by WHO criteria in both regions. Public health officials in Vietnam should consider adding cryptococcal screening to existing national guidelines for HIV/AIDS care.

Noroviruses (NoV) and sapoviruses (SaV) are recognized as important causes of acute gastroenteritis in children worldwide. In this study, the prevalence and genetic variability of NoV and SaV were determined in hospitalized children <5 years of age with acute gastroenteritis in Hanoi, Vietnam. A total of 501 fecal specimens collected between November-2007 and October-2008, that previously had been tested for rotavirus (RV), were tested for NoV and SaV by realtime RT-PCR. Positive samples were genotyped by conventional RT-PCR followed by sequencing. GII NoV was detected in 180 (36%) and SaV in 7 (1.4%) of the samples. NoV was detected year-round ranging from 9.5% in April to 81.5% in September among RV negative samples. NoV GII.4 Minerva (2006b) was the dominant genotype (93%) with a few other genotypes detected including GII.3 (4.4%), GII.13 (1.7%), and GII.2 (0.6%) but no GI strains. Only GI and GII SaV strains were detected in this study. No difference in NoV prevalence between age groups was noted. Frequency of vomiting or fever was similar between children with NoV and RV infection, yet, NoV caused diarrhea with longer duration. In conclusion, NoV is the second most frequent cause of diarrhea in hospitalized children in North Vietnam. (J. Med. Virol. 84:290-297, 2012. (c) 2011 Wiley Periodicals, Inc.)