Benin, West Africa. To describe the epidemiology of tuberculosis (TB) in Benin. Analysis of two tuberculin surveys initiated in 1987 and 1994 and of the quarterly reports of the Basic Management Units to the National Tuberculosis Programme from 1995 to 2007. The average annual risk for a child in Benin of becoming infected with Mycobacterium tuberculosis was around 0.5% in the mid 1980s. The notification rate increased by approximately 1% each year over the observation period and was on average 35 per 100,000 population, with a male-to-female sex ratio of 1.8 and no shift in the age structure of the cases over the observation period. Human immunodeficiency virus prevalence was 14% (97% of the patients were tested). There is a strong gradient of incident notification rates from the north to the south of the country that seems to be related to the population density. Both the tuberculin skin test survey results and the notification data suggest that the TB problem in Benin is much smaller than in eastern and southern African countries.

Despite several efforts aiming at disease control, the incidence of tuberculosis (TB) remains high in Greenland, averaging 131 per 100,000 population during the period 1998-2007. The purpose of the present study was to disclose risk factors for TB. A case-control study was performed among 146 patients diagnosed with TB in the period 2004-2006. For each patient, four healthy age- and sex-matched control persons living in the same district were included. All participants completed a questionnaire regarding socio-demographic and lifestyle factors. Risk factor analyses were carried out using logistic regression models. Factors associated with TB were Inuit ethnicity, living in a small settlement, unemployment, no access to tap water, no bathroom or flushing toilet, underweight, smoking, frequent intake of alcohol and immunosuppressive treatment. The multivariate model showed that Inuit ethnicity (OR 15.3), living in a settlement (OR 5.1), being unemployed (OR 4.1) and frequent alcohol use (OR 3.1) were independent determinants of risk. Unemployment was associated with the highest population-attributable risk (29%). Risk factors associated with living in a settlement should be further explored and an investigation of genetic susceptibility is warranted.

Screening with chest X-ray and the Mantoux test (the tuberculin skin test [TST]) is compulsory for adult asylum seekers who arrive in Norway. In 2005-2006, we included 823 asylum seekers in a study of the QuantiFERON-TB Gold test (QFT-G), and followed them for 23-32 months. Eight subjects with a positive and one with a negative QFT-G test were diagnosed with tuberculosis (TB). The positive (PPV) and negative predictive values (NPV) for TB were respectively 3.3% and 99.8%. The PPV was 2.3% and the NPV 99.1% for TST >or= 15 mm, and the NPV was 99.5% for TST >or= 6 mm in combination with a negative QFT-G.

The main tuberculosis (TB) centre in Benin, West Africa, where only 2% of adult pulmonary TB cases are sputum smear-negative, all other pulmonary cases being smear-positive. To assess the burden of smear-negative, culture-positive pulmonary TB among TB suspects in Cotonou, and to estimate the total number of non-smear-positive TB cases at country level. For 1 year, one morning sputum culture was performed for every TB suspect (cough lasting >3 weeks, as defined in Benin's national guidelines) with three negative sputum smears (fluorescence technique). Of 214 TB suspects for whom culture was performed, only 22 smear-negative, culture-positive cases were identified. During the same period, 831 sputum smear-positive cases were diagnosed. Culture therefore contributed only 2.6% of the total number of bacteriologically proven cases. These results show the relatively low input of culture in TB diagnosis among chronic coughers in Cotonou, Benin, and demonstrates that the expected number of non-smear-positive TB cases in Benin is probably much lower than the World Health Organization's current annual estimates.

Adult patients with tuberculosis (TB) recruited at the chest clinic of the University Teaching Hospital in Lusaka, Zambia, from 2003 to 2004. To identify factors associated with delayed treatment or hospitalisation. A cross-sectional survey of newly identified adult patients with TB. A total of 223 patients were included in the analysis. Patients with smear-negative disease were 2.6 times more likely to be hospitalised than those with smear-positive disease (95%CI 1.28-5.30), while patients with extra-pulmonary disease were 3.42 times more likely to be hospitalised than those with pulmonary disease (95%CI 1.75-6.66). Patients with smear-negative disease were 2.81 times more likely to have experienced overall delay than those with smear-positive disease (95%CI 1.20-6.66). This analysis has demonstrated that patients with extra-pulmonary or smear-negative disease are significantly more likely to be hospitalised. Patients with smear-negative disease are also more likely to have experienced treatment delay. These data reinforce the urgent need for more robust diagnostic tests, particularly for smear-negative and extra-pulmonary disease. As these forms of disease are more likely to be associated with the human immunodeficiency virus (HIV), the data support earlier diagnosis and treatment of HIV infection.

