Risk factors for tuberculosis in older children and adolescents: a matched case–control study in Recife,Brazil

Background

Tuberculosis is a major disease worldwide and most research focus on risk factors for adults, although there is a marked adolescent peak in incidence. The objective of this study was to identify risk factors for tuberculosis in children aged 7 to 19.

Methods

A case control study matched by age with 169 cases and 477 controls. The study population consisted of adolescents and older children from Recife, Brazil. Cases were individuals diagnosed with tuberculosis in the control programme and controls were selected in the neighborhood of cases. Conditional logistic regression was used to identify risk factors.

Results

Cigarette smoking increased by 50% the risk of tuberculosis but that this was not statistically significant (OR?=?1.6). Other risk factors were sleeping in the same house as a case of tuberculosis (OR?=?31.6), living in a house with no piped water (OR?=?7.7) (probably as a proxy for bad living conditions), illiteracy (OR?=?3.7) and male sex (OR?=?1.8). The increase in risk with living in houses with no piped water was much more marked in males. The proportion of cases of tuberculosis attributed to contact with someone with TB was 38% and to illiteracy, lack of piped water and smoking, 20%.

Conclusion

Household contact with tuberculosis, social factors and male sex play the biggest role in determining risk of TB disease among children and adolescents in the study. We recommend further research on the relationship of cigarette smoking on tuberculosis in adolescents, and on whether the sex differentials are more marked in bad living conditions. Separate studies should be conducted in older children and in adolescents.

     

Risk factors for tuberculosis among health care workers in South India: a nested case–control study

ObjectiveThe epidemiology of tuberculosis (TB) among health care workers (HCWs) in India remains under-researched. This study is a nested case–control design assessing the risk factors for acquiring TB among HCWs in India.Study Design and SettingsIt is a nested case–control study conducted at a tertiary teaching hospital in India. Cases (n = 101) were HCWs with active TB. Controls (n = 101) were HCWs who did not have TB, randomly selected from the 6,003 subjects employed at the facility. Cases and controls were compared with respect to clinical and demographic variables.ResultsThe cases and controls were of similar age. Logistic regression analysis showed that body mass index (BMI) <19 kg/m² (odds ratio [OR]: 2.96, 95% confidence interval [CI]: 1.49–5.87), having frequent contact with patients (OR: 2.83, 95% CI: 1.47–5.45) and being employed in medical wards (OR: 12.37, 95% CI: 1.38–110.17) or microbiology laboratories (OR: 5.65, 95% CI: 1.74–18.36) were independently associated with increased risk of acquiring TB.ConclusionHCWs with frequent patient contact and those with BMI <19 kg/m² were at high risk of acquiring active TB. Nosocomial transmission of TB was pronounced in locations, such as medical wards and microbiology laboratories. Surveillance of high-risk HCWs and appropriate infrastructure modifications may be important to prevent interpersonal TB transmission in health care facilities.     

‘In different situations,in different ways’: male sex work in St. Petersburg,Russia

We conducted a qualitative study of male sex work in St. Petersburg Russia with a focus on social vulnerabilities, HIV-risk perception and HIV-related behaviours. In-depth interviews were conducted with individuals knowledgeable about male sex work through their profession and with male sex workers themselves. Male sex work involves a variety of exchanges, including expensive vacations, negotiated monetary amounts or simply access to food. Methods of finding clients included the Internet, social venues (e.g. gay clubs and bars) and public places (e.g. parks). Use of the Internet greatly facilitated male sex work in a variety of ways. It was used by both individuals and agencies to find clients, and appeared to be increasing. Men often reported not being professionally connected to other male sex workers and limited disclosure about their work. Many were aware of the work-related risks to personal safety, including violence and robbery by clients. Perceived risk for HIV was mostly abstract and several exceptions to condom use with clients were noted. Alcohol use was reported as moderate but alcohol was consumed frequently in association with work. These data suggest that the most salient risks for male sex workers include professional isolation, threats to personal safety, limited perceived HIV risk and sub-optimal levels of condom use.     

