Analysis on influencing factors that leading to nonspecific responses to indeterminate results of HIV antibodies / 中华流行病学杂志

Objective: To identify the influencing factors that leading to nonspecific responses to indeterminate HIV antibody tests, to provide scientific evidence for the differential diagnosis of HIV infection and control strategy. Methods: A case control study was conducted. The samples of HIV antibody indeterminate in confirmed Western blot (WB) tests, but were negative in HIV nucleic acid tests, were collected as HIV antibody indeterminate group from WB results of HIV confirmatory laboratories of Fujian province in 2015-2016. The general population matched group with HIV antibody screening negative samples and WB negative matched group with WB negative samples were selected as the two compared groups by matching gender and age from HIV antibody screening in Fujian province in the same period. Blood concentrations of hepatitis B surface antigen (HBsAg), anti-hepatitis C virus (HCV) antibody, anti-treponema pallidum (TP) antibody, antinuclear antibody (ANA), anti-human T-cell leukemia virus (HTLV) antibody, and alpha-fetoprotein (AFP) were detected by using enzyme-linked immunosorbent assay (ELISA). χ(2) test and multivariate non-conditional logistic regression analysis were performed to identify the influencing factors that leading to nonspecific responses, to indeterminate HIV antibody tests. Results: A total of 13 WB band patterns were observed in 110 HIV antibody indeterminate samples, in which a single p24 band (58.18%, 64/110), a single gp160 band (17.27%, 19/110) and a single p17 band (7.27%, 8/110) were the three most common patterns. The positive rate of anti-TP antibody was significantly higher in HIV antibody indeterminate samples than general population control group and WB negative control group (10.91%, 12/110 vs. 1.77%, 4/226 and 3.64%, 4/110), compared with two control groups (χ(2)=13.627 and 4.314, P<0.05). The positive rate of AFP was significantly higher in HIV antibody indeterminate samples than general population control group (18.18%, 20/110 vs. 0.44%, 1/226, χ(2)=39.736, P<0.05), the different was not significant compared with WB negative control group (18.18%, 20/110 vs. 23.64%, 26/110, χ(2)=0.990, P>0.05) While no significant differences were found between HIV antibody indeterminate group and two control groups in terms of the positive rates of ANA, HBsAg, anti-HCV antibody or anti-HTLV antibody. Conclusions: The influencing factors that leading to nonspecific responses to indeterminate HIV antibody tests appeared complicate, and the anti-TP antibody positivity might be an influencing factor responsible for nonspecific responses to indeterminate HIV antibody tests.

Dynamic path analysis on life course epidemiology / 中华流行病学杂志

In the studies of modern epidemiology, exposure in a short term cannot fully elaborate the mechanism of the development of diseases or health-related events. Thus, lights have been shed on to life course epidemiology, which studies the exposures in early life time and their effects related to the development of chronic diseases. When exploring the mechanism leading from one exposure to an outcome and its effects through other factors, due to the existence of time-variant effects, conventional statistic methods could not meet the needs of etiological analysis in life course epidemiology. This paper summarizes the dynamic path analysis model, including the model structure and significance, and its application in life course epidemiology. Meanwhile, the procedure of data processing and etiology analyzing were introduced. In conclusion, dynamic path analysis is a useful tool which can be used to better elucidate the mechanisms that underlie the etiology of chronic diseases.

Epidemiological characteristics of Coxsackie virus A16 caused hand foot and mouth disease cases in Guangdong province, 2012-2016 / 中华流行病学杂志

