Analysis on the response measures and outcomes of four epidemics of infectious diseases in Shanghai based on a time axis / 上海预防医学

Objective To compare the response measures and outcomes of SARS-CoV(2003), H1N1 influenza(2009), H7N9 influenza(2013)and COVID-19(2020)in Shanghai and provide scientific evidence for the emergency response of public health emergencies. Methods We compared the response measures and outcomes of the four epidemics in Shanghai in the aspects of government response, prevention and control system, scientific and technological support, social mobilization and prevention effects, using critical incident analysis based on the time axis of the epidemics from literature review. Results In response to the four epidemics of infectious diseases occurred in 2003-2020, Shanghai has generally made some significant effort and flexible measures in the first month of the epidemics, including"closure of live poultry markets"and"three closed-loops and four 100% coverage"and other specific prevention and control measures, which have enhanced the prevention and control system. However, we identified that the construction of prevention and control system for public health emergencies remained inefficient, compared to rapid economic development. The majority of the construction measures were principally post-epidemic. In addition, there were many challenges, such as passive response, temporary response teams and measures, and difficulties in the flexible bottom-up response for residents, families and industries without standard operating procedure and guidelines. Conclusion It may be an effective measure for the prevention and control of infectious diseases to build joint prevention and control measures with mass participation and regular drills, in the perspectives of strategic, tactical and operational levels of epidemic prevention and control.

Investigation on the levels of carbon-, nitrogen-, iodine-containing disinfection by-products in a water plant in Jiangsu province, China / 中华预防医学杂志

<p><b>OBJECTIVE</b>This work aimed to investigate the carbon-, nitrogen-, iodine-containing disinfection by-products (DBPs) formation and pollution situation in different treatment processes and pipe water of a water plant in Jiangsu province China.</p><p><b>METHODS</b>12 water samples were collected from raw water, different time points after the addition of chlorine, finished water and pipe water in July, 2011. Trihalomethanes (THM(4)), haloacetic acids (HAA(6)), haloacetonitriles (HAN(s)), chloropicrin (CPs), haloketones (HK(s)), iodoform (IF) and iodoacetic acid (IAA) were detected by gas chromatography with electron capture detector (GC-ECD) after liquid-liquid extraction. Nitrosamines (NAms) were detected by gas chromatography with mass spectrometer (GC-MS) after solid-phase extraction. The concentration of DBPs was represented as the mean of duplicate samples.</p><p><b>RESULTS</b>Most DBPs were found in water treatment processes except dibromochloromethane (0.61 µg/L), chloroform (1.64 µg/L) and N-nitrosodimethylamine (3.06 ng/L), which were detected in raw water. Pre-chlorination formed HAA(6) (5.01 µg/L), HKs (0.66 µg/L), HANs (0.57 µg/L) and NAms (98.09 ng/L). Chlorination and post-chlorination led to a dramatic increase in the levels of THM(4), HAA(6) (70.31 and 43.71 µg/L, respectively), while Nams didn't increase. In finished water, bromodichloromethane (34.12 µg/L) had the highest concentration among THM(4) (70.31 µg/L), and so was trichloroacetic acid (13.45 µg/L) among HAA(6) (43.71 µg/L). Levels of HANs, HKs, and CPs were 14.96, 2.32, 0.96 µg/L, respectively. Levels of N-nitrosodimethylamine and N-nitrosodipropylamine were 21.22, 69.43 ng/L, respectively. IAA, IF and other six NAms including N-nitrosomethylethylamine, N-nitrosodiethylamine, N-nitrosopyrrolidine, N-nitrosomorpholine, N-nitrosopiperidine and N-nitrosodibutylamine were not detected in all water samples.</p><p><b>CONCLUSION</b>Levels of DBPs in this water plant are relative high.and measures should be taken to control DBPs.</p>

Thyroid disruption induced by pentachlorophenol / 中华预防医学杂志

<p><b>OBJECTIVE</b>To assess thyroid disruption induced by sodium pentachlorophenol (PCP) using Organization for Economic Co-operation and Development (OECD) recommended TG 407 method.</p><p><b>METHODS</b>A total of 30 specific pathogen free (SPF) SD adult male and female rats were randomly divided into 3 groups, and treated with water, 0.33 and 30 mg x kg(-1)x d(-1) of PCP-Na by oral gavage for consecutive 28 days, respectively. After final treatment, histological changes of thyroid were observed by hematoxylin-eosin stain, and the levels of thyroid hormones (total thyroxine (TT(4)), free thyroxine (FT(4)), total triiodothyronine (TT(3)), and free triiodothyronine (FT(3))) were determined by radioimmunoassay. The expression levels of thyroid receptors (TRalpha and TRbeta) mRNA and deiodinases (DioI, DioII and DioIII) mRNA in liver were analyzed by RT-PCR.</p><p><b>RESULTS</b>In high dose group, liver weight coefficient of male and female rats were (4.82 +/- 0.42)% and (4.99 +/- 0.17)%, increased by 36.2% (t = 7.338, P < 0.01) and 41.8% (t = 8.955, P < 0.01), compared to control group ((3.54 +/- 0.14)%, (3.52 +/- 0.19)%), respectively, while the significant changes of kidney or thyroid weight were not observed. In high dose group, the levels of TT(4) and FT(4) in serum of male rats were (64.95 +/- 7.16) nmol/L and (8.16 +/- 2.29) pmol/L, and decreased by 26.6% (t = -3.999, P < 0.01) and 42.3% (t = -4.112, P < 0.01) compared to control group ((88.48 +/- 6.99) nmol/L, (14.13 +/- 1.68) pmol/L). In the same group, FT(4) in serum of female rats was (4.94 +/- 0.89) pmol/L, decreased by 55.5% (t = -3.380, P = 0.012) compared to control group ((11.10 +/- 3.40) pmol/L) and TT(3) and FT(3) in serum of female rats were (1.92 +/- 0.24) nmol/L and (3.05 +/- 0.79) pmol/L, increased by 74.5% (t = 5.263, P < 0.01) and 55.6% (t = 3.495, P < 0.01) compared to control group ((1.10 +/- 0.23) nmol/L, (1.96 +/- 0.32) pmol/L), respectively. PCP-Na didn't affect the expression levels of TRalpha, TRbeta, DioIII mRNA in high dose group, while DioII expression of male rats (0.209 +/- 0.017) down-regulated by 79.2% (t = -5.426, P < 0.01) compared to control group (1.006 +/- 0.137), and DioI expression of female rats (1.844 +/- 0.189) up-regulated by 66.6% (t = 4.359, P < 0.01) compared to control group (1.005 +/- 0.083), indicating DioI and DioII poss different sensitivity to adverse effects induced by PCP-Na between male and female rats. The histopathological results showed that PCP-Na could give rise to hyperplasia of the follicular epithelium cells, and the depletion of colloid. There were no significant changes in serum THs levels and expression of TRalpha, TRbeta, DioI-IIImRNA in low dose group. However, sporadic lymphocytic infiltration, follicles amplification in part and slightly increased in thickness of follicular cells were observed in this group.</p><p><b>CONCLUSION</b>PCP is a kind of thyroid disrupting chemical.</p>