Association between household solid fuel use and tuberculosis: cross-sectional data from the Mongolian National Tuberculosis Prevalence Survey

BACKGROUND@#Tuberculosis (TB) and indoor air pollution (IAP) are equally critical public health issues in the developing world. Mongolia is experiencing the double burden of TB and IAP due to solid fuel combustion. However, no study has assessed the relationship between household solid fuel use and TB in Mongolia. The present study aimed to assess the association between household solid fuel use and TB based on data from the Mongolian National Tuberculosis Prevalence Survey (MNTP Survey).@*METHOD@#The MNTP Survey was a nationally representative population-based cross-sectional survey targeting households in Mongolia from 2014 to 2015, with the aim of evaluating the prevalence of TB. The survey adopted a multistage cluster sampling design in accordance with the World Health Organization prevalence survey guidelines. Clusters with at least 500 residents were selected by random sampling. A sample size of 98 clusters with 54,100 participants was estimated to be required for the survey, and 41,450 participants were included in the final analysis of the present study. A structured questionnaire was used to collect information on environmental and individual factors related to TB. Physical examination, chest X-ray, and sputum examinations were also performed to diagnose TB.@*RESULTS@#The use of solid fuels for heating (adjusted odds ratio (aOR): 1.5; 95% confidence interval (CI): 1.1-2.1), male gender (aOR: 2.2; 95% CI: 1.6-3.2), divorced or widowed (aOR: 2.6; 95% CI: 1.7-3.8), daily smoker (aOR: 1.8; 95% CI: 1.3-2.5), contact with an active TB case (aOR: 1.7; 95% CI: 1.2-2.3), being underweight (aOR: 3.7; 95% CI: 2.4-5.7), and previous history of TB (aOR: 4.3; 95% CI: 3.0-6.1) were significantly associated with bacteriologically confirmed TB after adjusting for confounding variables.@*CONCLUSION@#The use of solid fuels for heating was significantly associated with active TB in Mongolian adults. Increased public awareness is needed on the use of household solid fuels, a source of IAP.

Recent Situation of Taeniasis in Mongolia (2002-2012)

Epidemiological situation of taeniasis in Mongolia was assessed based on mitochondrial DNA identification of the parasite species. Multiplex PCR was used on a total of 194 proglottid specimens of Taenia species and copro-PCR and loop-mediated isothermal amplification (LAMP) assays were utilized for detection of copro-DNA of 37 fecal samples from taeniasis patients submitted to the Mongolian National Center for Communicable Diseases (NCCD) from 2002 to 2012. In addition, 4 out of 44 calcified cysts in beef kept in formalin since 2003 were evaluated for histopathological confirmation of cattle cysticercosis. All proglottid specimens and stool samples were confirmed to be Taenia saginata by multiplex PCR and by copro-PCR and LAMP, respectively. Cysts collected from cattle were morphologically confirmed to be metacestodes of Taenia species. T. saginata taeniasis was identified from almost all ages from a 2-year-old boy up to a 88-year-old woman and most prominently in 15-29 age group (37%, 74/198) followed by 30-44 age group (34.8%, 69/198 ) from 15 of Mongolia's 21 provinces, while cattle cysticerci were found from 12 provinces. The highest proportion of taeniasis patients was in Ulaanbaatar, the capital of Mongolia.

Molecular Detection and Seroprevalence of Babesia microti among Stock Farmers in Khutul City, Selenge Province, Mongolia

Babesiosis is an emerging tick-borne disease in humans worldwide; however, little is known about the frequency of infection or prevalence of this disease in other parts of the world, excluding North America. In this study, we aimed to investigate Babesia microti infection frequency in a human population in Mongolia. One hundred blood samples were collected from stock farmers living in Khutul city of Selenge province, Mongolia. The sera and DNA from blood samples were evaluated for the presence of B. microti infection by using indirect fluorescent antibody (IFA) tests and PCR. The positive detection rates obtained using the IFA tests and PCR assays were 7% and 3%, respectively. This study is the first to detect of B. microti infections based on antibody seroprevalence or PCR assays for the presence of B. microti DNA in a Mongolian population.

Status Quo of Chronic Liver Diseases, Including Hepatocellular Carcinoma, in Mongolia

Because Mongolia has much higher liver disease burden than any other regions of the world, it is necessary to provide information on real-time situation of chronic liver disease in Mongolia. In this article, we reviewed studies performed in Mongolia from 2000 to 2011 on seroprevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) among healthy individuals and patients with chronic liver diseases, and on the practice patterns for the management of liver cirrhosis and hepatocellular carcinoma (HCC). According to previous reports, the seroprevalence of HBV and HCV in general population in Mongolia is very high (11.8% and 15% for HBV and HCV, respectively). Liver cirrhosis is also highly prevalent, and mortality from liver cirrhosis remained high for the past decade (about 30 deaths per 100,000 populations per year). Among patients with cirrhosis, 40% and 39% are positive for HBsAg and anti-HCV, respectively, and 20% are positive for both. The seroprevalence is similar for HCC and more than 90% of HCC patients are positive for either HBV or HCV. The incidence of HCC in Mongolia is currently among the highest in the world. The mortality from HCC is also very high (52.2 deaths per 100,000 persons per year in 2010). Partly due to the lack of established surveillance systems, most cases of HCC are diagnosed at an advanced stage. The mortality from liver cirrhosis and HCC in Mongolia may be reduced by implementation of antiviral therapy program and control of alcohol consumption.