Risk factors for measles virus infection and susceptibility in persons aged 15 years and older in China: A multi-site case-control study, 2012–2013

IntroductionEndemic measles persists in China, despite >95% reported coverage of two measles-containing vaccine doses and nationwide campaign that vaccinated >100 million children in 2010. An increasing proportion of infections now occur among adults and there is concern that persistent susceptibility in adults is an obstacle to measles elimination in China. We performed a case-control study in six Chinese provinces between January 2012 to June 2013 to identify risk factors for measles virus infection and susceptibility among adults.MethodsPersons ≥15 years old with laboratory-confirmed measles were age and neighborhood matched with three controls. Controls had blood specimens collected to determine their measles IgG serostatus. We interviewed case-patients and controls about potential risk factors for measles virus infection and susceptibility. Unadjusted and adjusted matched odds ratios and 95% confidence intervals (CIs) were calculated via conditional logistic regression. We calculated attributable fractions for infection for risk factors that could be interpreted as causal.Results899 cases and 2498 controls were enrolled. Among controls, 165 (6.6%) were seronegative for measles IgG indicating persistent susceptibility to infection. In multivariable analysis, hospital visit and travel outside the prefecture in the prior 1–3 weeks were significant risk factors for measles virus infection. Occupation and reluctance to accept measles vaccination were significant risk factors for measles susceptibility. The calculated attributable fraction of measles cases from hospital visitation was 28.6% (95% CI: 20.6–38.8%).ConclusionsExposure to a healthcare facility was the largest risk factor for measles virus infection in adults in China. Improved adherence to hospital infection control practices could reduce risk of ongoing measles virus transmission and increase the likelihood of achieving and sustaining measles elimination in China. The use of control groups stratified by serological status identified distinct risk factors for measles virus infection and susceptibility among adults.     

Risk factors for measles in children aged 8 months–14 years in China after nationwide measles campaign: A multi-site case-control study, 2012–2013

IntroductionEndemic measles persists in China, despite >95% reported coverage of two measles-containing vaccine doses and nationwide campaign that vaccinated more than 100 million children in 2010. In 2011, almost half of the 9943 measles cases in China occurred in children eligible for measles vaccination. We conducted a case-control study during 2012–2013 to identify risk factors for measles infection in children aged 8 months–14 years.MethodsChildren with laboratory-confirmed measles were age- and neighborhood-matched with three controls. We interviewed parents of case and control infants on potential risk factors for measles. We calculated adjusted matched odds ratios and 95% confidence intervals of risk factors. We calculated attributable fractions for risk factors that could be interpreted as causal and vaccine efficacy (VE) for the measles containing vaccine (MCV) used in the Chinese immunization program.ResultsIn all, 969 case-patients and 2845 controls were enrolled. In multivariable analysis, lack of measles vaccination both overall (mOR 22.7 [16.6, 31.1] and when stratified by region (east region, mOR 74.2 [27.3, 202]; central/western regions mOR 17.4 [12.5, 24.3]), hospital exposure (mOR 63.0, 95% CI [32.8, 121]), and migration among counties (overall mOR 3.0 [2.3, 3.9]) were significant risk factors. The calculated VE was 91.9–96.1% for a single dose of MCV and 96.6–99.5% for 2 doses.ConclusionsLack of vaccination was the leading risk factor for measles infection, especially in children born since the 2010 supplementary immunization activity. Reducing missed vaccination opportunities, improving immunization access for migrant children, and strengthening school/kindergarten vaccine checks are needed to strengthen the routine immunization program and maintain progress toward measles elimination in China.     

Dietary factors and oral cancer: a case-control study in Greater Metropolitan São Paulo, Brazil

Dietary factors associated with oral cancer were investigated in a case-control hospital-based study in the city of S?o Paulo, Brazil, from 1998 to 2002. A total of 835 subjects, 366 with histologically confirmed incident cases of oral-cavity or pharyngeal cancer and 469 controls participated in the study. Dietary data were collected with a food frequency questionnaire (FFQ). Odds ratios (OR) and 95% confidence intervals (95%CI) were obtained from unconditional logistic regression, adjusted for potential confounders. Inverse associations with risk of oral cancer were found for the highest intake of beans, OR = 0.37 (95%CI: 0.22-0.64), raw vegetables, OR = 0.51 (95%CI: 0.29-0.93) and the intermediate tertile of rice and pasta intake, OR = 0.56 (95%CI: 0.38-0.83). Positive associations were observed for the highest intake of eggs, OR = 1.84 (95%CI: 1.23-2.75), potatoes, OR = 2.22 (95%CI: 1.53-3.25), and milk, OR= 1.80 (95%CI: 1.09-2.98). Some traditional Brazilian foods like rice and beans emerged as protective factors against oral cancer, independently of other risk factors.     

