Avian influenza A (H5N1) in 10 patients in Vietnam.

BACKGROUND: Recent outbreaks of avian influenza A (H5N1) in poultry throughout Asia have had major economic and health repercussions. Human infections with this virus were identified in Vietnam in January 2004. METHODS: We report the clinical features and preliminary epidemiologic findings among 10 patients with confirmed cases of avian influenza A (H5N1) who presented to hospitals in Ho Chi Minh City and Hanoi, Vietnam, in December 2003 and January 2004. RESULTS: In all 10 cases, the diagnosis of influenza A (H5N1) was confirmed by means of viral culture or reverse transcriptase-polymerase chain reaction with primers specific for H5 and N1. None of the 10 patients (mean age, 13.7 years) had preexisting medical conditions. Nine of them had a clear history of direct contact with poultry (median time before onset of illness, three days). All patients presented with fever (temperature, 38.5 to 40.0 degrees C), respiratory symptoms, and clinically significant lymphopenia (median lymphocyte count, 700 per cubic millimeter). The median platelet count was 75,500 per cubic millimeter. Seven patients had diarrhea. In all patients, there were marked abnormalities on chest radiography. There was no definitive evidence of human-to-human transmission. Eight patients died, one patient has recovered, and one is recovering. CONCLUSIONS: Influenza A (H5N1) infection, characterized by fever, respiratory symptoms, and lymphopenia, carries a high risk of death. Although in all 10 cases the infection appears to have been acquired directly from infected poultry, the potential exists for genetic reassortment with human influenzaviruses and the evolution of human-to-human transmission. Containment of influenza A (H5N1) in poultry throughout Asia is therefore urgently required.

Hepatitis B infection in rural Vietnam and the implications for a national program of infant immunization.

To ascertain hepatitis B virus (HBV) infection rates for Vietnam, we surveyed HBV markers in two districts of Thanh Hoa province. We randomly selected 536 infants (9- < or = 18 months old), 228 children (4 to < or = 6 years old), 219 adolescents (14 to < or = 16 years old), and 596 adults (25 to < or = 40 years old). On questioning, none of those surveyed had received vaccine against HBV. Hepatitis B virus surface antigen (HBsAg) and total HBV core antibody (anti-HBc) were measured in all specimens, and HBV e antigen (HBeAg) in those positive for HBsAg, and HBV surface antibody (anti-HBs) were measured in all others. Current infection (HBsAg+) rates were infants = 12.5%, children = 18.4%, adolescents = 20.5%, and adults = 18.8%. Current or previous infection (HBsAg+, anti-HBc+, or anti-HBs+) increased with age (infants = 19.6%, children = 36.4%, adolescents = 55.3%, adults = 79.2%). Rates of HBeAg among those HBsAg+ were infants = 85.1%, children = 88.1%, adolescents = 71.1%, and adults = 30.4%. The epidemiology of HBV in Vietnam resembles that of many southeast Asian nations before introduction of vaccine. Immunization of newborns will have enormous impact on HBV-related morbidity and mortality there.

Intravenous drug use among street-based sex workers: a high-risk behavior for HIV transmission.

BACKGROUND: HIV prevalence among sex workers in Ho Chi Minh City has increased rapidly, from 6.5% in 1999 to 18.1% in 2000. This study examined whether injecting drug use among street-based sex workers (SSWs) in Ho Chi Minh City is a high-risk factor for HIV infection. GOAL: The goal of this study was to determine the correlates and prevalence of intravenous drug users among SSWs in Ho Chi Minh City. STUDY DESIGN: A cross-sectional study was conducted among SSWs in Ho Chi Minh City during December 2000. The SSWs were interviewed and tested for HIV-1. RESULTS: HIV-1 seroprevalence was 16.3%. Regression analysis indicated that injecting drugs and being younger than 25 years of age were independently associated with HIV seropositivity. CONCLUSION: Young SSWs who inject drugs are at the greatest risk of contracting HIV and acting as a bridge for HIV to the sexually active population.

Endemic, epidemic clone of Salmonella enterica serovar typhi harboring a single multidrug-resistant plasmid in Vietnam between 1995 and 2002.

Salmonella enterica serovar Typhi strains resistant to ampicillin, chloramphenicol, tetracyclines, streptomycin, and cotrimoxazole, isolated from sporadic cases and minor outbreaks in Vietnam between 1995 and 2002, were typed and compared. Plasmid fingerprinting, Vi bacteriophage typing, XbaI pulsed-field gel electrophoresis, and PstI ribotyping showed that endemic, epidemic multidrug-resistant typhoid fever was due, for at least 74.1% of the isolates, to one or two clones of serovar Typhi harboring a single resistance plasmid. PstI ribotyping was used as a basic technique to ensure that a serovar Typhi expansion was clonal.