Objective: To analyze the epidemiological characteristics of hand foot and mouth disease (HFMD) cases caused by Coxsackie virus A16 (Cox A16) in Guangdong province from 2012 to 2016. Methods: The data of mild HFMD cases caused by Cox A16 were collected from 8 sentinel hospitals in 8 prefecture-level cities in Guangdong to estimate Cox A16 infection status and its population and time distribution characteristics. Results: (1) The highest estimated incidence of Cox A16 infection was in 2014 (113.0/100 000), followed by 2016 (86.4/100 000) and 2012 (79.1/100 000), while the estimated incidence was lower in 2015 (29.0/100 000) and 2013 (28.8/100 000). (2) Cox A16 was confirmed to be the predominant pathogen causing HFMD outbreaks (54.6%, 89/163). The number of outbreaks in the year with high incidence (28 outbreaks) was 11.2 times higher than that in the year with low incidence (2.5 outbreaks). (3) Across all age groups, the annual estimated incidence of Cox A16 infection decreased with age (trend χ(2)=853 905.63, P<0.01). The incidence was highest in age group 1 year (1 449.2/100 000), followed by that in age group 3 years (1 097.0/100 000), in age group 2 years (1 083.5/100 000), in age group 4 years (687.8/100 000) and in age group 0 year (604.9/100 000). Among the age groups <12 months, the estimated incidence increased with age (trend χ(2)=5 541.77, P<0.01), which was highest in age group 11-months (2 105.1/100 000), followed by that in age groups 10-months (1 448.6/100 000), 9-months (938.3/100 000), 8-months (703.3/100 000) and 6-months (664.6/100 000). (4) The annual incidence peak was during May (143.9/100 000)-June (131.5/100 000). Conclusion: The prevalence of Cox A16 infection differed with year in Guangdong during 2012-2016. When the incidence of Cox A16 infection was high, more outbreaks occurred. The prevalence occurred mainly in nurseries and kindergartens from May to June each year. Children aged 0-4 years were the high risk group for Cox A16 infection, children aged 6-11 months were at high risk for Cox A16 infection.

Association between total cholesterol and risk of lung cancer incidence in men: a prospective cohort study / 中华流行病学杂志

Objective: To assess the association and intensity of baseline TC level with the incidence of lung cancer in men in China. Methods: Since May 2006, all the male workers, including the employees and the retirees in Kailuan Group were recruited in the Kailuan male dynamic cohort study. Information about demographics, medical history, anthropometry and TC level were collected at the baseline interview, as well as the information of newly-diagnosed lung cancer cases during the follow-up period. According to guidelines for blood lipids in Chinese adults and the distribution in the population, TC level was classified into five groups as followed: <160, 160-, 180-, 200- and ≥240 mg/dl, with the second quintile group (160- mg/dl) serving as the referent category. Cox proportional hazards regression model and restricted cubic spline (RCS) model were used to evaluate the association and the nonlinear association between baseline TC level and the risk of lung cancer in the men. Results: By December 31, 2014, for the 109 884 men, a follow up of 763 819.25 person-years was made with a median follow-up period of 7.88 years. During the follow up, 808 lung cancer cases were identified. After adjustment for age, education level, income level, smoking status, alcohol consumption level, history of dust exposure, FPG level and BMI, HR (95%CI) of lung cancer for men with lower TC level (<160 mg/dl) and higher TC level (≥240 mg/dl) were 1.34 (1.04- 1.72) and 1.45 (1.09-1.92), respectively, compared with men with normal TC level (160- mg/dl). The results didn't change significantly after exclusion of newly diagnosed cancer cases within 2 years of follow up and subjects with the history of hyperlipidemia. Conclusion: Our results showed that TC might be associated with higher risk of lung cancer. Men with lower TC level or higher TC level had higher risk for lung cancer. Keep moderate TC level might be one of the effective precaution for the prevention of lung cancer.

Alcohol consumption and the risk of lung cancer in males: a prospective cohort study / 中华流行病学杂志