Gender differences in carpal tunnel syndrome? occupational and non-occupational risk factors in a population-based case-control study

PURPOSE: To determine the role of occupational and personal risk factors of carpal tunnel syndrome (CTS) separately in men and women.METHODS: Men (n = 404) and women (n = 404) younger than 65 years with first surgery for CTS in 1995/96 were sampled at random from the Bremen population (0.65 million) and matched to controls by age and gender sampled from the population registry. A self-administered questionnaire with 77 questions inquired about personal factors and activities during work and private environment (response: 60% of eligible cases and 52% in controls, respectively).RESULTS: CTS risk increased with body mass index (BMI): odds ratio for each unit of BMI [kg/m(2)] OR(men) = 1.13; (95%-confidence-limits CL(men) 1.06, 1.20), OR(women) = 1.09 (CL(women) 1.04, 1.14). Multivariate analysis adjusting for BMI showed more pronounced risks in men compared with women for repetitive movements of the hand: OR(m) = 2.89 (CL 1.82, 4.58); OR(w) = 2.10 (CL 1.37, 3.22), for forceful grip: OR(m) = 2.69 (CL 1.70, 4.27); OR(w) = 2.29 (CL 1.43, 3.66), but not for household chores: OR(m) = 0.64 (CL 0.40, 1.03); OR(w) = 0.88 (CL 0.34, 2.29). Women worked less hours per week than men but manual exposures remained more relevant in men after adjustment. Exposure-response-relationships could be demonstrated for all work related exposures. Women were at higher risk for CTS if they had had more than two births or a history of hysterectomy. Adding these factors to the logistic model still showed an association between manual work and CTS. Blinded expert rating (manual vs. non-manual) of jobs held by respondents and non-respondents and by cases and controls did not reveal relevant selection effects or recall-bias.CONCLUSIONS: CTS is a work related disease in both men and women, the fraction attributable to work in the Bremen population under age 65 is estimated to be 33% in men and 15% in women. Funding: German Federal Ministry for Education & Research: 01 EG 9512.     

Risk factors associated with St. Louis encephalitis seroprevalence in two populations from Córdoba, Argentina

St. Louis encephalitis virus (SLEV) is endemic in Argentina. The first outbreak was recorded in Córdoba during the late summer of 2005. This study analyzes the association between social and demographic factors and other variables related to exposure to mosquitoes with SLEV infection in 264 individuals who attended two health centers in the city of Córdoba during the period December 2004-January 2005. Multiple logistic regression models were used to estimate the risk coefficients. The seroprevalence was 12.9%, similar to that in previous reports. Risks of infection were associated with the presence of garbage dumps near dwellings, the practice of outdoor activities at night and place of residence. Risk for older people (60-80 years old) was moderate. The identification of risk factors related to SLEV infection would be useful to improve programs for vector control and community health.     

Risk factors for cytomegalovirus seropositivity in a population of day care educators in Montréal, Canada

BACKGROUND: Horizontal transmission of cytomegalovirus (CMV) is common in the day care setting. Day care educators appear to be at a high risk of infection; however, studies are limited. AIMS: To determine the proportion of CMV-seropositive female educators in the day care setting and to identify associated risk factors. METHODS: Educator- and day care-level risk factors for CMV seropositivity were obtained by questionnaires from day care educators and directors, respectively. Sera were collected from educators and analyzed by enzyme-linked immunosorbent assay. Significant independent risk factors for CMV seropositivity were determined using a multivariable logistic regression model which was fitted using the generalized estimating equation method. RESULTS: CMV seroprevalence in 473 female educators from 81 day care centers in Montréal, Canada, was 57%. Significant risk factors for CMV seropositivity were (i) increasing age (OR5-yr = 1.19; 95% CI = 1.05-1.35), (ii) low-income country of birth (OR = 10.23; 95% CI = 2.64-39.50) or middle-income country of birth (OR = 4.99; 95% CI = 2.39-10.40), (iii) having > or =2 children of their own (OR = 1.98; 95% CI = 1.19-3.31) and (iv) child-to-educator ratio >6 (18-35 months old) in a day care center (OR = 1.87; 95% CI = 1.25-2.81). CONCLUSIONS: Day care educators have risks for CMV infection related to their work in the day care setting, as well as personal risk factors. A review of current guidelines for the prevention of CMV infection in day care is needed to ensure that recommendations are evidence based.     