To study the association between TB and household expenditure in a nationwide TB prevalence survey in Viet Nam using nine household characteristics. To assess the prevalence of TB in Viet Nam, a nationwide stratified cluster sample survey was conducted from 2006 to 2007. Nine household characteristics used in the second Viet Nam Living Standards Survey (VLSS) were scored per household. In the VLSS dataset, we regressed these nine characteristics against household expenditure per capita, and used the coefficients to predict household expenditure level (in quintiles) in our survey and assess its relation with TB prevalence. The prevalence of bacteriologically confirmed TB was 307 per 100,000 population in persons aged ≥ 15 years (95%CI 249-366). After adjustment for confounders, prevalence was found to be associated with household expenditure level: the rate was 2.5 times higher for those in the lowest household expenditure quintile (95%CI 1.6-3.9) than those in the highest quintile. With a set of nine household characteristics, we were able to predict household expenditure level fairly accurately. There was a significant association between TB prevalence rates and estimated household expenditure level, showing that TB is related to poverty in Viet Nam.

Empiric use of fluoroquinolone (FQ) antibiotics could delay tuberculosis (TB) treatment and lead to FQ-resistant TB. We examined the impact of FQ use on TB outcomes, including smear status, treatment delay and FQ resistance, through a retrospective cohort study of 440 FQ-exposed and 511 non-exposed patients in a gold mining community in South Africa. We considered both recent (≤ 100 days before sputum collection) and distant exposure (≤ 1 year). We examined 201 and 180 isolates from FQ-exposed and non-exposed individuals for the presence of gyrA mutations. Patients recently exposed to ≥ 5 days of FQ were less likely to be smear-positive (OR 0.27, 95%CI 0.11-0.63), with an increased time to treatment (time ratio 2.02, 95%CI 1.19-3.44). The strength of association decreased when we considered distant exposure. Adjusting for smear status nullified the effect of FQ exposure on treatment delay. We detected a gyrA mutation in one isolate (0.5%) taken from an individual exposed to FQ for 8 days. FQ exposure is associated with treatment delay, mediated by negative smear status. Short exposures to FQ do not routinely lead to resistance encoded by gyrA mutations. We recommend prudent use of FQ in settings with a high burden of human immunodeficiency virus and TB.

Two thirds of tuberculosis (TB) patients in the Netherlands are foreign-born. To determine if travelling to the country of origin is a risk factor for TB among two different immigrant groups that have lived in the Netherlands for at least 2 years. In this unmatched case-control study, the frequency and duration of travel to the country of origin in the preceding 12 months were compared between adult Moroccan and Turkish TB patients and community controls. Moroccan patients had travelled more often (26/32 = 81%) in the preceding year than Moroccan controls (472/816 = 58%). The travel-associated odds ratio (OR) for TB among Moroccans was 3.2 (95%CI 1.3-7.7), and increased to 17.2 (95%CI 3.7-79) when the cumulative duration of travel exceeded 3 months. The corresponding population fraction of Moroccan TB cases attributable to recent travel was 56% (95%CI 19-71). Among Turkish immigrants TB was not associated with travel (OR 0.9, 95%CI 0.3-2.4). Travel to the country of origin was a risk factor for TB among Moroccans, but not among Turkish people living in the Netherlands. The difference in travel-associated OR between these two immigrant groups is probably related to differences in TB incidence in these countries.

This Supplement provides an update on guidelines first published in 1996 on conducting a tuberculin skin test survey and analyzing the resulting data. The updated guidelines add experiences gained from community surveys, revisit the proposed sampling strategies, and provide additional information on ethical considerations.