Objective: To investigate the association between alcohol consumption and lung cancer risk in Chinese males. Methods: Information on alcohol consumption and outcomes were collected on a biennial basis among males in Kailuan Cohort (2006-2015). In addition, electronic databases of hospitals affiliated to Kailuan Community, Insurance Systems of Kailuan Community and Tangshan were also used for supplementary information retrieval. Cox proportional hazards regression models were used to evaluate the hazard ratio (HR) and 95%CI of baseline frequency and type of alcohol consumption associated with lung cancer risk in males. Non-drinkers were used as control group. Results: A total of 101 751 males were included and 913 new lung cancer cases were identified in the Kailuan male cohort study, with a total follow-up time of 808 146.56 person-years and a median follow-up time of 8.88 years by 31 December 2015. After adjusting for potential confounding factors, the HR of former drinkers, occasional drinkers (<1/day) and drinkers (≥1/day) were 1.30 (95%CI: 0.90-1.88), 0.80 (95%CI: 0.64-1.01) and 1.04 (95%CI: 0.85-1.27), respectively, compared with non-drinkers. In addition, drinking beer/red wine (HR=0.91, 95%CI: 0.69-1.20) and white wine (HR=0.99, 95%CI: 0.83-1.19) showed no significant association with lung cancer. The results were similar when stratified analysis were conducted. Conclusion: Our study results don't support the hypothesis that alcohol consumption is significantly associated with the risk of lung cancer in males.

Epidemiological characteristics of outbreaks of norovirus-GⅡ.2, GⅡ.17 and GⅡ.4/Sydney in Guangdong province, 2013-2017 / 中华流行病学杂志

Objective: To understand the epidemiologic characteristics of outbreaks, caused by norovirus-GⅡ.2、GⅡ.17 and GⅡ.4/Sydney in Guangdong Province from 2013 to 2017 and to provide scientific evidence for epidemic prevention and control. Methods: Incidence data of norovirus outbreaks in Guangdong from January 1(st) 2013 to November 30(th) 2017 were collected from Public Health Emergency Management Information System. RT-PCR was performed for every case of each outbreak to detect norovirus nucleic acid and gene sequencing was conducted to identify the genotype of norovirus. Characteristics of norovirus GⅡ.2, GⅡ.17 and GⅡ.4/Sydney outbreaks were analyzed. Directly standardized method was used to calculate the proportion of symtoms as diarrhea and vomitting. Results: From January 1(st) 2013 to November 30(th) 2017, a total of 167 norovirus outbreaks were reported in Guangdong, and 115 outbreaks were caused by norovirus GⅡ.2, GⅡ.17 and GⅡ.4/Sydney respectively. The outbreaks caused by norovirus GⅡ.2 accounted for 39.68% (25/63) in primary schools, 28.57% (18/63) in child care settings, 25.40% (16/63) in middle schools and 6.35% (4/63) in universities. Outbreaks caused by norovirus GⅡ.17 accounted for 41.03% (16/39) in middle schools, 20.51% (8/39) at workplaces, 15.38% (6/39) in primary schools, 12.82% (5/39) in universities, 5.13% (2/39) in communities and child care settings respectively. The outbreaks caused by norovirus GⅡ.4/Sydney accounted for 53.85% (7/13) in universities, 15.38% (2/13) in child care settings and at workplaces respectively, 7.69%(1/13) in primary schools and middle schools respectively. The outbreaks caused by norovirus GⅡ.2 had 77.78% (49/63) of contact transmission, 17.46% (11/63) of food-borne transmission. The outbreaks caused by norovirus GⅡ.17 showed 53.85% (21/39) of food-borne transmission, 15.38% (6/39) of contract transmission, 12.82% (5/39) of water-borne transmission. The outbreaks caused by norovirus GⅡ.4/Sydney had 53.85% (7/13) of food-borne transmission, 38.46% (5/13) of the contact transmission. In terms of the clinical manifestations, the standardized proportion of vomit was 73.76% and the proportion of diarrhea was 42.85% in cases infected with norovirus GⅡ.2, the proportion of standardized of vomit was 76.37% and the proportion of diarrhea was 51.40% in cases infected with norovirus GⅡ.17, with the standardized proportion of vomit was 54.10% and the proportion of diarrhea was 55.95% in cases infected with norovirus GⅡ.4/Sydney. Conclusions: The outbreaks caused by norovirus GⅡ.2 through contact transmission mainly occurred in primary schools, child care settings and middle schools. The outbreaks caused by norovirus GⅡ.17 through food-borne transmission mainly occurred in middle schools and at workplaces. The outbreaks caused by norovirus GⅡ.4/Sydney food-borne transmission and contact mainly occurred in universities.