Risk factors for vitamin D deficiency in women aged 20–50 years consulting in general practice: a cross-sectional study

Abstract

Objective: Vitamin D deficiency is often unidentified, although treatment is simple and inexpensive. Our objective was to estimate the influence of concealing clothes and other risk factors for vitamin D deficiency in women aged 20 to 50 years consulting general practitioners. Methods: 13 GPs in the Rhone Alps area planned to recruit 300 women (100 veiled and 200 non-veiled) from January to March 2008. Serum 25(OH)D and PTH were measured in one single laboratory (Biomnis^®) by a radio-immunoassay method. A survey was administered about dietary habits, sun exposure, and quality of life. Results: Among 247 women enrolled, 196 were analysed: 61 wearing concealing clothes (31.2%) and 135 without (68.8%). As expected, 25(OH)D serum level was significantly lower in covered women (20.1 versus 38.9 nmol/l P < 0.001). Of women who did not wear concealing clothing, 39.3% had severe hypovitaminosis D (25(OH)D concentration < 30 nmol/l). Women wearing concealing clothes had more often other known risk factors such as dark skin (P < 0.001), less sunlight exposure, or a higher Body Mass Index (P = 0.009). Besides concealing clothing (OR 6.37, 95% CI: 1.35–30.09), multivariate analyses revealed two independent risk factors for vitamin D deficiency: no full-body sun exposure (OR: 3.06, 95% CI: 1.18–7.94) and no outdoor sports (OR: 2.81, 95% CI: 1.11–7.12) for threshold 52 nmol/l.

Conclusion: Young women consulting their GP had hypovitaminosis D more often than expected. Besides concealing clothing, absence of full body sun exposure during summer and of outdoor sports practice could suggest a possible vitamin D deficiency.     

Potential Bridges of Heterosexual HIV Transmission from Drug Users to the General Population in St. Petersburg,Russia: Is it Easy to be a Young Female?

The epidemic of HIV in St. Petersburg, which is currently concentrated among injection drug users (IDUs), may be penetrating into the general population. Non-IDUs who have IDU sex partners (SP) could be potential bridges in an expanding epidemic. To investigate potential bridges, we accrued a convenience sample of 288 non-IDUs whose HIV diagnosis was attributed to sexual transmission and we determined the proportion that had IDUs among their SP. Having IDU SP ever (lifetime) and IDU SP in the last year were the key variables for the analysis of potential bridges in this study. The interaction of gender and age was found to be a significant predictor of having lifetime IDU SP (p?=?0.006, χ ² test) and IDU SP in the last year (p?=?0.05, χ ² test): females aged 26 and younger were more likely to have both lifetime IDU SP and IDU SP in the last year. Among the group of young females, 46% reported ever having an IDU SP. Out of young women reporting ever having an IDU SP, 85% also reported at least one lifetime non-IDU SP. Among the females aged 26 or younger, a lower level of education (odds ratio [OR]?=?2.7, confidence interval [CI]?=?1.1–6.7), being born in St. Petersburg (OR?=?2.9, CI?=?1.2–7.2), and alcohol use in the last 30 days (OR?=?3.5, CI?=?1.3–9.6) were significant correlates for ever having had an IDU SP. Urgent efforts are necessary to expand HIV prevention to target the potential bridging population to prevent further transmission.     

Pertussis in infants under one year old: Risk markers and vaccination status—A case-control study

BackgroundPertussis is a contagious bacterial disease causing substantial health burden. Pertussis-related morbidity and mortality are highest in young infants. We investigated risk markers for pertussis and vaccination status in infants.MethodsReported pertussis cases under one year old during 1998–2011 in the Jerusalem district were matched to controls by birthdate and residence. Data sources included epidemiological investigations, health records and vaccination records (number and dates of DTPDTaP doses scheduled at 2, 4, 6 months). Vaccine effectiveness was calculated by number of vaccine doses stratified by age group. Timeliness of vaccine doses was also evaluated.ResultsThe study population included 1268 infants under 1 year: 317 pertussis cases and 951 age-matched controls (mean age 3.95 ± 3, median 2.9 months). Low birthweight (<2500 g, 12.3% in cases vs. 6.3% in controls) and high birth order (4th and above) were found to be independent risk markers. Male gender and low socio-economic status were more frequent among cases. Some 40% of the cases (127/317) were hospitalized, most of them (111/127, 87.4%) were under 4 months (mean age 2.42 ± 2.05, median 1.8 months).The distribution of the number of pertussis vaccine doses 0, 1, 2 and 3 differed considerably being 42.2%, 32.7%, 15.6%, 9.5% vs. 13.7%, 41.9%, 22.9%, 21.5% among cases and controls (≥2 m), respectively. The overall vaccine effectiveness found was 72.9%, 76.1% and 84.4%, for the 1st, 2nd and 3rd doses of a pertussis vaccine. The infant's age at the first dose of pertussis vaccine was recorded with follow-up until age 18 months. Delay was more common among cases with a lower proportion vaccinated—78.9% at 18 months vs. 99% in controls.ConclusionsSpecific risk markers for pertussis in young infants were identified. Reported pertussis cases over age 2 months were significantly more likely to be unvaccinated and have delayed vaccinations. The vaccine effectiveness increased with the number of vaccine doses.     