Analysis of genetic and non-genetic factors that affect the QTc interval in a Mongolian population: the GENDISCAN study

The QTc interval is a complex quantitative trait and a strong prognostic indicator of cardiovascular mortality in general, healthy people. The aim of this study was to identify non-genetic factors and quantitative trait loci that govern the QTc interval in an isolated Mongolian population. We used multiple regression analysis to determine the relationship between the QTc interval and non-genetic factors including height, blood pressure, and the plasma lipid level. Whole genome linkage analyses were performed to reveal quantitative trait loci for the QTc interval with 349 microsatellite markers from 1,080 Mongolian subjects. Among many factors previously known for association with the QTc interval, age, sex, heart rate, QRS duration of electrocardiogram and systolic blood pressure were also found to have influence on the QTc interval. A genetic effect for the QTc interval was identified based on familial correlation with a heritability value of 0.31. In a whole genome linkage analysis, we identified the four potential linkage regions 7q31-34, 5q21, 4q28, and 2q36.

Prevalence and correlates of environmental tobacco smoke exposure among adolescents in Mongolia.

OBJECTIVE: To estimate the prevalence and identify correlates of environmental tobacco exposure (ETS) among adolescents in Mongolia. METHODS: A cross-sectional study was carried out in 2003 in Mongolia within the framework of the Global Youth Tobacco Survey. Information was obtained on exposure to Environmental tobacco smoke (ETS) in the home and outside home, parental and peer smoking. Demographic characteristics such as age and sex were also obtained. Data were analyzed to obtain frequencies of characteristics. Logistic regression analysis was conducted to assess the association between ETS and relevant predictor variables. RESULTS: 73.9% (71.6%-76.1%) males and 71.7% (69.7%-73.7%) females reported being exposed to ETS either in the home or elsewhere. The odds of exposure were 5.85 (3.83-8.92) if both parents were smokers, 3.65(3.10-4.30) if only father smoked and 6.54 (3.48-12.32) if only mother smoked. Older adolescents were more likely to be exposed to ETS than younger adolescents. Prevalence of exposure to ETS within the home was similar between males and females but males had a higher prevalence of exposure outside of the home than females (50.7% and 42.4% respectively (p < 0.001). Overall proportion of adolescents exposed to ETS in the home was higher than those exposed outside suggesting that domestic exposure was the main form of ETS among adolescents in Mongolia. CONCLUSION: Exposure to environmental tobacco smoke is high among school going adolescents in Mongolia. Public health interventions aimed to reduce morbidity from tobacco among adolescents should also accord particular attention toward environmental tobacco smoke.

Antenatal care providers' practices and opinions on the services of antenatal syphilis screening in Ulaanbaatar, Mongolia.

The objectives of this study were to review antenatal syphilis screening and to assess antenatal care providers' practices and opinions in Ulaanbaatar, Mongolia. A cross-sectional study on antenatal syphilis screening was conducted. The study settings were all 16 antenatal care clinics, and a random selection of 30 family units from six districts in Ulaanbaatar, Mongolia. Interviews were conducted with 150 antenatal care providers and 27 antenatal care heads/leaders. Antenatal syphilis screening in Ulaanbaatar was complex. Most pregnant women had antenatal care at family units or antenatal clinics, but syphilis blood testing could be performed only in some district general hospitals. Syphilis positive-screening cases were referred to the venereologists for confirmation of results, appropriate treatment, contact tracing, and follow-up. The providers agreed with the need for syphilis screening in pregnant women but identified as constraints the limited time for performing the screening due to late antenatal visit, women's lack of knowledge, poverty, and geographic barriers. The practice of providers varied, and the opinion on a one-stop service was positive. The main conclusions concerning the failure of universal antenatal syphilis screening were limited accessibility and feasibility of the service, and the ignorance of both women and providers on the importance of screening. It was agreed that decentralization of antenatal syphilis screening would improve the system.

Smoking cessation rate 12 months after a group counseling program in Mongolia.

Mongolia is one of the top ten countries with the highest smoking rates of men and women combined, so that tobacco control, especially creating effective smoking cessation programs, is essential issue of the government. The present study aimed to assess an effectiveness of a free group counseling program by trained medical doctors and health educators based on "5A" (Ask, Assess, Advise, Assist, and Arrange) with 12 months follow-up in 2002 and 2003. Participants were 517 smokers with an intention to quit smoking in three big cities (Ulaanbaatar, Darkhan, and Erdenet). We found that 65.0% of them were not smokers 12 months after the program. The cessation rate was significantly higher in 2003 than in 2002, indicating that the effectiveness of the program had improved over time. Group counseling based on the "5A" approach by medical doctors and health educators seems effective for smokers with an intention to quit smoking. The present approach may be more appropriate in Mongolian conditions than nicotine replacement therapy.

