Epidemiological analysis of viral hepatitis A in China, 2004-2015 / 中华预防医学杂志

Objective@#To analyze the epidemiological characteristics of hepatitis A cases in China from 2004 to 2015.@*Methods@#Data of hepatitis A were reported through national notifiable disease information reporting system, which covered the 31 provinces (Hong Kong, Macau and Taiwan excluded). The inclusion criteria was: date of illness onset was between January 1st 2004 and December 31st 2015, the status of reported card was confirmed, the case was classified as laboratory confirmed or clinical diagnosed, the disease was Hepatitis A. The information such as sex, date of birth, date of illness onset, place of residence was collected. The data was divided into three phases, 2004-2007, 2008-2011, 2012-2015, which represented the phase before expanded program on immunization (EPI), first 4 years after EPI, second 4 years after EPI.@*Results@#From 2004 to 2015, there were totally 574 697 hepatitis A cases in China, the mean annual incidence was 3.62/100 000. The risk ratio of hepatitis A in 2015 was 0.23 when compared with 2004. Sichuan, Xinjiang and Yunnan contributed to 27.27% of the total cases in China. In 2012-2015, the incidence of western (3.46/100 000) region was significantly higher than that in central (1.21/100 000) and eastern (1.08/100 000) regions. From 2004-2015, number of cases in each age group declined greatly, with number of cases declining from 43 711 to 5 938 in the age group of 5-9 years, from 29 722 to 3 438 in 10-14, from 23 212 to 3 646 in 15-19. The number of cases declined from 24 079 to 10 304 in the age group of 0-4 (declined by 57.21%), but in 2012-2015, the incidence of 0-4 age group was still the highest, with 77.72% cases in Xinjiang and Sichuan. Famers, students and scattered children accounted for 69.95% of total cases, with student cases declined from 24.08% (2004-2007) to 8.67% (2012-2015).@*Conclusion@#The incidence of hepatitis A in China is decreasing year by year, the risk has been decreasing to a relatively low level. However, in western regions and children under age five, the risk is still high. Precision intervention is needed for further prevention and control of hepatitis A.

Seroepidemiología de la hepatitis A en México: sensor de inequidad social e indicador de políticas de vacunación / Seroepidemiology of hepatitis A in Mexico: a detector of social inequity and monitor of immunization policies

OBJETIVO: Estudiar la distribución y frecuencia de los anticuerpos contra el virus de la hepatitis A en una muestra probabilística en México con representatividad estatal, así como analizar los factores de riesgo y los patrones epidemiológicos. MATERIAL Y MÉTODOS: A partir de la Encuesta Nacional de Salud se estudiaron 4 907 sueros seleccionados de forma aleatoria para anticuerpos contra VHA mediante ensayo inmunoenzimático. Los sueros se recolectaron de noviembre de 1999 a junio del 2000 a nivel nacional. RESULTADOS: Se encontró seroprevalencia general de 81.3 por ciento (IC 78.6-84.2), y los resultados expandidos permiten inferir que existen 78.7 millones de mexicanos infectados. Los factores de riesgo en menores de nueve años incluyen residir en entidades sureñas (RM= 5.3), localidades rurales (RM= 3.1), provenir de familia con bajos ingresos (RM= 2.4) y habitar viviendas con acceso limitado a servicios sanitarios (agua, RM= 2.5; drenaje, RM= 2.7). CONCLUSIONES: Los patrones de transmisión heterogéneos y las diferencias en las pre-valencias de infección indican inequidad en las poblaciones estudiadas, explicables por diferencias en las condiciones sanitarias y sociales. Se discuten las ventajas de intervenciones poblacionales tales como la vacunación y el fortalecimiento de las condiciones sanitarias y socioeconómicas.

OBJECTIVE: Hepatitis A Virus (HAV) in Mexico has traditionally been considered a disease with a homogeneous pattern of transmission, high rates of infection at early ages, and infrequent complication rates. The purpose of this study was to take advantage of the 2000 NHS, a probabilistic population-based survey, in order to describe the seroepidemiology of HAV infection in Mexico. MATERIAL AND METHODS: This study is based on information obtained from the National Health Survey that was conducted in 2000. The present report is based on 4 907 randomly selected samples that were studied to determine the prevalence of HAV antibodies using immunoenzymatic assay. Sera were collected from November 1999 to June 2000. RESULTS: Seroprevalence among the general population was 81.3 percent (CI95 percent: 78.6-84.2); expanded results allow the inference that 78.7 million Mexicans have been infected by this agent. Risk factors for HAV among children younger than nine years of age are the following: residence in southern states OR=5.3, residence in rural communities OR= 3.1, low-income family OR= 2.4 and living in households with limited access to sanitary facilities (water OR= 2.5 and sewage OR= 2.7). CONCLUSIONS: Results of this study demonstrate that HAV transmission patterns are heterogeneous and that differentials in the prevalence of infection are due to sanitary and social inequity among studied populations. Finally, the advantages of adopting public health measures such as vaccination and improvement of sanitary and socioeconomic conditions are discussed.