Potential Bridges of Heterosexual HIV Transmission from Drug Users to the General Population in St. Petersburg, Russia: Is it Easy to be a Young Female?

The epidemic of HIV in St. Petersburg, which is currently concentrated among injection drug users (IDUs), may be penetrating into the general population. Non-IDUs who have IDU sex partners (SP) could be potential bridges in an expanding epidemic. To investigate potential bridges, we accrued a convenience sample of 288 non-IDUs whose HIV diagnosis was attributed to sexual transmission and we determined the proportion that had IDUs among their SP. Having IDU SP ever (lifetime) and IDU SP in the last year were the key variables for the analysis of potential bridges in this study. The interaction of gender and age was found to be a significant predictor of having lifetime IDU SP (p = 0.006, χ ² test) and IDU SP in the last year (p = 0.05, χ ² test): females aged 26 and younger were more likely to have both lifetime IDU SP and IDU SP in the last year. Among the group of young females, 46% reported ever having an IDU SP. Out of young women reporting ever having an IDU SP, 85% also reported at least one lifetime non-IDU SP. Among the females aged 26 or younger, a lower level of education (odds ratio [OR] = 2.7, confidence interval [CI] = 1.1–6.7), being born in St. Petersburg (OR = 2.9, CI = 1.2–7.2), and alcohol use in the last 30 days (OR = 3.5, CI = 1.3–9.6) were significant correlates for ever having had an IDU SP. Urgent efforts are necessary to expand HIV prevention to target the potential bridging population to prevent further transmission.     

Risk factors for cancer of the uterine cervix in Propriá, Sergipe, Brazil

Cervical cancer is highly incident in poor regions of developing countries. It is related to lifestyle factors that lead to human papillomavirus (HPV) infection. The aim of the study was to assess which factors are important in the development of HPV infection and consequent cervical cancer in the community of Propriá, Sergipe, Brazil. To analyze the risk factors related to cervical cancer, a case-control study was performed, matching cases and controls for age, place of residence, and socioeconomic status. Twenty cases of carcinoma of the uterine cervix and 80 controls were identified. Cases had more pregnancies and a higher proportion of women who had not done Pap smears. Women in the two groups lived with promiscuous partners, had deficient knowledge about cervical cancer and its risk factors, and were predominantly illiterate. We concluded that in the community of Propriá, multiple pregnancies and failure to have Pap smears were associated with the occurrence of cervical cancer.     

Determinants of neonatal mortality: a case-control study in Fortaleza, Ceará State, Brazil

This case-control study with 132 cases and 264 controls aimed to determine predictors of neonatal mortality using hierarchical modeling. Cases were defined as newborns that died within 28 days of birth, and controls as the survivors, among infants of mothers living in Fortaleza, Ceará State, Brazil. Hierarchical logistic regression identified factors associated with neonatal death: maternal race, with brown/black race showing a protective effect (OR = 0.23; IC95%: 0.09-0.56), time spent from home to the hospital > 30 minutes (OR = 3.12; 95%CI: 1.34-7.25), time < 1h or > 10 hours between hospital admission and delivery (OR = 2.43; 95%CI: 1.24-4.76), inadequate prenatal care (OR = 2.03; 95%CI: 1.03-3.99), low birth weight (OR = 14.75; 95%CI: 5.26-41.35), prematurity (OR = 3.41; 95%CI: 1.29-8.98), and male gender (OR = 2.09; 95%CI: 1.09-4.03). In this case series, neonatal deaths were associated with the quality of prenatal care and direct care during labor.     