Hepatocellular carcinoma and its early detection by AFP testing in Mongolia.

Liver cancer is one of the leading causes of cancer death in Mongolia. Since 1982-1986 , when HCC became the most frequent cancer among the Mongolian population, the rate has been increasing continuously. In the period 2000-2005 years 35.3%of all newly registered cancer cases were liver cancers, with an incidence rate of 51.3 per 100,000 population. Compared to the previous 5 year period, the rate increased by 11%. The objective here was to analyze hepatitis B (HBV) and C virus (HCV)-related HCC cases and to evaluate the possibility of tumor marker (AFP) testing for early detection in Mongolia. Sera from a total of 513 patients with chronic liver diseases, liver cirrhosis and HCC were analyzed for liver function (ALAT, ASAT) and hepatitis virus markers (HBsAg, anti-HCV). Sera from 316 patients were also examined for alpha-fetoprotein (AFP) levels. The overall incidence of HBsAg or anti-HCV were very high ( 95.3%) among all patients. Some 33.5% (66/197) of patients with HCC were positive for HBsAg and 45.2% (89/197) for anti-HCV. Moreover, 17.3% ( 34/197) of HCC patients demonstrated co-infection with HBV and HCV. AFP levels were elevated in 4.6% (11/238) and 29.5% (23/78) of chronic hepatitis and cirrhosis patients, respectively. In HCC cases, 84.3% (166) of patients had increased level of AFP ranging from 32 ng/ml to more than 400 ng/ml. We conclude that HBV/HCV infection is the main factor related to development of HCC in Mongolia and that testing for AFP serum levels is a useful tool for early detection and diagnosis.

Intestinal protozoan infections and echinococcosis in the inhabitants of Dornod and Selenge, Mongolia(2003)

The status of intestinal parasitic infections and seroprevalence of cystic echinococcosis in the inhabitants in Dornod and Selenge, Mongolia, was observed with stool and serum samples from 165 and 683 residents from August 9 to August 15, 2003. A total of 10 inhabitants (6.1%) were found to be infected with protozoan cysts or oocysts by stool examinations; 7, 1 and 2 cases with Entamoeba coli, Giardia lamblia and Cryptosporidium parvum, respectively. A total of 62 people (9.1%) revealed significantly high levels of specific antibodies against Echinococcus granulosus by enzyme-linked immunosorbent assay (ELISA). The surveyed areas are rural areas and the sanitized tab water is not available. There is a possibility of endemic transmission of water-borne protozoan diseases in these areas. The clinical echinococcosis is needed to be searched from the seropositive inhabitants.

National neonatal hypothyroid screening program in Mongolia.

This study was motivated by the desire to identify patients with congenital hypothyroidism for early treatment. A pilot project was developed by the Department of Nuclear Medicine and initial screening was began at 2 of the maternity houses in Ulaanbaatar. The methodology used for these activities involved collecting samples by heel prick at 3-4 days of age and analysed for TSH by immunoradiometric testing (Skybio Ltd, United Kingdom). From July 2000 to September 2001, 1,529 babies were screened. Although there were no positive screens from neonatal screening, TSH was high and T4 was low in 2 cases referred by the endocrinologist and therefore leading to treatment. The programme appears to be of important significance to the country and thus committed to further improving the implementation of the program.

Prevalence of Sarcocystis infection in horses in Mongolia.

Sarcocystis infection was detected in 93% of horses in Mongolia. Using the compress method, sarcocysts were found in the muscles of the diaphragm, heart and tongue in 40 of the 43 horses that were slaughtered at the Makh Impex Meat Company in Ulaan Baatar in July 1998. The muscle of the tongue showed the highest rate (97.5%) of infection. The distribution of sarcocysts in the muscles was positively correlated with horse age; the rate of detection was significantly lower (p=0.01) in the under 10 year old group than the older group. All horses were apparently healthy and were slaughtered for human consumption.

Prevalence of Sarcocystis infection in meat-producing animals in Mongolia.

A survey of Sarcocystis infection was conducted in Mongolia between June 1998 and July 1999. Samples of muscle were taken from the diaphragm, heart, tongue, esophagus,and intercostal region of cattle, yak, hainag, sheep, horses, and camels. A muscle compress method was used to determine the prevalence of infection: cattle 90.0% (27/30), yak 93.3% (28/30), hainag 100% (30/30), sheep 96.9% (753/777), horses 75% (3/4) and camels 100% (5/5). Of the various muscles, heart was the most commonly infected in cattle (100%), yak (86.7%), and hainag (100%); tongue was most likly to be infected in sheep (100%) and horses (100%).