Objective To analyze the epidemiological characteristics of Mycoplasma pneumoniae(MP)infection in children with acute respiratory tract infection in Haikou area and surrounding area to provide a scientific evidence for the prevention and treatment of MP infection in children.Methods A total of 1 699 children inpatients with acute respiratory tract infection in our hospital from 1 January to 1 December,2014 were collected.The serum MP antibody was detected.The MP infection status of different sites,genders,ages and months was retrospectively analyzed.Results Among 1 699 children patients with acute respiratory tract infection,the total positive rate of MP infection was 17.60％,in which male was 15.73％ and female was 21.59％,the positive rate of female was higher than that of male with statistical difference(P＜0.01).The lower respiratory infection rate was 18.75％ and upper respiratory tract infection was 13.70％,the difference was statistically significant(P＜0.05).The MP infection rates was common in children aged >1-4 years old,in which children aged >3-4 years old had the highest infection rate.MP infection was sporadic in the whole year and was highly epidemic in March and April.Conclusion MP was an important pathogen of acute respiratory tract infection for children in Haikou during 2014,and its epidemic characteristics were manifested by higher incidence in female than that in male.Children aged within 4 years old are a high onset group and MP infection occurs all year round,March and April are the relatively high onset period of MP infecting.

Objective To investigate the incidence of neonatal carnitine deficiency (PCD) in eight minority autonomous cities and counties in Hainan Province (Changjiang, Ledong, Dongfang, Baoting, Baisha, Qiongzhong, Wuzhishan and Lingshui). Methods A total of 18, 701 cases of newborn filter paper dried blood samples were collected from August 1, 2017 to July 31, 2018 in eight minority autonomous cities and counties in Hainan Province, including 10051 male infants and 8650 female infants. Tandem mass spectrometry and the non-derivatized multi-amino acid, carnitine and succinylacetone assay kits produced by PE were used to detect free carnitine (C0) and acylcarnitine (C2, C3, C16, C18, etc.).The carnitine spec-trum was reexamined with the recall of mothers and infants whose C0 was less than 10μmol/L. Blood sam-ples from those who were still low were sent to the Beijing McKinnon gene for genetic diagnosis, and the urine samples were sent to the Guangzhou Golden Field for urine gas chromatography. Results Among the 18701 newborns, 5 cases were diagnosed with PCD. The incidence of neonatal PCD was 2.67/10000 (5/18701). Two cases of Li mutation c.388GA, two cases of Han mutation P.R254X and one case of Miao mutation P. Y84N were confirmed by gene detection. The confirmed children were treated with L-carnitine to avoid metabolic disorders or myocardial and skeletal muscle damage. Conclusions The incidence of neonatal PCD is high in eight cities and counties in Hainan Province. The mutation sites of neonatal PCD are different in Li and Han. The tandem mass spectrometry screening of PCD can guarantee the quality of the birth population.