Risk factors for Helicobacter pylori infection in children: is education a main determinant?

To investigate potential risk factors associated with Helicobacter pylori (Hp) infection, we performed a case-control study in 167 consecutively selected hospitalized children in Salvador, Brazil. Hp infection was identified by the presence of IgG against Hp in serum samples. Data were gathered using a structured questionnaire, 38.3% children were found to be seropositive and classified as cases, and 61.7% were seronegative controls. After multivariate analysis, independent variables associated with Hp infection included: the educational attainment of the child's provider > or = 11 years (OR 0.1, 95% CI 0.01-0.9), poor garbage disposal service (OR 2.2, 95% CI 1.0-4.9), thumb sucking (OR 4.6, 95% CI 1.1-19.8), brushing teeth more than once a day (OR 5.6, 95% CI 1.8-17.7), having a pet dog (OR 2.5, 95% CI 1.0-6.1), and a history of chronic urticaria (OR 4.0, 95% CI 1.5-10.8). The risk factors identified are consistent with some, but not all, previous studies supporting either oral-oral or faecal-oral transmission of Hp. Our data suggested that a higher educational attainment might play an important role in preventing Hp infection.     

Risk factors for cortical, nuclear, and posterior subcapsular cataracts: the POLA study. Pathologies Oculaires Liées à l'Age

The POLA (Pathologies Oculaires Liées à L'Age) Study is a population-based study of cataract and age-related macular degeneration and their risk factors being carried out among 2,584 residents of Sète, southern France, aged 60-95 years. Recruitment took place between June 1995 and July 1997. Cataract classification was based on a standardized lens examination by slit lamp, according to Lens Opacities Classification System III. This paper presents results obtained from cross-sectional analysis of the first phase of the study. In polytomous logistic regression analyses, an increased risk of cataract was found for female sex (cataract surgery: odds ratio (OR) = 3.03; cortical cataract: OR = 1.67), brown irises (cortical, nuclear, and mixed cataracts: OR = 1.61), smoking (cataract surgery: OR = 2.34 for current smokers and OR = 3.75 for former smokers), known diabetes of 10 or more years' duration (posterior subcapsular, cortical, and mixed cataracts and cataract surgery: OR = 2.72), use of oral corticosteroids for at least 5 years (posterior subcapsular cataract: OR = 3.25), asthma or chronic bronchitis (cataract surgery: OR = 2.04), cancer (posterior subcapsular cataract: OR = 1.92), and cardiovascular disease (cortical cataract: OR = 1.96). Decreased risk of cataract was found with higher education (all types of cataract and cataract surgery: OR = 0.59), hypertension (cataract surgery: OR = 0.57), and high plasma retinol levels (nuclear and mixed cataracts and cataract surgery: OR = 0.75 for a 1-standard-deviation increase). Most of the risk factors identified in this study confirm the findings of other studies. The association of cataract with plasma retinol level requires further investigation.     

Risk factors for musculoskeletal symptoms among call center operators of a bank in São Paulo, Brazil

OBJECTIVE: Identify risk factors for musculoskeletal symptoms among call center operators of a bank in S?o Paulo, Brazil. METHODS: Ergonomic work analysis was carried out, involving work observation and interviews. Self-answered questionnaires performed by 108 call center operators. RESULTS: Women represented 88% of the call center operators, 70% of them were in the age bracket of 18 to 23 yr. Daily working time was 6-h with one 30 min break. Workers remained seated 95% of the time, typing and answering telephone calls. Men' s work consisted of more active telemarketing and women's of customer services. Among female operators the prevalence of neck/shoulder symptoms was 43% (95% CI, 33-53) and of wrist/hand was 39% (95% CI, 29-49). Risk factors associated with wrist/hand symptoms were: inadequate height of table (Odds ratio (OR) 3.67, 95% CI, 1.12-11.96) and to answer above 140 calls/d (OR 3.36, 95% CI, 1.16-9.71). Risk factors associated with neck/shoulder symptoms were making fewer rest breaks (OR 3.17, 95% CI, 1.11-8.97) and inadequate thermal comfort (OR 3.06, 95% CI, 1.09-8.62). CONCLUSIONS: Prevention of musculoskeletal disorders among call center operators requires an integrated approach including improved workstation design, thermal comfort environment, well-scheduled work-rest regime and realistic production goals.