[Occurrence of markers, distribution of genotypes and risk factors for viral hepatitis C among some groups of the population in the Novosibirsk region]. / Vstrechaemost' markerov, raspredelenie genotipov i faktory riska virusnogo gepatita C sredi naseleniia Novosibirskoi oblasti.

The occurrence of markers, genotypic variability of isolates and risk factors for viral hepatitis C (HCV) were studied in 4 groups of residents of the Novosibirsk region (altogether 2,000 persons). Anti-HCV IgG were detected within the range from 4.6% among medical personnel to 48% among the patients of the drug-abuse clinic. The detection rate of HCV RNA in seropositive samples varied from 79.3% to 86.3%. The determination of genotype was carried out for 388 isolates: 1b--50.3%, 2a--4.4%, 2c--0.3%, 3a--44.8%. The highest risk indices with respect to HCV among the residents of the region were linked with the drug use (OR=77.5; p<0.05) as well as with risky behavior and low social status. The elevated numbers of seropositive persons were detected among unemployed (OR=16.3), alcohol abusers (OR=3.9), persons having more than 4 sex partners in their lifetime (OR=4.3) and persons having homosexual contacts (OR=6.6). In some groups blood transfusions also played a definite role in the transmission of HCV. In the analysis, carried out separately for two different genotypes the intravenous use of drugs was perceptibly stronger linked with VHC of genotype 3 (OR=85.5) in comparison with HCV of genotype 1 (OR=49.3) and genotype 2 (OR=41.1). Genotype 1 prevailed in the older age group and genotype 3, among young people.

Biological weapons control. Prospects and implications for the future.

The Biological and Toxin Weapons Convention (BWC), which prohibits the acquisition of biological materials for hostile purposes and armed conflict, entered into force in 1975 and now has the participation of 140 nations (158 nations have signed the BWC, but only 140 of these have also ratified it). However, there is no monitoring mechanism associated with the BWC. Diplomatic efforts are now under way to create a supplemental, legally binding protocol to strengthen the convention. Measures to strengthen the BWC are analogous to the diagnostic processes familiar to physicians; the problem facing negotiators is to identify procedures with high positive and negative predictive value. Few proposed measures meet these criteria. However, the investigation of unusual disease outbreaks and allegations of use are highly diagnostic of illicit activities while avoiding false-positive accusations. At the same time, such information generated by the BWC can contribute to worldwide efforts to improve public health, control emergent disease, and establish an international norm against biological weapons proliferation.

Acquired methemoglobinemia and hemolytic anemia after usual doses of phenazopyridine.

Two patients developed symptomatic methemoglobinemia and hemolytic anemia after treatment with phenazopyridine. Methemoglobinemia appears to be a rare occurrence after commonly used doses of phenazopyridine; phenazopyridine-associated hemolytic anemia has been reported both after overdose and after usual doses. The presentation of methemoglobinemia in the first patient and the response to treatment with methylene blue in the second patient were unusual, suggesting that the patients had a red cell defect or were exposed to other oxidizing substances. One of the major metabolites of phenazopyridine is aniline, a known cause of methemoglobinemia. Aniline-induced methemoglobinemia is less responsive to treatment with methylene blue than nitrate- or nitrite-induced methemoglobinemia. This may explain, in part, the poor response to methylene blue by one of our patients.