Clinical characteristics of patients with acute hepatitis A in Gwangju-Chonnam province for recent 10 years / 대한내과학회지

No abstract available.

An Outbreak of Hepatitis A in South Korean Military Personnel: A Clinical and Epidemiologic Study / 대한간학회지

BACKGROUND/AIMS: Increasing the susceptibility of young populations to HAV infection could result in an outbreak in a high-risk group. The author investigated the characteristics of hepatitis A outbreaks among Korean military personnel to obtain the fundamental data for determining the necessity for selective HAV vaccination. METHODS: A case was defined as a person who had an onset of an illness compatible with acute viral hepatitis A between 4 February and 6 April 1998. RESULTS: A widespread outbreak of hepatitis A affected 102 military personnel. The epidemic curve indicated a common-source exposure in the initial stage. At the end of the first month of the initial onset, the occurrence was specific to the location of the military post. Investigation suggested that contamination most likely occurred prior to the local distribution of food. The mean age was 23 years. The overall attack rate was 91 cases per 10000 persons at risk. All cases were jaundiced. The most frequently reported symptoms included icteric sclerae, dark urine, anorexia, malaise and fatigue, nausea, fever, abdominal pain, headache, upper respiratory symptoms, vomiting, itching, diarrhea, light-colored stools, myalgia, arthralgia, and skin rash. The laboratory test showed the serum total bilirubin of 5.5 mg/dL, AST of 344 IU/L, and ALT of 868 IU/L (mean value). CONCLUSION: All patients were clinically apparently diseased with jaundice and were completely recovered. The outbreak was food borne common-source exposure. The changing epidemiology hepatitis A in Korea calls for the economic evaluation of costs and benefits for selective HAV vaccination in high risk adult groups including military personnel.

Molecular Epidemiology of Korean Strains of Hepatitis A Virus / 대한간학회지

BACKGROUND/AIMS: Studies of genotypes and changes in nucleotide and amino acid sequences of hepatitis A virus (HAV) may provide valuable information on the epidemiological aspects of a particular region. In Korea the prevalence of anti-HAV in the 1 - 20 year age group declined from 60% in 1980 to 9% in 1995. As a result this age group has a high risk of HAV infection. Actually over 1,500 cases of clinically overt hepatitis A occurred in 1998 while few cases of clinical hepatitis A had been reported until the early 1990s. The aims of this study are to determine the genotypes of HAV which have been circulating in Korea and to define the phylogenetic relationships of geographically defined isolates. METHOD: From 1994 - 1998 a total of 18 serum specimens was obtained from patients in Korea with sporadic form acute hepatitis A. The HAV nucleic acid from serum specimens was subjected to genomic sequence analysis following viral RNA extraction, reverse transcription and amplification of the cDNA by PCR. DNA sequencing was performed in both directions of each PCR product. RESULTS: All isolates clustered within the subgenotype IA irrespective of the geographic locations and timing of the clinical hepatitis. Among 18 Korean isolates, 9 isolates had 2 amino acid sequence changes and 2 isolates had 1 amino acid sequence change. These changes in the amino acid sequences are unique and have never been reported in HAV subgenotype IA. CONCLUSIONS: All isolated HAV had genotype (IA). Eleven of 18 isolates had unique changes in amino acid sequences. These data indicate that the endemic HAV has been circulating in Korea over a long period of time.

Clinical Features of Hepatitis A in Korean Adults / 대한내과학회지

OBJECTIVE: This study was aimed to characterize the clinical features and course of acute hepatitis A in Korean adults. METHODS: One-hundred and thirteen cases of acute hepatitis A, diagnosed between Jan. 1995 to July 1998 at 6 medical centers in Korea, were reviewed retrospectively. The clinical course of 94 cases with follow-up duration longer than 3 months were analyzed. RESULTS: The median age was 26 (16-65) years and 97.3% of the patients were under 40 years. The presumed sources of infection were identifed in 62 cases (54.9%). Among those, the leading source was ingestion of raw food. All patients showed normalization of bilirubin level within 8 weeks. The ALT levels normalized within 8 weeks in all patients except three patients (3.2%). Three patients with prolonged elevation of ALT showed second rise of ALT, suggesting a possibility of relapsing hepatitis. Prolonged fever (>38 degree C) more than 10 days was observed in 3 patients (3.2%). One case showed prolonged elevation of alkaline phosphatase (> x3 upper normal limit). No case of fulminant hepatic failure or death was observed. CONCLUSION: The majority of cases with acute hepatitis A in Korean adults showed self-limited course with full recovery.